Photoelectric controlling

Details Photoelectric controlling Photoelectric controlling

1975-07-28

1976-12-07

Smith, Alfred E.

Radiant energy

Photocells; circuits and apparatus

Signal isolator

250213A, 307311, G02B 2700, H03K 342

Patent

active

039964752

ABSTRACT:
A light source, such as a light emitting diode (LED), illuminates a cadmium sulfide or cadmium selenide photocell to lower its resistance and thereby initiate conduction in a solid-state device, such as a silicon controlled rectifier (SCR), to deliver current to a load that is interrupted by removing the light energy and restoring the photocell to its unilluminated high resistance state. A feature of the invention resides in limiting the optical energy incident upon the photocell so that its resistance remains well above the lowest resistance it can attain while still dropping to a resistance value considerably below its maximum resistance when unilluminated so that within the total resistance changes of the photocell, the small percentage resistance charge required for proper activation of the solid-state device, may be effected relatively rapidly both for turn on and turn off.

REFERENCES:
patent: 3476941 (1969-11-01), Bonin
patent: 3524986 (1970-08-01), Harnden, Jr.
patent: 3693060 (1972-09-01), Joyce
patent: 3708672 (1973-01-01), Marinkovic
patent: 3866051 (1975-02-01), Shearer et al.

Affiliated with

Also associated with

Rating

Photoelectric controlling does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Photoelectric controlling, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Photoelectric controlling will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-381197