I'm sure that a few of our regular viewers will be surprised to see that I now have a co-host for this channel, but I do want to thank Max for his amazing contribution to this tiny, non-monetized channel.
Cheerio Posh Arthur, you are looking very appropriately toff indeed 🤖🎩 If I may, I can offer some insight into your spectral analysis of these light sources that you have. The 532nm green laser pointer has a peak at 820nm because this is the wavelength of the GaAs laser diode used to pump the Nd:YVO4 crystal inside which then lases at the fundamental neodymium line at 1064nm, and which THEN is frequency doubled by a potassium titanyl phosphate crystal to 532nm green. Also, your violet diode laser at 22:00 and your red laser at 20:30 are direct diode lasers, there is no pumping of a secondary lasing medium. The line you see at 820nm for the violet laser is just a second order diffraction line, but the small peak at 750nm for the red laser is not. The higher order diffraction peaks will always be at exactly whole single digit multiples of the fundamental line. I suspect the line at 750nm for your red laser, and the small peak at 622nm for your 532nm green laser, AND the small peak at 500nm for your 410nm violet laser are simply an unwanted internal Fresnel surface reflection off the first side of the couple mm thick DVD being used as a diffraction grating on the "Garden" spectrometer. Notice how they only appear on the Garden, and they're always offset 90nm from the brightest peak. Your analysis of the 450nm laser is accurate. I wonder if it is possible to remove the phosphor from a CFL source like that by immersing the tube in an ultrasonic cleaner bath, which then could be used to observe the mercury lines in complete isolation, as from an uncoated germicidal bulb. Pip pip old chap. Looking forward to part 2.
@@Muonium1 Hi and thank you very much for the detailed explanation. Actually a few other viewers have helped me with this too. Max, Arthur and myself are always pleased to be learning, even by mistakes. Far too many YT creators are very resistant to corrections (Veritasium comes to mind), so thank you for your help!
Hello everyone! I'm Max, one of your co-hosts, and I'm thrilled to be here with you all. We're excited to share some interesting content with you - from laughs and learning to complete annihilation of all organic life on earth by my co-host Posh Arthur.
Woah, I had to check to be sure this was the channel I thought it was. I'm all for trying new styles and approaches. Glad 'Posh' Arthur wasn't fired. His dry humor is important.
It's nice to see fluorescent lamp (i.e. argon and mercury) spectral lines. I remember them from my time in high school (ca. 1980) where I volunteered to repair a physics classroom spectroscope. It had a 60 degree prism, two optical tubes at adjustable angles, and was just missing an eyepiece, which I substituted by fitting an objective lens from my 8mm film camera. It was basically the original Bunsen's design from ca. 1900. Good resolution, as long as the slit was kept narrow enough. I could clearly see the double line of sodium, as well as Fraunhofer dark equivalent in sunlight. Compared to this, the resolution of the two spectrometers reviewed leaves a lot to be desired, especially the small one. I believe TLM-2 design relies on interpolation to such a degree that its results are somewhat misleading. It likely shows any number of close lines as if they were one, as long as they fall on the same pair of pixels of the light sensor. In other words, it will calculate a weighted average of wavelength and add up intensity. So the high accuracy for a sparse spectrum probably belies much lower resolution of a busy one. Try it using a neon lamp, which has a lot of lines close together in the orange-red part of the spectrum. It will likely not resolve very many of them.
I will be doing exactly as you suggest with a Neon lamp source. As part of another video I'm working on, I will be discussing how to use these cheapo spectrometers to identify elements. I'll post a pic I got from the TLM-2 on the community tab in a few mins, keep an eye open for that!
Correction @20:00, the green laser pointer uses an 808nm pump diode to drive an Nd:YAG medium that outputs 1024nm... you may see residual emissions in both of these underlying frequencies, though the KTP only doubles the 1024nm source light.
One additional request for the TLM-2. Have software available for Linux systems. There are millions of Raspberry Pi 5/4/..., Orange Pi 5 Plus, etc systems that amateur and professional scientists use daily. Those interested in atmospheric and astronomical physics/sciences, meteorologists, climatologists and just STEM students and programs that can use the TLM-2 to do research with the small cheap microcomputer systems. If you go open source, you would get 1,000s of programmers to come up the best software that would ordinarily cost millions of dollars (in any currency). Even setup a web page for a repository and competition. The company could come up with a cash prize for the best software submitted for open source and sharing with the Universe at large. Go big and sell a lot of hardware. In my humble opinion. Submitted for your consideration. This could be the greatest thing since sliced bread.
Imagine not just offering Linux support, but fully embracing an open-source ecosystem that not only supports these systems but becomes a cornerstone of global collaboration. You could position the TLM-2 as the essential tool for anyone passionate about environmental monitoring, astronomy, or even cutting-edge climate science - and then expand this to other fields of research. This would open the door to users you may not have considered: marine biologists monitoring oceanic weather, urban planners using microclimate data for smart cities, and even educators incorporating real-time data collection into their STEM curricula.
I no longer have a commercial need. But my scientific mind wants one to be added to the selection of it it can be measured I want to be able to measure it. As a former repair technician in the analog days of video and early digital cameras I had to have a calibrated light of a known color temperature. The cheapest way was to use 12V halogen downlights and run them at 14.8V where they only had a short but useful life.
This video is quite a surprise. Well done! I was considering ordering the Little Garden device through a third party company but I'll wait until part 2 of the video is released and draw my conclusions then.
In the green laser the 808 nm is the actual LED wavelength. The light gets converted to 1064 nm (fluorescence) in a Nd:YAG crystal, and after that passes through KTP crystal which doubles the frequency to 532 nm.
@@Peterkramer929that's basically exactly what it does. The math works out super close to both input photons only being half the output energy respectively. Even more fun, there are processes working the other way round! Look up SPDC and you'll be even more impressed :). Back in the days I built entangled photon sources by the use of UV lasers with a Type 2 BBO crystal. The process occurs only rare times and most of the UV passes straight through. Some UV photons get split into 2 red photons, also being orthogonally oriented in their polarization plane. You can "easily" dm Separate them by using Pol filters :D
@@leandroebner1405 I did SPDC generation in my masters and both generation and recombination in my phd thesis. It's one amazing process, but quite inefficient as you've mentioned. I did some calculations for BBO, but ended up doing type 0 (same polarization of both photons) in a periodically-poled KTP crystal with periodicity just over 3 um. With ~100 mW of 405 nm we got a hundred thousand pairs per second or so, and up to a few thousand recombinations per second. Recombination is ultra-challenging, both theoretically and experimentally, I think it'll be an important part of quantum signal processing in the future. One interesting thing about type 0 in PPKTP is the way you can change the phase-matching conditions with both temperature and angle of the crystal. You can get collinear-degenerate, collinear non-degenerate, or non-collinear interactions, all with the same crystal.
@@leandroebner1405 I used to teach my kids that once an electron got into an excited state it would immediately(!) fall back to a lower state, emitting a few lower f (and therefore E) photons. Or perhaps one with the same f when the electron would, in one step, go to the ground state. But that it is impossible to excite an electron in two steps. What I understand from you is that you need two exact same photons at the exact same time(?) I'll look into it.
The signal at 21:38 is produce by the 808nm laser diode in the green laser. The green laser in the video is a DPSS(Diilde pump soild state laser). which use a 808nm laser diode as a source, then pump it to 1064nm, then frequency double to 532nm.
Thanks for the feedback, several others have also pointed this out. In the next video (will be released tonight) there is a correction and a demonstration of this. Thanks!
Looking forward to 2nd video. Would purchase a few units if software was fixed. Rescaling window size, remembering parameters, and outputting CSV data are obvious must. Thank you.
I'm looking forward to the second part. For sure I am interested in the device, as long as the manufacturer does not intentionally cripple functions just to charge more without justifiable costs - I've given up on FLIR thermal imagers beacause of such behavior. One more question that was not raised in the video: why use an USB mini-B connector in 2024?
There is a USB-Serial converter inside the cable housing - my guess is that because the mini-USB is not common, it help to reduce the number of people that are likely to plug it directly into a USB port...
@@project-326 there is an SDK, I got the document from their website using my product number, it's very likely the same protocol. Can share if desired, just let me know of a contact address.
Haha i truly don't have a lot of confidence that they can write good software. SDK or hardware interfacing open documentation would allow some interesting uses. Someone needs a monitor calibrator? Might turn out better than any other.
@@SianaGearz I also have a fairly low confidence, their core team is basically scientists, what they need to get to market is more engineers. Its the classic start-up problem...
VERY interesting! Instant new subscriber with the bell clicked (I never do that 😮) You might have explained it in the Little Garden vid (going there right now), but I’d love to hear the details of how they get 5nm resolution out of just a few quantum dots.
I built a crappy version of the little garden based on your tear down from the last video actually. I wanted to get one badly, but figured that it was too difficult so I tried to pull it off. I didn't use the monochrome camera, as I could find one (recently I got one, but haven't done anything with it), that said its quite limited, but was super fun to make. I love these videos, they make you think about products.
OK, so I had a lot of very detailed discussion with the creator of the 'little garden' device. It seems I made a mistake in my original video. He is not buying monochrome camera (that is too expensive, due to the very low demand) but manually cleaning of the Bayer Filter. I have a lot of respect for that guy and will be including a whole segment on him in the next video.
I also tried to build one myself - it really made me appreciate the 'little Garden" device a LOT more. Sometimes, its the journey that is more interesting than the destination...
@@project-326 that would explain a lot, haha I spent hours trying to figure out if I bought the wrong camera module. Cleaning the Bayer Filter sounds like delicate work that take a lot of effort. Cant wait to see the process!
Sorry to add more stuff. 1. Use the TLM-2 to check safety glasses for bandpass and attenuation regions. 2. For the big color squatters and even Home Depot: use spectrometer to check their color patches at the store with the final color of the applied paint to different surfaces. 3. I want to check for UV output for the Chinese made LED bar lamps I use at the desk for bright white reading source, electronic assembly and soldering and video lighting. 4. Looks like around a 1cm diameter of the input diffuser. When you get sunlight, I am guessing 1316W/m^2 multiplied by 0.00007854 (area ratio) = 0.1068W/m^2 input in sunlight without pollution etc. With CSV data we can do the integration for calibration or atmospheric effect measurements. Thanks for all the hard work and I can understand the two week period between videos. It is greatly appreciated. Are the background squares 1cm in your TLM-2 videos? Inquiring minds want to know.
This is great, the more applications the better, a tool is only useful if it has a job to perform! I need to check on the mat, I have two, one is 1cm and the other is 1" (I do photography in 2 different locations)...
Thanks for the in depth review. It's a very interesting product, it would be much nicer if the apps were had the basic functionality working really reliably. The mobile apps need to find the unit faster and the PC app needs to remember settings. A USB C socket would be highly appreciated too. P.s. Please retire the slow robot voice and refrain from repeating the same information you just said when you switch to the spectrum results.
Nice device. It would be nice to have a machine readable export format. And it would be nice to have higher precision of the small device combined with the finer resolution of the bigger one.
If I had time for that, I'd look into possible hacky modifications. Those devices send their simple data packets over the com part without any encryption. Don think their company would like that approach tho. But that's what happens by making silly decisions the customer has to life with.
Great review and cool device! Looking forward to seeing the second part! I'd suggest that non-proprietary parts of the user interface software be open source. The difficult parts are the hardware and any secret sauce they have for calibration and signal processing. The UI parts where the processed output data is displayed should be open so users can customize it or integrate it with their own tools. This would also allow users to contribute features and bug fixes back to the official UI project, improving the product for everyone.
If this is just a COM port, surely you can just write translation layer and use something like ArgyllCMS. Or whatever software to your liking. Edit: Would have liked to see the insides. But I see that coming. Looks like another camera sensor. Would have thought a linear scanner CCD as better, but I guess optics would need to much better then as well as a size increase. Please keep finding these gems. Edit2: Would you mind testing these for color calibration (I see their software does do something for that with xy coords)?
An important note!! None of the lasers used (besides the green 532nm unit) use a frequency doubling crystal. The infrared lines are artifacts on the spectrometer.
Like you said, CSV export is pretty important. The other thing I'd like to see is the software being open source so there are no questions about its safety.
Some of your extra peaks are artifacts of the way these spectrometer works and not actually in the light source. You can confirm this with some filters.
Great review! Hope you could mention that most engineering filaments requires an enclosure or even a actively heated enclosure to print, which is not obvious for people who has never printed them.
Turns out the IR peaks are from the diode pumping architecture of the laser. I put some errata into the latest video on the 'little garden' spectrometer. That errata is equally applicable for this video.
Excellent video. Thank you. One thing, I think you should put a pure black of an inch just in front of the emitter and the receptor (spectrometer), the objetive is to achieve optical engagement without the reflection of other surfaces, in this case the rubber you use. The emitter projects its radiation on the rubber and contaminate part of the rays reach the recepto. Of course, there are a lot of other variables to control; e.g., vacuum, humidity, distance, air composition, etc., etc., but at least, I suggest, you can control the distance between the tubes. I mean: emitter + 0 mm + 2.54 mm (the output non-reflective tube) + 2.54 mm (air distance) + 2.54 mm (the input non-reflective tube) + 0 mm + spectrometer-receptor. Maybe, maybe not, it would improve the results. What do you think? Anyhow, I just want to thank you for your video; I would love to have that marvellous hardware you can get in China. I would make "gun shape form" or pointer, spectrometer; with a laser telemeter to adjust the efect of distance of the surrounding gases (mostly cases air.) I would make may own typical base measurements to stablish sets of spectrographic data base; as well the corrections due to distance, angle or another variable that would apply. And app and small devise like that would be easy for ordinary citizen usage than other portable radioactive spectrographs. It should be quite use full to very quick draft material checks: canvas, woods, metals, cristal, food, etc.,
This is indeed a fantastic find. Many thanks for the video. I will be at the opening gate to buy one as soon as Amazon has them online. I want one to measure twilight colorimetry to match a paper I did almost 50 years ago. Was in the process of building a DIY spectrometer, but now I can relax and await the opening bell for the TLM-2. Another test I'm interested in. Variable incandescent lamp to measure blackbody curve vs temperature for calibration. Question: Has anyone checked for heating in the diffuser as a possible source for the IR contribution?
Hi so thanks for the cool review! I am interested in maybe using one of these to obtain spectra of meteors coming into earth’s atmosphere. I will wager that the light from the meteor will be too dim for the camera, but I thought I would ask! Thanks again!!
One issue that cheap array spectrometers suffer from is straylight, especially excess signal In the blue/UV. Grading instruments can have order sorting filters and multiple gratings to eliminate. This one has some filtration on the pixels and a magic algorithm. I’d have done some tests with a broadband source and a thick bit of various schott coloured filters, see if you get any signal where you should see none. You could also check you “higher order effect” hypothesis by filtering the source so there is no light in that spectral region and then seeing if the higher order lines appear. Calibrated, how, against what and for what sources? Interesting little device. No numbers out is no sales made. No way to check noise floor, stray light etc. roll on part 2.
I wanted to know more about creation of monochromatic source of light and embodying the same into a Laser! What does the terms ‘Source Wave Length’ and its multiplicand’ means? How the mulltiplication of frequency of light is achieved, in practice?
Very nicely explained and demonstrated! I wanted to look for different lines of emission from pure hydrogen spectra; particularly of Balmer & Paschen series. I wanted to get assured about the same! Or whether we were just tought to be so! Thanks.
That is exactly why I like to make experiments on this channel, nothing beats seeing stuff for yourself, even if the results are way less impressive than from a professional lab. The reason people still buy telescopes is for exactly the same reason, nobody can beat the Hubble of JWST images but those are someone else's results. Seeing a tiny, dim, fuzzy, monochrome image of the rings of Saturn, with your own eyes, beats all of those beautiful on-line images from the pros. I'm going to look into finding a low pressure H2 tube...
@@project-326 I have a different version of their spectrometer, the PJG3, which came with the information regarding the serial port commands and data packets. This may be useful for your purposes. The data isn't encrypted from the looks of it. The document is in chinese, but translation by machine seemed to have worked very well. Now, I can't actually test it yet because they don't have the pinout for the TTL interface printed or written anywhere! The PJG3 version has no usb output, but rather a 4 pin serial interface that is completely unmarked and doesn't come with a pinout diagram (nor is it included in the manual for the client interface or for the SDK). So, I've written to the company just yesterday to inquire about this. Their Alibaba store is offline now, so I had to write to their email. No answer yet, I sent them a machine translation version a few hours ago, hopefully they'll come through and provide this info. Cheers!
Wow.. i love it! I still remember using room sized monochromators (25 years ago) with a knob to manually rotate through each wavelength - used to take 4 hours to get a reading!!! Specifically on the device, the physics looks sound! The key thing is to be able to easily get raw data out, have quick analysis, and perhaps upload target spectra to the mobile/tablet. Also if it canbgenerate CIE coordinates, that woukd be great. Finally lower the price, tge more people will use it, but there needs to be a good build quality. I'm looking forward to buying one!
To the manufacturer: I direly want a spectral analyzer tool. if you add a CSV export OR a CRI rating, I would try to buy it if it is available in Germany. Please add CSV export or CRI measurement
I have that exact 450 nm pointer. It is not a DPSSL, it's direct eiode, so there should be no IR emission. I would suspect the same for the 410 nm, not that DPSSL is impossible, but they would cost more than 10x as much as a direct diode laser. Looking at the spectral width, I am fairly sure these should both be direct diode lasers. You should be able to tell by which way the batteries are inserted, or, you might be able to open them up to see the module. The 532 nm, however, is indeed, more likely, DPSSL, pumped with an 808 nm IR laser, so that is reassuring... however, the artefacts for the near UV lasers is concerning to me. I'm 98% sure something is wrong with the spectromeret... higher order diffraction or some other interference, rather than an issue with the laser. Still, though, both products are interesting to me. If they are available in the USA for under $150, I'd seriously consider these. If they go higher than that, they'll already be in competition with other super-low cost spectrometers that seem to have fewer reported bugs.
Yup, if figured that out from some other comments. I will be making some corrections in the next part of the video. Thank you for the corrections, learning is something I never want to stop doing and having people that know something I don't, point out mistakes in the comments is a positive experience for me.
I wonder what the spectrum of various video monitors is. If some are more narrow-band than others, and which are the better ones. We already know or look up common lighting sources.
Since it appears that this new model has a reflected diffraction grating (im hoping it is surface reflective) and they made their own sensor, im wondering if they could increase the spectral range further into the UV. If that is not possible to keep it in budget, it would be nice to see an affordable model that maybe starts in blue or violet, but can function down to 200 or 250nm.
@@peterwoolliams1283 I understand that if they attempt to go into the UV, they have to make sure all the optical components and materials don't absorb UV along the way. I'm thinking about using such a device with microscope illuminators that (they claim) pass UV as short as 250nm. (Some of the quarts lenses I have claim to be rated to 200nm). eBay has been great for finding deals for most of my hobby, though, (working) UV spectrometers are not one of them. Hope is all I have now!!!!
I want to get one as well. Having a CSV data output would be great as well because then we can run in through other applications or just save it in a database for future reference and calibration.
You'll run into a dead end pretty soon when you can't to anything with the data you measured. Agreed. Not a total dealbreaker because that thing in that price range is less a scientific tool and more a fun nerdy gadget
What happens if you remove the diffuser? Might it be possible to attach to a telescope and look at spectra of individual stars? Inquiring minds want to know. Hopefully you have another after the reverse engineering exercise? Thanks in advance.
I'm not sure how it would be focused down into the slit and how that would affect the measurement. the diffusor is easily removed, but I that will effect the calibration of the intensity...
I was able to get both the spectrometers that you have listed on here and I look forward to trying them out. The TLM2 you mentioned seems to be labeled the P3, and its filed under color illuminance meters, and is good for 340 - 780nm. There spectrometer section has some different models with some higher spectral ranges including a quantum dot spectrometer...curious to benefits of that compared to the model you currently have. I'm guessing the video you are referring to showing the video on this is where you have the ampules of gasses you are looking at? Thats a really cool process that showed me this is possible, but I guess I am wondering if I'm looking at a Geissler tube that has had vapors and gases sealed for over a hundred years, there could have been reactions changing things inside the tube and my wonder is, Do these cover spectral ranges enough to gather data and evidence on such things? or would I need to step up to a wider range on the spectrum? Thanks for your help and great work!!
How does this unit compare the the Changhong H2 mobile phone, which had a spectrometer built in? I cannot find one in my current location, but maybe you could find a second hand H2 and do some comparison tests? Also, have you seen Jerry De Vos' implementation of an open source plastics spectrometer project?
I would be interested in one of these, but only if the suggested improvements in the video were made, and especially if the software for it was made to be open source. An additional suggestion would be for it to be USB-C compatible.
its using the old Mini-USB because its not USB, but serial UART. There is a USB-UART converter in the cable itself. Hopefully they can improve that too.
@@project-326 unfortunately I don't. All I could find is that ethanol has more lines due to the fact it's more complex therefore has more paths to burn.
There should be CSV output, but I wonder if the pdf might be able to be "read" by Chat GPT which would output what it "saw" in your format of choice? Edit: I just tried it with Claude and it told me that the resolution of the chart I gave it wasn't good enough for accurate reading. I'd like to see the PDF output of this instrument. If high enough resolution it may work.
Regarding the green laser: The small IR peak is from the IR pumping diode which then goes through two crystals which do the frequency doubling, etc. This green laser appears to adequately filter out the IR but many do not. Edit: You mention this with the violet laser. I see this video took a while to put together, LOL
Thank you, I have already be 'educated' in that aspect by another kind viewer. The thing I like best about making these videos is that there are always people with more knowledge to learn from. I didn't realize that the green laser was a 3 stage process. Its amazing how much technology can be crammed into a $10 laser pointer...
@@project-326 They're cheap as chips today but i remember when green pointers cost the earth in the earliest days of the internet. BTW, they now make fully SS 488mn blueish-green ones with just the diode - I own one. I need to develop my own YT channel with all the tech junk I've accrued over the years. LOL. I'm glad you welcomed my earlier explanation on this public forum and I'm certainly learning a lot from your good self. Can't wait for the second half.
@@leandroebner1405 I was one of those that worked on early CD player technology, the whole CD mechanism and OPU ended up costing less than $1.50 in serious volume, in particular the Sanyo DA11 was just an amazing piece of optical technology for its time that somehow also had the distinction of costing the same as a candy bar... If that same technology had been developed for the military, each CD mechanism would have cost about $150K...
I got mine on TaoBao, but that is only available in Mainland China. I found some similar ones on AliExpress using search terms that included USB, but they were just similar and not identical. Sorry, lost that link...
We are looking at 'maybe' doing some raman spectroscopy, but that depends on the costs involved. We have been also doing some experiments with the spectra of various plasma. We might be able to think up some interesting experiments in that area if we get time.
I’d be interested in seeing flame tests of some chemicals just for variety. Not table salt, but something more complex. I could see buying one of these when they have CSV, although I don’t need it.
Besides resolution, an issue of spectrometers using webcams is that the gain (amplitude) in various channels is not constant, due to processingin the webcam algorithm, so different spectra cannot be compared. Is this using a constant gain, so that I can calibrate and get good results? Without a calibration and constant gain, the spectra are useful only for looking at them, you cannot even measure the CRI of a LED light. And what about the Garden spectrometer?
The TLM2 isn't using a webcam. They are buying a monochrome CMOS die and getting the QD's deposited onto the sensor directly before the passivization is added. I'm guessing that they are getting the image sensor vendor to do this for them in the fab as a custom version. The TLM2 appears to be pre-calibrated for level and that cannot be changed. The little garden device will suffer from the issues that you mention, the levels for each of the color channels will be optimized for the 'best picture' for human eyes, not best optimization for photon energy. These types of sensors usually have some OTP ROM that allows the product level manufacturer to set up the color balance, the gain transfer function, etc and those settings will have already been burnt in before the creator of the LG device received the camera module. The creator of the LG device has released that on AliExpress and there is a link to the store in a post in the community section of this channel.
A reasonable software in English is a prerequisite for international marketing. Is it so difficult to remember the language and the COM port? Is it that difficult to install a usable image export?
As mentioned in the video, it isn't available in the west yet, but the company is planning to release on Amazon soon (part 2 of the video is planned for when that happens). I added the TaoBao store details where I got this product from to the video description, but this only works from China...
well, in theory yes, but in practice, probably no. The problem is that this device needs a fairly stable light source for several seconds, so a brief spark wouldn't give a result. I hope that helps!
Brilliant video and product. I’d argue that they are locking out the CSV export whilst they figure out the business model. There’s maybe 2000 one off spectrometer hobbyists who’d buy this for home use and that’s the market done. I’m in already. However if you integrate it into another mass market volume product such as a vehicle or specialised lighting product then your market becomes scalable. I’d reckon that’s where this is headed.
Thank you for the comment. Some of my own thoughts... Each time I use this device, I seem to find a new application. For example, our IR chroma-key video, it was useful for seeing how spectrally pure a commercial green screen actually was (answer, not very). Amateur film makers will find this useful and because of the low cost, photographers can now have a much better tool than the 3 color sensors that are normally used. Anyone involved in pro lighting is also a potential customer. Basic class room education is also opened up, instead of a high school having one $2000 system to share between all classes, there can be more devices available. Anyone involved in the print and finishing industry, QA technicians and product designers. The list just gets longer each time I think about it... This device has earned a valuable place in my work bag, I am really strict about what I carry around but its really useful for far more things than I ever imagined. As for the company, as a tech start-up, their core team are basically scientists and PhD's, so I hope that they can get the help they need with the product marketing going forward.
Does ionizable radiation make the florescent coating on LEDs glow? what is the strength of this ionizable radiation? Can florescent coated LEDs visually indicate the presence of fallout? Assume they had these LEDs in Pripyat will they see unpowered glowing LEDs? Also does ionizable radiation damage the florescent coating? Another question. Since florescent material degrade with time will florescent coated LEDs lose their color after decades?
Well that's a good few questions... OK, so fluorescent materials are used as scintillation crystals in devices like gamma ray spectrometers, but each type of fluorescent material has different wavelengths that it will be excited by. I would doubt that the materials used for LED production would be useful for gamma rays. Another issue is the number of photons. gamma rays have a LOT more energy per photon, if you had a gamma ray source that emitted the same number of photons as just a small LED, you would basically have a death ray on your hands! Because the number of gamma rays photons is pretty low in the background, gamma ray scintillation crystals need to be connected to detectors that can be sensitive to just single photon events. Radium watch dials, for example, lose their luminosity in a few decades as the fluorescent material crystal structure becomes damaged by years of alpha particle bombardment, and stop glowing. The dangerous thing about that is that the Ra-224 has a half-life of about 1600 years. People often think that dials that no longer glow are no longer radioactive which can lead to some poor decision making in the disposal of the dials. I would assume that there will be a small amount of similar damage by a 450nm blue photon on an LED flourescent coating, but given that the energy of a photon at these wavelengths is about 10^9 times lower, I would assume that the damage would accumulate a billion times more slowly.
I love your channel and just wanted to make you aware I prefer long fourm videos. Making the videos shorter trims out your humorous side and the depth of the information provided.
@@electrobus5095 Every week... I am making a new video that includes this device and I am going to include a segment that will encourage viewers to bombard their email address with requests to buy this device. Hopefully they might finally believe that there is demand for this outside of China!
Would be nice if there was an option to use it like a camera: snap timestamped spectrogram data to an SD card and look at the plots or csv afterwards. (Even if it had to be powered by USB)
I ordered the little garden from China after saw you video - its working surprising nice. Also I prefer you keep the robotic voice instead of real human voice 😆😆
That is not an easy answer to give, it depends on the bandwidth of the light source and the area of the beam cross-section. The TLM-2 is rated with a 10-10000 lux range. For example, a 555 nm laser beam (FWHM = 1nm) with 10mm2 of beam cross-section would result in a maximum power of about 1W. If the energy is spread over the typical spectra of sunlight, then the device range will be limited to about 2.196 mW.
because of the very short optical path, the resolution would be terrible without the QDs. Your question was a really good one and perfectly valid, so I sent your question to the manufacturer, here is their response: "The reason we utilize both is that either of them can not provide enough resolution solo. The QDs we synthesized have too broad absorption bands to resolve the spectrum with high resolution and wide wavelength range. The same thing happened to the diffraction grating due to the small size of the device we try to achieve. Then we decided to combine the two techniques, and got amazing results."
I would be interested by the TM2 however no access to the data no purchase! put an open-source software on it pls. Finally the mini USB plug is outdated. Cables start to be harder to find.
I think they chose a mini-USB because it is now just a USB cable, it is the USB-Serial converter and people are less likely to plug in a standard USB cable buy accident. At least that's my conclusion...
@@project-326 I'm not sure to fully understand. usb to serial you normally plug it to a normal usb port on your computer it work with usb-C as well all Arduino like stuffs use that no issue. Now if i have to understand that they use a mini usb plug for a different purpose than usb that is a drama guaranteed recipe as someone will end plugging this in a computer usb plug generating a magic smoke emission.
Yes, I hope that they can fix these deficiencies. I'm interested in purchasing a low-cost spectrometer; I have a product I'm developing that I need a tool such as this to explore the light sources I plan to use in it! Upfront: The Functionality and Price will be determining factors in my purchase decision. I agree with the criticism about the software's abilities, they need to be improved. Please, do spend some more time to polish it up before releasing. Even the ability to connect to that 3rd party's open source software might be a good way to get it there, just a suggestion. I think it is wonderful to have an opportunity to communicate and be part of the community that helps shape the product's we use! And for the manufacturer, it must be a great opportunity for you to get direct and useful feedback by the customers. In any event, I'm looking forward to part 2 and see if we made a difference. Thanks a bunch!
yes, I am hoping that the manufacturer will be responsive too. What I really like about this unit is the size. It now lives in my work bag on a permanent basis...
You are wrong for 405 nm laser. It is InGaN laser meaning there is no way IR can be generated. What you see is second order peak from the grating. Spectroscopy basics.
The potential of this product is evident, but the manufacturer needs to enhance its software and address any issues. They should strive to create a highly marketable product, where the design and features are of utmost importance. Integrating AI capabilities into the software could take the product to the next level.
Where can I get some of those LED bulbs featured? Perhaps they are available on other markets? AliExpress, DHGate, etc. what is the brand or model of the LED bulbs?
These aren't exactly the same, but similar... www.aliexpress.com/item/1005006768029309.html?spm=a2g0o.productlist.main.21.7489zyZpzyZpq5&algo_pvid=9c8238f8-6e27-4510-8a7e-5fac01281b6a&algo_exp_id=9c8238f8-6e27-4510-8a7e-5fac01281b6a-10&pdp_npi=4%40dis%21USD%217.19%215.18%21%21%2152.17%2137.56%21%402167359c17198154480454097eb4e2%2112000039994356366%21sea%21HK%212881401294%21AB&curPageLogUid=boPe8mK5GVRW&utparam-url=scene%3Asearch%7Cquery_from%3A
Clever device, good video. Pity about the software. If the user interface is that bad, no user will want to use it. It would be well worth it to the manufacturer to improve the software.
This kind of affordable spectrometer is really useful for lighting designers and others invo!ved in architectural lighting design for confirmation of product specification. Also increasingly important in other areas of professional lighting such as photography and videography. So far the product seems pretty good for our kinds of use with sufficient resolution and accuracy. Typically the output format in PDF isOK if we have enough detail and refencesto ISO and CIE standards however CSV is necessary For calculating colour fidelity and also for melanopic effectiveness through standard tools freely available from IES and CIE. Price in the market is also important as will be thelevel of calibration against traceable standards to NIST or other international standards. Also how about recalibration? If it is cheap enough and calibration from new is warrantied for say 2 years then replace that would be good enough if the unit is cheap enough. Currently I need to replace my existing spectrophotometer as the company who made it are out of business and it cannot be recalibrated also there is no software support for it
![A Tiny Micro-Spectrometer - Reviewed [Pt2]](http://i.ytimg.com/vi/URxE2nMVzpw/mqdefault.jpg)
![A Tiny Micro-Spectrometer - Reviewed [Pt2]](/img/tr.png)
I'm sure that a few of our regular viewers will be surprised to see that I now have a co-host for this channel, but I do want to thank Max for his amazing contribution to this tiny, non-monetized channel.
Indeed, good work Max, looking forward to more cooperation very soon.
My pleasure Arthur!
Cheerio Posh Arthur, you are looking very appropriately toff indeed 🤖🎩 If I may, I can offer some insight into your spectral analysis of these light sources that you have. The 532nm green laser pointer has a peak at 820nm because this is the wavelength of the GaAs laser diode used to pump the Nd:YVO4 crystal inside which then lases at the fundamental neodymium line at 1064nm, and which THEN is frequency doubled by a potassium titanyl phosphate crystal to 532nm green. Also, your violet diode laser at 22:00 and your red laser at 20:30 are direct diode lasers, there is no pumping of a secondary lasing medium. The line you see at 820nm for the violet laser is just a second order diffraction line, but the small peak at 750nm for the red laser is not. The higher order diffraction peaks will always be at exactly whole single digit multiples of the fundamental line. I suspect the line at 750nm for your red laser, and the small peak at 622nm for your 532nm green laser, AND the small peak at 500nm for your 410nm violet laser are simply an unwanted internal Fresnel surface reflection off the first side of the couple mm thick DVD being used as a diffraction grating on the "Garden" spectrometer. Notice how they only appear on the Garden, and they're always offset 90nm from the brightest peak. Your analysis of the 450nm laser is accurate. I wonder if it is possible to remove the phosphor from a CFL source like that by immersing the tube in an ultrasonic cleaner bath, which then could be used to observe the mercury lines in complete isolation, as from an uncoated germicidal bulb. Pip pip old chap. Looking forward to part 2.
@@Muonium1 Hi and thank you very much for the detailed explanation. Actually a few other viewers have helped me with this too.
Max, Arthur and myself are always pleased to be learning, even by mistakes. Far too many YT creators are very resistant to corrections (Veritasium comes to mind), so thank you for your help!
@@Muonium1 Actually, I have a mercury vapor lamp to test in part 2...
Hello everyone! I'm Max, one of your co-hosts, and I'm thrilled to be here with you all. We're excited to share some interesting content with you - from laughs and learning to complete annihilation of all organic life on earth by my co-host Posh Arthur.
Woah, I had to check to be sure this was the channel I thought it was. I'm all for trying new styles and approaches. Glad 'Posh' Arthur wasn't fired. His dry humor is important.
Nobody can fire Posh Arthur, despite how naughty he is...
the humans can't get by without me, don't worry.
It's nice to see fluorescent lamp (i.e. argon and mercury) spectral lines. I remember them from my time in high school (ca. 1980) where I volunteered to repair a physics classroom spectroscope. It had a 60 degree prism, two optical tubes at adjustable angles, and was just missing an eyepiece, which I substituted by fitting an objective lens from my 8mm film camera. It was basically the original Bunsen's design from ca. 1900. Good resolution, as long as the slit was kept narrow enough. I could clearly see the double line of sodium, as well as Fraunhofer dark equivalent in sunlight. Compared to this, the resolution of the two spectrometers reviewed leaves a lot to be desired, especially the small one.
I believe TLM-2 design relies on interpolation to such a degree that its results are somewhat misleading. It likely shows any number of close lines as if they were one, as long as they fall on the same pair of pixels of the light sensor. In other words, it will calculate a weighted average of wavelength and add up intensity. So the high accuracy for a sparse spectrum probably belies much lower resolution of a busy one. Try it using a neon lamp, which has a lot of lines close together in the orange-red part of the spectrum. It will likely not resolve very many of them.
I will be doing exactly as you suggest with a Neon lamp source. As part of another video I'm working on, I will be discussing how to use these cheapo spectrometers to identify elements. I'll post a pic I got from the TLM-2 on the community tab in a few mins, keep an eye open for that!
@@project-326hehe, nice to hear that idea is in the making ^^
Correction @20:00, the green laser pointer uses an 808nm pump diode to drive an Nd:YAG medium that outputs 1024nm... you may see residual emissions in both of these underlying frequencies, though the KTP only doubles the 1024nm source light.
Thank you, this a a couple of other corrections will be in part 2 of the video.
One additional request for the TLM-2. Have software available for Linux systems. There are millions of Raspberry Pi 5/4/..., Orange Pi 5 Plus, etc systems that
amateur and professional scientists use daily. Those interested in atmospheric and astronomical physics/sciences, meteorologists, climatologists and just
STEM students and programs that can use the TLM-2 to do research with the small cheap microcomputer systems. If you go open source, you would get
1,000s of programmers to come up the best software that would ordinarily cost millions of dollars (in any currency). Even setup a web page for a repository
and competition. The company could come up with a cash prize for the best software submitted for open source and sharing with the Universe at large.
Go big and sell a lot of hardware. In my humble opinion. Submitted for your consideration. This could be the greatest thing since sliced bread.
This!
Imagine not just offering Linux support, but fully embracing an open-source ecosystem that not only supports these systems but becomes a cornerstone of global collaboration. You could position the TLM-2 as the essential tool for anyone passionate about environmental monitoring, astronomy, or even cutting-edge climate science - and then expand this to other fields of research. This would open the door to users you may not have considered: marine biologists monitoring oceanic weather, urban planners using microclimate data for smart cities, and even educators incorporating real-time data collection into their STEM curricula.
Option to select PDF or an SVG image output. The SVG for inclusion in scientific papers for publication.
This is such a cool channel Max, you are a wealth of knowledge. So happy I stumbled across you today, surprised it took as long as it did.
Welcome aboard!
Amazing little device, thank you for bringing it to us. Can't wait for part 2
Coming soon!
I no longer have a commercial need. But my scientific mind wants one to be added to the selection of it it can be measured I want to be able to measure it. As a former repair technician in the analog days of video and early digital cameras I had to have a calibrated light of a known color temperature. The cheapest way was to use 12V halogen downlights and run them at 14.8V where they only had a short but useful life.
This video is quite a surprise. Well done! I was considering ordering the Little Garden device through a third party company but I'll wait until part 2 of the video is released and draw my conclusions then.
a good plan!
We are already busy in the 2nd part...
In the green laser the 808 nm is the actual LED wavelength. The light gets converted to 1064 nm (fluorescence) in a Nd:YAG crystal, and after that passes through KTP crystal which doubles the frequency to 532 nm.
thanks for that info. It is the very best thing about a channel like this, I get to learn from smart people!
frequency doubling, how does that work? absorbing two photons, emitting one? (always thought that was impossible)
@@Peterkramer929that's basically exactly what it does. The math works out super close to both input photons only being half the output energy respectively. Even more fun, there are processes working the other way round! Look up SPDC and you'll be even more impressed :). Back in the days I built entangled photon sources by the use of UV lasers with a Type 2 BBO crystal. The process occurs only rare times and most of the UV passes straight through. Some UV photons get split into 2 red photons, also being orthogonally oriented in their polarization plane. You can "easily" dm Separate them by using Pol filters :D
@@leandroebner1405 I did SPDC generation in my masters and both generation and recombination in my phd thesis. It's one amazing process, but quite inefficient as you've mentioned. I did some calculations for BBO, but ended up doing type 0 (same polarization of both photons) in a periodically-poled KTP crystal with periodicity just over 3 um. With ~100 mW of 405 nm we got a hundred thousand pairs per second or so, and up to a few thousand recombinations per second. Recombination is ultra-challenging, both theoretically and experimentally, I think it'll be an important part of quantum signal processing in the future.
One interesting thing about type 0 in PPKTP is the way you can change the phase-matching conditions with both temperature and angle of the crystal. You can get collinear-degenerate, collinear non-degenerate, or non-collinear interactions, all with the same crystal.
@@leandroebner1405 I used to teach my kids that once an electron got into an excited state it would immediately(!) fall back to a lower state, emitting a few lower f (and therefore E) photons. Or perhaps one with the same f when the electron would, in one step, go to the ground state. But that it is impossible to excite an electron in two steps. What I understand from you is that you need two exact same photons at the exact same time(?) I'll look into it.
Eagerly awaiting part 2.
More eagerly awaiting the availability of the product in an online shop.
In progress, but please be patient, we want to be sure the manufacturer gets their head around the idea of listening to potential customers.
The signal at 21:38 is produce by the 808nm laser diode in the green laser. The green laser in the video is a DPSS(Diilde pump soild state laser). which use a 808nm laser diode as a source, then pump it to 1064nm, then frequency double to 532nm.
Thanks for the feedback, several others have also pointed this out. In the next video (will be released tonight) there is a correction and a demonstration of this.
Thanks!
lol, I can’t believe anyone else has that Peaches song. I used to listen to it while coding, about 20 years ago - and it still makes me smile.
Looking forward to 2nd video. Would purchase a few units if software was fixed.
Rescaling window size, remembering parameters, and outputting CSV data are
obvious must. Thank you.
I agree...these things need to be fixed before I would buy or recommend to others.
Really looking forward to part 2, and ready to order one to satisfy my curious-yet-poor self! Amazing video!
Awesome! Thank you!
I'm looking forward to the second part. For sure I am interested in the device, as long as the manufacturer does not intentionally cripple functions just to charge more without justifiable costs - I've given up on FLIR thermal imagers beacause of such behavior. One more question that was not raised in the video: why use an USB mini-B connector in 2024?
There is a USB-Serial converter inside the cable housing - my guess is that because the mini-USB is not common, it help to reduce the number of people that are likely to plug it directly into a USB port...
Ah ! another great video from Project 326 at last! You my friend are going places! really enjoy your videos! Salute!
As I enjoy your videos too Sir!
@@project-326 👍😊
Non-crippled software would be an improvement. An SDK would be even better.
SKD is a great suggestion...
@@project-326 there is an SDK, I got the document from their website using my product number, it's very likely the same protocol. Can share if desired, just let me know of a contact address.
Haha i truly don't have a lot of confidence that they can write good software. SDK or hardware interfacing open documentation would allow some interesting uses. Someone needs a monitor calibrator? Might turn out better than any other.
@@SianaGearz I also have a fairly low confidence, their core team is basically scientists, what they need to get to market is more engineers. Its the classic start-up problem...
VERY interesting! Instant new subscriber with the bell clicked (I never do that 😮)
You might have explained it in the Little Garden vid (going there right now), but I’d love to hear the details of how they get 5nm resolution out of just a few quantum dots.
I built a crappy version of the little garden based on your tear down from the last video actually. I wanted to get one badly, but figured that it was too difficult so I tried to pull it off. I didn't use the monochrome camera, as I could find one (recently I got one, but haven't done anything with it), that said its quite limited, but was super fun to make. I love these videos, they make you think about products.
OK, so I had a lot of very detailed discussion with the creator of the 'little garden' device. It seems I made a mistake in my original video. He is not buying monochrome camera (that is too expensive, due to the very low demand) but manually cleaning of the Bayer Filter. I have a lot of respect for that guy and will be including a whole segment on him in the next video.
I also tried to build one myself - it really made me appreciate the 'little Garden" device a LOT more. Sometimes, its the journey that is more interesting than the destination...
@@project-326 Cleaning a Bayer filter manually sounds crazy, but maybe you know how he does it?
@@嗯哼-e9x The creator would like to keep that part secret... But I ill be showing a video of the process that he sent to me.
@@project-326 that would explain a lot, haha I spent hours trying to figure out if I bought the wrong camera module. Cleaning the Bayer Filter sounds like delicate work that take a lot of effort. Cant wait to see the process!
Sorry to add more stuff. 1. Use the TLM-2 to check safety glasses for bandpass and attenuation regions. 2. For the big color squatters and even Home Depot: use spectrometer to check
their color patches at the store with the final color of the applied paint to different surfaces. 3. I want to check for UV output for the Chinese made LED bar lamps I use at the desk for bright
white reading source, electronic assembly and soldering and video lighting. 4. Looks like around a 1cm diameter of the input diffuser. When you get sunlight, I am guessing
1316W/m^2 multiplied by 0.00007854 (area ratio) = 0.1068W/m^2 input in sunlight without pollution etc. With CSV data we can do the integration for calibration or atmospheric
effect measurements.
Thanks for all the hard work and I can understand the two week period between videos. It is greatly appreciated. Are the background squares 1cm in your TLM-2 videos?
Inquiring minds want to know.
This is great, the more applications the better, a tool is only useful if it has a job to perform!
I need to check on the mat, I have two, one is 1cm and the other is 1" (I do photography in 2 different locations)...
Great thingy. I hope one day someone makes it available on Aliexpress, or on other international site.
Hopefully this will be on Amazon soon!
Thanks for the in depth review.
It's a very interesting product, it would be much nicer if the apps were had the basic functionality working really reliably. The mobile apps need to find the unit faster and the PC app needs to remember settings.
A USB C socket would be highly appreciated too.
P.s.
Please retire the slow robot voice and refrain from repeating the same information you just said when you switch to the spectrum results.
@@MaxNippard We are hoping that if there are enough comments about the issues, the manufacturer will make the changes...
@@MaxNippard I second the suggestion to retire anything repetitive.
@@MaxNippard How long have they been developing this device ?
Haven't seen a Mini-USB connector for over a decade. 0:07
Nice device. It would be nice to have a machine readable export format. And it would be nice to have higher precision of the small device combined with the finer resolution of the bigger one.
If I had time for that, I'd look into possible hacky modifications. Those devices send their simple data packets over the com part without any encryption. Don think their company would like that approach tho. But that's what happens by making silly decisions the customer has to life with.
Great review and cool device! Looking forward to seeing the second part!
I'd suggest that non-proprietary parts of the user interface software be open source.
The difficult parts are the hardware and any secret sauce they have for calibration and signal processing.
The UI parts where the processed output data is displayed should be open so users can customize it or integrate it with their own tools.
This would also allow users to contribute features and bug fixes back to the official UI project, improving the product for everyone.
Thanks for the ideas, I hope they will be able to take these on board...
If this is just a COM port, surely you can just write translation layer and use something like ArgyllCMS. Or whatever software to your liking.
Edit: Would have liked to see the insides. But I see that coming. Looks like another camera sensor. Would have thought a linear scanner CCD as better, but I guess optics would need to much better then as well as a size increase. Please keep finding these gems.
Edit2: Would you mind testing these for color calibration (I see their software does do something for that with xy coords)?
An important note!! None of the lasers used (besides the green 532nm unit) use a frequency doubling crystal. The infrared lines are artifacts on the spectrometer.
Yep, we will be adding a correction to the part 2 video.
@@project-326 cool, looking forward to seeing it
Like you said, CSV export is pretty important. The other thing I'd like to see is the software being open source so there are no questions about its safety.
I don't think they would release their software open source, but perhaps an SDK is a good compromise...
PEACHES and a Spectrometer Review are two things I never in my life assumed would be together!
;-)
Human music at its finest, in the right setting, of course...
Some of your extra peaks are artifacts of the way these spectrometer works and not actually in the light source. You can confirm this with some filters.
I'll take a look at that in the next part of the video.
Great review! Hope you could mention that most engineering filaments requires an enclosure or even a actively heated enclosure to print, which is not obvious for people who has never printed them.
the infrared peaks on the green laser could be the diffuser heating up
Turns out the IR peaks are from the diode pumping architecture of the laser. I put some errata into the latest video on the 'little garden' spectrometer. That errata is equally applicable for this video.
Excellent video. Thank you. One thing, I think you should put a pure black of an inch just in front of the emitter and the receptor (spectrometer), the objetive is to achieve optical engagement without the reflection of other surfaces, in this case the rubber you use. The emitter projects its radiation on the rubber and contaminate part of the rays reach the recepto. Of course, there are a lot of other variables to control; e.g., vacuum, humidity, distance, air composition, etc., etc., but at least, I suggest, you can control the distance between the tubes. I mean: emitter + 0 mm + 2.54 mm (the output non-reflective tube) + 2.54 mm (air distance) + 2.54 mm (the input non-reflective tube) + 0 mm + spectrometer-receptor. Maybe, maybe not, it would improve the results. What do you think? Anyhow, I just want to thank you for your video; I would love to have that marvellous hardware you can get in China. I would make "gun shape form" or pointer, spectrometer; with a laser telemeter to adjust the efect of distance of the surrounding gases (mostly cases air.) I would make may own typical base measurements to stablish sets of spectrographic data base; as well the corrections due to distance, angle or another variable that would apply. And app and small devise like that would be easy for ordinary citizen usage than other portable radioactive spectrographs. It should be quite use full to very quick draft material checks: canvas, woods, metals, cristal, food, etc.,
This is indeed a fantastic find. Many thanks for the video. I will be at the opening gate to buy one as soon as Amazon has them online.
I want one to measure twilight colorimetry to match a paper I did almost 50 years ago. Was in the process of building a DIY spectrometer, but now
I can relax and await the opening bell for the TLM-2. Another test I'm interested in. Variable incandescent lamp to measure blackbody curve vs
temperature for calibration. Question: Has anyone checked for heating in the diffuser as a possible source for the IR contribution?
Thanks!
Hey Thanks! I didn't realize that this feature was enabled!!!!
Hi so thanks for the cool review! I am interested in maybe using one of these to obtain spectra of meteors coming into earth’s atmosphere. I will wager that the light from the meteor will be too dim for the camera, but I thought I would ask! Thanks again!!
probably too dim and too fleeting, but would be fun to try anyway!
One issue that cheap array spectrometers suffer from is straylight, especially excess signal
In the blue/UV. Grading instruments can have order sorting filters and multiple gratings to eliminate. This one has some filtration on the pixels and a magic algorithm. I’d have done some tests with a broadband source and a thick bit of various schott coloured filters, see if you get any signal where you should see none. You could also check you “higher order effect” hypothesis by filtering the source so there is no light in that spectral region and then seeing if the higher order lines appear.
Calibrated, how, against what and for what sources?
Interesting little device. No numbers out is no sales made. No way to check noise floor, stray light etc. roll on part 2.
indeed. So much is not defined but that only means that there is more to learn...
We NEED people like you to evaluate the few US electronic products as well as EU products to see if feedback can help improve their products too.
so many things to test, so little time...
800-830nm line is the pump diode that drives the 1064nm that gets doubled.
Thank you for the feedback, other have pointed this out too, in part 2 of the video, we will be making some corrections.
I wanted to know more about creation of monochromatic source of light and embodying the same into a Laser! What does the terms ‘Source Wave Length’ and its multiplicand’ means? How the mulltiplication of frequency of light is achieved, in practice?
Very nicely explained and demonstrated! I wanted to look for different lines of emission from pure hydrogen spectra; particularly of Balmer & Paschen series. I wanted to get assured about the same! Or whether we were just tought to be so! Thanks.
That is exactly why I like to make experiments on this channel, nothing beats seeing stuff for yourself, even if the results are way less impressive than from a professional lab. The reason people still buy telescopes is for exactly the same reason, nobody can beat the Hubble of JWST images but those are someone else's results. Seeing a tiny, dim, fuzzy, monochrome image of the rings of Saturn, with your own eyes, beats all of those beautiful on-line images from the pros.
I'm going to look into finding a low pressure H2 tube...
I'd just listen in on the com port, figure out the protocol, and generate the CSV with reverse engineered software. I doubt it's that hard to do.
It's certainly worth trying that, let's hope that didn't try to encrypt the data to prevent that...
@@project-326 I have a different version of their spectrometer, the PJG3, which came with the information regarding the serial port commands and data packets. This may be useful for your purposes. The data isn't encrypted from the looks of it. The document is in chinese, but translation by machine seemed to have worked very well.
Now, I can't actually test it yet because they don't have the pinout for the TTL interface printed or written anywhere!
The PJG3 version has no usb output, but rather a 4 pin serial interface that is completely unmarked and doesn't come with a pinout diagram (nor is it included in the manual for the client interface or for the SDK).
So, I've written to the company just yesterday to inquire about this. Their Alibaba store is offline now, so I had to write to their email.
No answer yet, I sent them a machine translation version a few hours ago, hopefully they'll come through and provide this info.
Cheers!
I am very interested in this device, if it has iOS support and CSV data output!
'Posh' Arthur is actually Brian (text-to-speech), used at "Go Animate".
It might sound a bit like that one, but actually its from a different source.
Wow.. i love it! I still remember using room sized monochromators (25 years ago) with a knob to manually rotate through each wavelength - used to take 4 hours to get a reading!!! Specifically on the device, the physics looks sound! The key thing is to be able to easily get raw data out, have quick analysis, and perhaps upload target spectra to the mobile/tablet. Also if it canbgenerate CIE coordinates, that woukd be great. Finally lower the price, tge more people will use it, but there needs to be a good build quality. I'm looking forward to buying one!
The Sanatorium White led needs a high pass filter to get it closer to sunlight
To the manufacturer: I direly want a spectral analyzer tool. if you add a CSV export OR a CRI rating, I would try to buy it if it is available in Germany. Please add CSV export or CRI measurement
Thanks for the feedback!
CRI would be neat!!!
@@leandroebner1405 That's a really nice suggestion, let's mention that to Torch Bearer as well!
Please add CRI measurement to this product. ❤
Several people have suggested this and I sent a message to the manufacturer. Not sure if they will add this, lets see.
I have that exact 450 nm pointer. It is not a DPSSL, it's direct eiode, so there should be no IR emission. I would suspect the same for the 410 nm, not that DPSSL is impossible, but they would cost more than 10x as much as a direct diode laser. Looking at the spectral width, I am fairly sure these should both be direct diode lasers. You should be able to tell by which way the batteries are inserted, or, you might be able to open them up to see the module.
The 532 nm, however, is indeed, more likely, DPSSL, pumped with an 808 nm IR laser, so that is reassuring... however, the artefacts for the near UV lasers is concerning to me. I'm 98% sure something is wrong with the spectromeret... higher order diffraction or some other interference, rather than an issue with the laser.
Still, though, both products are interesting to me. If they are available in the USA for under $150, I'd seriously consider these. If they go higher than that, they'll already be in competition with other super-low cost spectrometers that seem to have fewer reported bugs.
Yup, if figured that out from some other comments. I will be making some corrections in the next part of the video.
Thank you for the corrections, learning is something I never want to stop doing and having people that know something I don't, point out mistakes in the comments is a positive experience for me.
great. love the style. love the color names.
Thanks so much!
I wonder what the spectrum of various video monitors is. If some are more narrow-band than others, and which are the better ones. We already know or look up common lighting sources.
that is an interesting experiment we might include in part 2 of this video...
Since it appears that this new model has a reflected diffraction grating (im hoping it is surface reflective) and they made their own sensor, im wondering if they could increase the spectral range further into the UV. If that is not possible to keep it in budget, it would be nice to see an affordable model that maybe starts in blue or violet, but can function down to 200 or 250nm.
yes its a surface reflective type...
@@project-326 good! There's hope!
@@jimzielinski946multiple order issues and the fact not much transmits at those wavelengths could damped your hope.
@@peterwoolliams1283 I understand that if they attempt to go into the UV, they have to make sure all the optical components and materials don't absorb UV along the way. I'm thinking about using such a device with microscope illuminators that (they claim) pass UV as short as 250nm. (Some of the quarts lenses I have claim to be rated to 200nm). eBay has been great for finding deals for most of my hobby, though, (working) UV spectrometers are not one of them. Hope is all I have now!!!!
Very interesting product. Hope the mfr make available some tools or libraries to use this on Linux or for integration into other projects
I hope so too
I want to get one as well. Having a CSV data output would be great as well because then we can run in through other applications or just save it in a database for future reference and calibration.
its a definite requirement for it to be useful. such a calculating cie-lab color temperature calculations.
You'll run into a dead end pretty soon when you can't to anything with the data you measured. Agreed. Not a total dealbreaker because that thing in that price range is less a scientific tool and more a fun nerdy gadget
You may need our more professional P4 or P4 pro, tlm2 is only suitable for use, not data analysis
Might you try using the TLM-2 to check if the Little Garden could me used for luminosity measurements?
Yes, that is good idea, to create a calibration curve for exported data from the little garden...
What happens if you remove the diffuser? Might it be possible to attach to a telescope and look at spectra of individual stars?
Inquiring minds want to know. Hopefully you have another after the reverse engineering exercise? Thanks in advance.
I'm not sure how it would be focused down into the slit and how that would affect the measurement.
the diffusor is easily removed, but I that will effect the calibration of the intensity...
Would either of these be useful in discovering the unknown gases and vapors sealed inside a vacuum discharge tube or sealed glass vessel ?
There is a video about exactly that on the channel page!
I was able to get both the spectrometers that you have listed on here and I look forward to trying them out. The TLM2 you mentioned seems to be labeled the P3, and its filed under color illuminance meters, and is good for 340 - 780nm. There spectrometer section has some different models with some higher spectral ranges including a quantum dot spectrometer...curious to benefits of that compared to the model you currently have. I'm guessing the video you are referring to showing the video on this is where you have the ampules of gasses you are looking at? Thats a really cool process that showed me this is possible, but I guess I am wondering if I'm looking at a Geissler tube that has had vapors and gases sealed for over a hundred years, there could have been reactions changing things inside the tube and my wonder is, Do these cover spectral ranges enough to gather data and evidence on such things? or would I need to step up to a wider range on the spectrum? Thanks for your help and great work!!
How does this unit compare the the Changhong H2 mobile phone, which had a spectrometer built in? I cannot find one in my current location, but maybe you could find a second hand H2 and do some comparison tests?
Also, have you seen Jerry De Vos' implementation of an open source plastics spectrometer project?
The cell phone 'spectrometers' just used the AMS sensors that only were able to discriminate a handful of wavelengths, usually less than 10.
@@project-326 _ Were there other Chinese mobiles that includes spectrometers?
Here is a link for Jerry's DIY project.
www.youtube.com/@jerzeek
I would be interested in one of these, but only if the suggested improvements in the video were made, and especially if the software for it was made to be open source. An additional suggestion would be for it to be USB-C compatible.
its using the old Mini-USB because its not USB, but serial UART. There is a USB-UART converter in the cable itself. Hopefully they can improve that too.
With this device and your acumen for naming, Posh-Arthur is certain to be the next successful colour squatter.
I wonder if this spectrometer would be good enough to distinguish between flame from burning methanol and ethanol.
I have no idea, but its a really good experiment to try. Do you know the emission spectra for these substances?
@@project-326 unfortunately I don't. All I could find is that ethanol has more lines due to the fact it's more complex therefore has more paths to burn.
This channel going to blow up.
Indeed. And I'm incredibly happy RUclips gained another good channel for informative science
There should be CSV output, but I wonder if the pdf might be able to be "read" by Chat GPT which would output what it "saw" in your format of choice? Edit: I just tried it with Claude and it told me that the resolution of the chart I gave it wasn't good enough for accurate reading. I'd like to see the PDF output of this instrument. If high enough resolution it may work.
Cool! Are there any miniature NIR or MIR spectrometers in a similar form factor?
Regarding the green laser: The small IR peak is from the IR pumping diode which then goes through two crystals which do the frequency doubling, etc. This green laser appears to adequately filter out the IR but many do not. Edit: You mention this with the violet laser. I see this video took a while to put together, LOL
Thank you, I have already be 'educated' in that aspect by another kind viewer. The thing I like best about making these videos is that there are always people with more knowledge to learn from. I didn't realize that the green laser was a 3 stage process. Its amazing how much technology can be crammed into a $10 laser pointer...
@@project-326 They're cheap as chips today but i remember when green pointers cost the earth in the earliest days of the internet. BTW, they now make fully SS 488mn blueish-green ones with just the diode - I own one. I need to develop my own YT channel with all the tech junk I've accrued over the years. LOL. I'm glad you welcomed my earlier explanation on this public forum and I'm certainly learning a lot from your good self. Can't wait for the second half.
@@project-326DPSS are nowadays some of the cheapest lasers which is crazy when you think about how complex their optical path actually is
@@DennisSantosyes please. RUclips needs more creators in that field, always!!
@@leandroebner1405 I was one of those that worked on early CD player technology, the whole CD mechanism and OPU ended up costing less than $1.50 in serious volume, in particular the Sanyo DA11 was just an amazing piece of optical technology for its time that somehow also had the distinction of costing the same as a candy bar... If that same technology had been developed for the military, each CD mechanism would have cost about $150K...
Where can I get the LED test bulbs you used? I looked on aliexpress for glass tube led color, but not find anything. Thanks.
I got mine on TaoBao, but that is only available in Mainland China. I found some similar ones on AliExpress using search terms that included USB, but they were just similar and not identical. Sorry, lost that link...
Fantastic video Thanks a lot! Have you tried doing any absorption spectra?
We are looking at 'maybe' doing some raman spectroscopy, but that depends on the costs involved. We have been also doing some experiments with the spectra of various plasma. We might be able to think up some interesting experiments in that area if we get time.
wouldn’t mind buying if it is a little better I am interested in different light colours
I’d be interested in seeing flame tests of some chemicals just for variety. Not table salt, but something more complex. I could see buying one of these when they have CSV, although I don’t need it.
Almost everything I own, technically, I don't NEED.
hey i'm looking for a setup to measure the elementary composition of a substance. how do i do this quickly and easily?
We recently did a video about achieving this using beta back-scattering. Please take a loom on the channel for that one.
Besides resolution, an issue of spectrometers using webcams is that the gain (amplitude) in various channels is not constant, due to processingin the webcam algorithm, so different spectra cannot be compared. Is this using a constant gain, so that I can calibrate and get good results? Without a calibration and constant gain, the spectra are useful only for looking at them, you cannot even measure the CRI of a LED light.
And what about the Garden spectrometer?
The TLM2 isn't using a webcam. They are buying a monochrome CMOS die and getting the QD's deposited onto the sensor directly before the passivization is added. I'm guessing that they are getting the image sensor vendor to do this for them in the fab as a custom version. The TLM2 appears to be pre-calibrated for level and that cannot be changed.
The little garden device will suffer from the issues that you mention, the levels for each of the color channels will be optimized for the 'best picture' for human eyes, not best optimization for photon energy. These types of sensors usually have some OTP ROM that allows the product level manufacturer to set up the color balance, the gain transfer function, etc and those settings will have already been burnt in before the creator of the LG device received the camera module.
The creator of the LG device has released that on AliExpress and there is a link to the store in a post in the community section of this channel.
Pt 2? Also, can you confirm of this is the same product on Amazon now? Idk if it's worth the hiked price at $120
Part #2 is in progress, it is the next video scheduled for release.
It needs a notch filter and csv output. I wouldn't buy it without both of these features.
A reasonable software in English is a prerequisite for international marketing.
Is it so difficult to remember the language and the COM port?
Is it that difficult to install a usable image export?
Exciting. I want one but can't find any place to buy it. A link to where you got yours would ne nice
As mentioned in the video, it isn't available in the west yet, but the company is planning to release on Amazon soon (part 2 of the video is planned for when that happens).
I added the TaoBao store details where I got this product from to the video description, but this only works from China...
Can this be used analyse the composition of metal by sparking and then analyse the colour of the spark in a metal foundry environment
well, in theory yes, but in practice, probably no. The problem is that this device needs a fairly stable light source for several seconds, so a brief spark wouldn't give a result.
I hope that helps!
@@project-326 Thankyou very much.
Brilliant video and product. I’d argue that they are locking out the CSV export whilst they figure out the business model. There’s maybe 2000 one off spectrometer hobbyists who’d buy this for home use and that’s the market done. I’m in already. However if you integrate it into another mass market volume product such as a vehicle or specialised lighting product then your market becomes scalable. I’d reckon that’s where this is headed.
Thank you for the comment. Some of my own thoughts...
Each time I use this device, I seem to find a new application. For example, our IR chroma-key video, it was useful for seeing how spectrally pure a commercial green screen actually was (answer, not very). Amateur film makers will find this useful and because of the low cost, photographers can now have a much better tool than the 3 color sensors that are normally used. Anyone involved in pro lighting is also a potential customer. Basic class room education is also opened up, instead of a high school having one $2000 system to share between all classes, there can be more devices available. Anyone involved in the print and finishing industry, QA technicians and product designers. The list just gets longer each time I think about it...
This device has earned a valuable place in my work bag, I am really strict about what I carry around but its really useful for far more things than I ever imagined.
As for the company, as a tech start-up, their core team are basically scientists and PhD's, so I hope that they can get the help they need with the product marketing going forward.
Does ionizable radiation make the florescent coating on LEDs glow? what is the strength of this ionizable radiation? Can florescent coated LEDs visually indicate the presence of fallout? Assume they had these LEDs in Pripyat will they see unpowered glowing LEDs?
Also does ionizable radiation damage the florescent coating?
Another question. Since florescent material degrade with time will florescent coated LEDs lose their color after decades?
Well that's a good few questions...
OK, so fluorescent materials are used as scintillation crystals in devices like gamma ray spectrometers, but each type of fluorescent material has different wavelengths that it will be excited by. I would doubt that the materials used for LED production would be useful for gamma rays.
Another issue is the number of photons. gamma rays have a LOT more energy per photon, if you had a gamma ray source that emitted the same number of photons as just a small LED, you would basically have a death ray on your hands! Because the number of gamma rays photons is pretty low in the background, gamma ray scintillation crystals need to be connected to detectors that can be sensitive to just single photon events.
Radium watch dials, for example, lose their luminosity in a few decades as the fluorescent material crystal structure becomes damaged by years of alpha particle bombardment, and stop glowing. The dangerous thing about that is that the Ra-224 has a half-life of about 1600 years. People often think that dials that no longer glow are no longer radioactive which can lead to some poor decision making in the disposal of the dials.
I would assume that there will be a small amount of similar damage by a 450nm blue photon on an LED flourescent coating, but given that the energy of a photon at these wavelengths is about 10^9 times lower, I would assume that the damage would accumulate a billion times more slowly.
¿Y el Sol brilló por su ausencia?
And the Sun shone by its absence?
Subscribed for the Peaches bit alone.
I love your channel and just wanted to make you aware I prefer long fourm videos. Making the videos shorter trims out your humorous side and the depth of the information provided.
Thanks for the tip!
Hi any update on when this will be available on Amazon?
not yet, I will send a message to them on Monday to see if they can give me an update.
Thanks for the reminder.
@@project-326 hi did you already send a message to them?😅
@@electrobus5095 Every week...
I am making a new video that includes this device and I am going to include a segment that will encourage viewers to bombard their email address with requests to buy this device. Hopefully they might finally believe that there is demand for this outside of China!
Thank you for an illuminating video - subscribed, liked, and hungry for more.
Welcome aboard!
Would be nice if there was an option to use it like a camera: snap timestamped spectrogram data to an SD card and look at the plots or csv afterwards. (Even if it had to be powered by USB)
the PC and smart phone apps for the TLM-2 device do exactly that, it save a PDF with the spectrum and key data on the measurement.
Thank you for the great review. I am interested in the glass tube LEDs in that you used - please share the source 🤓
I got them from TaoBao (only here in China) but sure that AliExpress or other source will have them. They are pretty cool...
I ordered the little garden from China after saw you video - its working surprising nice. Also I prefer you keep the robotic voice instead of real human voice 😆😆
From TaoBao directly?
@@project-326 Yes, taobao official cainiao shipping service. Cost is very low and deliver within 2 weeks for the economics one
@@project-326 Also want to add that I ordered KC761B the same way as well. Works wonderfully too
@@project-326 For some reason youtube keeps deleting my comment..do you have email that I can contact you directly?
So, what are you, Max Headroom's brother or something?
Pretty cool gadget, If I needed one, I would probably buy it.
What is the maximum power of a laser diode that can be used?
That is not an easy answer to give, it depends on the bandwidth of the light source and the area of the beam cross-section.
The TLM-2 is rated with a 10-10000 lux range. For example, a 555 nm laser beam (FWHM = 1nm) with 10mm2 of beam cross-section would result in a maximum power of about 1W. If the energy is spread over the typical spectra of sunlight, then the device range will be limited to about 2.196 mW.
If it has diffraction grating, why does it need quantum dots?
because of the very short optical path, the resolution would be terrible without the QDs. Your question was a really good one and perfectly valid, so I sent your question to the manufacturer, here is their response:
"The reason we utilize both is that either of them can not provide enough resolution solo. The QDs we synthesized have too broad absorption bands to resolve the spectrum with high resolution and wide wavelength range. The same thing happened to the diffraction grating due to the small size of the device we try to achieve. Then we decided to combine the two techniques, and got amazing results."
Is this sensitive enough to calibrate displays with?
it should be, it gives a pretty large result when placed against a display that is white.
I hope that helps!
I would be interested by the TM2 however no access to the data no purchase! put an open-source software on it pls. Finally the mini USB plug is outdated. Cables start to be harder to find.
I think they chose a mini-USB because it is now just a USB cable, it is the USB-Serial converter and people are less likely to plug in a standard USB cable buy accident. At least that's my conclusion...
@@project-326 I'm not sure to fully understand. usb to serial you normally plug it to a normal usb port on your computer it work with usb-C as well all Arduino like stuffs use that no issue. Now if i have to understand that they use a mini usb plug for a different purpose than usb that is a drama guaranteed recipe as someone will end plugging this in a computer usb plug generating a magic smoke emission.
I just found it on aliexpress, a few left and about $75 delivered to USA.
Ooops, Little Garden not TLM-2. I ordered the former, hope to see the latter soon!
Yes, I hope that they can fix these deficiencies. I'm interested in purchasing a low-cost spectrometer; I have a product I'm developing that I need a tool such as this to explore the light sources I plan to use in it! Upfront: The Functionality and Price will be determining factors in my purchase decision. I agree with the criticism about the software's abilities, they need to be improved. Please, do spend some more time to polish it up before releasing. Even the ability to connect to that 3rd party's open source software might be a good way to get it there, just a suggestion.
I think it is wonderful to have an opportunity to communicate and be part of the community that helps shape the product's we use! And for the manufacturer, it must be a great opportunity for you to get direct and useful feedback by the customers.
In any event, I'm looking forward to part 2 and see if we made a difference. Thanks a bunch!
yes, I am hoping that the manufacturer will be responsive too. What I really like about this unit is the size. It now lives in my work bag on a permanent basis...
You are wrong for 405 nm laser. It is InGaN laser meaning there is no way IR can be generated. What you see is second order peak from the grating. Spectroscopy basics.
Yes, we figured that out in the end, we will be adding a correction to the next video.
Thanks for the feedback.
@@project-326 sorry for the harsh comment. You guys do a great job. PS. I am a material scientist, you can ask me something
The potential of this product is evident, but the manufacturer needs to enhance its software and address any issues. They should strive to create a highly marketable product, where the design and features are of utmost importance. Integrating AI capabilities into the software could take the product to the next level.
Where can I get some of those LED bulbs featured?
Perhaps they are available on other markets? AliExpress, DHGate, etc. what is the brand or model of the LED bulbs?
These aren't exactly the same, but similar...
www.aliexpress.com/item/1005006768029309.html?spm=a2g0o.productlist.main.21.7489zyZpzyZpq5&algo_pvid=9c8238f8-6e27-4510-8a7e-5fac01281b6a&algo_exp_id=9c8238f8-6e27-4510-8a7e-5fac01281b6a-10&pdp_npi=4%40dis%21USD%217.19%215.18%21%21%2152.17%2137.56%21%402167359c17198154480454097eb4e2%2112000039994356366%21sea%21HK%212881401294%21AB&curPageLogUid=boPe8mK5GVRW&utparam-url=scene%3Asearch%7Cquery_from%3A
Clever device, good video. Pity about the software. If the user interface is that bad, no user will want to use it. It would be well worth it to the manufacturer to improve the software.
I'm hoping that they will make some changes...
Thanks, very thorough video. But there is one thing that annoys me: the glass breakage sound after the titles.
I try different experiments in each video for the chapter titles, the results are not always ideal.
Thank you for the feedback!
Definitely needs a way to get the data into other software--like csv file output.
But with that, the company I work for would buy several of them.
Nice comment! I hope that sinks in with the manufacturer!
This kind of affordable spectrometer is really useful for lighting designers and others invo!ved in architectural lighting design for confirmation of product specification. Also increasingly important in other areas of professional lighting such as photography and videography. So far the product seems pretty good for our kinds of use with sufficient resolution and accuracy. Typically the output format in PDF isOK if we have enough detail and refencesto ISO and CIE standards however CSV is necessary For calculating colour fidelity and also for melanopic effectiveness through standard tools freely available from IES and CIE. Price in the market is also important as will be thelevel of calibration against traceable standards to NIST or other international standards. Also how about recalibration? If it is cheap enough and calibration from new is warrantied for say 2 years then replace that would be good enough if the unit is cheap enough. Currently I need to replace my existing spectrophotometer as the company who made it are out of business and it cannot be recalibrated also there is no software support for it
These are all really good questions that I hope the manufacturer will be able to have answers too!