Rear projection forma stereoscopic vision projection television

摘要

PURPOSE:To improve the stereoscopic feeling of a video by using such a Fresnel lens sheet that the mean birefringence in the plate thickness section of the Fresnel lens sheet satisfies a specific condition. CONSTITUTION:The subject projection television is constituted by using the Fresnel lens sheet 2 whose mean birefringence n in the plate thickness section satisfies expression 1, where (t) is the thickness of the Fresnel lens sheet 2, lambdais the wavelength of light transmitted through the Fresnel lens sheet 2, and theta1 is the angle of refraction after the incidence of light on the Fresnel lens sheet 2. Consequently, the polarization deviation of image light 3 which is already polarized due to the birefringence presenting in the plate thickness section of the Fresnel lens sheet 2 constituting a screen can be suppressed below a specific value as a phase difference, so the video light 3 which is polarized circularly to the right or left or polarized horizontally or vertically so as to obtain a stereoscopic video can be projected on the screen. Consequently, the video which provides stereoscopic feeling can be observed.