【作者】 董旭；

【导师】 赵建平；

【作者基本信息】 曲阜师范大学 ， 通信与信息系统， 2012， 硕士

【摘要】 双折射率是表征各向异性晶体光学特性的一个重要的光学参数，它决定于材料的成分结构以及生成条件等多种因素，并且与波长有关[1]。测量双折射率的方法多样，电光调制法就是其中一种。SZY-1型双折射测试仪是基于电光调制的原理测量双折射率的一台仪器。本文在研究了SZY-1型双折射测试仪使用说明书及电原理图的基础上，结合当前最新的电子技术、单片机技术、光通信技术、计算机技术，改进和开发了高集成、高可靠的双折射测试仪系统。针对国内电子电路发展的现状和嵌入式单片机的发展趋势，本文对SZY-1型双折射测试仪的三个骨干模块：电光调制信号源、高压电路、信号接收及处理电路进行了重新设计。其中电光调制信号源的设计应用了单片机编程产生信号并控制相移的方法，其设计原理简单，易于控制。高压电路模块应用了开关电源对其加以设计，产生的高压和信号源一块加载在电光调制器上对光信号进行控制。电光调制器输出的光信号经信号接收和处理模块后显示在示波器上。系统对电光调制信号源、高压电路和信号接收及处理电路的硬件设计及软件设计做了详细的介绍。电光调制信号源的硬件电路以单片机STC89C52作为核心处理器，采用模块化设计，在保证可行性的基础上，提高了电路的集成度。高压电路模块选用了UC3842做为开关电源的核心芯片，实现了系统的集成化设计。信号接收和处理模块对窄带选频放大器进行了分析和改进并对所需的示波器进行了选型。系统对各部分的电路进行了仿真，对出现的结果进行了讨论，还对改进后测量系统的测量方法进行了叙述。根据电光调制法的原理，在调节相应波形变化的基础上，用选定的电压表测出高压电路的输出电压，即可根据推出的公式计算出待测样品的双折射率。经过多次软硬件调试和现场调试，本系统实现了SZY-1型双折射测试仪的所有功能。更多还原

【Abstract】 Birefringence is a very important optical parameters characterizing the optical properties ofanisotropic crystals, determined by the composition of the material structure and formationconditions and other factors, and It is related to the wavelength. There are variety of methods formeasuring birefringence, one of which is electro-optical modulation method. SZY-1typemeasurement instrument birefraction is an instrument that measures the birefringence based onthe principle of electro-optic modulator. This paper studys the manual and the electricalschematic of SZY-1type measurement instrument birefraction,combines the latest electronictechnology, microcomputer technology, optical communication technology, computer technology,improves and develops a highly integrated, highly reliable measurement instrument birefraction.According to the development situation of the domestic electronic circuits and the developtrend of embedded microcontroller,This paper redesigns measurement instrument birefraction’sthree key modules which include the electro-optical modulation signal source, high voltagecircuit, the signal receiving and processing circuit. The design of electro-optic modulation of thesignal source is applied microcontroller programming to generate the signal and control thephase shift method. the design principle is simple and easy to control. The high voltage circuitmodule is designed with switching power supply. High-voltage and signal source is loaded onthe electro-optic modulator to control light signal. The optical signal that electro-optic modulatoroutputs passes the signal receiving and processing module and is displayed on an oscilloscope.The system described in detail the hardware design and software design of theelectro-optical modulation signal source, high voltage circuit and signal receiving and processingcircuit. The core processor of Electro-optical modulation signal source’s hardware circuit isMCU STC89C52. It adopts modular design and raises the level of integration of the circuit onthe basis of feasibility.The high voltage circuit module selected UC3842as switching powersupply’s core chip to achieve the integrated design of the system. Signal reception andprocessing module analysis and improves of the narrow-band selective frequency amplifier andchooses the cilloscope’ model.The system simulates the various parts of the circuit, discussed the results and describes theimproved measuring system. According to the principle of electro-optical modulationmethod,basing on adjusting the corresponding waveform change, It selects voltmeter to measurethe output voltage of high voltage circuit then we can launch formula to calculate thebirefringence of the sample.After a number of hardware and software debugging and on-site debugging The system realizes t all the features of SZY-1type measurement instrument birefraction.更多还原