Question

A contact lens has a convex and a concave side. The radius of curvature of the convex side is 1.5 cm. The radius of curvature of the concave side is 1.6 cm. The lens material has an index of refraction of 1.7. What is the focal length of the contact lens? (in cm] Answer: What is the optical power of the contact lens? ſin D] Answer:

Answer 1

Convek side Concave - Sicle from the Lens Maker. formula, we know, ta (4-1) ILI - L R R₂T Where Me Refractive index of material Now, for Convere side, R = tve for concave side, R2 = tve. Thus, --- = (1.7-1) [ts til = = 0.* (1635) (1.5*161 1 f 1.5 x 1, 63 34.29 cm 0 + 80: | Focal length of the contact lens will be f = 34:29 cm The optical power of the contact lens.. F in metres) 0.3429 m _= 292 D