Saturated laser Fourier-amplifier as a source for half-tone images in laser projection

Abstract

A contradiction between high efficiency of an amplifier operating in a saturated mode, and nonlinear distortions in image reproduction characteristic for this regime is solved. A lasing medium is located in a Fourier-plane of the image, its gain profile being specially shaped, while the amplified image is illuminated by a laser beam which angular divergence is appropriately formed. Criteria for the gain shape and beam divergence are formulated. A possibility for correct amplification of binary and/or half-tone images with high efficiency of energy stored in the laser medium (up to 70%) is shown. The results are applicable for laser image projectors of systems of virtual reality, simulators, etc., providing images with high dynamic range (e.g., pictures of illuminated landing stripes, approaching car lights, etc.).