Performance estimation of projection display system using a diffraction-based liquid crystal spatial light modulator

摘要

The basic performance of a projection system using a diffraction-based liquid crystal spatial light modulator is studied. First, the relationship between the modulation pattern of light at the SLM and its diffraction pattern is analyzed using the scalar diffraction theory, and anew method for improving the contrast of the projected image is proposed on the basis of this analysis. Then, the optical efficiency and image contrast are estimated by numerical calculations, in which monochromatic illumination incident on the SLM at a certain angle range is assumed. Both an efficiency of 0.65 and a contrast of 200 are obtained at the same time by optimizing the modulation pattern and apertures in the projection optics. The possibility of realizing a projector delivering bright images with a high contrast is suggested.