Compensation for color variations in emissive devices

• US 10,181,282 B2
• Filed: 01/22/2016
• Issued: 01/15/2019
• Est. Priority Date: 01/23/2015
• Status: Active Grant

• Current Assignee: IGNIS Innovation Incorporated
• Original Assignee: IGNIS Innovation Incorporated
• Inventors: Chaji, Gholamreza
• Primary Examiner(s): Elahi, Towfiq
• Application Number:
  US15/004,398
• Publication Number:
  US 20160217734A1
• Time in Patent Office: 1,089 Days
• CPC Class Codes: G09G 2300/0452 Details of colour pixel setup, e.g. pixel composed of a red, a blue and two green components
• CPC Class Codes: G09G 2320/0242 Compensation of deficiencies in the appearance of colours
• CPC Class Codes: G09G 2320/0666 for control of colour parameters, e.g. colour temperature
• CPC Class Codes: G09G 2340/06 Colour space transformation
• CPC Class Codes: G09G 3/2003 Display of colours specific for liquid crystal displays G09G3/3607
• CPC Class Codes: G09G 3/3225 using an active matrix

Abstract

What is disclosed are methods and systems for color compensation in the context of emissive displays. A set of virtual sub-pixels are defined and color points allocated for the various types of virtual sub-pixels to enable color processing within a modified color gamut, shifting the color of pixels to the modified color gamut to improve a perceived quality color rendered by the display.

Claims

1. A method of color compensation for an emissive display comprising a plurality of physical pixels, each physical pixel including physical sub-pixels of a plurality of physical sub-pixel types, the method comprising:

defining a plurality of virtual sub-pixel types from the physical sub-pixel types based on the colors of the physical sub-pixel types, each virtual sub-pixel type defined by one or more of the physical sub-pixel types, the plurality of virtual sub-pixel types for defining a color gamut different from a color gamut defined by the colors of the physical sub-pixels;

defining for each physical pixel, a single virtual sub-pixel corresponding to each virtual sub-pixel type of the plurality of virtual sub-pixel types, each virtual sub-pixel consisting of one or more physical sub-pixels of the physical pixel according to the definition of the virtual sub-pixel type corresponding to the virtual sub-pixel;

characterizing the light output across the display, generating light output data;

for each virtual sub-pixel type, allocating a color point to the virtual sub-pixel type based on the light output data;

performing color calculations with use of the color points of each virtual sub-pixel type to generate virtual sub-pixel brightness values;

mapping virtual sub-pixel brightness values to physical sub-pixel values.

2. The method of claim 1 further comprising accumulating for each physical sub-pixel a physical sub-pixel value from contributions from mapping the virtual sub-pixel brightness values.

3. The method of claim 2 wherein characterizing the light output across the display comprises measuring actual color points of the physical sub-pixels, and wherein the color point allocated to each virtual sub-pixel type is determined with use of the measurements of the actual color points of the physical sub-pixels.

4. The method of claim 3 wherein the measuring the actual color points of physical sub-pixels comprises determining at least one non-uniformity for a threshold number of physical sub-pixels.

5. The method of claim 3 wherein the color points allocated to the virtual sub-pixel types defines the color gamut, which is smaller than a color gamut of physical pixels of the display exhibiting the greatest color accuracy.

6. The method of claim 3 wherein the color points allocated to the virtual sub-pixel types are utilized in the mapping of virtual sub-pixel brightness values to physical sub-pixel values in order to reduce color nonuniformity across the emissive display.