What is a Contact Lens Base Curve?

DeliverContacts.com and Your Eye Show host, optometrist Dr Ed Wallington, explain what the contact lens parameter “Base Curve” actually is. Go to Your Eye Show for education about “all things eyes” and DeliverContacts.com for ALWAYS LOW PRICES on top brand contact lenses. #BaseCurve #Diameter #power #NearSighted #Farsighted #DeliverContacts.com #YourEyeShow #Eye #eyes #eyeeducation #optometrist #20/20 #vision #retina #cornea #lens #floaters #glaucoma #maculardegeneration #optometry #optics #focus #nearsighted #farsighted #astigmatism #presbyopia #contactlens #Acuvue #Oasys #Max #Multifocal #Moist #Alcon #Dailies #Total1 #CooperVision #MyDay #Energys #Biofinity #Toric #BauschandLomb #B&L #Infuse #Biotrue #Ultra #Precision1 AirOptics @Hydraglyde #Hydraclear #Myopia # Hyperopia #Hypermetropia

[@RaijinTheGreat]

funnily enough, doctors in austria dont tell you this value!

[@ironwithin3875]

Why is the diameter of a cl not equal to the (base curve x 2)?

[@YourEyeShow]

The diameter of a contact lens is not a perpendicular representation of the curve like base curve... Instead, it is a horizonzatal edge to edge measurement of the lens. Think of it this way, a contact lens is not a complete semicircle, like a sliced half of a bubble. If it were, you'd be right, half of a bubble would be twice the radius wide... a contact lens, however, is more like a one-third slice of a bubble, it is less... reiterating, if a contact lens was a semicircle, the you're right, it would be BCx2... So if you lay a contact lens down on a table and measured it with a millimeter ruler, you would find a lens diameter. For example, the cornea of an eye is about 12mm wide, and a contact lens is fit so that it has 1mm overlap on both sides would be 12mm + 1mm + 1mm = 14.0mm. Thank you for the question.