Optical sensor circuitry

Details Optical sensor circuitry Optical sensor circuitry

1986-09-09

1988-04-26

Tarcza, Thomas H.

Radiant energy

Photocells; circuits and apparatus

Photocell controlled circuit

H01J 4014

Patent

active

047406860

ABSTRACT:
A photo sensor circuit including an LED (12) and a phototransistor (14) coupled together by resistors (R.sub.1, R.sub.2) and connected to a drive and sense network (16) including resistors (R.sub.B, R.sub.3, R.sub.4), a source of positive voltage (+Vcc) and a PNP transistor (20) by a single conductor wire (W.sub.1). When the light path between the LED (12) and the phototransistor (14) is blocked, the circuit standby current is low and the transistor (20) is OFF, but when the light blockage is removed, the increase in current through the LED (12), triggered by an increase in current through the phototransistor (14) quickly drives the transistor (20) into saturation. The phototransistor (14) will keep full current flowing through the LED (12) as long as the light blockage is removed. This circuit enables selected resistances for appropriate standby current for one selected photo sensor network to be used with various networks of LEDs and phototransistors with varying component parameters and also reduces the current drain by one-third to one-fourth the current drain of conventional photo sensor circuitry.

REFERENCES:
patent: 3770966 (1973-11-01), Sagawa et al.
patent: 3956628 (1976-05-01), Hanger
patent: 4074143 (1978-02-01), Rokos
patent: 4097731 (1978-06-01), Krause et al.
patent: 4203032 (1980-05-01), Haunstetter et al.
patent: 4247765 (1981-01-01), Bergstrom
patent: 4247790 (1981-01-01), Sahasrabudhe et al.
patent: 4270045 (1981-05-01), Werking
patent: 4281325 (1981-07-01), Jarva
patent: 4300211 (1981-11-01), Hudson
patent: 4352013 (1982-09-01), Fasig et al.
patent: 4376277 (1983-03-01), Black, Jr.
patent: 4521681 (1985-06-01), Inaba et al.
patent: 4577096 (1986-03-01), Beery et al.
patent: 4580044 (1986-04-01), Hongo et al.
patent: 4605848 (1986-08-01), Ogawa
patent: 4643571 (1987-02-01), Ferber et al.
patent: 4652742 (1987-04-01), Wauer et al.

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