An Acousto-Optic Tunable Filter and Digital Micromirror Device Based Projection Display System

The digital light processing (DLP) technology has made significant inroads in the projection display devices to create high quality images. In this paper, an acousto-optic tunable filter (AOTF) based DLP projection display system is introduced. This new DLP projection system uses an AOTF to replace the rotating color wheel or prism in the traditional DLP systems. As the AOTF can filter out any monochromatic light at a certain wavelength from 400 to 800 nm, more colors can be modulated by only one digital micromirror device (DMD) chip and more color gamut can be got. The AOTF based DLP projector offers the advantage of having no rotating parts and can switch the color at very high rates, which can avoid the “rainbow effect” and makes the new system more simple, reliable, and cost effective.