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:
Nov. 20, 1990
Filed:
Apr. 03, 1989
David W Stevenson, Chandler, AZ (US);
Motorola Inc., Schaumburg, IL (US);
Abstract
An improved electro-optic transmitter-receiver is provided by arranging a variable light source such as an LED and a photosensitive device, such as a phototransistor, on one or more parts of a substantially flat leadframe. Both the variable light source and photosensitive device face outwardly in the same direction approximately perpendicular to the plane of the package leads. A unitary transparent cover extends over the variable light source and the photosensitive device. A lense is provided over the photosensitive device that does not extend over the variable light source. An NPN phototransistor is desirable for the photosensitive device and is mounted on the central device lead substantially centered under the centrally located lense. When an N-substrate LED is used it is conveniently located on another lead to one side of the lense. The LED may also be located on the same lead as the phototransistor, but not under the lense. Wire bonding is conveniently used to connect the devices to form a three terminal electro-optic transmitter-receiver. It is desirable to have a recess extending into the cover between the LED and the phototransistor to reduce transmission of internally back-scattered light therebetween.