Liquid crystal display device

• US 6,954,191 B1
• Filed: 11/10/2000
• Issued: 10/11/2005
• Est. Priority Date: 11/12/1999
• Status: Expired due to Fees

• Current Assignee: TPO Hong Kong Holding Limited (InnoLux Corporation)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Hirano, Satoshi, Yasui, Masaru, Hagino, Shuji, Kamiya, Takeo
• Primary Examiner(s): Chow, Dennis-Doon
• Assistant Examiner(s): Kumar, Srilakshmi K.
• Application Number:
  US09/889,088
• Time in Patent Office: 1,796 Days
• Field of Search: 345/77, 345 87- 89, 345/48, 345/63, 345/32, 345/600, 348/229.1, 382/279
• US Class Current: 345/77
• 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 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

This invention relates to an RGBW-typed LCD wherein a proper luminous image can be displayed according to a predetermined calculation with a decoder where some predetermined calculation formulas are embedded. Further, not only RGBW image display but also RGW image display can be used by a predetermined controlling signal.

Claims

1. A liquid crystal display apparatus capable of color-displaying comprising:

a crystal panel having, in each main pixel unit, a red outputting subpixel, a green outputting subpixel, a blue outputting subpixel, and a luminance-intensifying subpixel, and

a decoder that is configured to provide a digital value for driving the luminance-intensifying subpixel by carrying out a predetermined calculation processing using digital values respectively for a red inputting pixel, a green inputting pixel, and a blue inputting pixel which are obtained from an input image,

wherein;

the liquid crystal displaying apparatus driving the luminance-intensifying subpixel, the red outputting subpixel, the green outputting subpixel and the blue outputting subpixel by using the digital value for driving the luminance-intensifying subpixel obtained by the decoder and the digital values of the red, green and blue inputting subpixels, and

the predetermined calculation processing obtains the digital value for driving the luminance-intensifying subpixel by a function of W=f(Ymin, Ymax) where the digital value of the luminance-intensifying pixel is defined as W, and a minimum value and a maximum value of the digital values of the red inputting subpixel, the green inputting subpixel and the blue inputting subpixel are respectively defined as Ymin and Ymax, and the function f(Ymin, Ymax) provides an output value that is dependent upon both Ymin and Ymax.

2. A liquid crystal display apparatus according to claim 1, wherein the function of W=f(Ymin, Ymax) is directed to a function that monotonically increases as Ymin or Ymax increases.

3. A liquid crystal display apparatus according to claim 1, further including:

a memory that is configured to store a plurality of kinds of functions each represented by the function of W=f(Ymin, Ymax); and

a selector that is configured to select from among the plurality of kinds of functions represented by the function of W=f(Ymin, Ymax) stored by the memory.

4. A liquid crystal display apparatus according to claim 1, wherein the red outputting subpixel, the green outputting subpixel and the blue outputting subpixel are arranged to form a main pixel unit without using the luminance-intensifying subpixel in accordance with a predetermined control signal.

5. A liquid crystal display apparatus according to claim 1, wherein

the function W=f(Ymin, Ymax) is given as a function W=(Ymax*Ymin)/MAX², where MAX is a maximum value which digital values of the red inputting subpixel, the green inputting subpixel and the blue inputting subpixel can take.

6. A liquid crystal display apparatus according to claim 5, further including

a memory that is configured to store at least one other function for determining W, and

a selector that is configured to select among the functions for determining W stored by the memory.

7. A liquid crystal display apparatus according to claim 6, wherein

the at least one other function includes W=Max*{(Ymin+α

)/(MAX+β

)}ⁿ, where MAX is a maximum value which digital values of the red inputting subpixel, the green inputting subpixel and the blue inputting subpixel can take.

8. A liquid crystal display apparatus according to claim 6, wherein

the decoder is further configured to:

receive a control signal, and

selectively provide the digital value for driving the luminance-intensifying subpixel based on the control signal.

9. A liquid crystal display apparatus according to claim 5, wherein

the decoder is further configured to:

receive a control signal, and

selectively provide the digital value for driving the luminance-intensifying subpixel based on the control signal.

10. A liquid crystal display apparatus according to claim 1, wherein

the decoder is further configured to:

receive a control signal, and

selectively provide the digital value for driving the luminance-intensifying subpixel based on the control signal.

12. A liquid crystal display apparatus according to claim 1, further including

a memory that is configured to store at least one other function for determining W, and

a selector that is configured to select among the functions for determining W stored by the memory.

13. A liquid crystal display apparatus according to claim 12, wherein

the at least one other function includes W=Max*{(Ymin+α

)/(MAX+β

)}ⁿ, where MAX is a maximum value which digital values of the red inputting subpixel, the green inputting subpixel and the blue inputting subpixel can take.

11. A liquid crystal display apparatus capable of color-displaying comprising:

a crystal panel having, in each main pixel unit, a red outputting subpixel, a green outputting subpixel, a blue outputting subpixel, and a luminance-intensifying subpixel, and

a decoder that is configured to obtain a digital value for driving the luminance-intensifying subpixel by carrying out a predetermined calculation processing using digital values respectively for a red inputting pixel, a green inputting pixel, and a blue inputting pixel which are obtained from an input image,

wherein;

the liquid crystal displaying apparatus driving the luminance-intensifying subpixel, the red outputting subpixel, the green outputting subpixel and the blue outputting subpixel by using the digital value for driving the luminance-intensifying subpixel obtained by the decoder and the digital values of the red, green and blue inputting subpixels, and

the predetermined calculation processing by decoder provides the digital value for driving the luminance-intensifying subpixel by a function of W=f(Ymin, α

, β

, n) where the digital value of the luminance-intensifying pixel is defined as W, and a minimum value of the digital values of the red inputting subpixel, the green inputting subpixel and the blue inputting subpixel is defined as Ymin, and α

, β

, and n are predetermined real numbers, at least one of α and

β

being non-zero, and

a maximum value which digital values of the inputting subpixel, the green inputting subpixel and the blue inputting subpixel can take is defined as MAX, and the function of W=f(Ymin, α

, β

, n) is represented by a function of W=MaX*{(Ymin+α

)/(MAX+β

)}ⁿ.

14. A liquid crystal display apparatus according to claim 11, further including

a memory that is configured to store at least one other function for determining W, and

a selector that is configured to select among the functions for determining W stored by the memory.

15. A liquid crystal display apparatus according to claim 14, wherein

the at least one other function includes W=(Ymax*Ymin)/MAX².

16. A liquid crystal display apparatus according to claim 15, wherein

the decoder is further configured to:

receive a control signal, and

selectively provide the digital value for driving the luminance-intensifying subpixel based on the control signal.

17. A liquid crystal display apparatus according to claim 14, wherein

the decoder is further configured to:

receive a control signal, and

selectively provide the digital value for driving the luminance-intensifying subpixel based on the control signal.

18. A liquid crystal display apparatus according to claim 11, wherein

the decoder is further configured to:

receive a control signal, and

selectively provide the digital value for driving the luminance-intensifying subpixel based on the control signal.