国内外彩色STN-LCD的应用及发展动态

本文介绍了彩色STN-LCD的性能、特点及与其他显示器件的比较，阐述了彩色STN-LCD的应用、国内外发展的动态以及未来的变化的趋势。文中也对国内发展彩色STN-LCD所面临的问题进行了讨论。     

STN-LCD技术的发展

介绍了目前人们对改善STN－LCD特性所取得的一些研究进展，主要包括反射式STN－LCD彩色显示，高分辨率STN－LCD用液晶材料，采色STN－LCD用彩色滤光膜，以及STN－LCD用光学膜，如偏振片、相位差补偿膜等。     

用微锥膜改善反射式彩色液晶显示器件的视角

本文提出并设计了一种具有微圆锥形结构的膜，用于改善反射式彩色液晶显示器的色度和视角。模拟计算结果表明，这种膜可以准直从锥形底部入射的光，向前散射由锥形顶部入射的光。作为应用实例，我们分析了微圆锥形结构膜对反射式干涉彩色滤光膜视角特性的影响，其作用十分显著。由于微锥膜的作用不依赖于液晶器件层，所以对多种模式的反射式彩色液晶显示器都是有效的。     

利用微锥膜改善反射式液晶显示器件的视角

提出了一种可以改善反射式彩色液晶显示视角的微锥结构膜。模拟计算结果表明,当光从微锥的底部人射时,该膜起到准直作用,当光从微锥的顶部入射时,该膜起到散射作用。利用微锥膜可显著改善反射式干涉滤光膜的视角依赖性。由于微锥膜的作用不依赖了液晶盒结构,所以,可对多种结构的反射式彩色液晶显示有效。     

彩色滤光膜硅覆液晶微显示器中像素尺寸及滤光膜厚度对彩色侧向场效应的影响

应用彩色滤光膜硅覆液晶(Color Filter Liquid Crystal on Silicon,CF-LCoS)微显示器件的三维光学模型;研究了像素尺寸和彩色滤光膜厚度对彩色侧向场的影响。这两个参数可以影响微显示器件的色纯度、光反射率以及对比度等性能参数。对于特定的应用,需要考虑器件所有的性能参数要求,才能对像素尺寸和彩色滤光膜厚度进行优化。     

Visible Light Communication with Color and Brightness Control of RGB LEDs

We propose a visible light communication system in which the color and brightness are controllable. Pulse width modulation and variable pulse position modulation (VPPM) schemes are used to control the color and brightness, respectively. A digital algorithm to decode VPPM signals is suggested and implemented. A seamless transmission is observed in a testbed experiment under various environmental conditions. The proposed scheme can be applied to emotional‐lighting‐based wireless optical communication.     

Color Imaging System Using a Single CCD Area Array

A color imaging system employing a single CCD sensor with a color filter array has been implemented. The system incorporates color channel enhancement and interpolation and provides display on a conventional color video monitor. Color correction matrix coefficients are computed. The response of the system is compared to that of a photographic film.     

液晶光阈中的高反射介质镜的研究

讨论了液晶光阀中的高反射介质镜的介质膜最大的层数,由3个不同中心波长的1／4波堆叠加形成的介质镜结构和各膜层的厚度,导出了这种叠加结构介质镜的反射率公式,。计算和测量了反射率随入射光波长,入射角,介质膜导 及其折射率的变化。     

基于FSS 覆层的高增益稀疏阵列天线设计*

设计了一种基于FSS 覆层的高增益EBG 谐振天线。设计了一种在预定频段内谐振的FSS 单元,作为覆层加载到微带贴片天线上方。仿真结果显示,在5GHz 频点,加载覆层的天线增益为11.43dB。接着,还研究了FSS 覆层在稀疏阵列中的应用,在这个结构中,采用一个2×2 的阵元间距较大的天线阵作为馈源。对该结构进行加工和测试,结果显示天线阵增益为18. 54dB。同时,阵列在E 面和H 面的副瓣分别为-9.17dB 和-12.04dB,避免了栅瓣的产生。     

Radiolocation System Using Distributed Sensor Array Onboard a High Altitude Aerial Vehicle

High altitude aerial vehicle, or platform, is expected to help public safety by monitoring various kinds of radio transmission with a high resolution, such as search and rescue signals and emergency calls, in addition to the optical monitoring and wireless relay. Unmanned aircrafts or airships are the candidates for the platform vehicle with those purposes. This paper proposes a system that estimates the location of transmitter sources on the ground by a large-aperture sensor array mounted on the high altitude aerial vehicle with a flexible structure and discusses on a real time calibration method for the position and internal phase errors of sensor elements.     

基于SRAM光栅光调制器阵列控制系统电路的研究

提出一种基于静态随机存储器(SRAM)的光栅光调制器阵列控制系统电路.介绍了光栅光调制器的加工工艺和工作原理,分析了该控制系统电路的原理和技术指标.利用Cadence软件和无锡华润上华0.5μm工艺,设计和加工了大小为8×8的控制系统电路.通过实验表明:加工的SRAM有源矩阵单元能够实现对输出电压的更新或保持;且加工的控制系统电路能够实现对光栅光调制器阵列的有源控制,从逻辑功能上验证了该控制系统电路设计的正确性.结果表明:只要该控制系统电路的行、列驱动电路能够在248MHz的时钟频率下工作,且有源矩阵单元的开关时间小于121ns,则该控制系统电路可以满足分辨率为1920×1080,帧频为30Hz,灰度级为256的投影显示.     

新型多功能交通灯控制系统的设计

介绍了一种新型多功能交通灯控制系统，重点介绍了应用新型在系统可编程器件（ISP）来实现多功能交通灯控制系统的设计方法。     

Biomimetic Polymer Film with Brilliant Brightness Using a One‐Step Water Vapor–Induced Phase Separation Method

The scales of the white Cyphochilus beetles are endowed with unusual whiteness arising from the exceptional scattering efficiency of their disordered ultrastructure optimized through millions of years of evolution. Here, a simple, one‐step method based on water vapor–induced phase separation is developed to prepare thin polystyrene films with similar microstructure and comparable optical performance. A typical biomimetic 3.5 µm PS film exhibits a diffuse reflectance of 61% at 500 nm wavelength, which translates into a transport mean free path below 1 µm. A complete optical characterization through Monte Carlo simulations reveals how such a scattering performance arises from the scattering coefficient and scattering anisotropy, whose interplay provides insight into the morphological properties of the material. The potential of bright‐white coatings as smart sensors or wearable devices is highlighted using a treated 3.5 µm film as a real‐time sensor for human exhalation.     

滞环电流控制的大功率LED恒流驱动芯片设计

设计了一款滞环电流控制的大功率LED恒流驱动芯片,其采用高边电流检测方案,通过内部电流检测电路对LED驱动电流进行滞环控制,从而获得恒定的平均电流。芯片采用9VBICMOS工艺流片,可输出350mA电流驱动1W的LED,也可输出750mA电流驱动3W的LED。在4.5～9V输入电压范围内,芯片输出驱动电流变化小于3.5%。在环境温度从25°C变化到100°C时,芯片输出驱动电流变化小于5%。由于滞环电流控制环路存在自稳定性,芯片无需补偿电路。     

Power-Stabilization of High Frequency Gyrotrons Using a Double PID Feedback Control for Applications to High Power THz Spectroscopy

High stabilization of the output power of high frequency gyrotrons for high power THz spectroscopy is an important issue in order to extend the applications of gyrotrons to wider subjects. For this objective, we tried a PID feedback control on a heater current of a triode magnetron injection gun (MIG) for stabilization of an electron beam current and an additional PID control of an anode voltage of the gun for direct stabilization of output power. This double PID control achieved effective responses for the stabilization of output power in both slow (from several tens seconds to several minutes) and fast (from milliseconds to seconds) time scales.