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. 07, 1978
Filed:
Sep. 27, 1976
Erick Schumacher, Sepulveda, CA (US);
Industrial Electronic Engineers, Inc., Van Nuys, CA (US);
Abstract
A projection device for selectively projecting one of a large number of images. A stepper motor operatively positions a selected transparency on a cartridge, containing a plurality of transparencies, within a projection system for illumination and projection of the image from the transparency onto a viewing screen. Apparatus is provided for automatically identifying the transparency cartridge which is being controlled by the stepper motor and for determining a homing position. The stepper motor always returns the cartridge to a starting or home position before moving the number of steps required to locate the selected transparency within the projection system.