Chapter 17.2, Problem 30SSC

To determine

To explain: Whether the spherical aberration be less or not.

Explanation of Solution

Introduction:

Spherical aberration is a kind of aberration observed in an optical system which uses spherical mirrors. The light rays that incident on the outer edge of the spherical mirror are reflected or refracted more or less compared to that incident close to the central portion of the spherical mirror. Due to this deviation in reflected or refracted light rays, the image produced by an optical system which uses a spherical mirror is of less quality. That is, the image produced is slightly blurry.

The spherical aberration is less in a mirror with height smaller than that of its radius of curvature. Because at this circumstance the light rays diverging from an object that strikes the mirror are closer to the optical axis of a mirror. Hence, the reflected or refracted light rays converges more closely and produces an image which is not blurred.

Conclusion:

Therefore, the spherical aberration is less for the given specification.