response to a binary signal is inherently linear and no improvement is

possible with predistortion.

 In display holography, non-linearity does not play an important

role. The harmonic terms are diffracted at broad angles and do not

significantly affect image quality. In fact, because of increased

efficiency, most display holograms are purposefully saturated. In a

hologram for use as a matched filter, the linearity is very important.

The harmonic terms contribute to noise and loss of efficiency. Even

though some efficiency is gained by driving the film into saturation,

light is diffracted to higher orders and this light is lost to the

system. In an optical correlator with limited light budget, this loss

may be intolerable. Such a system is the prime candidate for the

advantages offered by the CGH utilizing computer linearization.

Computer linearization is a vital step in optimizing the continuous-

tone CGH matched filter.