Fig. 3
From: Ultrasonic signal detection based on Fabry–Perot cavity sensor
Schematic diagram of the F–P mode system. The 1550 nm fiber laser is connected with toroidal port 1 through a flange device. Interface port 3 is connected with the optical fiber. The optical intensity change returned by the detection light through the F–P cavity interference of the optical fiber is received by the photoelectric detector, and the test results are obtained after amplification and acquisition processing. PD: Photoelectric detector; DAQ: Data collection card; PC: Personal computer