System and method for color and intensity calibrating of a display system for practical usage

• US 9,497,447 B2
• Filed: 06/14/2012
• Issued: 11/15/2016
• Est. Priority Date: 06/15/2011
• Status: Active Grant

• Current Assignee: Scalable Display Technologies, Inc.
• Original Assignee: Scalable Display Technologies, Inc.
• Inventors: Green, Paul E., Surati, Rajeev J., Amaratunga, Kevin, Timoner, Samson J.
• Primary Examiner(s): McCulley, Ryan D
• Application Number:
  US13/523,852
• Publication Number:
  US 20120320042A1
• Time in Patent Office: 1,615 Days
• Field of Search: 345/589
• US Class Current: 1/1
• CPC Class Codes: G01J 3/506 measuring the colour produced by screens, monitors, displays or CRTs
• CPC Class Codes: G06T 7/90 Determination of colour characteristics
• CPC Class Codes: G09G 2320/0242 Compensation of deficiencies in the appearance of colours
• CPC Class Codes: G09G 2320/0693 Calibration of display systems
• CPC Class Codes: G09G 3/002 to project the image of a two-dimensional display, such as an array of light emitting or modulating elements or a CRT
• CPC Class Codes: G09G 3/2003 Display of colours specific for liquid crystal displays G09G3/3607
• CPC Class Codes: H04N 13/327 Calibration thereof
• CPC Class Codes: H04N 13/363 using image projection screens volumetric display H04N13/388
• CPC Class Codes: H04N 9/3147 Multi-projection systems displays in general H04N9/12; video walls G06F3/1446, G09G2300/026
• CPC Class Codes: H04N 9/3182 Colour adjustment, e.g. white balance, shading or gamut white balance per se H04N9/73; control of amplitude of colour signals H04N9/68; colour control circuits for displays in general G09G5/02, G09G3/2003, G09G3/3607
• CPC Class Codes: H04N 9/3194 including sensor feedback

Abstract

The invention provides a system and method that allows for the calibration of color and intensity in a display system in a manner that is practical for the user, and handling obscuring factors, giving the user the ability to make intelligent trade-offs, and making it possible to quickly and efficiently re-compute a correction. More generally, correction and adjustment of intensity and color non-uniformities, and using optical sensor feedback to detect and correct for those changes is contemplated. This includes, but is not limited to, showing very bright images and very dark images. This invention further provides methods for making a practical system for the user, including a method of calculating corrections, dealing with obscuring factors that can affect the calculation process, providing information to allow users to make decisions on how to make trade-offs on the quality factors of the display, and allowing fast re-calculation of intensity corrections when re-calibrating.

Claims

1. A method for correcting for obscuring factors on a screen comprising the steps of:

detecting, using one or more image sensors, obscuring factors on a screen, wherein detecting the obscuring factors on the screen comprises using a high-pass filter to locate dirt or contaminants;

creating a spatial weighting factor to ignore regions overlapping with the detected obscuring factors;

creating a target image; and

iteratively converging, using camera-based feedback, at least one of spatial intensity or color variations of a displayed image to the target image until a predetermined accuracy as measured by an error metric is achieved, wherein the error metric is defined in part based on a plurality of spatially varying weights and the spatial weighting factor.

2. The method as set forth in claim 1 further comprising converging, with an iterative algorithm, the spatial intensity or color variations to the target image using 0 or more iterations.

3. The method as set forth in claim 1 further comprising detecting dirt or contaminants on a screen containing the target image.

4. The method as set forth in claim 1 further comprising detecting dirt or contaminants on a camera lens or other fixed pattern noise on the camera.

5. The method as set forth in claim 1 further comprising detecting pixels on an edge of at least one of one or more display units overlapping other screen sources as obscuring factors.

6. A system for calibrating at least one of a spatial intensity and color variation in one or more display units comprising:

one or more light sensors that detect obscuring factors on a screen wherein detecting the obscuring factors on the screen comprises using a high-pass filter to locate dirt or contaminants; and

a processor that creates a spatial weighting factor to ignore regions overlapping with the detected obscuring factors, creates a target image, and iteratively converges, using camera-based feedback, at least one of spatial intensity and color variations of a displayed image to the target image until a predetermined accuracy as measured by an error metric is achieved, wherein the error metric is defined in part based on a plurality of spatially varying weights and the spatial weighting factor.

7. A non-transitory computer-readable medium storing instructions that, when executed by a computer, cause the computer to:

detect, using one or more image sensors, obscuring factors on a screen, wherein detecting the obscuring factors on the screen comprises using a high-pass filter to locate dirt or contaminants;

create a spatial weighting factor to ignore regions overlapping with the detected obscuring factors;

create a target image; and

iteratively converge, using camera-based feedback, at least one of spatial intensity and color variations of a displayed image to the target image until a predetermined accuracy as measured by an error metric is achieved, wherein the error metric is defined in part based on a plurality of spatially varying weights and the spatial weighting factor.