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. 28, 1989
Filed:
Oct. 24, 1988
Robert A Simms, Phoenix, AZ (US);
Murasa International, Long Beach, CA (US);
Abstract
A safety light responsive shutoff switch is provided for a hand-held infrared laser light source to prevent irreparable eye damage to persons who may inadvertently look into the light exit opening of the laser light source while it is operating. This is accomplished by concentrically mounting normally-closed infrared light responsive photoelectric Darlington safety switches around the light exit end of the light source. Light reflected from the laser light source off an object intruding into the laser beam within a danger zone (typically zero inches to ten inches from the light exit opening) produces reflected light at the frequency of the laser light source of sufficient intensity to operate the photoelectric Darlington safety switch devices to turn off the power supply to the laser light source. Light reflected from objects which are outside of the danger zone is of insufficient intensity to operate the light responsive safety switches.