Frequency locking device

Details Frequency locking device Frequency locking device

1988-04-13

1990-05-15

Rosenberger, Richard A.

Optics: measuring and testing

Refraction testing

331 9, G01N 2141, H03L 700

Patent

active

049253026

ABSTRACT:
An improved frequency locking circuit suitable for indirectly locking an optical frequency f.sub.0 to a radio frequency f.sub.1 or of locking the radio frequency to the optical frequency. A beam of optical frequency f.sub.0 is modulated by a compound signal which is the sum of a signal at frequency f.sub.2 and an FM subcarrier at frequency f.sub.1 that is phase modulated at frequency f.sub.3 to produce a phase modulated beam. The phase modulated beam is filtered by a filter having a transfer function having a characteristic frequency f.sub.f. A pair of control signals are generated that are proportional respectively to the amplitudes of two components of the filtered signal at frequencies f.sub.2, f.sub.3. These control signals are separately used in a pair of servo loops to separately establish fixed values of f.sub.0 /f.sub.f and f.sub.1 /f.sub.f. By using an optical cavity of the filter, the frequency locking circuit may be used for measuring the refractive index of a gas. The circuit may also be used for calibrating a multi-mode filter.

REFERENCES:
patent: 3552860 (1971-01-01), Granqvist
patent: 4631498 (1986-12-01), Cutler
patent: 4746878 (1988-05-01), Cutler

Affiliated with

Also associated with

Rating

Frequency locking device does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Frequency locking device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Frequency locking device will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-618299