弹光调制干涉具调制的干涉光被探测器接收后输出高速变化的微弱电信号，能否将该电信号提取并放大输出对弹光调制-傅里叶变换光谱仪的研制至关重要。通过对调制干涉光进行理论分析，设计一种具有高信噪比和较高带宽的光电转换放大电路，主要由电源电路、光电转换电路、放大电路、理论通频带为100 kHz~3.5 MHz的带通滤波电路组成。实验结果表明：设计的电路能够将探测器输出的最大频率为1.6 MHz的信号放大至670 mV左右，实现了将探测器输出的微弱速变电信号从背景噪声中有效提取与放大，为后续傅里叶变换提供可靠数据。

The output of detector which receives the interference light that is modulated by photoelastic modulated interferometer is weak electric signal that is of rapid change. Extracting and amplifying this electric signal is crucial to the development of the photoelastic modulator-Fourier transform spectrometer. A photoelectric conversion amplifying circuit with high signal-to-noise ratio and high bandwidth was designed through analyzing the interference light. The circuit consists of power circuit, photoelectric conversion circuit, amplifying circuit and the band-pass filter circuit with the theoretical pass band of 100 kHz ~ 3.5 MHz. The test results indicate that the circuit can amplify the signal from the detector whose maximum frequency is 1.6 MHz to about 670 mV, extract and amplify the output signal effectively from the background noise, and provides reliable data to the subsequent Fourier transform.