Spherical Refracting surfaces

# Spherical Refracting surfaces (S.R.S)

These are the refracting surfaces whose curved part is the part of a sphere.

Types of S.R.S

(i) Convex S.R.S

(ii) Concave S.R.S

Terms about S.R.S

(i) Pole (P)

(ii) Centre of curvature (C)

(iii) Radius of curvature (R = PC)                             

(iv) Principle axis (line joining P & C)

ASSUMPTIONS:-

(i) The object is a point lying on the principle axis.

(ii) The aperture of refracting surface is small.

(iii) Incident and refracted rays make small angles with the principal axis.