Electrical pulse counters – pulse dividers – or shift registers: c – Applications – Counting animate or inanimate entities
Patent
1987-09-01
1989-01-17
Heyman, John S.
Electrical pulse counters, pulse dividers, or shift registers: c
Applications
Counting animate or inanimate entities
2503383, 250342, 340567, G08B 1318, G06M 700, G01J 508
Patent
active
047992433
ABSTRACT:
An arrangement for detecting the passage of living beings through a surveillance region into and out of a controlled-access space includes at least one pyroelectric detector device that includes two detector elements which have active areas that are directly exposed to thermal radiation from the surveillance region and convert the thermal radiation energy received thereby into electrical signals with opposite polaritites. The detector elements are situated in succession in the direction of passage into the controlled-access space. The surveillance region is optically subdivided into two surveillance zones arranged in succession as considered in the passage direction, for instance by a mask that masks an intervening zone situated between the surveillance zones to prevent thermal radiation from the intervening zone from reaching either one of the detector elements. Thus, the thermal radiation energy from a living being passing through the surveillance region reaches initially only one and subsequently only the other of the detector elements when such living being is entering, and initially only the other and subsequently only the one detector element when such living being is leaving, the controlled-access space. The opposite polarity electrical signals are then evaluated on the basis of their then existing lead/lag relationship.
REFERENCES:
patent: 3141612 (1964-07-01), Bolton
patent: 4000400 (1976-12-01), Elder
patent: 4263585 (1981-04-01), Schaefer
patent: 4303851 (1981-12-01), Mottier
patent: 4342987 (1982-08-01), Rossin
patent: 4346427 (1982-08-01), Blisset et al.
patent: 4523095 (1985-06-01), Keller-Steinbach
patent: 4612442 (1986-09-01), Toshimichi
patent: 4745284 (1988-05-01), Masuda et al.
F. Schwartz, "Performance of Narrow Field, Passive, Infra-Red Intrusion Detector", Proceedings of The Society of Photo-Optical, Sep. 1972, pp. 51-56.
Duong Tai V.
Heyman John S.
Otis Elevator Company
Ruzek Peter R.
LandOfFree
Directional people counting arrangement does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Directional people counting arrangement, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Directional people counting arrangement will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2416496