The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 08, 1994
Filed:
Jan. 14, 1993
R Wendell Goodwin, Dunwoody, GA (US);
Schlumberger Industries, Inc., Norcross, GA (US);
Abstract
An optical sensor for monitoring position of a movable object comprising a LED and a phototransistor is provided with control circuitry, which is responsive to an output signal generated by the phototransistor for causing the LED to suspend radiation of light. When the light reflected from a reflective area of the object falls on the phototransistor, the control circuitry turns off the LED as soon as the output of the phototransistor goes below a threshold level signifying that the phototransistor has been turned on. When the light is absorbed by a non-reflective area of the object and the phototransistor is not turned on, the control circuitry turns off the LED after a predetermined time period, which is chosen to be slightly larger than the response time of the phototransistor.