【作者】 刘红；

【导师】 刘锦高； 王蔚生；

【作者基本信息】 华东师范大学 ， 通信与信息系统， 2012， 博士

【摘要】 近年来,随着数字电视和互联网络等的普遍应用,显示领域的技术和应用市场进入了快速变化和飞速发展时期。而在众多不断发展的显示技术中,激光显示技术是显示技术未来发展的趋势和主流方向,也是未来显示领域竞争的焦点。基于激光器具有的独特特点：高功率和散射角度小,激光投影设备可以满足高端商务应用和家庭消费对显示高画质的要求,并在技术上克服了传统光源投影技术的先天不足,有望逐步占领投影机商务应用和家用大屏幕市场的份额。而基于激光显示技术的新一代激光家庭影院可以发展成为大屏幕电视的高端产品,其产品附加值高,是激光显示技术的重要发展方向之一。除此之外,激光显示技术还将进入公共信息大屏幕、天文观测和水幕成像表演等民用市场,其市场前景广阔。本文对激光投影中所涉及的主要问题：大功率激光光源的光束整形以及耦合输出、激光光源的散热及白平衡矫正、激光显示中消散斑问题等主要技术难点进行了研究。最后在软件仿真优化的基础上,给出了三片式LCOS激光光学引擎的设计方案,并对二次样机的性能进行了测试。论文的主要研究成果如下：(1)介绍了LCOS工艺,以及其显示原理。重点对三片式LCOS激光投影显示系统进行了研究,并对项目中所用的LCOS芯片进行了性能测试和设计了系统的白平衡模块。(2)在高功率倍频过程中,根据热传导方程对高功率激光利用PPLN晶体倍频进行了热效应分析,为实现高功率倍频激光奠定了理论基础。提出新的耦合方案,通过单光纤对多个激光单元进行耦合,实现了激光的大功率耦合输出,并分别对蓝光和绿光的耦合效率进行了计算。(3)研究了大功率激光光源散热问题。首先此大功率激光模组阵列采用串联／串并联结合的优选排列方式,讨论了几种常见的激光模组散热方式的可行性,确定了项目中激光模组的散热方案,通过加入控制器,进行风冷和铜导热冷却的方式。(4)激光显示消散斑问题是激光显示的重要研究课题,本文通过建立激光散斑模型,模拟激光高斯散斑场。经过CCD相机和计算机图像处理系统,对激光散斑的图样进行分析和量化,形成了激光投影显示图像消散斑测量的完整方案。在综述国内外已有的消散斑方法基础上,提出了新的三种消散斑方案。(5)利用软件优化设计了一款利用RGB三基色激光作为光源的三片式LCOS激光投影光学引擎。对光学引擎中用LSR装置消散斑进行讨论,并用软件solidwork机械设计了LSR模块。加工制作的首台样机,发现其不足,进行改进,优化设计了第二台样机。(6)结合显示系统测量方法,对二次样机性能进行了测试。LSR模块散射片设计和制作了5°、10°和20°。实验验证用10。的散射片旋转的方法能有效减弱我们研究的系统中对激光散斑的影响,使得大功率的投影系统的散斑对比度降到4.2%<5%。达到了人眼可以接受的范围。经过实验室检测和专业部门送检,验证了我们设计的二次样机光学性能指标高,主要技术指标均达到项目目标的要求。通过以上工作,解决了863项目“1000流明级激光高清投影机产业化关键技术”中的主要问题。通过样机的成功制作和检测性能达标,有望带动相关产业化的生产以及配套的发展,形成激光投影产业链。本文的研究对大功率的激光投影机研究和应用推广有重要的参考价值。更多还原

【Abstract】 In recent years, due to the huge demand of the digital TV and broadband network applications etc., the display technology and market is in sharp change and rapid development period. In many of the continuous development of the display technology, the laser display is representing the future development trend and main direction of the display technology, which is the focus of competition. Based on the laser has unique characteristic:high power and low astigmatism. The laser projection can meet the business application and requirements of household for its high display quality, which overcomes the lamp light source’s shortcoming. It will replace market share of the original business applications. So, the laser display is a new generation of laser home theater and will become a high-end product of the big screen TV’s. Its products have high additional values, and laser projection is one of the important development directions of the display technology. In addition, laser display technology will also be used to public information screen, astronomical observation, water curtain imaging performance and other application of civilian market, etc. which has broad market.This article does a lot of research works on the laser projection, such as the high power laser output, laser radiation, beam shaping, laser cooling, and white balance correction and reducing laser speckles. Finally based on software simulation optimization, we presented the design scheme of the three LCOS laser optical engine, and test the performance of the second prototype.In this paper, the major research results are as follows:Firstly, we introduce the LCOS technology, and its display principle. We tested the performance of the LCOS chip, which will be used in the projection. And we designed the white balance module of the system.Secondly, in the process of frequency doubling, and according to the temperature distribution of PPLN, we have calculated thermal effect in the process of frequency doubling. This work laid a theoretical foundation on laser frequency doubling. We put forward the new coupling scheme.Through a single fiber laser to multiple laser unit, we realize the high power output. And we calculated the coupling efficiency of blue laser and green laser. Thirdly, we discussed the cooling problems of the high power laser. Firstly, we must know the laser module array. And the cooling scheme of light source and discussed several common cooling forms of laser module. We determined the laser cooling method by joining the controller, driving the fan and copper heat conduction.Fourthly, in order to solve the problem of laser speckles, which is an important research topic in the laser display, we have established the laser speckle model, and also simulated the laser speckle by Gaussian rand on surface.This paper gives a certain laser speckle measurement standard through the CCD camera and image processing system by analyzing and quantifying the laser speckle pattern. The measurement standard is the only standard on speckle measurement of laser display. This project summarized reducing speckle methods at home and abroad, and three new schemes of suppressing the speckle noise in images display are proposed.Fifthly, using RGB lasers as the light sources, we designed optical engine of the three LCOS-laser projector. And we designed the LSR module by software solidwork. We processed the first projector and found its shortage. So we optimized and designed the second projector.Sixthly, combined with measurement method of display system, the second prototype was tested. The paper designed and manufactured the diffusers with different diffraction angles, such as5°、10°nd20°. The experiments indicate the diffuser with10°can best performance of reducing the laser speckles. The speckle contrast of the high-power projection system is reduced to4.2%, which is less than5%and achieve the human acceptable range. After test and professional inspection department verified the second prototype, which performance index is high, and the main indexes all reached the requirements of the projector.In conclusion, the above research results in this paper solve key technology problems of the1000lumen level laser projector, which lay the foundation to realize the industrialization of laser projection display. And through the project application, it will drive the fast development of relevant industries. It has important reference value for the research and application promotion of high power laser projector.更多还原