Display device

• US 20020149574A1
• Filed: 02/14/2002
• Published: 10/17/2002
• Est. Priority Date: 02/16/2001
• Status: Active Grant

• Current Assignee: InnoLux Corporation
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Johnson, Mark Thomas, Nauta, Tore
• Granted Patent: US 7,109,963 B2
• Time in Patent Office: Days
• US Class Current: 345/204
• CPC Class Codes: G02F 1/133382 Heating or cooling of liquid crystal cells other than for activation, e.g. circuits or arrangements for temperature control, stabilisation or uniform distribution over the cell
• CPC Class Codes: G02F 1/136213 Storage capacitors associated with the pixel electrode
• CPC Class Codes: G09G 2320/0261 in the context of movement of objects on the screen or movement of the observer relative to the screen
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: G09G 3/3603 with thermally addressed liquid crystals
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: G09G 3/3659 the addressing of the pixel involving the control of two or more scan electrodes or two or more data electrodes, e.g. pixel voltage dependant on signal of two data electrodes

Abstract

The response of the last addressed lines in a pulsed backlight LCD is enhanced by introducing overdrive at these last lines, for instance, via capacitive coupling or by means of a temperature gradient.

Claims

1. A display device comprising a pixel and at least one switching element at the area of a matrix of selection electrodes and data electrodes, and drive means for driving the selection electrodes in a sequence and for driving and for driving the data electrodes, wherein the display device comprises a pulsed backlight system and further means for increasing the switching rate of pixels in the sequence of selecting the pixels during operation.

2. A display device as claimed in claim 1, wherein the further means comprise drive means for increasing the range of possible drive voltages across the pixels in the sequence of selecting the pixels.

3. A display device as claimed in claim 1, wherein a picture electrode of a pixel is capacitively coupled to a further electrode, and the further means comprise drive means for increasing the range of possible drive voltages across the pixels via the capacitive coupling.

4. A display device as claimed in claim 3, wherein the drive means apply drive voltages across the pixels via a capacitive coupling with a juxtaposed selection electrode.

5. A display device as claimed in claim 3 or 4, wherein the capacitances of the storage capacitors increase in the sequence of selecting the pixels.

6. A display device as claimed in claim 3 or 4, wherein the capacitances of the storage capacitors decrease in the sequence of selecting the pixels.

7. A display device as claimed in claim 1, wherein the further means comprise heating means for generating a temperature gradient during operation, at which the temperature increases in the direction of the sequence of selecting the pixels.