Effect of Surface Error Distribution and Aberration on Electromagnetic Performance of a Reflector Antenna

Table 4

The Seidel aberration in terms of Zernike coefficients.

Aberration	Polynomials	Magnitude	Angle	RMS
Tilt
Focus
Astigmatism
Coma
Spherical

Note: the sign of the magnitude of the focus term is chosen to minimize the magnitude of the coefficient, and astigmatism uses the sign opposite that.