| US 7,502,001 B2 | ||
| Light emissive active matrix display devices with optical feedback effective on the timing, to counteract ageing | ||
| David A. Fish, Haywards Heath (United Kingdom); John M. Shannon, Whyteleafe (United Kingdom); Steven C. Deane, Redhill (United Kingdom); and Jason R. Hector, Redhill (United Kingdom) | ||
| Assigned to Koninklijke Philips Electronics N.V., Eindhoven (Netherlands) | ||
| Appl. No. 10/548,343 PCT Filed Feb. 27, 2004, PCT No. PCT/IB2004/000647 § 371(c)(1), (2), (4) Date Sep. 07, 2005, PCT Pub. No. WO2004/084168, PCT Pub. Date Sep. 30, 2004. |
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| Claims priority of application No. 0305632.2 (GB), filed on Mar. 12, 2003; and application No. 0317821.7 (GB), filed on Jul. 30, 2003. | ||
| Prior Publication US 2006/0208979 A1, Sep. 21, 2006 | ||
| Int. Cl. G09G 3/30 (2006.01) | ||
| U.S. Cl. 345—81 [345/207] | 25 Claims |
| 1. An active matrix display device comprising an array of display pixels, each pixel comprising:
a current-driven light emitting display element;
a drive transistor for driving a current through the display element;
a storage capacitor for storing a voltage to be used for addressing the drive transistor;
a discharge transistor for discharging the storage capacitor thereby to switch off the drive transistor; and
a light-dependent device for controlling the timing of the operation of the discharge transistor by varying the gate voltage
applied to the discharge transistor in dependence on the light output of the display element, wherein a discharge capacitor
is provided between the gate of the discharge transistor and a constant voltage line, and the light dependent device is for
charging or discharging the discharge capacitor.
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