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:
Apr. 26, 1994
Filed:
Feb. 02, 1993
Richard B Dingwall, Rochester, NY (US);
Lowell W Knapp, Victor, NY (US);
John H Steele, Spencerport, NY (US);
James S Celebi, Holcomb, NY (US);
Virgil J Hull, Fairport, NY (US);
Xerox Corporation, Stamford, CT (US);
Abstract
A liquid crystal display unit is provided which includes a primary, image-defining display and a secondary display, arranged in series with the primary display. The primary and secondary displays have equal numbers of light shutters, similarly sized and located on each display, so that when the corresponding light shutters on the primary and secondary displays are closed, substantially no light passes through the viewing side of the primary display. An opaque mask is formed on the input side of the primary display to define the shape of the image elements to be displayed. This mask covers the edges of the primary display light shutters to define the image elements display. This mask permits the primary and secondary displays to be easily aligned with each other. Color patches can be located on the light input side of the primary display light shutters so that the viewed images are in color. The use of the opaque mask to form the image elements eliminates the need to form precisely shaped color patches. Since and the mask blocks all light between light shutters, a display is provided having a true dead front. The true dead front display permits colored text displays using mimic-type electrodes to be produced. Since the secondary displays need not perform as well as the primary displays, displays which are not suitable for use as primary displays can be used as the secondary displays.