Display unit and drive system thereof and an information display unit

• US 7,737,933 B2
• Filed: 09/26/2001
• Issued: 06/15/2010
• Est. Priority Date: 09/26/2000
• Status: Active Grant

• Current Assignee: Japan Display Central Incorporated (Japan Display Incorporated)
• Original Assignee: Toshiba Matsushita Display Technology (Japan Display Incorporated)
• Inventors: Yamano, Atsuhiro, Takahara, Hiroshi, Tsuge, Hitoshi
• Primary Examiner(s): Lefkowitz; Sumati
• Assistant Examiner(s): BODDIE, WILLIAM
• Application Number:
  US10/381,047
• Publication Number:
  US 20040066363A1
• Time in Patent Office: 3,184 Days
• Field of Search: 345/63, 345 94- 96, 345/98, 345/101, 345/206, 345/208, 345/210
• US Class Current: 345/94
• CPC Class Codes: G06F 3/14 Digital output to display device ; Cooperation and interconnection of the display device with other functional units
• CPC Class Codes: G09G 2310/0275 Details of drivers for data electrodes, other than drivers for liquid crystal, plasma or OLED displays, not related to handling digital grey scale data or to communication of data to the pixels by means of a current
• CPC Class Codes: G09G 2310/06 Details of flat display driving waveforms
• CPC Class Codes: G09G 2320/0209 Crosstalk reduction, i.e. to reduce direct or indirect influences of signals directed to a certain pixel of the displayed image on other pixels of said image, inclusive of influences affecting pixels in different frames or fields or sub-images which constitute a same image, e.g. left and right images of a stereoscopic display
• CPC Class Codes: G09G 2320/0247 Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes
• CPC Class Codes: G09G 2320/0276 for the purpose of adaptation to the characteristics of a display device, i.e. gamma correction
• CPC Class Codes: G09G 2320/041 Temperature compensation
• CPC Class Codes: G09G 2320/0606 Manual adjustment
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• CPC Class Codes: G09G 2320/0673 for control of gamma adjustment, e.g. selecting another gamma curve
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 2360/18 Use of a frame buffer in a display terminal, inclusive of the display panel
• CPC Class Codes: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
• CPC Class Codes: G09G 3/2018 by time modulation using two or more time intervals
• CPC Class Codes: G09G 3/2051 with use of a spatial dither pattern
• CPC Class Codes: G09G 3/32 semiconductive, e.g. using light-emitting diodes [LED]
• CPC Class Codes: G09G 3/3611 Control of matrices with row and column drivers
• CPC Class Codes: G09G 3/3625 using active addressing
• CPC Class Codes: G09G 3/3696 Generation of voltages supplied to electrode drivers
• CPC Class Codes: G09G 5/39 Control of the bit-mapped memory

Abstract

In a display panel, a dummy pulse of a predetermined voltage signal is superimposed on a data signal and the dummy pulse has an amplitude much larger than the amplitude of the data signal, and thus a signal waveform applied to a light modulation layer such as LC layer is changed to a high frequency wave. The applying position of the dummy pulse is varied according to each color of R, G and B, or varied according to frame or field. By performing a MLS drive with the dummy pulse superimposed on the data signal, the amplitude difference between the selection signal and the data signal can be reduced. Thus, a common driver IC and a segment driver IC can be formed as one semiconductor chip to be placed on one side, constructing a three side free type.

Claims

1. A matrix type display unit having multiple scanning electrodes and multiple signal electrodes, comprising:

a driver including a scanning circuit to drive said scanning electrodes and a signal circuit to drive said signal electrodes, said driver being positioned on one side of said display unit,

wherein a predetermined amplitude pulse, having an amplitude significantly greater than a data signal, is superimposed to one of the signal electrodes and one of the scanning electrodes simultaneously with one horizontal scanning period,

wherein the driver significantly reduces an amplitude of a selection signal and an amplitude difference between a selection signal and the data signal,

wherein the predetermined amplitude pulse is applied simultaneously at a predetermined pulse width to each of a plurality of scanning lines and each of a plurality of signal lines at an end of a subframe,

wherein a length of the subframe is (1+x)(N/4) or x+(N/4) pulse widths, wherein x is the predetermined pulse width, 0 <

×

<

1, N is a number of the scanning lines, N>

0, and a pulse width is a unit of time standardized to one scan pulse, and

wherein the driver simultaneously applies an amplitude of aV of drive voltage to each of the plurality of scanning lines, and the driver simultaneously applies an amplitude of 2V of drive voltage to each of the plurality of signal lines, wherein a is a bias ratio and V is a reference voltage.

2. The display unit according to claim 1, wherein the scanning circuit and the signal circuit are formed within a single semiconductor chip.

3. The display unit according to claim 1, wherein by selecting simultaneously L number of scanning electrodes where L is an integer greater than one, a gradation display is made.

9. An information display unit having the display unit according to claim 1 and an audio reception or transmission device.

10. The display unit according to claim 1, wherein the predetermined amplitude pulse is configured to be varied based on one or more of a plurality of parameters, the parameters comprising color, field, or frame.

4. A matrix type display unit having multiple scanning electrodes and multiple signal electrodes, comprising:

a predetermined amplitude pulse, having an amplitude significantly greater than a data signal, superimposed to one of the signal electrodes and one of the scanning electrodes simultaneously with one horizontal scanning period; and

a driver configured to significantly reduce an amplitude of a selection signal and an amplitude difference between a selection signal and the data signal,

wherein a width of said pulse is in a range from 0.06 to 0.23 when the horizontal scanning period is specified to be 1,

wherein the predetermined amplitude pulse is applied simultaneously at a predetermined pulse width to each of a plurality of scanning lines and each of a plurality of signal lines at an end of a subframe,

wherein a length of the subframe is (1+x)(N/4) or x+(N/4) pulse widths, wherein x is the predetermined pulse width, 0 <

×

<

1, N is a number of the scanning lines N>

0, and a pulse width is a unit of time standardized to one scan pulse, and

wherein the driver simultaneously applies an amplitude of aV of drive voltage to each of the plurality of scanning lines, and the driver simultaneously applies an amplitude of 2V of drive voltage to each of the plurality of signal lines, wherein a is a bias ratio and V is a reference voltage.

5. A matrix type display unit having multiple scanning electrodes and multiple signal electrodes, comprising:

a pulse applier for superimposing a predetermined amplitude pulse, having an amplitude significantly greater than a data signal, on one of the signal electrodes and one of the scanning electrodes simultaneously with one horizontal scanning period;

a pulse controller for changing at least one of a pulse width and a position of said one horizontal scanning period; and

a driver configured to significantly reduce an amplitude of a selection signal and an amplitude difference between a selection signal and the data signal,

wherein the predetermined amplitude pulse is applied simultaneously at a predetermined pulse width to each of a plurality of scanning lines and each of a plurality of signal lines at an end of a subframe,

wherein a length of the subframe is (1+x)(N/4) or x+(N/4) pulse widths, wherein x is the predetermined pulse width, 0>

×

>

1, N is a number of the scanning lines N>

0, and a pulse width is a unit of time standardized to one scan pulse, and

wherein the driver simultaneously applies an amplitude of aV of drive voltage to each of the plurality of scanning lines, and the driver simultaneously applies an amplitude of 2V of drive voltage to each of the plurality of signal lines, wherein a is a bias ratio and V is a reference voltage.

6. A driving method for a matrix type display unit having multiple scanning electrodes and multiple signal electrodes, comprising:

superimposing a predetermined amplitude pulse, having an amplitude significantly greater than a data signal, on one of the signal electrodes and one of the scanning electrodes simultaneously with one horizontal scanning period, wherein the pulse is continuously applied during horizontal scanning periods in odd-numbered and even-numbered order, and

significantly reducing an amplitude of a selection signal and an amplitude difference between a selection signal and the data signal,

wherein the predetermined amplitude pulse is applied simultaneously at a predetermined pulse width to each of a plurality of scanning lines and each of a plurality of signal lines at an end of a subframe,

wherein a length of the subframe is (1+x)(N/4) or x+(N/4) pulse widths, wherein x is the predetermined pulse width, 0<

×

<

1, N is a number of the scanning lines N>

0, and a pulse width is a unit of time standardized to one scan pulse, and

wherein the driver simultaneously applies an amplitude of aV of drive voltage to each of the plurality of scanning lines, and the driver simultaneously applies an amplitude of 2V of drive voltage to each of the plurality of signal lines, wherein a is a bias ratio and V is a reference voltage.

7. A driving method for a matrix type display unit having multiple scanning electrodes and multiple signal electrodes and having at least, a first pixel which modulates a first wavelength of light and a second pixel which modulates a second wavelength of light, said method comprising:

superimposing a predetermined amplitude pulse, having an amplitude significantly greater than a data signal, on one of the signal electrodes and one of the scanning electrodes simultaneously with one horizontal scanning period, wherein a starting position of a horizontal scanning period of a pulse applied to the first pixel is different from a starting position of a horizontal scanning period of a pulse applied to the second pixel, and

significantly reducing an amplitude of a selection signal and an amplitude difference between a selection signal and the data signal,

wherein the predetermined amplitude pulse is applied simultaneously at a predetermined pulse width to each of a plurality of scanning lines and each of a plurality of signal lines at an end of a subframe,

wherein a length of the subframe is (1+x)(N/4) or x+(N/4) pulse widths, wherein x is the predetermined pulse width, 0<

×

<

1, N is a number of the scanning lines N>

0, and a pulse width is a unit of time standardized to one scan pulse, and

wherein the driver simultaneously applies an amplitude of aV of drive voltage to each of the plurality of scanning lines, and the driver simultaneously applies an amplitude of 2V of drive voltage to each of the plurality of signal lines, wherein a is a bias ratio and V is a reference voltage.

8. A driving method for a matrix type display unit having multiple scanning electrodes and multiple signal electrodes, comprising:

superimposing a predetermined amplitude pulse, having an amplitude significantly greater than a data signal, on one of the signal electrodes and one of the scanning electrodes simultaneously with one horizontal scanning period, wherein by changing at least one of a pulse width and a pulse amplitude, a display brightness of the display unit is varied, and

significantly reducing an amplitude of a selection signal and an amplitude difference between a selection signal and the data signal, and

wherein the predetermined amplitude pulse is applied simultaneously at a predetermined pulse width to each of a plurality of scanning lines and each of a plurality of signal lines at an end of a subframe,

wherein a length of the subframe is (1+x)(N/4) or x+(N/4) pulse widths, wherein x is the predetermined pulse width, 0<

×

<

1, N is a number of the scanning lines N>

0, and a pulse width is a unit of time standardized to one pulse, and wherein the driver simultaneously applies an amplitude of aV of drive voltage to each of the plurality of scanning lines, and the driver simultaneously applies an amplitude of 2V of drive voltage to each of the plurality of signal lines, wherein a is a bias ratio and V is a reference voltage.