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:
Mar. 24, 1987
Filed:
Nov. 07, 1983
Ian Lewin, Scottsdale, AZ (US);
Other;
Abstract
An improved traffic signal lamp control system utilizes continuously burning lamps, such as fluorescent lamps or HID lamps, located inside a traffic signal housing or external to the housing to direct light toward the lens apertures of the housing. A light attentuation device, which may be either a mechanical shutter or a liquid crystal panel is placed in the path of light between the continuously energized lamp and the aperture of the housing to either block the passage of light from the lamp through the aperture or permit the passage of light therethrough. The conventional red, amber and green lenses are placed in the apertures, and the conventional traffic signal light control signals are used to operate the attentuation device. Substantial savings in power consumption are encountered since fluorescent lamps and HID lamps consume much less power than incandescent lamps, and considerably increased lamp life can be achieved. When a liquid crystal shutter is used for the attenuation device, the switching is accomplished by low-voltage switching.