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:
Jul. 23, 1991
Filed:
Sep. 21, 1989
Charles M Hammond, Jr, Skaneateles, NY (US);
Welch Allyn, Inc., Skaneateles Falls, NY (US);
Abstract
An optical reader is designed to be insensitive to specular reflection, particularly at tapered lead-in areas to the left and right of a coded record on a record member. The optical reader includes a photosensor that is oriented with its optical axis along the reader optical center line so as to be situated substantially perpendicular to the record member passing through a reader slot. There are upper and lower LEDs only, which are disposed respectively on opposite sides of the optical center line in a vertical plane. That is, the LEDs lie in a plane perpendicular to the path of a record member being swiped through the slot. In this way, no specular reflection at the lead-in areas will fall onto the photosensor. In addition, the effect of specular reflection occurring at areas of the record member in a plane perpendicular to its path of travel is reduced by a factor of two over an optical reader using a single LED.