In
optics,
chromatic aberration (CA, also called
achromatism, chromatic distortion, and
spherochromatism) is an effect resulting from
dispersion in which there is a failure of a
lens to
focus all
colors to the same convergence point. It occurs because lenses have different
refractive indices for different
wavelengths of
light. The refractive index of transparent materials decreases with increasing wavelength in degrees unique to each.