Transparent display backlight assembly

• US 10,254,464 B2
• Filed: 11/02/2016
• Issued: 04/09/2019
• Est. Priority Date: 12/23/2010
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Inventors: Bohn, David D., Fleck, Rod G., Knee, Derek Leslie
• Primary Examiner(s): Han, Jason M
• Application Number:
  US15/341,881
• Publication Number:
  US 20170068039A1
• Time in Patent Office: 888 Days
• Field of Search: 362600-634
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: G02B 6/0033 Means for improving the coupling-out of light from the light guide
• CPC Class Codes: G02B 6/0035 provided on the surface of the light guide or in the bulk of it
• CPC Class Codes: G02B 6/0036 2-D arrangement of prisms, protrusions, indentations or roughened surfaces
• CPC Class Codes: G02B 6/0041 provided in the bulk of the light guide
• CPC Class Codes: G02B 6/0043 provided on the surface of the light guide
• CPC Class Codes: G02B 6/0053 Prismatic sheet or layer; Brightness enhancement element, sheet or layer
• CPC Class Codes: G02B 6/0068 Arrangements of plural sources, e.g. multi-colour light sources
• CPC Class Codes: G02B 6/0073 Light emitting diode [LED]
• CPC Class Codes: G02B 6/0076 Stacked arrangements of multiple light guides of the same or different cross-sectional area
• CPC Class Codes: G02F 1/133342 for double-sided displays
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side
• CPC Class Codes: G02F 1/133622 Colour sequential illumination
• CPC Class Codes: G02F 2203/01 transmissive
• CPC Class Codes: Y10S 977/834 Optical properties of nanomaterial, e.g. specified transparency, opacity, or index of refraction

Abstract

In embodiments of a transparent display backlight assembly, a backlight panel is operable as a transparent panel, and a light source generates light that the backlight panel directs from the light source to illuminate a display panel of a display device. Light refraction features refract and scatter the light, where the light refraction features are spaced for approximate transparency of the backlight panel and to illuminate the display panel. An active diffuser can be implemented as an additional transparent panel and operable for activation to diffuse the light from the backlight panel that illuminates the display panel.

Claims

1. A method comprising:

enabling an environment to be viewed through a display device;

generating light with a light source;

refracting the light with light refraction features spaced for a percentage of transparency that permits the environment behind the display device to be viewed through the display device;

illuminating the display device with the refracted light; and

switching on an active diffuser to prevent a section of the environment from being viewed through the display device

wherein the light refraction features comprise light-scattering particles embedded in a backlight panel of the display device, the light-scattering particles refracting designated light wavelengths.

2. The method as recited in claim 1, further comprising switching off the active diffuser to enable the environment behind the display device to be viewed through the display device.

3. The method as recited in claim 1, wherein the light is refracted through a transparent display panel and the active diffuser is contained in an additional transparent panel of the display device.

4. The method as recited in claim 1, further comprising the active diffuser uniformly illuminating a display panel of the display device.

5. The method as recited in claim 1, wherein the light source comprises one or more arrays of light emitting diodes (LEDs), and the backlight panel is edge-lit by the one or more arrays of LEDs.

6. The method as recited in claim 1, wherein the light refraction features comprise micro extraction features formed as hemisphere divots into the backlight panel.

7. The method as recited in claim 1, wherein the light refraction features comprise negative prisms formed into the backlight panel, the negative prisms comprising nano-prisms configured to increase transparency.

8. A method, comprising:

generating light with a light source in a backlight assembly;

directing the light from the light source with a backlight panel to illuminate a display panel, the backlight panel and the display panel having light refraction features configured for a percentage of transparency that permits an environment to be viewed through the backlight assembly;

scattering the light from the light source with an active diffuser to prevent at least a section of the environment from being viewed through the backlight assembly; and

refracting designated wavelengths of the light with light-scattering particles embedded in the backlight panel.

9. The method as recited in claim 8, further comprising switching off the active diffuser to enable the environment to be viewed through the backlight assembly.

10. The method as recited in claim 8, wherein the light is refracted through the backlight panel and the display panel, and the active diffuser is contained in a transparent panel of the display device.

11. The method as recited in claim 8, further comprising the active diffuser uniformly illuminating the display panel of the backlight assembly.

12. The method as recited in claim 8, wherein the light source comprises one or more arrays of light emitting diodes (LEDs), and the backlight panel is edge-lit by the one or more arrays of LEDs.

13. The method as recited in claim 8, wherein the light-scattering particles are spaced for a percentage of transparency.

14. The method as recited in claim 8, further comprising refracting the light with micro extraction features formed as hemisphere divots into the backlight panel.

15. The method as recited in claim 8, further comprising refracting the light with negative prisms formed into the backlight panel, the negative prisms spaced for a percentage of transparency.

16. A transparent display assembly, comprising:

a light source configured to generate light;

light refraction features configured to refract the light and illuminate the transparent display assembly, the light refraction features spaced for a percentage of transparency that permits an environment behind the transparent display assembly to be viewed through the transparent display assembly; and

an active diffuser configured to switch on to prevent a section of the environment from being viewed through the transparent display assembly

wherein the light refraction features comprise light-scattering particles embedded in a backlight panel of the transparent display assembly, the light-scattering particles refracting designated light wavelengths.

17. The transparent display assembly as recited in claim 16, wherein the active diffuser is configured to switch off to enable the environment to be viewable through the transparent display assembly.

18. The transparent display assembly as recited in claim 16, wherein the light source comprises one or more arrays of light emitting diodes (LEDs), and the backlight panel of the transparent display assembly is edge-lit by the one or more arrays of LEDs.

19. The transparent display assembly as recited in claim 16, wherein the light refraction features further comprise at least one of:

micro extraction features formed as hemisphere divots into the backlight panel; and

negative prisms formed into the backlight panel, the negative prisms comprising nano-prisms configured to increase transparency.