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Introduction to Conrady chromatic aberration coefficients

It is rarely the case that chromatic effects can be ignored when designing a lens. To evaluate the lens performance, the Conrady "dee minus dee" method is often used. This method allows the chromatic aberration of the lens to be evaluated by tracing a paraxial chief and marginal ray.

Definitions

The "dee minus dee" Conrady aberration coefficients are denoted (notation of Kidger)

C1 Axial color
C2 Lateral color

These are defined to be twice the wavefront distortion associated with the aberration. The wavelength interval used for calculations is the range present in the waves table.

Optimization

The (paraxial) Conrady chromatic aberration coefficients are accessible via the merit function editor. This allows optimization in an efficient manner.

See also