Optical Design of LCOS Optical Engine and Optimization With Genetic Algorithm

This paper demonstrates an optical design of miniature of LCOS optical engine and optics with white light-emitting diode (LED) and the most importantly, proposes a new optimization method for non-image optics via Genetic Algorithm (GA) written in Optical Software ASAP, in order to achieve best performance for light efficiency and uniformity. Thanks to the development of modern digital equipment, optimization work for non-image optics plays a role in modern optical engineering. So far Least Damping Square, Taguchi Fuzzy, and simulation annealing methods have been introduced and some of them has been applied to many items of commercial simulation software. However, GA is first introduced in this paper for non-image optical design and optimization, although it has been for many years been used as effective optimization method in image optics; In this paper, GAs are written in the form of macro language from ASAP. During the design process, we used one OPTEK Technology OVS3WBCR44 LED as the light source of the general projection display. Because of the extensiveness of the LEDs, the collection efficiency within the desired acceptance angle was not expected to be high. Due to the particular acceptance angle (cone), we needed a condenser lens system, which satisfied the light small angle incident to 0.59-in liquid-crystal-on-silicon (LCOS) pixels. The optical engine in this paper is designed for a compact LCOS projector with a white LED light source and the employment of an LCOS panel has been reduced to one piece in order to get the best volumetric size. Optical design specification is mainly for an 11^" projected screen, whose objective distance is close to 420 mm with fixed focal lens. GA methods are applied in this research in order to achieve maximum brightness and uniformity. Compared to traditional optimization methods, such as Least Damping Square, the GA used in this research gives reasonably good results.