半导体激光器自混合干涉的调制及光电检测电路

根据半导体激光器自混合干涉微位移测量系统的要求,设计了电流调制半导体激光器和光信号检测电路．半导体激光器具有体积小、易调制等特性,因此在实验采用中心波长为650 nm的半导体激光器作为该微位移测量系统的光源, 从而使系统微型化、光路易准直;将半导体激光器的电流调制特性和自混合干涉原理相结合,使此微位移测量系统的测量精度远远高于传统干涉方法．在实验电路中利用集成运放特性实现对光源信号的调制和微弱信号的前置放大,并使用温度补偿及抗干扰技术,使输出信号满足系统要求．

The Modulating and Photoelectric Detecting Circuit Design for Laser Diode Self-mixing Interference

According to the requirements of laser diode self-mixing interferometry' s system, the circuit of current modulating laser diode and detecting photosignal is designed. Because of micro capacity and easily modulation of laser diode, the laser diode with 650 nm-middle-wavelength is applied as the photosource of this system, which make for the system more miniature and the beam path more collimated. Combining the characteristics of laser diode current modulation with the theory of self-mixing interferometry leads to a much more precise measurement of system than that of the technique of conventional interferometry. The modulation of photosource and the preamplification of weak signal are actualized by the characteristics of integrated operational amplifier. In addition, by utilizing the technology of temperature compensation and anti-interference in experimental circuit, the system obtains expected result of the output signal.