US 7,095,397 B2 · Drive method, a drive circuit and a display device for liquid crystal cells

Abstract

A multiplex driving method is provided for a liquid crystal cell device having a liquid crystal layer disposed between a pair of substrates, a plurality of row electrodes arranged on one of the substrates and a plurality of column electrodes arranged on the other substrate. The method comprises the steps of sequentially selecting a group of the plurality of row electrodes during a selection period, simultaneously selecting the row electrodes comprising the group, and dividing and separating the selection period into a plurality of intervals within one frame period.

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Claims23

Dependent claims

A drive circuit for a display device having a plurality of scanning electrodes to which a selection signal and a non-selection signal are applied and a plurality of signal electrodes to which a data signal is applied, said drive circuit comprising:

scanning electrode drive means for
(1) grouping the plurality of scanning electrodes into p groups, wherein each of the p groups comprises at least i scanning electrodes, wherein p and i are integers of at least two,
(2) sequentially selecting each of the p groups and applying the selection signal substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N selection periods per frame, wherein N is an integer of at least two;
(3) sequentially applying the non-selection signal, immediately after applying the selection signal, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N non-selection periods per frame, a non-selection period being interposed between consecutive selection periods within each frame;
and
scanning data generation means for generating data representing a level of the selection signal;
wherein said scanning electrode drive means applies the selection signal, N times, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during the N selection periods per frame in accordance with the data generated by said scanning data generation means, at least one pulse wave among N pulse waves of the selection signal applied to each of the at least i scanning electrodes during the N selection periods being different from others of the N pulse waves during the N selection periods, and a pulse wave pattern of the N pulse waves of the selection signal applied to each of the at least i scanning electrodes in the selected one of the p groups during N selection periods is changed per frame;
memory means for storing display data;
arithmetic means for determining a data signal based on the data generated by said scanning data generation means and the display data stored in said memory means;
and
signal electrode drive means for applying a level of the data signal to the plurality of signal electrodes in accordance with said arithmetic means.

8 more elements

a scanning electrode driver to
(1) group the plurality of scanning electrodes into p groups, wherein each of the p groups comprises at least i scanning electrodes, wherein p and i are integers of at least two,
(2) sequentially select each of the p groups and apply the selection signal substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N selection periods per frame, wherein N is an integer of at least two;
(3) sequentially apply the non-selection signal, immediately after applying the selection signal, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N non-selection periods per frame, a non-selection period being interposed between consecutive selection periods within each frame;
and
a scanning data generator to generate data representing a level of the selection signal;
wherein said scanning electrode driver applies the selection signal, N times, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during the N selection periods per frame in accordance with the data generated by said scanning data generator, at least one pulse wave among N pulse waves of the selection signal applied to each of the at least i scanning electrodes during the N selection periods being different from others of the N pulse waves during the N selection periods, and a pulse wave pattern of the N pulse waves of the selection signal applied to each of the at least i scanning electrodes in the selected one of the p groups during N selection periods is changed per frame;
a memory to store display data;
an arithmetic operations unit to determine a data signal based on the data generated by said scanning data generator and the display data stored in said memory;
and
a signal electrode driver to apply a level of the data signal to the plurality of signal electrodes in accordance with said arithmetic operations unit.

8 more elements

A liquid crystal display apparatus comprising:

a liquid crystal matrix panel having a plurality of scanning electrodes to which a selection signal and a non-selection signal are applied and a plurality of signal electrodes to which a data signal is applied;
and
a driving circuit comprising:
scanning electrode drive means for
(1) grouping the plurality of scanning electrodes into p groups, wherein each of the p groups comprises at least i scanning electrodes, wherein p and i are integers of at least two,
(2) sequentially selecting each of the p groups and applying the selection signal substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N selection periods per frame, wherein N is an integer of at least two;
(3) sequentially applying the non-selection signal, immediately after applying the selection signal, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N non-selection periods per frame, a non-selection period being interposed between consecutive selection periods within each frame;
scanning data generation means for generating data representing a level of the selection signal,
wherein said scanning electrode drive means applies the selection signal, N times, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during the N selection periods per frame in accordance with the data generated by said scanning data generation means, at least one pulse wave among N pulse waves of the selection signal applied to each of the at least i scanning electrodes during the N selection periods being different from others of the N pulse waves during the N selection periods, and a pulse wave pattern of the N pulse waves of the selection signal applied to each of the at least i scanning electrodes in the selected one of the p groups during N selection periods is changed per frame;
memory means for storing display data;
arithmetic means for determining a data signal based on the data generated by said scanning data generation means and the display data stored in said memory means;
and
signal electrode drive means for applying a level of the data signal to the plurality of signal electrodes in accordance with said arithmetic means.

10 more elements

A liquid crystal display apparatus comprising:

a liquid crystal matrix panel having a plurality of scanning electrodes to which a selection signal and a non-selection signal are applied and a plurality of signal electrodes to which a data signal is applied;
and
a driving circuit comprising:
a scanning electrode driver to
(1) group the plurality of scanning electrodes into p groups, wherein each of the p groups comprises at least i scanning electrodes, wherein p and i are integers of at least two,
(2) sequentially select each of the p groups and apply the selection signal substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N selection periods per frame, wherein N is an integer of at least two;
(3) sequentially apply the non-selection signal, immediately after applying the selection signal, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N non-selection periods per frame, a non-selection period being interposed between consecutive selection periods within each frame;
a scanning data generator to generate data representing a level of the selection signal,
wherein said scanning electrode driver applies the selection signal, N times, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during the N selection periods per frame in accordance with the data generated by said scanning data generator, at least one pulse wave among N pulse waves of the selection signal applied to each of the at least i scanning electrodes during the N selection periods being different from others of the N pulse waves during the N selection periods, and a pulse wave pattern of the N pulse waves of the selection signal applied to each of the at least i scanning electrodes in the selected one of the p groups during N selection periods is changed per frame;
wherein said scanning electrode driver applies the level of the selection signal to the plurality of scanning electrodes in accordance with the data generated by said scanning data generator;
a memory to store display data;
an arithmetic operations unit to determine a data signal based on the data generated by said scanning data generator and the display data stored in said memory;
and
a signal electrode driver to apply a level of the data signal to the plurality of signal electrodes in accordance with said arithmetic operations unit.

11 more elements

A display apparatus comprising:

a display having a plurality of scanning electrodes and signal electrodes;
and
a drive circuit comprising:
scanning electrode drive means for
(1) grouping the plurality of scanning electrodes into p groups, wherein each of the p groups comprises at least i scanning electrodes, wherein p and i are integers of at least two,
(2) sequentially selecting each of the p groups and applying a selection signal substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N selection periods per frame, wherein N is an integer of at least two;
(3) sequentially applying a non-selection signal, immediately after applying the selection signal, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N non-selection periods per frame, a non-selection period being interposed between consecutive selection periods within each frame;
scanning data generation means for generating data representing a level of the selection signal,
wherein said scanning electrode drive means applies the selection signal, N times, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during the N selection periods per frame in accordance with the data generated by said scanning data generation means, at least one pulse wave among N pulse waves of the selection signal applied to each of the at least i scanning electrodes during the N selection periods being different from others of the N pulse waves during the N selection periods, and a pulse wave pattern of the N pulse waves of the selection signal applied to each of the at least i scanning electrodes in the selected one of the p groups during N selection periods is changed per frame;
memory means for storing display data;
arithmetic means for determining a data signal based on the data generated by said scanning data generation means and the display data stored in said memory means;
and
signal electrode drive means for applying a level of the data signal to the plurality of signal electrodes in accordance with said arithmetic means.

10 more elements

A display apparatus comprising:

a display having a plurality of scanning electrodes and signal electrodes;
and
a drive circuit comprising:
a scanning electrode driver to
(1) group the plurality of scanning electrodes into p groups, wherein each of the p groups comprises at least i scanning electrodes, wherein p and i are integers of at least two,
(2) sequentially select each of the p groups and apply a selection signal substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N selection periods per frame, wherein N is an integer of at least two;
(3) sequentially apply a non-selection signal, immediately after applying the selection signal, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N non-selection periods per frame, a non-selection period being interposed between consecutive selection periods within each frame;
a scanning data generator to generate data representing a level of the selection signal,
wherein said scanning electrode driver applies the selection signal, N times, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during the N selection periods per frame in accordance with the data generated by said scanning data generator, at least one pulse wave among N pulse waves of the selection signal applied to each of the at least i scanning electrodes during the N selection periods being different from others of the N pulse waves during the N selection periods, and a pulse wave pattern of the N pulse waves of the selection signal applied to each of the at least i scanning electrodes in the selected one of the p groups during N selection periods is changed per frame;
a memory to storing display data;
an arithmetic operations unit to determine a data signal based on the data generated by said scanning data generator and the display data stored in said memory;
and
a signal electrode driver to apply a level of the data signal to the plurality of signal electrodes in accordance with said arithmetic operations unit.

10 more elements

a scanning electrode driver that
(1) groups the plurality of scanning electrodes into p groups, wherein each of the p groups comprises at least i scanning electrodes, wherein p and i are integers of at least two,
(2) sequentially selects each of the p groups and applies the selection signal substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N selection periods per frame, wherein N is an integer of at least two;
(3) sequentially applies the non-selection signal, immediately after applying the selection signal, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N non-selection periods per frame, a non-selection period being interposed between consecutive selection periods within each frame;
a scanning data generator that generates data representing a level of the selection signal,
wherein said scanning electrode driver applies the selection signal, N times, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during the N selection periods per frame in accordance with the data generated by said scanning data generator, at least one pulse wave among N pulse waves of the selection signal applied to each of the at least i scanning electrodes during the N selection periods being different from others of the N pulse waves during the N selection periods, and a pulse wave pattern of the N pulse waves of the selection signal applied to each of the at least i scanning electrodes in the selected one of the p groups during N selection periods is changed per frame;
a memory that stores display data;
an arithmetic unit that determines a data signal based on the data generated by said scanning data generator and the display data stored in said memory;
and
a signal electrode driver that applies a level of the data signal to the plurality of signal electrodes in accordance with said arithmetic unit.

7 more elements

A liquid crystal display apparatus comprising:

a liquid crystal matrix panel having a plurality of scanning electrodes to which a selection signal and a non-selection signal are applied and a plurality of signal electrodes to which a data signal is applied;
and
a driving circuit comprising:
a scanning electrode driver that
(1) groups the plurality of scanning electrodes into p groups, wherein each of the p groups comprises at least i scanning electrodes, wherein p and i are integers of at least two,
(2) sequentially selects each of the p groups and applies the selection signal substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N selection periods per frame, wherein N is an integer of at least two;
(3) sequentially applies the non-selection signal, immediately after applying the selection signal, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N non-selection periods per frame, a non-selection period being interposed between consecutive selection periods within each frame;
a scanning data generator that generates data representing a level of the selection signal,
wherein said scanning electrode driver applies the selection signal, N times, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during the N selection periods per frame in accordance with the data generated by said scanning data generator, at least one pulse wave among N pulse waves of the selection signal applied to each of the at least i scanning electrodes during the N selection periods being different from others of the N pulse waves during the N selection periods, and a pulse wave pattern of the N pulse waves of the selection signal applied to each of the at least i scanning electrodes in the selected one of the p groups during N selection periods is changed per frame;
a memory that stores display data;
an arithmetic unit that determines a data signal based on the data generated by said scanning data generator and the display data stored in said memory;
and
a signal electrode driver that applies a level of the data signal to the plurality of signal electrodes in accordance with said arithmetic unit.

10 more elements

A display apparatus comprising:

a display having a plurality of scanning electrodes and signal electrodes;
and
a drive circuit comprising:
a scanning electrode driver that
(1) groups the plurality of scanning electrodes into p groups, wherein each of the p groups comprises at least i scanning electrodes, wherein p and i are integers of at least two,
(2) sequentially selects each of the p groups and applies a selection signal substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N selection periods per frame, wherein N is an integer of at least two;
(3) sequentially applies a non-selection signal, immediately after applying the selection signal, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N non-selection periods per frame, a non-selection period being interposed between consecutive selection periods within each frame;
a scanning data generator that generates data representing a level of the selection signal,
wherein said scanning electrode driver applies the selection signal, N times, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during the N selection periods per frame in accordance with the data generated by said scanning data generator, at least one pulse wave among N pulse waves of the selection signal applied to each of the at least i scanning electrodes during the N selection periods being different from others of the N pulse waves during the N selection periods, and a pulse wave pattern of the N pulse waves of the selection signal applied to each of the at least i scanning electrodes in the selected one of the p groups during N selection periods is changed per frame;
wherein said scanning electrode driver applies the level of the selection signal to the plurality of scanning electrodes in accordance with the data generated by said scanning data generator;
a memory that stores display data;
an arithmetic unit that determines a data signal based on the data generated by said scanning data generator and the display data stored in said memory;
and
a signal electrode driver that applies a level of the data signal to the plurality of signal electrodes in accordance with said arithmetic unit.

11 more elements

A display apparatus comprising:

a plurality of display elements disposed at intersections between a plurality of scanning electrodes to which a selection signal and non-selection signal are applied and a plurality of signal electrodes to which a data signal is applied;
and
a driving circuit comprising:
a scanning electrode driver that
(1) groups the plurality of scanning electrodes into p groups, wherein each of the p groups comprises at least i scanning electrodes and p and i are integers of at least two,
(2) sequentially selects each of the p groups and applies the selection signal substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N selection periods per frame, wherein N is an integer of at least two, the at least i scanning electrodes being a pattern,
(3) sequentially applies the non-selection signal, immediately after applying the selection signal, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N non-selection periods per frame, a non-selection period being interposed between consecutive selection periods within each frame,
wherein said scanning electrode driver applies the selection signal, N times, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during the N selection periods per frame in accordance with data generated by a scanning data generator, at least one pulse wave among N pulse waves of the selection signal applied to each of the at least i scanning electrodes during the N selection periods being different from others of the N pulse waves during the N selection periods, and a pulse wave pattern of the N pulse waves of the selection signal applied to each of the at least i scanning electrodes in the selected one of the p groups during N selection periods is changed per frame;
and
a signal electrode driver that applies a voltage level of the data signal to the plurality of signal electrodes, the voltage level of the data signal being determined in accordance with relationship between the predetermined pattern and the display data to be displayed at the display elements relative to the at least i scanning electrodes.

7 more elements

A display apparatus comprising:

a display having a plurality of scanning electrodes and a plurality of signal electrodes;
and
a driving circuit comprising:
a scanning electrode driver that
(1) groups the plurality of scanning electrodes into p groups, wherein each of the p groups comprises at least i scanning electrodes and p and i are integers of at least two,
(2) sequentially selects each of the p groups and applies a selection signal substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N selection periods per frame, wherein N is an integer of at least two, the at least i scanning electrodes being applied a voltage level of the scanning signal in accordance with predetermined pattern,
(3) sequentially applies a non-selection signal, immediately after applying the selection signal, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during each of N non-selection periods per frame, a non-selection period being interposed between consecutive selection periods within each frame,
wherein said scanning electrode driver applies the selection signal, N times, substantially simultaneously to the at least i scanning electrodes in the selected one of the p groups during the N selection periods per frame in accordance with data generated by a scanning data generator, at least one pulse wave among N pulse waves of the selection signal applied to each of the at least i scanning electrodes during the N selection periods being different from others of the N pulse waves during the N selection periods, and a pulse wave pattern of the N pulse waves of the selection signal applied to each of the at least i scanning electrodes in the selected one of the p groups during N selection periods is changed per frame;
and
a signal electrode driver that applies a voltage level of the data signal to the plurality of signal electrodes, the voltage level of the data signal being determined in accordance with relationship between the predetermined pattern and the display data to be displayed at display elements relative to the at least i scanning electrodes.

7 more elements

Dependencies are inferred from the claim text.

Description14,375 words

Summary5,995 words

#This application is also related to application Ser. No. 08/457,688, filed May 31, 1995, issued as U.S. Pat. No. 5,963,189, and application Ser. No. 09/277,585, filed Mar. 26, 1999, issued as U.S. Pat. No. 6,208,323.

#The present invention generally relates to a driving apparatus and a driving method for a liquid crystal display having a plurality of row electrodes and column electrodes. More particularly, the invention relates to such an apparatus and a method in which the row electrodes are divided into groups, each group being sequentially selected and the row electrodes within each group being simultaneously selected.

#Matrix liquid crystal displays such as, twisted nematic (TN) and super twisted nematic (STN), are known in the art. Reference is made to FIGS. 21(a)–(e) and 22 in which a conventional matrix liquid crystal display is provided. A liquid crystal panel generally indicated as 1 is composed of a liquid crystal layer 5, a first substrate 2 and a second substrate 3 for sandwiching the liquid crystal layer 5 therebetween. A group of column electrodes Y1–Ym are oriented on substrate 2 in the vertical direction and a plurality of row electrodes X1–Xn are formed on substrate 3 in substantially the horizontal direction to form a matrix. Each intersection of column electrodes Y1–Ym and row electrodes X1–Xn forms a display element or pixel 7. Display pixels 7 having the open circle indicate an ON state and those pixels having a blank indicate an OFF state.

Brief description of the drawings30 figures

#In the drawings, wherein like reference characters denote similar elements throughout the several views.

#FIGS. 1(a)–(d) show the applied voltage waveforms in accordance with the first embodiment of a driving method of the liquid crystal display according to the present invention.

#FIG. 2 shows a top view of a general configuration of the liquid crystal display.

Detailed description7,772 words

#Referring to FIGS. 4–6, a preferred example of a liquid crystal panel driving circuit according to the present invention is illustrated. More specifically, FIG. 4 illustrates a preferred drive circuit, FIG. 5 illustrates a preferred row electrode driver circuit and FIG. 6 illustrates a preferred column electrode driver circuit. Of course, while the circuits of FIGS. 4–6 are preferred, persons of ordinary skill in the art who have read this description will recognize that various modifications and changes may be made therein. The driving circuit is for driving a liquid crystal display panel 1, as shown in FIG. 22. In the preferred embodiment, the liquid crystal display panel comprises m column electrodes, Y1–Ym, and n row electrodes, X1–Xn. The intersections of the m column electrodes and n row electrodes form n×m pixels. In the preferred embodiment the n row electrodes are arranged in j groups of row electrodes, and each of the j groups of row electrodes comprise i row electrodes. In accordance with the invention, each of the j groups of row electrodes are selected sequentially, and each of the i row electrodes within each group are simultaneously selected. A detailed explanation of the driving method is presented hereinbelow.

#Turning to FIG. 4, reference numeral 1 denotes the row electrode driver and reference numeral number 2 represents the column electrode driver. Details of the row and column electrode driver circuits will be explained hereinbelow and are shown in FIGS. 5 and 6, respectively. Reference numeral 3 represents the frame memory, reference numeral 4 represents an arithmetic operations circuit; reference numeral 5 represents a row electrode data generation circuit; reference numeral 30 represents a clock circuit; reference numeral 6 represents a first latch and reference numeral 31 represents a second latch circuit.

#FIG. 5 illustrates a block diagram of the row electrode driver 1. In this drawing, reference numeral 11 is a first shift register; reference numeral 12 is a third latch circuit; reference numeral 13 is a first decoder circuit; reference numeral 14 is a first level shifter; and reference numeral 15 are first analog switches.

Facts

Application

10/164,984Filed 7 Jun 2002 · division

Priority

JP 4-487435 Mar 1992

Published

US 2003/0043099 A16 Mar 2003

Granted

22 Aug 2006

Term ended

6 Oct 2013

Estimated · how

20 years from earliest known nonprovisional domestic filing plus recorded patent term adjustment, including 216 days of adjustment. Maintenance-fee lapses, terminal disclaimers and statutory extensions have not been checked. The continuity chain may be incomplete; this is not an enforceability determination.

Classification9 codes

G09G 3/3681
Details of drivers for scan electrodes: suitable for passive matrices only
G09G 3/3622
Control of matrices with row and column drivers: using a passive matrix
G09G 3/3625
Using a passive matrix: using active addressing
G09G 3/2011
Display of intermediate tones: by amplitude modulation

Family

PCT/JP93/00279Parent of this continuation-in-part · filed 4 Mar 1993

Application08/148,083Parent of this continuation · filed 4 Nov 1993

Application09/281,997Parent of this division · filed 29 Mar 1999

Application09/821,063Parent of this division · filed 28 Mar 2001

US 2003/0043099 A1Pre-grant publication · published 6 Mar 2003

US 6,421,040 B2Parent of this division

US 6,252,573 B1Parent of this division

Application09/821,063Parent of this division

US 6,084,563 AParent of this continuation

Application09/281,997Parent of this continuation

Application08/148,083Parent of this continuation-in-part

US 2001/0030636 A1Published application

US 7,095,397 B2This patent

From the US filing history. Foreign family members aren’t listed.

Drive method, a drive circuit and a display device for liquid crystal cells

Life of this patent

Drive method, a drive circuit and a display device for liquid crystal cells

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims23

Description14,375 words

Drawings

Classification9 codes

Life of this patent

Description14,375 words