The Improved Design Of Circuit Based On SZY-1Type Measurement Instrument Birefraction

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.