Font Size: a A A

The Theoretical And Experimental Research On Fiber-Optic Microphone

Posted on:2006-04-18Degree:DoctorType:Dissertation
Country:ChinaCandidate:Y L JiangFull Text:PDF
GTID:1118360212482871Subject:Physical Electronics
Abstract/Summary:PDF Full Text Request
Fiber-optic acoustic sensors have received more and more attentions because of its excellences such as high sensitivity and anti-EMI. A novel reflective fiber-optic microphone is introduced in this paper. The fiber-optic microphone is investigated theoretically and experimentally. A designed fiber-optic microphone system is realized and tested.In Chapter 1, fiber-optic acoustic sensors and its development are briefly reviewed.As the theoretical base of fiber-optic acoustic sensors, two models of reflective intensity-modulated fiber-optic microphone are studied in Chapter 2. Their modulation characteristics and choice of parameters are analyzed theoretically. Optical intensity modulation function of the fiber-optic microphone is given by using imaging principle. According to the oscillation theory of membrane, the inherence frequency and basic frequency of the flexible membrane are obtained.In Chapter 3, design of fiber-optic microphone is introduced in detail, and it is composed of probe, optical fiber, transmitter and receiver. The using of Y type fiber-optic coupler greatly simplifys the configuration of the sensor's probe. In order to reduce the system noise and enhance the signal-to-noise ratio, two types of circuit configuration have been designed.In Chapter 4, a fiber-optic microphone is tested. Test results show that basic functions of the microphone have been realized. High sensitivity and good frequency response have been achieved.In the last chapter, conclusions are given.
Keywords/Search Tags:Fiber-optic microphone, Reflective intensity modulation, Transmitter, Receiver, Fiber-optic coupler
PDF Full Text Request
Related items