SYSTEM AND METHOD FOR COLOR AND INTENSITY CALIBRATING OF A DISPLAY SYSTEM FOR PRACTICAL USAGE

• US 20120320042A1
• Filed: 06/14/2012
• Published: 12/20/2012
• Est. Priority Date: 06/15/2011
• Status: Active Grant

• Current Assignee: Scalable Display Technologies, Inc.
• Original Assignee: Scalable Display Technologies, Inc.
• Inventors: Surati, Rajeev J., Amaratunga, Kevin, Timoner, Samson J., Green, Paul E.
• Granted Patent: US 9,497,447 B2
• Time in Patent Office: Days
• US Class Current: 345/419
• 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 calibrating spatial intensity and/or color variations in one or more unit displays of a system using one or more light sensors comprising the steps of:

a. calculating a target image using the display units; and

converging, with an iterative algorithm, at least one of spatial intensity and color variations to the target image, the iterative algorithm applying 1 or more iterations when a predetermined accuracy is unachieved.

2. The method as set forth in claim 1 further comprising modifying at least some OMTE parameters of the system.

3. The method as set forth in claim 1 further comprising providing an injection function.

4. The method as set forth in claim 1 wherein the unit displays are projectors.

5. The method as set forth in claim 1 further comprising providing to the system a stereo image with one of more images adapted to reach each eye of a viewer.

6. A method for calibrating the spatial intensity and/or color variations in one or more unit displays comprising the steps of:

providing one or more light sensors; and

detecting obscuring factors and their affects by weighting one or more predetermined regions differently than other regions in the calculation of a desired target image of the display.

7. The method as set forth in claim 6 further comprising converging, with an iterative algorithm, the spatial intensity and/or color variations to the target image using 0 or more iterations.

8. The method as set forth in claim 6 further comprising detecting dirt or contaminants on a screen containing the target image.

9. The method as set forth in claim 6 further comprising detecting dirt or contaminants on a camera lens or other fixed pattern noise on the camera.

10. The method as set forth in claim 6 further comprising detecting pixels on an edge of the display overlapping other screen sources as obscuring factors.

11. A method for calibrating the spatial intensity and/or color variations in one or more unit displays comprising the steps of:

providing one or more light sensors; and

providing a user interface that includes a selection option for a trade-off between a plurality of quality factors in a target image.

12. The method as set forth in claim 11 where the trade-off is between intensity smoothness and brightness and further comprising providing an interface slider for the user to choose a trade-off operating point.

13. The method as set forth in claim 11 wherein the trade-off is between intensity smoothness and brightness and a plot is provided for a user to choose a trade-off operating point.

14. The method as set forth in claim 11 wherein the trade-off is between one of (a) brightness and (b) color or intensity variations.

15. The method as set forth in claim 11 where the trade-off is between computation time and quality of the converged result.

16. The method as set forth in claim 11 where the trade-off is the quality of the system in one spatial region over another spatial region.

17. A method for calibrating spatial intensity and/or color variations in one or more unit displays of a system using one or more light sensors comprising the steps of:

calculating derivatives of measurements in the light sensors with respect to motion of the cameras and the movement of the light sensors;

estimating measurements of motion of the unit displays and movement in the light sensors; and

estimating, with the initial photometric calibration data before movement, the motion, and the derivatives, a new desired correction of the system.

18. The method as set forth in claim 17 wherein the light sensors are one or more cameras.

19. The method as set forth in claim 17 wherein the light sensors are one or more projectors.

20. The method as set forth in claim 17 further comprising converging, with an iterative procedure, the spatial intensity and/or color variations to the target image.

21. A system for calibrating the spatial intensity and/or color variations in one or more unit displays comprising the steps of:

one or more light sensors; and

a process/processor that detects obscuring factors and their affects by weighting one or more predetermined regions differently than other regions in the calculation of a desired target image of the display.