How to inscribe a Fiber Bragg Grating?

In our Photonics lab at the Institute of Microwaves and Photonics (LHFT) we are able to inscribe our own Fiber Bragg Gratings (FBG) using an Excimer laser and the phase mask method. In this video, we would like to invite you to our lab und teach you the basics of the inscription process.

[@w8ryanb]

Thanks for the video. It's hard to find good videos likes this that show the implementation of advanced techniques.

[@naveed3619]

Very nice video. I am wondering how CFBGs are made. I guess the method would be the same, only mask changes ?!

[@MachiningandMicrowaves]

Is there a physical effect of inscription that causes the shift in the peak wavelength after the second set of exposures to the laser at 10:50 ? Very interesting video, many thanks for sharing this.

[@instituteofmicrowavesandph2740]

The peak wavelength (or Bragg wavelength lambda_B) is shifted after the second inscription step, because the effective refractive index n_eff changes due to longer exposure to the UV beam. The equation for the peak wavelength as shown in the beginning of the video: lambda_B = 2*n_eff*grating period.

[@ananharomae3575]

I have some question for FGB that i found issue about reflectivity as shoot laser to fiber optic. I use center wavelength 973.6 nm. I have confirm check the laser and alignment but can’t fix yet. Do you have any advice to action for this.