Optical System and Assembly Method

Abstract

An optical system which includes some or all of the following parts: a laser light source which illuminates a spatial light modulator such that optical characteristics are preserved; a stereoscopic display which has a polarization-switching light source; a stereoscopic display which includes two infrared lasers, two optical parametric oscillators, and six second harmonic generators; two light sources processed by two parts of the same spatial light modulator; a method of assembly using an alignment plate to align kinematic rollers on a holding plate; an optical support structure which includes stacked, compartmented layers; a collimated optical beam between an optical parametric oscillator and a second harmonic generator; a laser gain module with two retroreflective mirrors; an optical tap which keeps the monitored beam co-linear; an optical coupler which includes an optical fiber and a rotating diffuser; and an optical fiber that has a core with at least one flat side.

Description

BACKGROUND OF THE INVENTION[0001]Movie theaters have traditionally relied on projectors which use an arc-lamp as the source of light. This is a highly inefficient source for projecting an image onto a screen due to the extended size of the source, its low brightness, its broadband light, and the relatively short lifetime of the lamp itself. The cost of ownership to theater owners is large due to the frequent lamp changes required, the cost of electricity to operate the multi kilowatt lamps as well as the cooling required to keep the projector room at a normal operating temperature.[0002]The move to digital cinema further reduces the efficiency of the lamp due to the requirement that the light needs to be separated into component red / green / blue bands to illuminate three modulation arrays in a uniform manner before recombining the beams for projection. Finally, 3-D digital cinema requires even more light as the projected image must be alternated between scenes for the left and right e...

AI Technical Summary

Benefits of technology

[0012]In summary, the main problems facing digital image projectors are providing a bright image with a long operation lifetime, especially in the case of stereoscopic systems, and providing an alignment and assembly method that is feasible in full-scale production.

Problems solved by technology

This is a highly inefficient source for projecting an image onto a screen due to the extended size of the source, its low brightness, its broadband light, and the relatively short lifetime of the lamp itself.

The cost of ownership to theater owners is large due to the frequent lamp changes required, the cost of electricity to operate the multi kilowatt lamps as well as the cooling required to keep the projector room at a normal operating temperature.

The move to digital cinema further reduces the efficiency of the lamp due to the requirement that the light needs to be separated into component red / green / blue bands to illuminate three modulation arrays in a uniform manner before recombining the beams for projection.

Solid-state lasers are not without problems, however.

The typical high purity TEM00 Gaussian spatial mode is difficult to convert to a uniform source over the digital modulators.

The narrow line width of a laser leads to speckle patterns over the viewed image which may lead to an unacceptable loss of image quality.

In manufacturing quantities of thousands or more, conventional optical assembly techniques do not provide cost-effective methods for assembling optical devices with high tolerances such as complex laser systems.

In summary, the main problems facing digital image projectors are providing a bright image with a long operation lifetime, especially in the case of stereoscopic systems, and providing an alignment and assembly method that is feasible in full-scale production.

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