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:
Feb. 09, 1993
Filed:
Jul. 11, 1991
Ian Lewin, Scottsdale, AZ (US);
Ladd Howell, Scottsdale, AZ (US);
Lighting Sciences, Inc., Scottsdale, AZ (US);
Abstract
A portable traffic signal photometer is capable of rapidly and effectively measuring the intensity of light emanating from a traffic signal light. The photometer includes a housing member with a circular front opening for engagement with the lens of a traffic signal light. The photometer is pressed against the lens, and the light emanating from the traffic signal light is directed through an optical filter located inside the housing, which permits light from the traffic signal light emanating at a predetermined downward angle to pass through it. The light from the filter is directed onto a light-sensitive device, which produces an output signal proportional to the intensity of the light emitted by the traffic signal lens. Additional light-responsive photocells are provided to produce signals indicative of the respective color of the traffic signal light being measured by the photometer, and the composite of the color and the light intensity is used to produce a display which permits the user to determine whether the traffic signal light is properly operating within its designed specifications.