Radiant energy – Photocells; circuits and apparatus – Optical or pre-photocell system
Patent
1988-04-25
1989-11-07
Nelms, David C.
Radiant energy
Photocells; circuits and apparatus
Optical or pre-photocell system
2502221, 340555, G01N 904
Patent
active
048794619
ABSTRACT:
An energy field disturbance sensor comprises an energy field emission means such as a light emitting diode; the emitted field may contain a time-varying component. An energy sensing device such as a photodiode receives the field energy to produce a sensing signal related to the intensity of the emitted field and any disturbance therein. A second signal complementary to the sensed signal is added in a summing junction to the sensing signal to create a summation signal. If the emitted energy field contains a time-varying component, a detection circuit is used to sample the summation signal to convert the summation signal to a proportional detection signal. An analog to digital converter converts the detection signal to a digital form. Digital processing circuitry modulates the amplitude of the complementary signal or the intensity of the energy field according to the desired mode of operation, and in accordance with the behavior of the digital detection signal and external control signals. The circuitry is capable of creating a null condition in the detection signal when the received amplitude of the energy field is such that when added to the complementary signal a cancellation effect occurs; the null condition may be transient or continuous in nature depending on the mode of operation and the nature of the field disturbance.
REFERENCES:
patent: 1806199 (1931-05-01), Hardy et al.
patent: 2227147 (1940-12-01), Lindsay
patent: 3278923 (1966-10-01), Archer
patent: 3278924 (1966-10-01), Archer
patent: 3281817 (1966-10-01), Archer
patent: 3428815 (1969-02-01), Thompson
patent: 3597755 (1971-08-01), Parkin
patent: 3644917 (1972-02-01), Perlman
patent: 3858043 (1974-12-01), Sick et al.
patent: 3859043 (1975-01-01), Corbin
patent: 3867628 (1975-02-01), Brown
patent: 4032777 (1977-06-01), McCaleb
patent: 4310756 (1982-01-01), Sick et al.
patent: 4467251 (1984-08-01), Jonsson
patent: 4581526 (1986-04-01), Brattgard
patent: 4736097 (1988-04-01), Philipp
Philipp, Harald; "Optical Sensing Technique #1"; Document No. 183900, Dec. 21, 1987.
Bushong, D. B., "AGC-Controlled Light-Beam Detector Ignores Ambient Light Changes", Electronic Design, vol. 29, No. 19, pp. 188-190, (Sep. 17, 1981).
Pshaenich, A., "Constant-Current Feedback Loop Improves Photodetector Performance in Optical Sensors".
Opcon, Inc., Instruction Manual, "8215A Low-Contrast Module", Document No. 102554-7904 from Opcon, Inc., 720 80th St., S. W. Everett, WA 98203-6299.
Allen Stephone B.
Jackson Larry A.
Nelms David C.
LandOfFree
Energy field sensor using summing means does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Energy field sensor using summing means, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Energy field sensor using summing means will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-85235