Liquid crystal display device

• US 7,623,202 B2
• Filed: 12/08/2004
• Issued: 11/24/2009
• Est. Priority Date: 12/11/2003
• Status: Active Grant

• Current Assignee: Japan Display Central Incorporated (Japan Display Incorporated)
• Original Assignee: Toshiba Matsushita Display Technology (Japan Display Incorporated)
• Inventors: Nishiyama, Kazuhiro, Araki, Shigesumi, Suzuki, Daiichi, Okita, Mitsutaka
• Primary Examiner(s): Font; Frank G
• Assistant Examiner(s): BLEVINS, JERRY M
• Application Number:
  US10/582,237
• Publication Number:
  US 20070164956A1
• Time in Patent Office: 1,812 Days
• Field of Search: 349/33, 349/96, 349106-109, 349/117, 349/123
• US Class Current: 349/106
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/1395 Optically compensated birefringence [OCB]- cells or PI- cells
• CPC Class Codes: G09G 2300/0491 Use of a bi-refringent liquid crystal, optically controlled bi-refringence [OCB] with bend and splay states, or electrically controlled bi-refringence [ECB] for controlling the color
• CPC Class Codes: G09G 2300/08 Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements
• CPC Class Codes: G09G 3/3614 Control of polarity reversal in general
• CPC Class Codes: G09G 3/3651 using multistable liquid crystals, e.g. ferroelectric liquid crystals

Abstract

It is possible to eliminate the blue tone in the black color display in the OCB liquid crystal display device. A liquid crystal display cell (110) includes an opposing substrate (130) having an opposing electrode (Ecom), an array substrate (120) having pixel electrodes of the respective colors (dpixR, dpixG, dpixB), a liquid crystal layer (140) arranged in a bend-arrangement and sandwiched between the opposing substrate (130) and the array substrate (120), and red, green, and blue filter layers (CF(R), CF(G), CF(B)) arranged on one of the substrates. The maximum voltage is applied when performing black color display on the display screen. At least the maximum voltage of the pixel electrode for blue color dpixB applied to the opposing electrode (Ecom) is made different from the maximum voltage of the pixel electrodes of the other colors applied to the opposing electrode (Ecom).

Claims

1. A liquid crystal display device comprising:

a liquid crystal display cell comprising;

an array substrate having a pixel electrode for each color of red, green, and blue arranged on the display screen in a matrix form,

an opposing substrate having an opposing electrode arranged in such a manner as to face the pixel electrodes of the array substrate,

an alignment layer formed on the pixel electrode and the opposing electrode,

a liquid crystal layer arranged in a bend alignment interposed between the array substrate and the opposing substrate, and

a filter comprising a red filter layer, a green filter layer, and a blue filter layer provided on one side of the substrates, the red filter layer being arranged corresponding to the red pixel electrode, the green filter layer being arranged corresponding to the green pixel electrode, and the blue filter layer being arranged corresponding to the blue pixel electrode;

a phase difference plate arranged on at least one of main surfaces of the liquid crystal display cell;

a pair of polarization plates arranged so as to interpose the liquid crystal display cell and the phase difference plate in the crossed-Nicol configuration; and

a voltage supplying source supplying the voltage applied to the blue pixel electrode in black display being different from the voltages applied to the red and green pixel electrodes in black display, and the voltage of the blue pixel electrode in black display being set to a voltage making the v′

value of the u′

v′

chromaticity diagram become the maximum.

2. The liquid crystal display device as described in claim 1, further comprising a backlight source arranged on one side of the polarization plate, having light emission peaks in light wavelength regions appropriate to the red, green, and blue filter layers respectively, and the blue wavelength region having light emission peaks at a longer wavelength side and a shorter wavelength side with reference to 450 nm.

3. The liquid crystal display device as described in claim 1, wherein the phase different plate comprises a hybrid phase difference plate and a double-axial phase difference plate.

4. The liquid crystal display device according to claim 1, wherein the voltage of the blue pixel electrode in the black display does not exceed 4.03V.

5. A liquid crystal display device comprising:

a liquid crystal display cell comprising;

an array substrate having a pixel electrode for each color of red, green, and blue arranged on the display screen in a matrix form,

an opposing substrate having an opposing electrode arranged in such a manner as to face the pixel electrodes of the array substrate,

an alignment layer formed on the pixel electrode and the opposing electrode,

a liquid crystal layer arranged in a bend alignment interposed between the array substrate and the opposing substrate, and

a filter comprising a red filter layer, a green filter layer, and a blue filter layer provided on one side of the substrates, the red filter layer being arranged corresponding to the red pixel electrode, the green filter layer being arranged corresponding to the green pixel electrode, and the blue filter layer being arranged corresponding to the blue pixel electrode;

a phase difference plate arranged on at least one of main surfaces of the liquid crystal display cell;

a pair of polarization plates arranged so as to interpose the liquid crystal display cell and the phase difference plate in the crossed-Nicol configuration; and

a voltage supplying source supplying the voltage applied to the blue pixel electrode in black display being different from the voltages applied to the red and green pixel electrodes in black display, and the maximum voltage of the blue pixel electrode being set to a voltage making the Z value of the XYZ stimulus value become the minimum.

6. The liquid crystal display device as described in claim 5, further comprising a backlight source arranged on one side of the polarization plate, having light emission peaks in light wavelength regions appropriate to the red, green, and blue filter layers respectively, and the blue wavelength region having light emission peaks at a longer wavelength side and a shorter wavelength side with reference to 450 nm.

7. The liquid crystal display device as described in claim 5, wherein the phase different plate comprises a hybrid phase difference plate and a double-axial phase difference plate.

8. The liquid crystal display device according to claim 5, wherein the voltage of the blue pixel electrode in the black display does not exceed 4.03V.

9. A liquid crystal display device comprising:

a liquid crystal display cell comprising;

an array substrate having a pixel electrode for each color of red, green, and blue arranged on the display screen in a matrix form,

an opposing substrate having an opposing electrode arranged in such a manner as to face the pixel electrodes of the array substrate,

an alignment layer formed on the pixel electrode and the opposing electrode,

a liquid crystal layer arranged in a bend alignment interposed between the array substrate and the opposing substrate, and

a filter comprising a red filter layer, a green filter layer, and a blue filter layer provided on one side of the substrates, the red filter layer being arranged corresponding to the red pixel electrode, the green filter layer being arranged corresponding to the green pixel electrode, and the blue filter layer being arranged corresponding to the blue pixel electrode;

a phase difference plate arranged on at least one of main surfaces of the liquid crystal display cell, the phase different plate comprising a hybrid phase difference plate;

a pair of polarization plates arranged so as to interpose the liquid crystal display cell and the phase difference plate in the crossed-Nicol configuration; and

a voltage supplying source supplying the voltage applied to the blue pixel electrode in black display being different from the voltages applied to the red and green pixel electrodes in black display, and the voltage of the blue pixel electrode in black display being set to a voltage making the v′

value of the u′

v′

chromaticity diagram become the maximum.

10. The liquid crystal display device according to claim 9, wherein the voltage of the blue pixel electrode in the black display does not exceed 4.03V.