`
`111111 111111
`
`
`1111111111111111111111111111111111111111111111111111111111111 1111111111111111111111111111111111111111111111111111111111111
`
`USOOn02843B2 USOOn02843B2
`
`(12) United States Patent (12) United States Patent
`
`
`Shen et al. Shen et al.
`
`
`(10) Patent No.: (10) Patent No.:
`
`(45) Date of Patent: (45) Date of Patent:
`
`
`US 7,202,843 B2 US 7,202,843 B2
`
`Apr. 10,2007 Apr. 10,2007
`
`
`(54) DRIVING CIRCUIT OF A LIQUID CRYSTAL (54) DRIVING CIRCUIT OF A LIQUID CRYSTAL
`
`DISPLAY PANEL AND RELATED DRIVING DISPLAY PANEL AND RELATED DRIVING
`
`METHOD METHOD
`
`
`
`(75) (75)
`
`
`Inventors: Yung-Hung Shen, Hsin-Chu (TW); Inventors: Yung-Hung Shen, Hsin-Chu (TW);
`
`Shih-Chung Wang, Kao-Hsiung (TW); Shih-Chung Wang, Kao-Hsiung (TW);
`
`Yuh-Ren Shen, Tai-Nan (TW); Yuh-Ren Shen, Tai-Nan (TW);
`
`Cheng-Jung Chen, Miao-Li Hsien Cheng-Jung Chen, Miao-Li Hsien
`
`(TW) (TW)
`
`
`(73) Assignee: Vastview Technology Inc., Hsin-Chu (73) Assignee: Vastview Technology Inc., Hsin-Chu
`
`(TW) (TW)
`
`
`
`( *) Notice: ( *) Notice:
`
`
`Subject to any disclaimer, the term of this Subject to any disclaimer, the term of this
`
`patent is extended or adjusted under 35 patent is extended or adjusted under 35
`
`U.S.c. 154(b) by 602 days. U.S.c. 154(b) by 602 days.
`
`
`
`(21) Appl. No.: 101707,741 (21) Appl. No.: 101707,741
`
`(22) Filed:
`(22) Filed:
`
`
`
`Jan. 8, 2004 Jan. 8, 2004
`
`(65)
`(65)
`
`
`
`Prior Publication Data Prior Publication Data
`
`
`
`US 2005/0104824 Al May 19, 2005 US 2005/0104824 Al May 19, 2005
`
`
`
`(30) (30)
`
`
`
`Foreign Application Priority Data Foreign Application Priority Data
`
`
`
`Nov. 17, 2003 Nov. 17, 2003
`
`
`
`(TW) (TW)
`
`
`
`.............................. 92132122 A .............................. 92132122 A
`
`(51) (51)
`
`
`
`
`Int. Cl. Int. Cl.
`
`(2006.01) (2006.01)
`
`G09G 3/36 G09G 3/36
`(52) U.S. Cl. ........................................... 345/87; 345/89
`(52) U.S. Cl. ........................................... 345/87; 345/89
`
`(58) Field of Classification Search ... ... ... ..... .... 345/87, (58) Field of Classification Search ... ... ... ..... .... 345/87,
`
`345/88,89,90,91,93,98,99,100,204, 345/88,89,90,91,93,98,99,100,204,
`
`345/589,596,600-605 345/589,596,600-605
`
`See application file for complete search history. See application file for complete search history.
`
`
`
`(56) (56)
`
`
`
`References Cited References Cited
`
`
`U.S. PATENT DOCUMENTS U.S. PATENT DOCUMENTS
`
`200110038372 Al * 111200 I Lee ............................. 345/89 200110038372 Al * 111200 I Lee ............................. 345/89
`
`
`4/2002 Jinda et al. 4/2002 Jinda et al.
`
`200210044115 Al 200210044115 Al
`
`3/2003 Takako et al. 3/2003 Takako et al.
`
`2003/0058264 Al 2003/0058264 Al
`
`2004/0119730 Al * 6/2004 Ham et al. .................. 345/692 2004/0119730 Al * 6/2004 Ham et al. .................. 345/692
`
`2004/0196229 Al * 1012004 Ham ........................... 345/87 2004/0196229 Al * 1012004 Ham ........................... 345/87
`
`2004/0246224 Al * 1212004 Tsai et al. ................... 345/100 2004/0246224 Al * 1212004 Tsai et al. ................... 345/100
`
`2005/0073630 Al * 4/2005 Chen et al. ................... 349/87 2005/0073630 Al * 4/2005 Chen et al. ................... 349/87
`
`
`
`FOREIGN PATENT DOCUMENTS FOREIGN PATENT DOCUMENTS
`
`
`EP EP
`
`EP EP
`
`EP EP
`
`EP EP
`
`EP EP
`
`
`0539185 Al 0539185 Al
`
`0660297 A2 0660297 A2
`
`0660297 A3 0660297 A3
`
`1122711 A2 1122711 A2
`
`1122711 A3 1122711 A3
`
`
`4/1993 4/1993
`
`6/1995 6/1995
`
`6/1995 6/1995
`8/2001
`8/2001
`8/2001
`8/2001
`
`
`
`OTHER PUBLICATIONS OTHER PUBLICATIONS
`
`
`Baek-Woon Lee, et al.; Reducing Gray-Level Response to One Baek-Woon Lee, et al.; Reducing Gray-Level Response to One
`Frame: Dynamic Capacitance compensation; Samsung Electronics
`Frame: Dynamic Capacitance compensation; Samsung Electronics
`Corp.; ISSNOOOI0966X, 2001.
`Corp.; ISSNOOOI0966X, 2001.
`
`* cited by examiner * cited by examiner
`
`Primary Examiner-Nitin Patel Primary Examiner-Nitin Patel
`
`(74) Attorney, Agent, or Firm-Winston Hsu (74) Attorney, Agent, or Firm-Winston Hsu
`
`
`
`(57) (57)
`
`
`
`ABSTRACT ABSTRACT
`
`
`A method for driving a liquid crystal display (LCD) panel A method for driving a liquid crystal display (LCD) panel
`
`includes receiving continuously a plurality of frame data, includes receiving continuously a plurality of frame data,
`
`generating a plurality of data impulses for each pixel every generating a plurality of data impulses for each pixel every
`
`frame period according to the frame data, and applying the frame period according to the frame data, and applying the
`
`data impulses to a liquid crystal device of a pixel within a data impulses to a liquid crystal device of a pixel within a
`
`frame period via the data line connected to the pixel in order frame period via the data line connected to the pixel in order
`
`to control a transmission rate of the liquid crystal device. to control a transmission rate of the liquid crystal device.
`
`
`
`9 Claims, 10 Drawing Sheets 9 Claims, 10 Drawing Sheets
`
`
`
`GN+2(2) GN+2(2)
`
`
`
`GN+2 GN+2
`
`
`
`GN+3 GN+3
`
`
`
`GN+3(2) GN+3(2)
`
`
`
`GN GN(2) GN GN(2)
`
`
`
`.. ..
`
`
`
`"'II . . . . . "'II . . . . .
`
`
`
`• •
`
`
`
`"'II . . . . . "'II . . . . .
`
`I n I n
`
`
`I I
`
`I I
`
`I n+1 I n+2 I n+3 I n+4 I n+5 I n+6 I I n+1 I n+2 I n+3 I n+4 I n+5 I n+6 I
`
`
`I I
`
`I I
`
`I I
`
`I I
`
`I I
`
`I I
`
`I I
`
`I I
`
`I I
`
`I I
`
`
`
`N-1 N-1
`
`
`
`N N
`
`
`
`Frame (doubled) Frame (doubled)
`
`
`
`Frame (originall Frame (originall
`
`SHARP EXHIBIT 1001
`
`Page 1 of 15
`
`
`
`
`
`u.s. Patent u.s. Patent
`
`
`
`Apr. 10,2007 Apr. 10,2007
`
`
`
`Sheet 1 of 10 Sheet 1 of 10
`
`
`
`US 7,202,843 B2 US 7,202,843 B2
`
`
`
`GN+2 GN+2
`
`
`.-0.... .-0....
`
`v x v x
`
`
`
`GN GN
`
`
`~------~------~--------+--------+---------Frame ~------~------~--------+--------+---------Frame
`
`N-l N-l
`
`N N
`
`
`
`Fig. 1 Prior art Fig. 1 Prior art
`
`Page 2 of 15
`
`
`
`
`
`u.s. Patent u.s. Patent
`
`
`
`Apr. 10,2007 Apr. 10,2007
`
`
`
`Sheet 2 of 10 Sheet 2 of 10
`
`
`
`US 7,202,843 B2 US 7,202,843 B2
`
`
`Q.! Q.!
`
`+-' +-'
`
`
`
`I I
`
`
`
`(2 (2
`
`
`
`I I
`
`
`
`1 1
`
`
`
`--
`
`
`
`--
`
`- -- -
`
`
`, . . . . , , . . . . ,
`
`
`
`1 1
`
`
`
`.. -.. ~.-.--.. -.. ~.-.--
`
`
`
`1 1
`
`
`
`1 1
`
`
`
`. " . "
`
`
`f f
`
`.,·····1 .,·····1
`
`
`
`1 1
`
`
`
`1 1
`
`
`
`I I
`
`
`
`1 1
`
`
`
`\ \
`
`
`
`(1 (1
`
`
`~ ..... T2 ~ ..... T2
`
`1 - - - - ---+- - - - - - -1 - -1 - - - - ---+- - - - - - -1 - -
`
`c c
`
`0 0
`
`rfj .-rfj .-
`
`rfj rfj
`
`E E
`
`rfj c rfj c
`
`~ ..... ~ .....
`
`E-E-
`
`I."" 1 I."" 1
`
`
`.·-···r .·-···r
`
`
`
`1 1
`
`
`
`. . ' . . '
`
`
`
`• •
`
`
`
`1 1
`
`
`
`1 1
`
`
`
`1 1
`
`
`
`1 1
`
`
`
`1 1
`
`
`
`1 1
`
`
`
`1 1
`
`
`
`1 1
`
`
`
`1 1
`
`
`T1~---~----+----~----~Frame T1~---~----+----~----~Frame
`
`N-1 N-1
`
`N N
`
`N+1 N+1
`
`
`
`Fig. 2 Prior art Fig. 2 Prior art
`
`Page 3 of 15
`
`
`
`
`
`u.s. Patent u.s. Patent
`
`
`
`Apr. 10,2007 Apr. 10,2007
`
`
`
`Sheet 3 of 10 Sheet 3 of 10
`
`
`
`US 7,202,843 B2 US 7,202,843 B2
`
`
`I I
`
`Sci Sci
`
`
`I I
`
`I I
`
`I I
`
`I I
`
`I I
`
`I I
`
`I I
`
`I I
`
`I I
`
`L -L -
`
`12 12
`
`
`
`
`
`- -( -- -( -
`
`
`Signal Signal
`
`controuer controuer
`
`
`
`14 14
`
`
`
`16 16
`
`- --f- - - - - - - f - - -- --f- - - - - - - f - - -
`
`
`--
`
`
`
`--
`
`
`--
`
`G _ G _
`
`
`
`C -C -
`
`
`Blur clear Blur clear
`
`converter converter
`
`
`
`G' G'
`
`
`
`C -C -
`
`Timing
`Timing
`
`controller controller
`
`
`
`l l
`
`
`18~ Source 18~ Source
`
`driver driver
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`Fig. 3 Fig. 3
`
`
`
`10 10
`
`
`20 I, 20 I,
`
`- --f-- --f-
`
`
`
`Gate driver Gate driver
`
`
`
`- - - t - -- - - t - -
`
`
`
`J J
`
`
`
`LCD panel LCD panel
`
`
`
`--
`
`
`- \ - \
`
`30 30
`
`
`
`--
`
`
`
`,-,-
`
`
`I I
`
`I I
`
`I I
`
`
`I I
`
`I I
`
`I I
`
`I I
`
`--I --I
`
`Page 4 of 15
`
`
`
`
`
`u.s. Patent u.s. Patent
`
`
`
`Apr. 10,2007 Apr. 10,2007
`
`
`
`Sheet 4 of 10 Sheet 4 of 10
`
`
`
`US 7,202,843 B2 US 7,202,843 B2
`
`
`
`1 - - -1 - - -
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`I I
`
`
`.. ..
`
`.. ..
`
`
`
`34 34
`
`
`
`34 34
`
`
`
`r -r -
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`- ~36 r - - - - - _~36 - ~36 r - - - - - _~36
`
`
`
`39 39
`
`
`
`39 39
`
`
`
`L _______ J L _______ J
`
`
`
`r-----~36 r-----~36
`
`
`
`L _______ J L _______ J
`
`
`
`r -r -
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`- _~36 - _~36
`
`
`
`3 3
`
`
`
`3 3
`
`
`
`~39 ~39
`
`
`
`39 39
`
`
`.. ..
`
`• •
`
`
`
`L __ _ L __ _
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`- ~ - ~
`
`
`
`Fig. 4 Fig. 4
`
`Page 5 of 15
`
`
`
`
`
`u.s. Patent u.s. Patent
`
`
`
`Apr. 10,2007 Apr. 10,2007
`
`
`
`Sheet 5 of 10 Sheet 5 of 10
`
`
`
`US 7,202,843 B2 US 7,202,843 B2
`
`
`
`GN+I GN+J(2) GN+I GN+J(2)
`
`
`
`GN+2(2) GN+2(2)
`
`
`
`GN+3 GN+3
`
`
`
`GN+2 GN+2
`
`
`
`GN+3(2) GN+3(2)
`
`
`
`GN GN(2) GN GN(2)
`
`
`
`......... .........
`
`I 0 I 0
`
`
`I I
`
`I I
`
`
`
`I I
`
`
`
`I I
`
`I n+1 : n+2 : 0+3 I n+4 : n+5 I n+6 I I n+1 : n+2 : 0+3 I n+4 : n+5 I n+6 I
`
`
`
`
`I I
`
`I I
`
`
`I I
`
`I I
`
`
`
`I I
`
`
`
`N-1 N-1
`
`
`
`N N
`
`
`
`Fig. 5 Fig. 5
`
`
`
`....... , ....... ,
`
`
`
`Frame (doubled) Frame (doubled)
`
`
`
`Frame (originall Frame (originall
`
`Page 6 of 15
`
`
`
`
`
`u.s. Patent u.s. Patent
`
`
`
`Apr. 10,2007 Apr. 10,2007
`
`
`
`Sheet 6 of 10 Sheet 6 of 10
`
`
`
`US 7,202,843 B2 US 7,202,843 B2
`
`
`
`f-----.------+-------,---+------r-----/--- Frame (doti bled) f-----.------+-------,---+------r-----/--- Frame (doti bled)
`
`
`
`" - - - - - - - - - - -+ - - - - - - -+ - - - - - -+ - - - - - - - - - - j - Frame (orig i naI) " - - - - - - - - - - -+ - - - - - - -+ - - - - - -+ - - - - - - - - - - j - Frame (orig i naI)
`
`
`
`Fig. 6 Fig. 6
`
`Page 7 of 15
`
`
`
`
`
`u.s. Patent u.s. Patent
`
`
`
`Apr. 10,2007 Apr. 10,2007
`
`
`
`Sheet 7 of 10 Sheet 7 of 10
`
`
`
`US 7,202,843 B2 US 7,202,843 B2
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`14 14
`
`j j
`
`
`
`- 1 - 1
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`
`--
`
`
`40 40
`
`I -----(--- -I -----(--- -
`
`11 Multiplier I 11 Multiplier I
`
`;---42 ;---42
`
`..J >1 Processing circuitl ..J >1 Processing circuitl
`
`
`
`Gm Gm
`
`
`
`Gm-1 Gm-1
`
`
`
`GN GN
`
`
`GN GN
`
`GN(2) GN(2)
`
`
`First image First image
`
`memory memory
`
`
`Second image Second image
`
`memory memory
`
`
`
`44/ 44/
`
`
`
`(2 (2
`
`
`
`--
`
`
`I I
`
`I I
`
`
`
`I I
`
`
`I I
`
`I I
`
`
`I I
`
`I I
`
`
`I I
`
`r---i-46 r---i-46
`
`
`I I
`
`I I
`
`I I
`
`
`I I
`
`I I
`
`
`
`I I
`
`
`I I
`
`I I
`
`
`I I
`
`I I
`
`
`I I
`
`I I
`
`
`I I
`
`I I
`
`I I
`
`
`
`I I
`
`
`\ \
`
`..J ..J
`
`
`
`\ \
`
`
`
`( (
`
`
`
`G G
`
`
`
`Sync Sync
`
`
`First memory First memory
`
`controller controller
`
`
`
`48/ 48/
`
`
`I I
`
`I I
`
`L _ _ _ _ _ _ _ _ _ _ _ _ L _ _ _ _ _ _ _ _ _ _ _ _
`
`
`I I
`
`I I
`
`Second memory f----+---50 Second memory f----+---50
`
`controller controller
`
`I I
`
`_______ J _______ J
`
`
`
`Fig. 7 Fig. 7
`
`Page 8 of 15
`
`
`
`
`
`u.s. Patent u.s. Patent
`
`
`
`Apr. 10,2007 Apr. 10,2007
`
`
`
`Sheet 8 of 10 Sheet 8 of 10
`
`
`
`US 7,202,843 B2 US 7,202,843 B2
`
`
`60 60
`
`62 62
`
`- - - - - - - - - C - - l - - - - - - - - - C - - l
`
`1----(---1----(---
`
`_C __ : _~~I Multiplier If-------,-----~-------,----------: _C_2~ _C __ : _~~I Multiplier If-------,-----~-------,----------: _C_2~
`
`
`
`Processing circuit Processing circuit
`
`
`
`64 64
`
`
`
`I I
`
`
`I I
`
`I I
`
`
`I I
`
`I I
`
`
`I I
`
`I I
`
`I I
`
`
`
`II II
`
`
`
`G G
`
`
`First image Gm First image Gm
`
`f-------'::~Second image Gm-l Third image ~70 f-------'::~Second image Gm-l Third image ~70
`
`memory memory
`
`memory memory
`
`memory memory
`
`
`
`Gm-l Gm-l
`
`
`
`Gm-l Gm-2 Gm-l Gm-2
`
`
`
`Gm-2 Gm-2
`
`
`7)4 7)4
`
`( (
`
`
`
`I I
`
`
`
`I 6\ I 6\
`
`
`I I
`
`I I
`
`I I
`
`I I
`
`I I
`
`I I
`
`I I
`
`I I
`
`I I
`
`
`"----------'\~~I Processing circU1tlf-+--~ G N-l "----------'\~~I Processing circU1tlf-+--~ G N-l
`
`7\ 7\
`
`
`: :
`GN-(2) GN-(2)
`
`
`
`I I
`
`
`I I
`
`I I
`
`
`I I
`
`"-------~clcomparing circuit ~ : "-------~clcomparing circuit ~ :
`
`I I
`
`L _ _ _ _ _ _ _ _ _ _ _ _ _ L _ _ _ _ _ _ _ _ _ _ _ _ _
`
`_ _ _ _ _ _ _ _ J _ _ _ _ _ _ _ _ J
`
`
`
`Fig. 8 Fig. 8
`
`Page 9 of 15
`
`
`
`
`
`u.s. Patent u.s. Patent
`
`
`
`Apr. 10,2007 Apr. 10,2007
`
`
`
`Sheet 9 of 10 Sheet 9 of 10
`
`
`
`US 7,202,843 B2 US 7,202,843 B2
`
`
`
`Gm+l Gm+l
`
`
`
`Gm+2 Gm+2
`
`
`1 1
`
`G~ G~
`
`
`
`Diff Diff
`
`
`.£0 .£0
`
`..... o ..... o
`
`
`L--_--+ ____ --+-__ __ -+-______ Frame (original) L--_--+ ____ --+-__ __ -+-______ Frame (original)
`
`N N
`
`N+l N+l
`
`
`
`Fig. 9 Fig. 9
`
`Page 10 of 15
`
`
`
`
`
`u.s. Patent u.s. Patent
`
`
`
`Apr. 10,2007 Apr. 10,2007
`
`
`
`Sheet 10 of 10 Sheet 10 of 10
`
`
`
`US 7,202,843 B2 US 7,202,843 B2
`
`
`
`Q.J Q.J
`
`
`.2 .2
`
`> >
`
`
`
`(Ij (Ij
`
`
`(Ij (Ij
`
`-+-' -+-'
`
`(Ij (Ij
`
`"'0 "'0
`
`....-....-
`
`Q.J Q.J
`
`
`
`x .-a.. x .-a..
`
`
`
`GN+l GN+l
`
`
`
`GN+U2) GN+U2)
`
`
`
`GN GN(2) GN GN(2)
`
`LG LG
`
`
`
`
`
`[ [
`
`
`"'0 "'0
`
`Q.J Q.J
`
`.2: .2:
`
`!-. !-.
`
`"'0 "'0
`
`!-. !-.
`
`Q.J > Q.J >
`
`0 0
`
`
`
`'" . .. '" . ..
`
`
`
`.. . .. .
`
`
`
`N N
`
`
`
`N+l N+l
`
`
`I I
`
`I I
`
`I I
`
`
`
`Frame (original) Frame (original)
`
`
`
`Fig. 10 Fig. 10
`
`Page 11 of 15
`
`
`
`
`
`US 7,202,843 B2 US 7,202,843 B2
`
`
`1 1
`
`DRIVING CIRCUIT OF A LIQUID CRYSTAL DRIVING CIRCUIT OF A LIQUID CRYSTAL
`
`DISPLAY PANEL AND RELATED DRIVING DISPLAY PANEL AND RELATED DRIVING
`METHOD
`METHOD
`
`
`
`BACKGROUND OF INVENTION BACKGROUND OF INVENTION
`
`
`1. Field of the Invention 1. Field of the Invention
`
`The invention relates to a driving circuit of a liquid crystal The invention relates to a driving circuit of a liquid crystal
`
`display (LCD) panel and its related driving method, and display (LCD) panel and its related driving method, and
`
`more particularly, to a driving circuit for applying over two more particularly, to a driving circuit for applying over two
`
`data impulses to a pixel electrode within one frame period, data impulses to a pixel electrode within one frame period,
`
`and its related driving method. and its related driving method.
`
`2. Description of the Prior Art 2. Description of the Prior Art
`
`A liquid crystal display (LCD) has advantages of light(cid:173)A liquid crystal display (LCD) has advantages of light(cid:173)
`
`weight, low power consumption, and low divergence and is 15 weight, low power consumption, and low divergence and is 15
`
`applied to various portable equipment such as notebook applied to various portable equipment such as notebook
`
`computers and personal digital assistants (PDAs). In addi(cid:173)computers and personal digital assistants (PDAs). In addi(cid:173)
`
`tion, LCD monitors and LCD televisions are gaining in tion, LCD monitors and LCD televisions are gaining in
`
`popularity as a substitute for traditional cathode ray tube popularity as a substitute for traditional cathode ray tube
`
`(CRT) monitors and televisions. However, an LCD does 20 (CRT) monitors and televisions. However, an LCD does 20
`
`have some disadvantages. Because of the limitations of have some disadvantages. Because of the limitations of
`
`physical characteristics, the liquid crystal molecules need to physical characteristics, the liquid crystal molecules need to
`
`be twisted and rearranged when changing input data, which be twisted and rearranged when changing input data, which
`
`can cause the images to be delayed. For satisfying the rapid can cause the images to be delayed. For satisfying the rapid
`
`switching requirements of multimedia equipment, improv- 25 switching requirements of multimedia equipment, improv- 25
`
`ing the response speed of liquid crystal is desired. ing the response speed of liquid crystal is desired.
`
`Generally when driving an LCD, a driving circuit receives Generally when driving an LCD, a driving circuit receives
`
`a plurality of frame data and then generates corresponding a plurality of frame data and then generates corresponding
`
`data impulses, scan voltages, and timing signals, according data impulses, scan voltages, and timing signals, according
`
`to the frame data, in order to control pixel operation of the 30 to the frame data, in order to control pixel operation of the 30
`
`LCD. Each of the frame data includes data for refreshing all LCD. Each of the frame data includes data for refreshing all
`
`of the pixels within a frame period; thus each of the frame of the pixels within a frame period; thus each of the frame
`
`data can be regarded as including a plurality of pixel data, data can be regarded as including a plurality of pixel data,
`
`and each of the pixel data is for defining the gray level that and each of the pixel data is for defining the gray level that
`
`a pixel is required to reach within a frame period. In the 35 a pixel is required to reach within a frame period. In the 35
`
`general standard, each pixel can switch among 256 (2 8general standard, each pixel can switch among 256 (2 8
`
`) gray ) gray
`
`levels, thus each of the pixel data is 8 bits in length. levels, thus each of the pixel data is 8 bits in length.
`
`Please refer to FIG. 1 showing a timing diagram of pixel Please refer to FIG. 1 showing a timing diagram of pixel
`
`data values varying in accordance with the frames. When data values varying in accordance with the frames. When
`
`driving a pixel, the driving circuit receives a plurality of 40 driving a pixel, the driving circuit receives a plurality of 40
`
`pixel data used for driving the pixel in sequence. As shown pixel data used for driving the pixel in sequence. As shown
`
`in FIG. 1, GN, GN+l, GN+2 are the pixel data received in in FIG. 1, GN, GN+l, GN+2 are the pixel data received in
`
`frame periods N, N+l, N+2, and the driving circuit deter(cid:173)frame periods N, N+l, N+2, and the driving circuit deter(cid:173)
`
`mines the gray level of the pixel in the frame periods N, mines the gray level of the pixel in the frame periods N,
`
`N+l, N+2 according to the values of the pixel data GN, 45 N+l, N+2 according to the values of the pixel data GN, 45
`
`GN+l, GN+2. In general, the larger the value of the pixel GN+l, GN+2. In general, the larger the value of the pixel
`
`data is, the larger the gray level is. The driving circuit data is, the larger the gray level is. The driving circuit
`
`generates a data impulse corresponding to a frame period generates a data impulse corresponding to a frame period
`
`according to the pixel data GN, GN+l, GN+2, and applies according to the pixel data GN, GN+l, GN+2, and applies
`
`the pulse to a pixel electrode of the corresponding pixel to 50 the pulse to a pixel electrode of the corresponding pixel to 50
`
`have the pixel be in the appropriate gray level as required have the pixel be in the appropriate gray level as required
`
`within each frame period. within each frame period.
`
`Please refer to FIG. 2 showing a timing diagram of Please refer to FIG. 2 showing a timing diagram of
`
`different transmission rates of a pixel, varying in accordance different transmission rates of a pixel, varying in accordance
`
`with the frames. Two curves C1, C2 are measured when the 55 with the frames. Two curves C1, C2 are measured when the 55
`
`driving circuit changes the transmission rate from T1 to T2 driving circuit changes the transmission rate from T1 to T2
`
`beginning at frame period N. The curve C1 shows the beginning at frame period N. The curve C1 shows the
`
`transmission rate of a pixel not overdriven corresponding to transmission rate of a pixel not overdriven corresponding to
`
`the frames, and the curve C2 shows the transmission rate of the frames, and the curve C2 shows the transmission rate of
`
`the pixel overdriven corresponding to the frames. The u.s. 60 the pixel overdriven corresponding to the frames. The u.s. 60
`
`published application No. 2002/0050965 is one of the ref(cid:173)published application No. 2002/0050965 is one of the ref(cid:173)
`
`erences of the conventional overdriving method. There is a erences of the conventional overdriving method. There is a
`
`time delay when charging liquid crystal molecules, so that time delay when charging liquid crystal molecules, so that
`
`they cannot twist at a predetermined angle at a predeter(cid:173)they cannot twist at a predetermined angle at a predeter(cid:173)
`
`mined transmission rate. As shown by the curve C1, in the 65 mined transmission rate. As shown by the curve C1, in the 65
`
`case of not being overdriven, the transmission rate cannot case of not being overdriven, the transmission rate cannot
`
`reach a predetermined level in the frame period N but has to reach a predetermined level in the frame period N but has to
`
`
`2 2
`
`wait nntil the frame period N+2. Such a delay causes wait nntil the frame period N+2. Such a delay causes
`
`blurring. In order to improve that, some conventional LCD blurring. In order to improve that, some conventional LCD
`
`are overdriven, which means applying a higher or a lower are overdriven, which means applying a higher or a lower
`
`data impulse to the pixel electrode to accelerate the reaction data impulse to the pixel electrode to accelerate the reaction
`
`speed of the liquid crystal molecules, so that the pixel can speed of the liquid crystal molecules, so that the pixel can
`
`reach the predetermined gray level in a predetermined frame reach the predetermined gray level in a predetermined frame
`
`period. As shown by the curve C2, in the case of being period. As shown by the curve C2, in the case of being
`
`overdriven, although the reaction speed of the liquid crystal overdriven, although the reaction speed of the liquid crystal
`
`molecules is faster than in case of not being overdriven, the molecules is faster than in case of not being overdriven, the
`
`10 transmission rate has to wait nntil frame period N + 1 to reach 10 transmission rate has to wait nntil frame period N + 1 to reach
`
`T2. Thus, the requirement of reaching T2 in the frame period T2. Thus, the requirement of reaching T2 in the frame period
`
`N still remains unsatisfied. N still remains unsatisfied.
`
`SUMMARY OF INVENTION
`SUMMARY OF INVENTION
`
`
`It is therefore a primary objective of the claimed invention It is therefore a primary objective of the claimed invention
`
`to provide a driving circuit of an LCD panel and its relating to provide a driving circuit of an LCD panel and its relating
`
`driving method to solve the problem mentioned above. driving method to solve the problem mentioned above.
`
`Briefly, the present invention provides a method for Briefly, the present invention provides a method for
`
`driving an LCD panel. The LCD panel includes a plurality driving an LCD panel. The LCD panel includes a plurality
`
`of scan lines, a plurality of data lines, and a plurality of of scan lines, a plurality of data lines, and a plurality of
`
`pixels. Each pixel is connected to a corresponding scan line pixels. Each pixel is connected to a corresponding scan line
`
`and a corresponding data line, and each pixel includes a and a corresponding data line, and each pixel includes a
`
`liquid crystal device and a switching device connected to the liquid crystal device and a switching device connected to the
`
`corresponding scan line, the corresponding data line, and the corresponding scan line, the corresponding data line, and the
`
`liquid crystal device. The method includes receiving con(cid:173)liquid crystal device. The method includes receiving con(cid:173)
`
`tinuously a plurality of frame data, generating a plurality of tinuously a plurality of frame data, generating a plurality of
`
`data impulses for each pixel in every frame period according data impulses for each pixel in every frame period according
`
`to the frame data and applying the data impulses to the liquid to the frame data and applying the data impulses to the liquid
`
`crystal device of one of the pixels within one frame period crystal device of one of the pixels within one frame period
`
`via the data line connected to the pixel in order to control the via the data line connected to the pixel in order to control the
`
`transmission rate of the liquid crystal device of the pixel. transmission rate of the liquid crystal device of the pixel.
`
`The present invention further provides a driving circuit The present invention further provides a driving circuit
`
`for driving an LCD panel including a blur clear converter for for driving an LCD panel including a blur clear converter for
`
`receiving frame data every frame period, each frame data receiving frame data every frame period, each frame data
`
`comprising a plurality of pixel data and each pixel data comprising a plurality of pixel data and each pixel data
`
`corresponding to a pixel, the blur clear converter delaying corresponding to a pixel, the blur clear converter delaying
`
`current frame data to generate delayed frame data and current frame data to generate delayed frame data and
`
`generating a plurality of overdriven pixel data in every generating a plurality of overdriven pixel data in every
`
`frame period for each pixel; a source driver for generating a frame period for each pixel; a source driver for generating a
`
`plurality of data impulses to each pixel according to the plurality of data impulses to each pixel according to the
`
`plurality of overdriven pixel data generated by the blur clear plurality of overdriven pixel data generated by the blur clear
`
`converter and applying the data impulses to the liquid crystal converter and applying the data impulses to the liquid crystal
`
`device of the pixel via the scan line connected to the pixel device of the pixel via the scan line connected to the pixel
`
`in order to control the transmission rate of the liquid crystal in order to control the transmission rate of the liquid crystal
`
`device; and a gate driver for applying a scan line voltage to device; and a gate driver for applying a scan line voltage to
`
`the switch device of the pixel so that the data impulses can the switch device of the pixel so that the data impulses can
`
`be applied to the liquid crystal device of the pixel. be applied to the liquid crystal device of the pixel.
`
`These and other objectives of the present invention will These and other objectives of the present invention will
`
`no doubt become obvious to those of ordinary skill in the art no doubt become obvious to those of ordinary skill in the art
`
`after reading the following detailed description of the pre(cid:173)after reading the following detailed description of the pre(cid:173)
`
`ferred embodiment that is illustrated in the various figures ferred embodiment that is illustrated in the various figures
`
`and drawings. and drawings.
`
`
`
`BRIEF DESCRIPTION OF DRAWINGS BRIEF DESCRIPTION OF DRAWINGS
`
`
`FIG. 1 is a timing diagram of the pixel data values varying FIG. 1 is a timing diagram of the pixel data values varying
`
`in accordance with the frames according to the prior art. in accordance with the frames according to the prior art.
`
`FIG. 2 is a timing diagram of different transmission rates FIG. 2 is a timing diagram of different transmission rates
`
`of the pixel varying in accordance with the frames. of the pixel varying in accordance with the frames.
`
`FIG. 3 is a block diagram of a driving circuit and an LCD FIG. 3 is a block diagram of a driving circuit and an LCD
`
`panel according to the present invention. panel according to the present invention.
`
`FIG. 4 is a circuit diagram of the LCD panel. FIG. 4 is a circuit diagram of the LCD panel.
`
`FIG. 5 is a timing diagram of pixel data values varying in FIG. 5 is a timing diagram of pixel data values varying in
`
`accordance with frames. accordance with frames.
`
`FIG. 6 is a timing diagram of the transmission rate of the FIG. 6 is a timing diagram of the transmission rate of the
`
`pixel varying in accordance with the frames. pixel varying in accordance with the frames.
`
`Page 12 of 15
`
`
`
`
`
`US 7,202,843 B2 US 7,202,843 B2
`
`
`3 3
`
`FIG. 7 is a block diagram of the blur clear converter FIG. 7 is a block diagram of the blur clear converter
`
`according to the first embodiment of the present invention. according to the first embodiment of the present invention.
`
`FIG. 8 is a block diagram of the blur clear converter FIG. 8 is a block diagram of the blur clear converter
`
`according to the second embodiment of the present inven(cid:173)according to the second embodiment of the present inven(cid:173)
`
`tion. tion.
`
`FIG. 9 is a timing diagram of original pixel data received FIG. 9 is a timing diagram of original pixel data received
`
`by the blur clear converter varying in accordance with the by the blur clear converter varying in accordance with the
`
`frames. frames.
`
`FIG. 10 is a timing diagram of overdriven pixel data FIG. 10 is a timing diagram of overdriven pixel data
`
`generated by the blur clear converter varying in accordance generated by the blur clear converter varying in accordance
`
`with the frames. with the frames.
`
`
`
`DETAILED DESCRIPTION DETAILED DESCRIPTION
`
`
`Please refer to FIG. 3 showing a block diagram of a Please refer to FIG. 3 showing a block diagram of a
`
`driving circuit 10 and an LCD panel 30 according to the driving circuit 10 and an LCD panel 30 according to the
`
`present invention. The driving circuit 10 is for driving the present invention. The driving circuit 10 is for driving the
`LCD panel 30, which includes a signal controller 12, a blur
`LCD panel 30, which includes a signal controller 12, a blur
`clear converter 14, a timing controller 16, a source driver 18,
`clear converter 14, a timing controller 16, a source driver 18,
`and a gate driver 20. The signal controller 12 is for receiving 20
`and a gate driver 20. The signal controller 12 is for receiving 20
`
`composite video signals Sc, which includes frame data and composite video signals Sc, which includes frame data and
`
`timing data for driving the LCD panel 30, and processing the timing data for driving the LCD panel 30, and processing the
`
`composite video signals Sc to separate them into frame composite video signals Sc to separate them into frame
`
`signals G and control signals C. Subsequently, the blur clear signals G and control signals C. Subsequently, the blur clear
`
`converter 14 continuously receives the control signals C and converter 14 continuously receives the control signals C and
`
`the frame data included in the frame signals G and generates the frame data included in the frame signals G and generates
`
`processed frame signals G including a plurality of over(cid:173)processed frame signals G including a plurality of over(cid:173)
`
`driven data according to the frame data. The timing con(cid:173)driven data according to the frame data. The timing con(cid:173)
`troller 16 controls the source driver 18 and the gate driver 20 troller 16 controls the source driver 18 and the gate driver 20
`
`
`according to the frame signals G and the control signals C according to the frame signals G and the control signals C
`so that the source driver 18 and the gate driver 20 generate so that the source driver 18 and the gate driver 20 generate
`
`corresponding data line voltages and scan line voltages
`corresponding data line voltages and scan line voltages
`
`according to the plurality of overdriven data included in the according to the plurality of overdriven data included in the
`
`frame signals G in order to drive the LCD panel 30 to frame signals G in order to drive the LCD panel 30 to
`
`generate images corresponding to the composite video sig(cid:173)generate images corresponding to the composite video sig(cid:173)
`
`nals Sc. nals Sc.
`
`Please refer to FIG. 4 showing a circuit diagram of the Please refer to FIG. 4 showing a circuit diagram of the
`
`LCD panel 30. The LCD panel 30 includes a plurality of LCD panel 30. The LCD panel 30 includes a plurality of
`
`scan lines 32, a plurality of data lines 34, and a plurality of scan lines 32, a plurality of data lines 34, and a plurality of
`
`pixels 36. Each pixel 36 is connected to a corresponding pixels 36. Each pixel 36 is connected to a corresponding
`
`scan line 32 and a corresponding data line 34, and each pixel scan line 32 and a corresponding data line 34, and each pixel
`
`36 has a switching device 38 and a liquid crystal device 39 36 has a switching device 38 and a liquid crystal device 39
`
`a.k.a. a pixel electrode. The switching device 38 is con(cid:173)a.k.a. a pixel electrode. The switching device 38 is con(cid:173)
`
`nected to the corresponding scan line 32 and the correspond(cid:173)nected to the corresponding scan line 32 and the correspond(cid:173)
`
`ing data line 34, and the source driver 18 and the gate driver ing data line 34, and the source driver 18 and the gate driver
`
`20 control the operation of each pixel 36 via the scan line 32 20 control the operation of each pixel 36 via the scan line 32
`
`and the data line 34. To drive the LCD 30, scan voltages are and the data line 34. To drive the LCD 30, scan voltages are
`
`applied to the scan lines 32 to tum on the switching devices applied to the scan lines 32 to tum on the switching devices
`
`38, and data voltages are applied to the data lines 34 and 38, and data voltages are applied to the data lines 34 and
`
`transmitted to the pixel electrodes 30 thr