Application of a self-learning controller with continuous control signals based on the DOE-approach

An apparatus for generating patterned images which are variable in color contrast and spatial frequency while retaining a substantially constant, uniform level of photometric luminance. Two broad spectrum beams of luminous energy are individually projected through two orthogonally oriented polarizers and interleaved upon being split. The intensity in one beam is homogeneous while the other contains a spatially periodic pattern. The two beams created by splitting and interleaving are selectively color filtered and combined after one is translated sufficiently to reverse its phase relative to the other. A rotating polarizer in the path of the output combined beam alters the pattern color composition between one extreme where the spatially reversing colors are defined by the color filters and the opposite extreme in which the pattern disappears into a uniform composition of the two colors.