Display apparatus and image forming apparatus

• US 7,375,735 B2
• Filed: 06/24/2005
• Issued: 05/20/2008
• Est. Priority Date: 05/06/2004
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.), Qualcomm, Inc.
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Asao, Yasufumi
• Primary Examiner(s): PATEL, NITIN
• Application Number:
  US11/165,168
• Publication Number:
  US 20060017750A1
• Time in Patent Office: 1,061 Days
• Field of Search: 345 87-100, 345204-215, 345690-698, 349/12, 349 96-113, 348/488, 348/752
• US Class Current: 345/690
• 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 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 3/2051 with use of a spatial dither pattern
• CPC Class Codes: G09G 3/2074 using sub-pixels
• CPC Class Codes: G09G 3/344 based on particles moving in a fluid or in a gas, e.g. electrophoretic devices electrophoretic devices per se G02F1/167
• CPC Class Codes: G09G 3/3466 based on interferometric effect
• 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 display apparatus includes a display panel including a plurality of pixels exhibiting a brightness change range with respect to an applied voltage and a hue change range with respect to the applied voltage, and a control portion where a color image signal is inputted therein and a display signal is outputted to the display panel. The control portion includes a signal generator for generating and outputting a brightness display signal in the brightness change range, a hue display signal in the hue change range, and a signal for indicating a mixing ratio between the brightness display signal and the hue display signal, from the inputted color image signal. The display panel effects display, on the basis of the signal for indicating the mixing ratio, at a plurality of pixels in which pixels displaying in the brightness change range and pixels displaying in the hue change range are mixed.

Claims

1. A display apparatus, comprising:

a display panel comprising a plurality of pixels exhibiting a brightness change range with respect to an applied voltage and a hue change range with respect to the applied voltage, and

a control portion where a color image signal is inputted therein and a display signal is outputted to the display panel,

wherein the control portion comprises signal generation means for generating and outputting a brightness display signal in the brightness change range, a hue display signal in the hue change range, and a signal for indicating a mixing ratio between the brightness display signal and the hue display signal, from the inputted color image signal, and

wherein the display panel effects display, on the basis of the signal for indicating the mixing ratio, at a plurality of pixels in which pixels displaying in the brightness change range and pixels displaying in the hue change range are mixed.

2. A display apparatus according to claim 1, wherein the pixels exhibit a continuous brightness change range and a continuous hue change range with respect to the applied voltage, and wherein the signal generation means of the control portion is means for generating a continuous gradation display range in the brightness change range, a continuous gradation display signal in the hue change range, and a discrete signal for indicating a mixing ratio between these two signals, from the inputted color image signal.

3. A display apparatus according to claim 1, wherein the pixels exhibit a continuous brightness change range and a discontinuous hue change range with respect to the applied voltage, and wherein the signal generation means of the control portion is means for generating a continuous gradation display signal in the brightness change range, a discontinuous color display signal in the hue change range, and a discrete signal for indicating a mixing ratio between these two signals, from the inputted color image signal.

4. A display apparatus according to claim 1, wherein the pixels are provided with a color filter and exhibit a continuous brightness change range of a color of the color filter and a discontinuous hue change range with respect to the applied voltage, and wherein the signal generation means of the control portion outputs the continuous brightness display signal, a hue display signal at any value in the discontinuous hue change range, and a signal for indicating a mixing ratio between the brightness display signal and the hue display signal.

5. A display apparatus according to claim 1, wherein the pixels are provided with a color filter, a first subpixel exhibiting a continuous brightness change range of a color of the color filter and a discontinuous hue change range with respect to the applied voltage, a color filter of a color complementary to the color of the color filter at the first subpixel, and a second subpixel exhibiting a brightness change range of the color of the color filter with respect to the applied voltage, and

wherein the control portion outputs the brightness display signal, a hue display signal at any value in the discontinuous hue change range, and a signal for indicating a mixing ratio between the brightness display signal and the hue display signal to the first subpixel and outputs a brightness display signal for a color complementary to magenta to the second subpixel.

6. A display apparatus according to claim 5, wherein the color of the color filter at the first subpixel is magenta, and the hue change range of the first subpixel is a discontinuous hue change range including blue and red.

7. An image forming apparatus, comprising:

signal generation means for generating and outputting a brightness display signal in the brightness change range, a hue display signal in the hue change range, and a signal for indicating a mixing ratio between the brightness display signal and the hue display signal, from the inputted color image signal, and

means for forming a color image, on the basis of the signal for indicating the mixing ratio, by a plurality of pixels in which pixels displaying in the brightness change range and pixels displaying in the hue change range are mixed.