METHOD AND APPARATUS IN VARIOUS EMBODIMENTS FOR HDR IMPLEMENTATION IN DISPLAY DEVICES

• US 20090322800A1
• Filed: 06/25/2009
• Published: 12/31/2009
• Est. Priority Date: 06/25/2008
• Status: Abandoned Application

• Current Assignee: Dolby Laboratories Licensing Corporation (Dolby Laboratories Incorporated)
• Original Assignee: Dolby Laboratories Licensing Corporation (Dolby Laboratories Incorporated)
• Inventors: Atkins, Robin
• Application Number:
  US12/491,857
• Publication Number:
  US 20090322800A1
• Time in Patent Office: Days
• US Class Current: 345/690
• CPC Class Codes: G09G 2330/045 Protection against panel overheating
• CPC Class Codes: G09G 3/006 Electronic inspection or testing of displays and display drivers, e.g. of LED or LCD displays testing individual LED's G01R31/2635; testing lamps G01R31/44; testing of optical features of LCD displays G02F1/1309
• CPC Class Codes: G09G 3/2014 by modulation of the duration of a single pulse during which the logic level remains constant
• CPC Class Codes: G09G 3/2018 by time modulation using two or more time intervals
• CPC Class Codes: G09G 3/3413 Details of control of colour illumination sources
• CPC Class Codes: G09G 3/3426 the different display panel areas being distributed in two dimensions, e.g. matrix
• CPC Class Codes: G09G 5/10 Intensity circuits

Abstract

An HDR display is a combination of technologies including, for example, a dual modulation architecture incorporating algorithms for artifact reduction, selection of individual components, and a design process for the display and/or pipeline for preserving the visual dynamic range from capture to display of an image or images. In one embodiment, the dual modulation architecture includes a backlight with an array of RGB LEDs and a combination of a heat sink and thermally conductive vias for maintaining a desired operating temperature.

Claims

1. A backlight for a display, comprising:

a plurality of LEDs arranged on a first side of thermally conductive substrate;

a heat sink disposed on an opposite side of the substrate;

a series of heat conductive vias thermally connecting each LED to the heat sink;

wherein;

the heat conductive vias comprise copper plated holes in the substrate;

the thermally conductive substrate comprising thick power and ground planes dispersed throughout the substrate; and

thermal conductivity of the vias are approximately 400 W/m·

K.

2. The backlight according to claim 1, wherein the backlight is configured to project an approximation of an image onto a modulator.

3. The backlight according to claim 1, wherein the backlight is part of a high dynamic range display.

4. The backlight according to claim 1, wherein the backlight is configured to produce an approximation of a desired image and project the image onto a second modulator wherein light emitted by the LEDs is mixed such that the approximation of the desired image is created by a smoothly varying lightfield between the LEDs.

5. The backlight according to claim 1, wherein the backlight LEDs are configured as a first modulator in a dual modulation display that uses a distance between the LEDs and a second modulator to produce a smoothly varying backlight projected onto the second modulator.

6. The backlight according to claim 1, wherein the backlight is installed in a dual modulation display without cooling fans.

7. The backlight according to claim 1, further comprising a non-color changing reflective material configured to direct light away from the heat sink.

8. The backlight according to claim 1, wherein the backlight is a modulator in a multi-modulation HDR display comprising a processor configured to perform color correction by accounting for the native color temperature of the HDR display.

9. The backlight according to claim 1, wherein the heat sink and thermal properties of the backlight are designed to maintain an optimal temperature for at least one of LED life and a desired color temperature of the LEDs.

10. A multi-modulation display comprising a backlight having a heat sink and other thermally conductive materials configured to maintain a constant operating temperature of the backlight.

11. The multi-modulation display according to claim 10, wherein the constant operating temperature comprises a temperature that maximizes backlight longevity.

12. The multi-modulation display according to claim 10, wherein the constant operating temperature comprises a temperature that maintains a desired color temperature of the backlight.

13. The multi-modulation display according to claim 11, wherein the backlight comprises an array a LEDs comprising a first modulator, an LCD panel comprises a second modulator, and the first modulator if configured to produce an approximation of the desire image and project it onto the second modulator which is configured to further modulate the approximated image to produce a desired image.

14. The multi-modulation display according to claim 10, wherein the constant operating temperature comprises a temperature that maintains a temperature of optimal efficiency of the backlight.

15. The multi-modulation display according to claim 14, wherein the optimal efficiency is an optimal efficiency of an LED of the backlight.

16. The multi-modulation display according to claim 10, further comprising a modulator configured to, during operation of the display, further modulate light emitted from the backlight.

17. The multi-modulation display according to claim 16, wherein the modulator comprises a passive modulator.

18. The multi-modulation display according to claim 17, wherein the passive modulator comprises an LED panel.

19. A High Dynamic range display comprising:

A backlight comprising an active array of RGB LEDs, and a passive modulator comprising an LCD panel including a series a RGB filters matched to the wavelengths of the RGB LEDs, wherein the backlight further comprises a heat sing and thermally conductive vias for maintaining a desired temperature during operation of the display.

20. The HDR display according to claim 19, further comprising a temperature mechanism configured to monitor an operating temperature of the backlight.