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:
Sep. 22, 1998
Filed:
Jan. 30, 1997
Mohan L Kapoor, Orange, CT (US);
Thomas John Rebeschi, North Haven, CT (US);
Northrop Grumman Corporation, Los Angeles, CA (US);
Abstract
Pixel luminance of an electroluminescent display panel is controlled by a row driver applying a voltage equal to the panel's threshold voltage, and column drivers applying the voltage value above the threshold voltage to bring the pixel to the desired luminance. Each column driver independently samples a stepped ramp voltage signal at its own predetermined time selected as a function of the desired luminance. Each column driver then holds the sampled voltage value, and applies to its corresponding column electrode at the appropriate time a voltage equal to the sampled voltage value. The voltage rate of change of each individual step of the stepped ramped voltage signal can be controlled to vary the luminance levels, and to uniformly separate each of the luminance levels.