半導体レーザを用いた音波検出に関する研究

Abstract

There are various sound wave detection methods. In this work, the sound wave detection using a semiconductor laser has been studied. In comparison with conventional microphone, this device can detect wide frequency and is trong in high sound pressure. The prototype device was able to detect a sound in frequency of 300Hz-40kHz. We can hear directly the human voice by joint the output of the device with a speaker. However, there is a variation of measured value ,and is a weakness for vibration. This can be improved by arranging the measurement environment. Furthermore, the output voltage of the device has a maximum at 10cm. In addition, the angle of the speaker is sensitive at the right angle on the laser beam.