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:
Sep. 20, 1988
Filed:
Feb. 06, 1987
William G Shumate, Tempe, AZ (US);
Burr-Brown Corporation, Tucson, AZ (US);
Abstract
An apparatus for selective backlighting individual transluscent keys of a terminal keyboard includes a horizontal, double-sided printed circuit board having a number of right angle LEDs equal to the number of backlit keys mounted on its bottom surface. A plurality of clearance holes in the printed circuit board admit a plurality of vertical light pipes that are integral with a transparent substrate. Integral alignment bosses on a bottom surface of the substrate fit precisely in corresponding holes of the printed circuit board. Each light pipe has a rectangular cross section and a 45 degree inclined bottom surface. A horizontal light beam emitted by a LED passes through a vertical wall of a light pipe, strikes its inclined bottom surface, and is reflected up through the light pipe into a recess within a key. The substrate supports a rubber sheet in which the keys are molded and a switch contact layer with printed conductors thereon. Depression of a key presses a conductive shorting pad against the printed conductors, actuating a switch.