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:
Jul. 18, 1989
Filed:
Jun. 30, 1987
Robert W Massof, Baltimore, MD (US);
LKC Technologies, Inc., Gaithersburg, MD (US);
Abstract
To provide for an easy and accurate color vision tester, a plurality of yellow, red and green lights are mounted, or projected, onto a display, with the yellow lights providing for the background luminance while the red and green lights providing for a mixture of red and green luminance. Different patterns on the display are formed by a combination of the red and green lights. A particular pattern can be selected from among the various patterns by a pattern select circuit. The intensity of the red to green lights can be inversely varied so that different ratios of intensity for the selected pattern may be presented to an observer. Each of these ratios corresponds to a certain type of color vision. Therefore, by determining whether an observer is able to discern the pattern from the background in a particular intensity setting, the type of color vision an observer has can easily be ascertained.