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. 15, 1982
Filed:
Aug. 25, 1980
William A Thornton, Jr, Cranford, NJ (US);
Edward Chen, Glen Rock, NJ (US);
Edward W Morton, Teaneck, NJ (US);
Dorothy Rachko, Passaic, NJ (US);
Westinghouse Electric Corp., Pittsburgh, PA (US);
Abstract
Method and apparatus for expressing as a number the relative brightness of artificial illumination as it is perceived by the average observer. There is extracted (i.e., detected) from the illumination to be measured, a blue-appearing narrow band, a green-appearing narrow band, a yellow-appearing narrow band and a red-orange-appearing narrow band. From these extracted bands are generated six different signals: a signal expressed as (aB) where (a) is about 0.23 and (B) is the watts of energy in the blue band, a signal expressed as (bG) where (b) is about 0.97 and (G) is the watts of energy in the green band, a signal expressed as (cR) where (c) is about 0.33 and (R) is the watts of energy in the red-orange band, a signal expressed as (dY) where (d) is about 0.19 and (Y) is the watts of energy in the yellow band, a signal expressed as (eG) where (e) is about 0.25 and (G) is the watts of energy in the green band, and a signal expressed as (fR) where (f) is about 0.25 and (R) is the watts of energy in the red-orange band. These signals are combined in the following manner: aB+bG+cR-dY+(the larger of eG and fR minus the smaller of eG and fR). These combined signals are expressed as a number which is indicative of the relative brightness of artificial illumination as perceived by the average observer.