Radiant energy – Photocells; circuits and apparatus – Optical or pre-photocell system
Patent
1989-01-25
1990-01-30
Nelms, David C.
Radiant energy
Photocells; circuits and apparatus
Optical or pre-photocell system
356345, H01V 516
Patent
active
048975435
ABSTRACT:
An apparatus and method for minimizing polarization-induced signal fading in an interferometric fiber-optic sensor is disclosed. In a preferred embodiment of the invention, the polarization state of an input light beam is changed by a polarization controller as a function of first and second control signals applied to the controller. The input light beam with the changed polarization state is applied to the input of an interferometric fiber-optic sensor, causing the interferometric fiber-optic sensor to form an interference pattern at its output. This interference pattern is photodetected to develop an electrical signal that has a peak-to-peak amplitude proportional to the visibility of the interference pattern. A control circuit is responsive to the electrical signal for controllably developing the first and second control signals to change the polarization state of the input light beam to maximize the peak-to-peak amplitude of the electrical signal, thereby minimizing the polarization-induced signal fading in the interferometric fiber-optic sensor. The electrical signal is also demodulated to produce an output signal that is proportional to the field being sensed by the interferometric fiber-optic sensor.
REFERENCES:
patent: 4530603 (1985-07-01), Shaw et al.
patent: 4597640 (1986-07-01), Buhrer
patent: 4653915 (1987-03-01), Frigo et al.
patent: 4671113 (1987-06-01), Carome
patent: 4729622 (1988-03-01), Paviath
"Remote Polarization Control For Fiber-Optic Interferometers", by K. H. Wer et al., Optics Letters, vol. 12, No. 3, Mar. 1987, pp. 217-219.
"Dependence of Visibility on Input Polarization in Interferometric Fiber-Optic Sensors", by A. D. Kersey et al., Optics Letters, vol. 13, Apr. 1988, pp. 280-290.
"Optimization and Stabilization of Visibility in Interferometric Fiber-Optic Sensors Using Input-Polarization Control", by A. D. Kersey et al. Journal of Lightwave Technology, vol. 6, No. 10, Oct. 1988, pp. 1598-1609.
Jameson George
McDonnell Thomas E.
Nelms David C.
The United States of America as represented by the Secretary of
LandOfFree
Apparatus and method for minimizing polarization-induced signal does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus and method for minimizing polarization-induced signal , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method for minimizing polarization-induced signal will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1924820