Flat-panel display assembled from pre-sorted tiles having matching color characteristics and color correction capability

• US 6,292,157 B1
• Filed: 04/20/1998
• Issued: 09/18/2001
• Est. Priority Date: 03/25/1996
• Status: Expired due to Term

• Current Assignee: Hanger Solutions, LLC (IP Investments Group LLC)
• Original Assignee: Rainbow Displays, Inc.
• Inventors: Greene, Raymond G., Katyl, Robert H., Yost, Boris, Krusius, J. Peter
• Primary Examiner(s): Saras, Steven
• Assistant Examiner(s): Bell, Paul A.
• Application Number:
  US09/063,321
• Time in Patent Office: 1,247 Days
• Field of Search: 345/1, 345/32, 345/55, 345/87, 345/88, 345/90, 345/103, 345/903, 348/383, 348/751, 348/791, 349/106, 349/109, 349/112, 358/518-523, 324/770
• US Class Current: 345/1.3
• CPC Class Codes: G09G 2300/026 Video wall, i.e. juxtaposition of a plurality of screens to create a display screen of bigger dimensions
• CPC Class Codes: G09G 2310/0221 with use of split matrices G09G3/3644 and G09G3/3666 take precedence
• CPC Class Codes: G09G 2320/0233 Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 2320/0242 Compensation of deficiencies in the appearance of colours
• CPC Class Codes: G09G 2320/0285 using tables for spatial correction of display data
• CPC Class Codes: G09G 3/2003 Display of colours specific for liquid crystal displays G09G3/3607
• CPC Class Codes: G09G 3/3607 for displaying colours or for displaying grey scales with a specific pixel layout, e.g. using sub-pixels display of colours in flat matrix panels other than liquid crystal displays G09G3/2003; grey scales specific for television H04N3/127
• CPC Class Codes: G09G 3/3666 with the matrix divided into sections
• CPC Class Codes: H04N 9/12 Picture reproducers H04N9/11 takes precedence
• CPC Class Codes: Y10S 345/903 Modular display

Abstract

The present invention features a tiled, flat-panel, color display that has a color-correction capability. The display is a tiled mosaic of individual display tiles, such as AMLCDs. Column and row inputs that are typically provided for a single display tile system are distributed over a plurality of display tiles. The color purity is achieved for the display by sorting the tiles into groups, matching their color coordinates, and correcting non-uniformities optically (e.g., by using a graded neutral density filter having a grading function being the inverse of the brightness distribution non-uniformities) and/or electronically. Then, each individual tile in the mosaic is color-corrected via a multiplexed, controller/driver circuit.

Claims

1. A tiled, substantially flat, panel display with color-correction capability, comprising:

a mosaic of individual display tiles of a given number, said tiles, when assembled, providing a monolithic display having visually imperceptible seams, said display tiles having column and row inputs that are provided for a single display tile system, said column and row inputs being distributed over said given number of tiles using matrix addressing, said display tiles being sorted into groups that have substantially matching color coordinates prior to assembly into a display, with each individual tile in the mosaic having its own set of characteristics;

graded neutral density filter disposed adjacent said mosaic, said graded neutral density filter having a grading function that represents the inverse of brightness distribution non-uniformities in the display;

means defining a video input signal; and

controller/driver means connected to said mosaic for selectively applying said video input signal to said mosaic, so that color purity is maintained over substantially all of said individual display tiles, whereby the imperceptibility of said visually imperceptible seams is enhanced.

2. The tiled, substantially flat, panel display with color-correction capability in accordance with claim 1, further comprising means for balancing said video input, wherein average tile brightness is achieved by modifying a level of said video input with a predetermined tile-dependent set of parameters.

3. The tiled, substantially flat, panel display with color-correction capability in accordance with claim 1, wherein said inverse of the color non-uniformities in the display will substantially match the brightness levels across the entire display, and wherein the dimmest regions of the display have the least reduction.

4. The tiled, substantially flat, panel display with color-correction capability in accordance with claim 1, further comprising means for electronically modifying the video input, wherein brightness levels across the entire display will be substantially matched.

5. The tiled, substantially flat, panel display with color-correction capability in accordance with claim 1, wherein said mosaic is defined as a selected, substantially matched set of display tiles having the intra-tile average values of brightness and color for each color fall within a specified range for each display tile.

6. The seamless, tiled, substantially flat, panel display with color-correction capability in accordance with claim 1, wherein said graded neutral density has a minimum optical density at the dimmest region of said display.

7. The seamless, tiled, substantially flat, panel display with color-correction capability in accordance with claim 1, wherein said mosaic is defined as a selected, substantially matched set of display tiles having the intra-tile average values of brightness and color for each color fall within a specified range for each display tile.

8. The seamless, tiled, substantially flat, panel display with color-correction capability in accordance with claim 2, wherein said display tiles are LCDs and wherein said tile-dependent set of parameters that determine the display characteristics of each tile comprises any of the elements taken from the set of:

a) threshold voltage values of a pixel;

b) maximum/minimum transmissivities of a pixel;

c) pixel voltage optical gains;

d) color coordinates; and

e) tile edge-related parameters.