Bichromatic display

• US 7,705,855 B2
• Filed: 06/15/2006
• Issued: 04/27/2010
• Est. Priority Date: 06/15/2005
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Brown Elliott, Candice Hellen
• Primary Examiner(s): Wu; Xiao M
• Assistant Examiner(s): Ng; Lillian K
• Application Number:
  US11/424,539
• Publication Number:
  US 20060284872A1
• Time in Patent Office: 1,412 Days
• Field of Search: 345597-598, 345/603, 345/694, 345/88
• US Class Current: 345/589
• CPC Class Codes: G02F 2201/52 RGB geometrical arrangements
• CPC Class Codes: G09G 2300/0452 Details of colour pixel setup, e.g. pixel composed of a red, a blue and two green components
• CPC Class Codes: G09G 5/028 Circuits for converting colour display signals into monochrome display signals
• CPC Class Codes: H04N 1/56 Processing of colour picture signals H04N1/52 takes precedence

Abstract

A display system includes a subpixelated display panel having subpixels in two saturated primary colors. In one embodiment, the primary colors are selected so as to be a substantially metameric pair for an achromatic color such as white. Information display efficiencies arise from utilizing a checkerboard arrangement for the two primary colored subpixels and from using subpixel rendering algorithms to render an image on the display. The bichromatic display may display a black and white image combined with a monochromatic image, or may provide the capability to overlay a first image from a first image source carried on a chromatic channel onto a second image from a second image source carried on a luminance channel, where the first image source detects light wavelengths that the Human Vision System is not sensitive to, such as infrared light. This latter embodiment of the bichromatic display system is suitable for night vision devices.

Claims

1. A display system for displaying a multi-color image in response to receipt of input color image data, the display system comprising:

a spatial light modulator for displaying the multi-color image as its output;

the spatial light modulator having a display area populated by pixel units, wherein each pixel unit is essentially comprised of a subpixel repeating group, the subpixel repeating group having individually addressable subpixels among which there are just two non-white primary color emitters having dominant emission peaks at respective first and second primary color wavelengths;

the respective two primary colors emitted by the two primary color emitters defining respective primary color planes and also defining a substantially metameric pair of colors for white;

a gamut mapping function module which produces in response to the received input color image data, an intermediate image data set including first data representing brightness levels of sample points in the first primary color plane of the spatial light modulator and brightness levels of sample points in the second primary color plane of the spatial light modulator; and

a subpixel rendering module that performs area resampling operations on the intermediate image data set so as to produce resampled data points having implied positions corresponding to centers of spatial positionings in the spatial light modulator of the individually addressable subpixels.

2. The display system of claim 1 wherein the subpixel rendering module includes an area resampling filter structured to add to a weighted brightness contribution of a first sample point in one of the first and second primary color planes, weighted brightness contributions from neighboring sample points of the same-color plane.

3. The display system of claim 1 wherein:

the gamut mapping function module causes the intermediate image data set to further include second data representing a luminance plane defined by luminance points represented by the input color image data; and

the subpixel rendering module includes a Difference of Gaussians Wavelet filter structured to add to a weighted brightness contribution of a first sample point in one of the first and second primary color planes, weighted brightness contributions from neighboring sample points of the luminance plane.

4. The display system of claim 3 wherein:

the subpixel rendering module includes an area resampling filter structured to add to a weighted brightness contribution of a first sample point in one of the first and second primary color planes, weighted brightness contributions from neighboring sample points of the same-color plane; and

the subpixel rendering module uses a convolution of results from the area resampling filter and the Difference of Gaussians Wavelet filter.

5. The display system of claim 1 wherein the metameric pair of primary colors is selected from the group of pairs consisting of:

orange and bluish-cyan, green and magenta, yellow and blue, violet and yellow-green and pink and pastel-cyan.

6. The display system of claim 1 wherein the two primary colors have substantially a same effective luminance when perceived through the human visual system.

7. The display system of claim 1 wherein subpixels of the two primary colors are denoted as P₁ and P₂ and said two non-white primary color emitters are arranged in a checkerboard pattern in a four subpixel repeating group such that there are two P₁ emitters diagonally opposed to each other in the checkerboard pattern and two P₂ emitters diagonally opposed to each other.

8. The display system of claim 1 wherein the subpixel repeating group further includes an individually addressable white subpixel.

9. The display system of claim 8 wherein subpixels of the two non-white primary colors, P₁ and P₂, are arranged in a checkerboard pattern together with a plurality of individually addressable white (W) subpixels in accordance with a four subpixel repeating group where the two white (W) subpixels oppose each other diagonally and the two non-white primary colors, P₁ and P₂, oppose each other diagonally.

10. The display system of claim 8 wherein subpixels of the two non-white primary colors, P₁ and P₂, are arranged in a checkerboard pattern together with a plurality of individually addressable white (W) subpixels in accordance with an eight subpixel repeating group denoted as

11. The display system of claim 1 wherein the input color image data is comprised of data values specified as two primary colors different from all primary colors of the subpixel repeating group, where the primary colors of the subpixel repeating group include a white primary color.

12. The display system of claim 1 wherein the input color image data is comprised of first and second image source data;

the first image source data indicating achromatic image data, and the second image source data indicating monochromatic image data;

the display system producing an output image having the monochromatic image data overlaid over the achromatic image data.

13. The display system of claim 12 wherein the second image source data indicating monochromatic image data is a chromatic representation of infrared image data.

14. The display system of claim 1 wherein the spatial light modulator is a liquid crystal display panel.

15. A display system for processing and displaying infrared input image data in combination with a second input color image data comprising:

a first detector for detecting wavelengths of light in the infrared range from a scene to produce infrared input image data;

a second detector for detecting wavelengths of visible light from the scene to produce second input color image data;

an image combination module for combining the infrared input image data and the second input color image data into combined image data;

a spatial light modulator for displaying a multi-color image as its output;

the spatial light modulator having a display area populated by pixel units, wherein each pixel unit is essentially comprised of a subpixel repeating group, the subpixel repeating group having individually addressable subpixels among which there are just two non-white primary color emitters having dominant emission peaks at respective first and second primary color wavelengths;

the respective two primary colors emitted by the two primary color emitters defining respective primary color planes and also defining a substantially metameric pair of colors for white;

a gamut mapping function module which produces in response to the combined image data, an intermediate image data set including first data representing brightness levels of sample points in the first primary color plane of the spatial light modulator and brightness levels of sample points in the second primary color plane of the spatial light modulator; and

a subpixel rendering module that performs area resampling operations on the intermediate image data set so as to produce resampled data points having implied positions corresponding to centers of spatial positionings in the spatial light modulator of the individually addressable subpixels.

16. The display system of claim 15 wherein the infrared input image data is represented as chromatic image data and the second input color image data is represented as luminance data in the combined image data.

17. The display system of claim 15 wherein the metameric pair of primary colors is selected from the group of pairs consisting of:

orange and bluish-cyan, green and magenta, yellow and blue, violet and yellow-green and pink and pastel-cyan.

18. The display system of claim 15 wherein subpixels of the two primary colors, P₁ and P₂, are arranged to diagonally oppose one another in a checkerboard pattern.

19. The display system of claim 15 wherein the subpixel repeating group further includes a white subpixel.