High‐pixel‐rate grating‐light‐valve laser projector

Abstract— A high‐pixel‐rate, high‐contrast (30,000:1) wide‐color‐gamut grating‐light‐valve laser projector is reported. A new optical engine enabling high‐frame‐rate (240 Hz) scan projection is employed. Panoramic wide‐angle‐scan projection with a 64:9 aspect ratio was also developed. Speckle noise is eliminated using a simple but highly efficient technique. The optical throughput efficiency of the grating‐light‐valve laser projector is reviewed.     

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VRML的幻灯机虚拟实验的设计与实现

VRML语言是一种建模语言,广泛应用于虚拟实验中。本文介绍如何利用VRML语言实现幻灯机的虚拟实验。     

基于斜投影算子的压缩域滤波法

通过对压缩感知和压缩域信号处理技术的研究,提出了一种基于斜投影算子的压缩域滤波法,在不精确已知目标信号稀疏位置的情况下,利用测量矩阵信息,构造斜投影滤波算子来完成干扰信号的滤除功能,从而达到直接利用压缩测量值不经信号重构而进行滤波的目的.理论分析了该方法的有效性.实验仿真结果表明,该方法能在压缩域有效地滤除非目标信号,并且相比于正交投影算子滤波法具有更好的性能.     

基于LED的均匀照明投影光路设计

在方棒照明系统的基础上,根据LED的发光特性和独特的准直结构,设计了一款基于LED的均匀照明投影光路系统．其优点是结构简单、开发周期短、加工成本低．仿真结果表明,其均匀度能满足中等要求．     

多媒体教室投影仪的科学维护

针对目前国内各高等院校为了大力发展现代化教育,建设了大量的多媒体教室,其中多媒体教室中的投影仪这一重要的教学设备,在教学过程中经常会突然出现故障,这些都严重影响到了正常的教学工作,为了提高投影仪的正常工作时间,降低投影仪的故障率,科学维护投影仪的工作至关重要,根据投影仪的工作原理,强调了对多媒体教室投影仪进行科学维护的重要性以及方法。     

Non‐planar projection performance evaluation and projector pose optimization

In projector applications, the actual display effect is primarily dependent on two aspects: projector performance parameters (intrinsic properties), and projector placement (extrinsic properties). Many studies have been conducted on the impact of the original resolution, illumination, and contrast ratio on projection performance. However, few studies have focused on the influence of extrinsic properties, including the position and orientation of the projector on the projection effect. In this paper, three projection performance evaluation criteria—projection resolution, resolution difference, and projection distance difference—are proposed in terms of extrinsic properties. Based on these evaluation criteria, a projection performance evaluation function was constructed. Through this function, as well as optimization employing the multi‐start and Monte Carlo methods, projector pose parameters corresponding to optimal projection effects can be obtained. Evaluations demonstrated that the proposed projection performance evaluation criteria could correctly describe the impacts of projector placement on projection effects. Projection systems arranged according to the projector pose optimization methods achieved good performance on screens in difference shapes with different numbers of projectors, where the resolution and display improved with no change of projector hardware parameters. The optimal projector poses calculated using these optimization methods can provide theoretical guidance for practical projector placement.     

液晶投影电视中视频信号与显示模件接口电路的设计与研究

本文介绍了液晶投影电视的基本原理和光学系统,根据液晶显示模件的接口参数,设计了液晶投影电视的接口电路,对该电路的工作原理进行了分析和讨论。同时,对行同步相位调整电路进行了详细的电路设计和研究。     

液晶投影仪上面板注射模设计

分析了液晶投影仪上面板结构和成型工艺,介绍了注射模结构、工作过程和关键机构,还介绍了针阀式热流道在模具中的应用。经过生产验证,模具结构合理、可靠,对类似制品的注射模设计具有一定的参考价值。     

液晶投影电视中视频信号与显示模件接口电路的设计与研究

本文介绍了液晶投影电视的基本原理和光学系统,根据液晶显示模件的接口参数,设计了液晶投影电视的接口电路,对该电路的工作原理进行了分析和讨论。同时,对行同步相位调整电路进行了详细的电路设计和研究。