Method for determining frequency or phase difference between polarized ray of light and polarizing local oscillator ray of light, involves receiving of ray of light from transmission device, and decoupling local oscillator ray of light

摘要

The method involves receiving of a ray of light (12) from a transmission device (14), and decoupling local oscillator ray of light (18) from a local oscillator (16). Two interference beams (28,32) are produced, which has a beat dependent of one the frequency difference from the ray of light and the local oscillator ray of light in overlaying and polarization-separating parting. Two electrical beat signals are produced from the two interference beams to determine the frequency difference. An independent claim is also included for a device for collecting frequency or phase difference between a polarized ray of light and a polarizing local oscillator ray of light.