Extended depth of field with a nonlinear silver-halide emulsion detector

Presented here are experimental results of an extended depth-of-field (EDF) system using film to record the image. The EDF system used is an application of wave-front coding. A phase mask is placed in the aperture stop of the lens to code the image data; then digital signal processing is used to decode the image. Wave-front coding is based on linear systems theory, but film is not a linear medium. An extra step of linearization is then needed to apply the technique. Both nonlinear and linearized results are shown, as is a test image that demonstrates the success of the technique for nonlinear media.