DLP zooming projection lens

Abstract

This invention relates to a kind of DLP varifocal projection lens. The main character is that: the optical system is made up of the focusing group U1 with the negative power and the varifocal group U2 with the negative power and the compensating group U3 with the positive power. The U1, U2 and U3 are arrayed along the light axis from the screen side to the plane. The focusing is reached by moving the U1 group which has the varifocal function, which is reached by moving the U2 and U3 from wide-angle end to telephoto end, the lens is the asynchronous varifocal system. The lens is the sphere lens. The process is good and proper for batch production; also it has the merits of compact structure and low cost.

Description

technical field [0001] The invention belongs to the technical field of optical appliances, and is a zoom projection lens suitable for use with a non-telecentric illumination light path on a DLP projector. Background technique [0002] DLP projection display technology has developed rapidly in recent years, and its development trend is to realize large-screen, high-definition, high-brightness image display on a short projection distance, and it can realize product features such as small size and light weight. The core component of DLP technology mainly adopts DMD digital image chip. DMD is a digital image chip exclusively mastered and developed by Texas Instruments. Due to its relatively short launch time, DLP projection imaging optics that match DMD technology There are not many patented technologies of the system, and the existing LCD, LCOS and other projection lenses use a telecentric optical path system, which cannot fully meet the matching requirements of the DMD digital...

AI Technical Summary

Problems solved by technology

However, the application of aspheric lenses requires strict processing and assembly, which is not conducive to the improvement of production efficiency and the reduction of costs

In the technology that does not use aspherical lenses, in order to achieve better optical performance, the technical measures are: first, the number of lens combinations is large, generally more than 12 pieces; second, high-grade optical materials with high refractive index imported from abroad are used. , For example, materials such as FCD1, which have significantly improved aberrations, are expensive, poor in manufacturability, low in processing efficiency and yield

In a zoom projection lens disclosed in Japanese Patent No. 02120574, the materials used include FCD1, LAF and other high-grade materials, and the number of lenses is more than 12, so there are also problems such as high cost and low work efficiency.

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