METHOD, DEVICE AND SYSTEM FOR MULTI-COLOR SEQUENTIAL LCD PANEL

• US 20090135129A1
• Filed: 11/26/2008
• Published: 05/28/2009
• Est. Priority Date: 06/11/2001
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Ben-Chorin, Moshe, ROTH, Shmuel, Ben-David, Ilan
• Granted Patent: US 8,289,266 B2
• Time in Patent Office: Days
• US Class Current: 345/102
• 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 2310/0235 Field-sequential colour display
• CPC Class Codes: G09G 2310/065 Waveforms comprising zero voltage phase or pause
• CPC Class Codes: G09G 2320/0242 Compensation of deficiencies in the appearance of colours
• CPC Class Codes: G09G 2320/0285 using tables for spatial correction of display data
• CPC Class Codes: G09G 3/2003 Display of colours specific for liquid crystal displays G09G3/3607
• CPC Class Codes: G09G 3/3413 Details of control of colour illumination sources
• CPC Class Codes: G09G 3/342 using several illumination sources separately controlled corresponding to different display panel areas, e.g. along one dimension such as lines
• CPC Class Codes: G09G 3/3607 for displaying colours or for displaying grey scales with a specific pixel layout, e.g. using sub-pixels display of colours in flat matrix panels other than liquid crystal displays G09G3/2003; grey scales specific for television H04N3/127

Abstract

A sequential color LCD device for displaying a color image using at least four different primary colors, with back illumination system comprising of at least three color LEDs. The device is capable of activating at least two color LEDs simultaneously, thus obtaining additional display colors. A method is disclosed for displaying more than three colors using an LCD device having three color LEDs, in which the LED back illumination system sequentially illuminates the LC array with only a first single LED color, a simultaneous operation of first and second LED colors, and then only the second LED color. The device may drive the LC cells from a first color data value directly to a subsequent color data value directly, without driving the LC cell to zero transmittance prior to loading of the subsequent color data value. The device may correct for color phase shift and for the dependency of apparent color intensity.

Claims

1. A liquid crystal display (LCD) device comprising:

a controller operably connected to driving circuitry for a plurality of liquid crystal (LC) cells and further operably connected to an illumination control system for an array of light emitting diodes (LEDs) arranged behind said LC array and in alignment therewith, said array comprising at least three different LED colors, said controller to;

receive input image data, and based thereon to produce a plurality of color display frames, each said color display frame comprising color selection data for each of a plurality of display colors and color transmittance data corresponding to each said display color,

sequentially send the color transmittance data for said color display frames to said driving circuitry for controlling transmittance of said LC cells, and

sequentially send in synchronization with said color transmittance data said color selection data for said color display frames to said illumination control system for selectively activating said array of LEDs,

wherein for at least three of the display colors, the respective color selection data represents selective illumination of LEDs of a single color, and for at least one of the display colors, said color selection data represents selective illumination of LEDs of a plurality of colors, thereby sequentially producing color display frames representing more display colors than the number of LED colors.

2. The device according to claim 1, wherein said at least three different color LEDs comprise red, green, and blue LEDs.

3. The device according to claim 1, wherein said controller is to produce said plurality of color display frames by correcting for color phase shift between rows of said display.

4. The device according to claim 3, wherein said controller is to correct for color phase shift between rows of said display by modifying said color transmittance data based on a row number.

5. The device according to claim 1, wherein said controller is to produce said plurality of color display frames by driving said LC cells from a first transmittance value relating to a first display color directly to a subsequent transmittance value relating to a second display color directly.

6. The device according to claim 5, wherein said controller is further to produce said plurality of color display frames by correcting said subsequent transmittance value for a dependency of apparent color intensity relative to the first transmittance value.

7. A sequential LCD system comprising:

the controller of claim 1;

the driving circuitry connected to said controller and operably connected to drive the plurality of liquid crystal (LC) cells; and

the illumination control system connected to said controller and operably connected to selectively activate the array of light emitting diodes (LEDs).

8. The system of claim 7, further comprising

the array of LC cells;

and

the array of LEDs.

9. A method for controlling a Liquid Crystal Display (LCD) device, the method comprising:

receiving input image data;

based on said input image data, producing a plurality of color display frames, each said color display frame comprising color selection data for each of a plurality of display colors and color transmittance data corresponding to each said display color;

sequentially driving an array of LC cells based on color transmittance data, said sequence corresponding to said plurality of display colors;

sequentially activating in synchronization with said driving of the array of LC cells said array of LEDs, wherein for at least three of the display colors, the respective color selection data represents selective illumination of LEDs of a single color, and for at least one of the display colors, said color selection data represents selective illumination of LEDs of a plurality of colors, thereby sequentially producing color display frames representing more display colors than the number of LED colors.

10. The method according to claim 9, wherein said at least three different color LEDs comprise red, green, and blue LEDs.

11. The method according to claim 9, wherein producing said plurality of color display frames comprises correcting for color phase shift between rows of said display.

12. The method according to claim 11, wherein correcting for color phase shift between rows of said display comprises modifying said color transmittance data based on a row number.

13. The method according to claim 9, wherein producing said plurality of color display frames comprises driving said LC cells from a first transmittance value relating to a first display color directly to a subsequent transmittance value relating to a second display color directly.

14. The method according to claim 13, wherein producing said plurality of color display frames comprises correcting said subsequent transmittance value for a dependency of apparent color intensity relative to the first transmittance value.