Optical system for stereographic projection

Abstract

The invention relates to an optical system for stereographic projection. The optical system for the stereographic projection comprises an object image, and a projection objective lens or a projection objective lens. The optical system further comprises a color splitting prism. Light beams which are emergent from the projection objective lens or the projection objective lens pass through the color splitting prism to be split into a green light path, a red light path and a blue light path. The light beams in the green light path are polarized by a green light polarization beam splitter, and finally two sub light paths in the same polarization state are output. The light beams in the red light path are polarized by a red light polarization beam splitter, and finally two sub light paths in the same polarization state are output. The light beams in the blue light path are polarized by a blue light polarization beam splitter, and finally two light paths in the same polarization state are output. The six sub light paths are polarized and modulated into left circular polarized light and right circular polarized light by a liquid crystal variable phase retarder in the synchronous time sharing process. According to the optical system, more than 97% of energy of natural light can be polarized into linear polarized light after color separation, and therefore the picture brightness and the stereographic display fidelity can be greatly improved.

Description

technical field [0001] The invention relates to the field of 3D stereoscopic projection display, and more particularly relates to a color separation polarization beam combining zoom optical system for stereoscopic projection. Background technique [0002] With the 3D stereoscopic movie "Avatar" being screened globally in 2009, and the popularity explosion of "The Twilight Saga: Lunar Eclipse", the 3D craze has been heard in a wide range of the world. At present, most theaters support 3D playback. DLP (Digital Light Processing) projectors with Texas Instruments DMD (Digital Micro mirror Device) as the display chip are used in most theaters. Since the light source used is a xenon lamp, the light emitted is natural light, that is, the polarization state is randomly generated, and to realize stereoscopic display, it needs to be polarized into linearly polarized light, and then a Liquid Crystal Variable Retarder (Liquid Crystal Variable Retarder, LCVR for short) modulates it, an...

AI Technical Summary

Problems solved by technology

[0003] Since the projector continues to play the picture, that is, more than 55% of the emitted light energy will continue to be absorbed, reflected and scattered by the polarizer, which will cause the polarizer material to absorb a large amount of light energy and cause temperature rise, and its polarization degree and other properties will be reduced, or even damaged.

Moreover, the general polarizer will be attached to the surface of the liquid crystal variable phase retarder, which will cause the liquid crystal molecules in the liquid crystal cell to absorb most of the heat, and the liquid crystal molecules are very sensitive to temperature, which will affect their birefringence coefficient , causing the optical path difference of its polarization o and e light to change or even fail, which in turn affects the stereoscopic picture effect displayed on the screen

[0004] Due to the energy loss of more than 55%, in order to increase the display brightness, the theater will use a higher power xenon lamp, which greatly increases the cost, and the higher power of the xenon lamp will cause more energy to be absorbed by the polarizer, making the polarizer and liquid crystal Boxes are more prone to damage

The sharp decrease in the parameters such as the degree of polarization of the polarizer will intensify the crosstalk between the left and right eyes, and the 3D stereoscopic display effect will be greatly reduced, which will fall into a vicious circle.

However, if the power of the xenon lamp is increased, its life will be greatly shortened, the theater will replace the xenon lamp more frequently, and the operating cost will also be greatly increased.

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