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:
Jun. 01, 1999
Filed:
Feb. 02, 1998
Paul D Hiltman, Atlanta, GA (US);
International Safety Instruments, Inc., Lawrenceville, GA (US);
Abstract
Light is directed towards at least one eye of a user of a personal alert safety system (PASS), and the reflected light is sensed. When the eye blinks, there is an interruption of the reflected light signal indicating that the user is conscious. Electronic circuitry converts the variation in reflected light intensity into a corresponding variation in electrical signal. The PASS interprets this variable electrical signal as a reset indicator, so that as long as the wearer is conscious, the audio warning alarm in the PASS does not sound. The light is provided by a light emitting diode in the near infrared range, and the reflected beam may be sensed by a photodiode or phototransistor. Alternatively, ultra sound, or other light frequencies, may be used.