Lens Design Fundamentals, 2nd Edition

Chapter 6

Spherical Aberration

It was discussed in Chapter 4 and illustrated in Figure 4.5 that the field-independent astigmatic aberration comprises defocus and spherical aberration. This means that they are not functions of field angle and are constant aberrations over the entire field of view, and that collectively they are a function of the odd powers of the entrance pupil radius ρ for the transverse aberration form; that is,

$\underset{\text{Defocus}}{\underbrace{\rho }}+\underset{\text{Spherical}\text{Aberration}}{\underbrace{{\rho }^3+{\rho }^5+{\rho }^7+\cdots }}$

In this chapter, we will consider both defocus and spherical aberration. In Section 4.3.1, the transverse defocus in an image plane located ξ from the paraxial image plane was shown ...