Kohei Teramoto

46.2: Optical System of Ultra‐Thin Rear Projector Equipped with Refractive‐Reflective Projection Optics

An ultra-thin DLP™ rear projector composed of a refractive-reflective projection optics and an off-axis hybrid screen has been designed. The projection optics has extraordinarily large projection angle of 136 degrees with very low distortion, which is also applicable for a video-wall monitor as well as a stand-alone display. Results of prototype projection systems using the technology will be presented.

Refractive-reflective optical system for realizing an ultra-thin rear projector

— This paper presents a new optical system used in an ultra-thin rear projector with a 1500-mm diagonal size and 260-mm depth. A refractive-reflective optical system was developed to achieve a large projection angle of 136° with a small optical distortion of 0.1%. The optics consists of a convex aspherical mirror and a refractive lens. In addition, a new Fresnel screen composed of hybrid blades of refractive-TIR (total internal reflection) elements was developed to attain good uniformity of brightness and color within the image area.