Radiant energy – Photocells; circuits and apparatus – Photocell controlled circuit
Patent
1992-05-28
1993-04-27
Nelms, David C.
Radiant energy
Photocells; circuits and apparatus
Photocell controlled circuit
2502221, 340557, H01T 4014
Patent
active
052065006
ABSTRACT:
A photodetector receives an optical signal and converts it an electrical signal. A pulse stretcher converts the electrical signal into a first signal which is characterized by having an increased pulse width relative to the electrical signal. A noise averager converts the electrical signal into a second signal which is representative of the average noise component of the electrical signal. A threshold reference is generated as a linear function of the potential difference between the first signal and the second signal. A first comparator compares the magnitude of the first signal and the threshold reference signal and generates a first logic output which is true if the magnitude of the first signal is greater than the magnitude of the threshold reference signal. A second comparator compares the magnitude of electrical signal and the threshold reference signal and generates a second logic output which is true if the pulse width of the electrical signal measured as a funtion of time is greater than the response time of the second comparator. A logic circuit generates an alert indication if the first logic output is true and the second logic output is false.
REFERENCES:
patent: 4249160 (1981-02-01), Chilvers
patent: 4277170 (1981-07-01), Miles
patent: 4383238 (1983-05-01), Endo
patent: 4447800 (1984-05-01), Kasuya et al.
patent: 4477184 (1984-10-01), Endo
patent: 4527158 (1985-07-01), Runnels
patent: 4631542 (1986-12-01), Grimsley
patent: 4724312 (1988-02-01), Snaper
patent: 4755818 (1988-07-01), Conrad
patent: 4851661 (1989-07-01), Everett, Jr.
patent: 5001777 (1991-03-01), Liautaud
patent: 5008531 (1991-04-01), Ono et al.
patent: 5008532 (1991-04-01), Ono et al.
patent: 5010341 (1991-04-01), Huntley et al.
patent: 5066121 (1991-11-01), Bernhard
patent: 5083129 (1992-01-01), Valentine et al.
patent: 5087808 (1992-02-01), Reed
patent: 5142142 (1992-08-01), Senechalle et al.
Decker Lawrence G.
Hume Edward F.
Poston Janet R.
Cincinnati Microwave, Inc.
Messinger Michael
Nelms David C.
LandOfFree
Pulsed-laser detection with pulse stretcher and noise averaging does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Pulsed-laser detection with pulse stretcher and noise averaging, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Pulsed-laser detection with pulse stretcher and noise averaging will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2329401