Radiant energy – Photocells; circuits and apparatus – Optical or pre-photocell system
Patent
1987-06-10
1988-08-09
Nelms, David C.
Radiant energy
Photocells; circuits and apparatus
Optical or pre-photocell system
250214R, H01J 516
Patent
active
047629924
ABSTRACT:
An error detection system is provided for a two-state fiber optic sensor. An amplified photodetector signal is sampled by each of an ON-OFF threshold detector, a disconnect threshold detector and a slope detector. The ON-OFF threshold detector monitors whether the detector signal is above or below an ON-OFF threshold value corresponding to the parameter being sensed and activates an appropriate sensor output. The disconnect threshold detector monitors the constant low level detector signal corresponding to low level light received by the detector even when the thresold detector is in the OFF state, and triggers an error signal should the detector signal fall below a disconnect threshold value. The slope detector monitors the rate of change of the detector signal. Where the detector signal changes rapidly, such as during normal sensor switching, the slope detector permits the detector signal to pass to a latch, which retains in memory the last detector signal which changed rapidly enough to trigger the slope detector and produces an output corresponding to the ON-OFF status of the last detector signal in memory. A slowly changing detector will not trigger the slope detector. Where the outputs of the ON-OFF threshold detector and the latch differ, a comparator triggers an error signal.
REFERENCES:
patent: 4449043 (1984-05-01), Husbands
patent: 4574192 (1986-03-01), Kitagawa et al.
Gat Erann
Mathis Talmage
Park Eric D.
Kollmorgen Corporation
Nelms David C.
LandOfFree
Error detection system for two-state fiber optic sensors does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Error detection system for two-state fiber optic sensors, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Error detection system for two-state fiber optic sensors will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-919836