Backlighting in liquid crystal flat panel display
View Patent ↗Techniques for providing backlight techniques in liquid crystal flat panel displays are disclosed. According to one aspect of the techniques, the source to backlight a liquid crystal panel includes a plurality of light emitting diodes that are in at least three colors. The exact colors of the light emitting diodes are chosen to cover or exceed a full spectrum of color reproductions in accordance with a television standard (e.g., NTSC or PAL) in addition to a balanced white. In one embodiment, a set of control signals is configured to ensure that the light emitting diodes provide desired and consistent backlighting to a LCD panel. One of the control signals adaptive to a scene or content of a scene causes the backlighting to change accordingly or drastically to create artistic effects required or desired in the scene.
1. A liquid crystal display device comprising:
a liquid crystal display panel having a front viewing surface; and
a backlighting section placed in parallel behind the liquid crystal display panel,
wherein the backlighting section including:
a plurality of light emitting diodes in at least three color groups;
a controller controlling a power unit to energize the light emitting diodes in accordance with control signals;
a set of sensors sensing resultant lighting from the light emitting diodes, one of the control signals is fed back from the sensors such that the light emitting diodes provide consistent backlighting to the liquid crystal display panel.
2. The liquid crystal display device of claim 1 , wherein colors from the at least three color groups are additive.
3. The liquid crystal display device of claim 2 , wherein the light emitting diodes are generally in red, green and blue.
4. The liquid crystal display device of claim 1 , wherein the light emitting diodes are in four additive colors.
5. The liquid crystal display device of claim 4 , wherein the four additive colors are red, green 1, green 2 and blue, and wherein green 1 and green 2 are slightly different in wavelength such that a mixture of red, green 1, green 2 and blue in different weights reproduces substantially all colors in a spectrum defined by a standard.
6. The liquid crystal display device of claim 1 , wherein the light emitting diodes are formed by a number of color groups, each group including
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where N, M and K are integers, λ indicates a wavelength or a color.
7. The liquid crystal display device of claim 6 , wherein N, M and K are different integers to ensure that colors in a predefined visible spectrum can be substantially reproduced.
8. The liquid crystal display device of claim 7 , wherein the predefined visible spectrum is a superset of colors defined in accordance with a TV standard.
9. The liquid crystal display device of claim 1 , wherein one of the control signals is from a video processor configured to process video signals to be displayed on the liquid crystal display device, the one of the control signals causes the light emitting diodes to generate the backlighting in accordance with a scene in the video signals.
10. The liquid crystal display device of claim 9 , wherein the one of the control signals is selected from one of predefined levels in accordance with particular artistic effects to support the scene.
11. The liquid crystal display device of claim 1 , wherein at least one of the control signals is configured to control the light emitting diodes in at least three colors in accordance with a relative power ratio.
12. The liquid crystal display device of claim 1 , wherein at least one of the control signals is configured to control the light emitting diodes to generate a predetermined white color.
13. A liquid crystal display device comprising:
a liquid crystal display panel having a front viewing surface; and
a backlighting section placed in parallel behind the liquid crystal display panel,
wherein the backlighting section includes:
a plurality of light emitting diodes in at least four color groups;
a feedback loop including a controller controlling a power unit to energize the light emitting diodes in accordance with control signals, and a set of sensors sensing resultant lighting from the light emitting diodes;
wherein one of the control signals is fed back from the sensors such that the light emitting diodes provide consistent backlighting to the liquid crystal display panel;
wherein another one of the control signals is from a video processor configured to process video signals to be displayed on the liquid crystal display device, the another one of the control signals causes the light emitting diodes to generate the backlighting in accordance with a scene in the video signals so as to reach certain artistic effect according to the scene.
14. The liquid crystal display device of claim 13 , wherein the another one of the control signals is selected from one of predefined levels to boost or enhance the artistic effect to support the scene.
15. The liquid crystal display device of claim 14 , wherein the controller is configured to further receive at least a control signal configured to control the light emitting diodes in accordance with a relative power ratio.
16. The liquid crystal display device of claim 14 , wherein still another one of the control signals is from at least one sensor configured to sense sensation or purity of a color from one of the color groups.
17. The liquid crystal display device of claim 13 , wherein the light emitting diodes are formed by a number of color groups, each group including
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=
1
N
R
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λ
i
)
,
∑
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M
G
(
λ
i
)
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1
K
B
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λ
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)
,
where N, M and K are integers, λ indicates a wavelength or a color.
18. The liquid crystal display device of claim 17 , wherein N, M and K are different integers to ensure that colors in a predefined visible spectrum can be substantially reproduced.
19. The liquid crystal display device of claim 18 , wherein the predefined visible spectrum is a superset of colors defined in accordance with a TV standard.