A Single Fiber Heterodyne Optical Fiber Hydrophone

Optical mixing errors in a fiber-optic coupled heterodyne interferometer

A lightweight and electrically passive interferometer is demanded by a number of applications for precision metrology such as machine tool metrology and on-machine feedback [1]. To satisfy these requirements, a fiber-optic coupled heterodyne displacement measuring Michelson interferometer (FIDMI) shown in Fig.1 has been developed in the Center of Precision Metrology (CPM) at the University of N...

Rotation detection by optical heterodyne fiber gyro with frequency output.

A fiber gyro with optical heterodyne detection is proposed. The experimental setup has been constructed and tested. Both the frequency difference in the fiber and the path-length difference between counterpropagating waves are eliminated to reduce output drift. An electronic circuit for phase-nulling detection has been constructed, which gives an electronic frequency output in proportion to the...

Dual polarization fiber grating laser hydrophone.

A novel fiber optic hydrophone based on the integration of a dual polarization fiber grating laser and an elastic diaphragm is proposed and experimentally demonstrated. The diaphragm transforms the acoustic pressure into transversal force acting on the laser cavity which changes the fiber birefringence and therefore the beat frequency between the two polarization lines. The proposed hydrophone ...

Heterodyne Ladar System Efficiency Enhancement Using Single-mode Optical Fiber Mixers

In-plane ultrasonic needle tracking using a fiber-optic hydrophone.

PURPOSE Accurate and efficient guidance of needles to procedural targets is critically important during percutaneous interventional procedures. Ultrasound imaging is widely used for real-time image guidance in a variety of clinical contexts, but with this modality, uncertainties about the location of the needle tip within the image plane lead to significant complications. Whilst several methods...