LCOS接口专用集成电路的设计

根据LCOS显示以及各种输入视频信号的特点,总结了LCOS接口电路的功能特点.以场序彩色显示LCOS接口控制电路的设计实现为例,详细介绍了接口专用集成电路的设计方法.     

单片式彩色LCOS微显芯片电路设计

介绍一种单片式彩色LCOS微显芯片的电路设计。这种LCOS芯片配置合适的光机及电路系统可用于单片式LCOS彩色背投电视或其它投影产品。与传统场序彩色LCOS微显芯片类似，该芯片的主要模块由行扫描驱动器、数据驱动器和象素驱动矩阵三大部分组成。不同的是二者的行寻址方式不同，传统场序彩色LCOS采用的是逐行扫描法，而此处介绍的彩色LCOS采用的是随机寻址方式，将红、绿、蓝三种数据几乎同时写入象素矩阵，配合滚动的光照显示彩色图像。单片式LCOS系统与三片式LCOS系统相比可以节省微显芯片及配套电路系统数目，从而大大节约成本，在背投电视和其他投影产品产业中有很大的实用价值。     

Optimization of contrast for MTN45 LCOS panel

Abstract— MTN45 LCOS was studied experimentally and by simulation. Optimized retardance and orientation of the compensation retarder were found by simulation and verified by experimental data for both wire‐grid PBS and McNeil‐type PBS systems. The parasitic reflectance from the counter‐electrode (CE) glass and the retarder surface are two major effects that decrease the contrast of LCOS panels. Their effect was simulated by inserting several imaginary optical layers into the real system. Results also show that decreasing the retardance of the retarder; thus increasing the maximum driving voltage for the dark state can increase contrast. By combining all the improvements, we can achieve a contrast of 1500:1 in green and a contrast of 1000:1 in blue for MTN45 LCOS panels.     

Compensation of birefringence in lead‐free polarizing beam splitters for LCOS projectors

Abstract— Most optical designs for delivering light to LCOS imagers and then from the imagers to the projection lens use polarizing‐beam‐splitter (PBS) technology. Most of the PBSs used in commercial LCOS projectors contain glass with a significant amount of lead (Pb). Such glasses have inherently low stress birefringence, and therefore maintain the polarization state of light passing through them. However, Pb‐bearing glass is an expensive, difficult to process, and hazardous material with special disposal requirements and is therefore not desirable in consumer‐electronic products. On the other hand, Pb‐free wire‐grid plate PBSs require a longer back focal length than would be optimal. Data and modeling results show that uniform high‐contrast dark states may be obtained from lead‐free‐glass Cartesian PBS prisms when a quarter‐wave compensator is used between the imager and the PBS.     

Contrast behavior of a field lens with a wire‐grid PBS

Abstract— In an LCOS projection system, a wire‐grid PBS may be used to improve contrast and a field lens may be employed to simplify the projection lens. However, the combination of the two leads to a reduced contrast, which decreases with increasing field angle in one direction. In a representative arrangement, measured contrast with a mirror varied from over 10,000 in the center to 450 at the left and right edges. Contrast loss can be improved with a weaker field lens. The problem arises due to a phase delay between polarization states introduced by the wire grid. Polarization measurements show a +53‐nm phase delay with an axis parallel to the wire‐grid surface normal. Various compensation schemes are proposed in order to reduce the aforementioned loss of contrast.     

CRT替代技术在军用飞机平视显示器中的应用

随着数字显示技术的发展,目前平视显示器中普遍使用的CRT有被取代的趋势.国外早巳开始对,CRT替代技术的探索和研究,并已研制出新型HUD样机.可用于替代CRT产生图像的设备有:数字微镜装置、反射型液晶显示器和透射型液晶显示器等;可选用的光源有激光器、弧光灯、LED和荧光粉.对最有可能用于平显的几种显示技术和光源进行了综合比较,介绍了国外三家公司分别采用LCOS和DMD技术研制的新型平显情况,提出进行平显改进的必要性和思路.     

Green laser sources optimized for highly efficient microdisplay‐based field‐sequential mobile projectors

Abstract— A novel green laser source, based on a monolithic cavity microchip laser platform, has been developed. The laser is designed to be a part of a miniature and efficient RGB light source for microdisplay‐based mobile projector devices. The use of highly efficient, periodically poled MgO‐doped lithium niobate as the non‐linear frequency doubler allows for a significant increase in the overall efficiency of the green microchip laser. Specifically, a 50–150‐mW green output with a wall‐plug efficiency exceeding 10% in the temperature range of greater than 40°C has been demonstrated. A compact package for this laser source with a volume less than 0.33 cm³ is discussed and results of performance tests are presented.     

基于LPC3250的微型投影系统设计与实现

本系统以高性能ARM9处理器LPC3250为核心,HX88xx为LCOS驱动芯片。HX70xx为LCOS模块,LQ035Q1DG01为LCD模块,建立μC／OS-Ⅱ嵌入式实时操作系统,通过红外控制实现系统在投影仪和LCD之间切换。本文重点阐述了系统主要接口硬件电路的设计和系统软件的实现。实现了寿命长、成本低、可靠性高的便携式微型投影系统的设计。     

投影机用UHP灯性能及寿命延长措施

超高压汞灯(UHP)是液晶投影仪和液晶背投电视的光源,具有光效高、寿命长、光谱好和接近理想的点光源等特点,在DLP,LCD,LCOS等各种液晶投影显示系统中应用广泛。从安全使用的角度介绍了UHP灯芯和灯碗结构特点和设计要求,对UHP灯光谱特征以及延长UHP灯使用寿命的关键措施进行了讨论,并强调了合理的电气工作条件的重要性。     

硅基液晶（LCOS）与电光特性

文章以向列相液晶的弹性理论和Jones矩阵方法为研究基础,给出了90°MTN模式的电压-反射率实验曲线,概述了硅基液晶（LCOS）所使用的反射式显示模式的电压开态特性。对红、绿、蓝三色光,给出了90°MTN和SCTN两种模式的电压-反射率特性曲线,强调了电压开态下的色散效应。对于5V的暗态工作电压,给出了TN-ECB-1和45°MTN两种模式对比度随盒厚的变化曲线。