Surfaces of a thin equiconvex glass lens have radius of curvature R. Paraxial rays are incident on it. If the final image is formed after n internal reflections. Calculate distance of this image from pole of the lens. Refractive index of glass is μ.
The rays will first get refracted, then n-times reflected and finally again refracted. So, using
for first refraction, we have
For first reflection let us use
