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:
Aug. 10, 1999
Filed:
Nov. 02, 1998
Robert T Smith, Tempe, AZ (US);
Ken K Foo, Chandler, AZ (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A field emission display (100) includes a cathode plate (104) having a plurality of electron emitters (112) and ballast resistors (118), an anode plate (120) having an anode (124), and a temperature compensation circuit (130) having an input (142), an output (134), and a current output (138). Input (142) is connected to unregulated voltage (132), output (134) is connected to gate (116), and current output (138) is connected to temperature sensing element (148). Preferably, temperature sensing element (148) is mounted on cathode plate (104) and matches the temperature vs. resistance characteristics of ballast resistors (118). Temperature compensation circuit (130) outputs current (220) to temperature sensing element (148) and receives ballast voltage (230) from temperature sensing element (148) as a function of temperature of cathode plate (104). Temperature compensation circuit (130) outputs gate voltage (238) to adjust electron emission current (114), and subsequently brightness for variations in temperature.