Q. A spherical aberration in a thin lens can be reduced by
Ray Optics and Optical Instruments
Solution:
Spherical aberration is caused due to spherical nature of lens. Paraxial and marginal rays are focused at different places on the axis of the lens. Therefore, image so formed is blurred. This aberration can be reduced by either stopping paraxial rays or marginal rays, which can be done by using a circular annular mark over the lens.