Photoelectric detector amplitude-frequency response calibration method

Abstract

The invention discloses a photoelectric detector amplitude-frequency response calibration method. A heterodyne ineterferometer is composed of a polarization beam splitter, reflectors and acoustic optical modulators; a beat frequency signal generated by the heterodyne ineterferometer serves as an excitation signal for calibrating frequency response of a photoelectric detector; and frequency shifting range, number and cascade method of the acoustic optical modulators in the heterodyne ineterferometer are configured to adjust frequency range and frequency resolution for photoelectric detector frequency response calibration. By utilizing the photoelectric detector amplitude-frequency response calibration method, the problems that the application of a light source internal modulation method is susceptible to external temperature fluctuation and the frequency resolution is low are avoided, the calibration frequency range and frequency resolution can be flexibly adjusted according to application requirements, the system is simpler, and the limitations of environment vibration and mechanical device resonance to the calibration frequency range in a photo-mechanical rotation method are avoided.

Description

technical field [0001] The invention relates to the technical field of light measurement, in particular to a method for calibrating the amplitude-frequency response of a photodetector. Background technique [0002] Photodetectors are key devices in optical communication and optical measurement systems, and their measurement bandwidth determines the communication rate and measurement accuracy of the system. Therefore, the measurement of the frequency response characteristics of photodetectors is one of the key technologies in the field of optical communication and optical measurement. In the field of optical measurement, especially in metering applications, the purpose of measuring the frequency response characteristics of photodetectors is to correct the measurement errors caused by their frequency distortion, which requires higher accuracy and frequency resolution of frequency response measurements. [0003] In ultrasonic / hydroacoustic measurement, the hydrophone is the ba...

AI Technical Summary

Problems solved by technology

In the laser interferometry, the photodetector generally uses an avalanche photodetector with a bandwidth of about 100 MHz and high gain, and its frequency distortion is the main source of uncertainty in hydrophone calibration. High-precision calibration is the key technology to reduce the uncertainty of hydrophone calibration. However, the existing technical solutions cannot satisfy the calibration frequency range and frequency resolution at the same time. The general modulation method in the light source is easily affected by external temperature fluctuations and the frequency resolution is low.

Images