Controller circuit for liquid crystal matrix display devices

• US 20010024199A1
• Filed: 03/21/2001
• Published: 09/27/2001
• Est. Priority Date: 03/22/2000
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: US Philips Corporation (Koninklijke Philips N.V.)
• Inventors: Hughes, John R., Parker, David W.
• Granted Patent: US 6,624,800 B2
• Time in Patent Office: Days
• US Class Current: 345/204
• CPC Class Codes: G09G 2320/0219 Reducing feedthrough effects in active matrix panels, i.e. voltage changes on the scan electrode influencing the pixel voltage due to capacitive coupling
• CPC Class Codes: G09G 2320/0252 Improving the response speed
• 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 2320/0276 for the purpose of adaptation to the characteristics of a display device, i.e. gamma correction
• CPC Class Codes: G09G 2340/16 Determination of a pixel data signal depending on the signal applied in the previous frame
• CPC Class Codes: G09G 3/3611 Control of matrices with row and column drivers
• CPC Class Codes: G09G 3/3614 Control of polarity reversal in general
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: G09G 5/06 using colour palettes, e.g. look-up tables

Abstract

A controller circuit (24) for processing video data for an active matrix liquid crystal display device has processing circuitry for performing correction functions on the input video data (D) prior to being supplied to the drive circuit (22) of the display device comprising gamma and color correction, and correction for reducing motion blur in the display picture. The correction circuits (35, 36) are organized such that correction for motion blur reduction (36) is carried out before the gamma and color corrections (35), which enables a beneficial decrease in semiconductor area required when implementing the circuitry in IC form through the size of field store (30) and LUT (32) components used for this function then being smaller. Gamma and color corrections are performed together using a single LUT. Correction for kickback may further be included, such correction preferably being arranged after the gamma and color corrections and using a separate LUT.

Claims

1. A controller circuit for processing video data for a colour active matrix liquid crystal display device and having an input for video data, processing circuitry for processing the video data and an output from which the processed video data is provided for supply to a driver circuit of the display device, wherein the processing circuitry comprises gamma and colour correction circuits which include a Look-Up Table, and a motion blur reduction circuit for modifying the video data so as to reduce perceived blurring in moving images displayed on the display device and comprising a field store for video data and a Look-Up Table, and wherein the motion blur reduction circuit precedes the gamma and colour correction circuits.

2. A controller circuit according to

claim 1

, wherein the controller circuit further includes a kickback correction circuit for modifying the video data so as to correct for kickback effects in the display device pixels and which is arranged following the motion blur reduction circuit.

3. A controller circuit according to

claim 2

, wherein the kickback correction circuit follows also the gamma and colour correction circuits.

4. A controller circuit according to any one of the preceding claims, wherein the controller circuit is in the form of one or more integrated circuits.

5. An active matrix liquid crystal display system comprising an active matrix liquid crystal display device and a controller circuit according to any one of

claims 1

to

4

, and in which the output of the controller circuit is connected to a drive circuit of the display device.