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`111111 111111
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`1111111111111111111111111111111111111111111111111111111111111 1111111111111111111111111111111111111111111111111111111111111
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`USOOn02843B2 USOOn02843B2
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`(12) United States Patent (12) United States Patent
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`
`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
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`Apr. 10,2007 Apr. 10,2007
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`
`(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:
`
`
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`Jan. 8, 2004 Jan. 8, 2004
`
`(65)
`(65)
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`
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`Prior Publication Data Prior Publication Data
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`
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`US 2005/0104824 Al May 19, 2005 US 2005/0104824 Al May 19, 2005
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`
`
`(30) (30)
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`
`
`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
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`EP EP
`
`
`0539185 Al 0539185 Al
`
`0660297 A2 0660297 A2
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`0660297 A3 0660297 A3
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`1122711 A2 1122711 A2
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`1122711 A3 1122711 A3
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`
`4/1993 4/1993
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`6/1995 6/1995
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`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
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`to control a transmission rate of the liquid crystal device. to control a transmission rate of the liquid crystal device.
`
`
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`9 Claims, 10 Drawing Sheets 9 Claims, 10 Drawing Sheets
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`GN+2(2) GN+2(2)
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`SHARP EXHIBIT 1001
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`Page 1 of 15
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`u.s. Patent u.s. Patent
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`Sheet 1 of 10 Sheet 1 of 10
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`US 7,202,843 B2 US 7,202,843 B2
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`GN+2 GN+2
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`Fig. 1 Prior art Fig. 1 Prior art
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`Page 2 of 15
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`u.s. Patent u.s. Patent
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`Apr. 10,2007 Apr. 10,2007
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`Sheet 2 of 10 Sheet 2 of 10
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`US 7,202,843 B2 US 7,202,843 B2
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`Fig. 2 Prior art Fig. 2 Prior art
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`u.s. Patent u.s. Patent
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`Apr. 10,2007 Apr. 10,2007
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`Sheet 3 of 10 Sheet 3 of 10
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`US 7,202,843 B2 US 7,202,843 B2
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`I I
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`u.s. Patent u.s. Patent
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`Apr. 10,2007 Apr. 10,2007
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`Sheet 4 of 10 Sheet 4 of 10
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`US 7,202,843 B2 US 7,202,843 B2
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`1 - - -1 - - -
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`Sheet 5 of 10 Sheet 5 of 10
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`US 7,202,843 B2 US 7,202,843 B2
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`GN+I GN+J(2) GN+I GN+J(2)
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`Sheet 6 of 10 Sheet 6 of 10
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`US 7,202,843 B2 US 7,202,843 B2
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`f-----.------+-------,---+------r-----/--- Frame (doti bled) f-----.------+-------,---+------r-----/--- Frame (doti bled)
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`Fig. 6 Fig. 6
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`u.s. Patent u.s. Patent
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`Sheet 7 of 10 Sheet 7 of 10
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`US 7,202,843 B2 US 7,202,843 B2
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`Fig. 7 Fig. 7
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`u.s. Patent u.s. Patent
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`Sheet 8 of 10 Sheet 8 of 10
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`US 7,202,843 B2 US 7,202,843 B2
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`60 60
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`I I
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`L _ _ _ _ _ _ _ _ _ _ _ _ _ L _ _ _ _ _ _ _ _ _ _ _ _ _
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`_ _ _ _ _ _ _ _ J _ _ _ _ _ _ _ _ J
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`Fig. 8 Fig. 8
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`Page 9 of 15
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`u.s. Patent u.s. Patent
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`Apr. 10,2007 Apr. 10,2007
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`Sheet 9 of 10 Sheet 9 of 10
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`US 7,202,843 B2 US 7,202,843 B2
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`Gm+l Gm+l
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`Gm+2 Gm+2
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`1 1
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`G~ G~
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`Diff Diff
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`.£0 .£0
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`..... o ..... o
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`L--_--+ ____ --+-__ __ -+-______ Frame (original) L--_--+ ____ --+-__ __ -+-______ Frame (original)
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`N N
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`N+l N+l
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`Fig. 9 Fig. 9
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`Page 10 of 15
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`u.s. Patent u.s. Patent
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`Apr. 10,2007 Apr. 10,2007
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`Sheet 10 of 10 Sheet 10 of 10
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`US 7,202,843 B2 US 7,202,843 B2
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`Q.J Q.J
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`.2 .2
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`> >
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`(Ij (Ij
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`(Ij (Ij
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`-+-' -+-'
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`(Ij (Ij
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`"'0 "'0
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`....-....-
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`Q.J Q.J
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`x .-a.. x .-a..
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`GN+l GN+l
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`GN+U2) GN+U2)
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`GN GN(2) GN GN(2)
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`LG LG
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`[ [
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`Q.J Q.J
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`0 0
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`N N
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`N+l N+l
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`I I
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`I I
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`Frame (original) Frame (original)
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`Fig. 10 Fig. 10
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`Page 11 of 15
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`US 7,202,843 B2 US 7,202,843 B2
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`1 1
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`DRIVING CIRCUIT OF A LIQUID CRYSTAL DRIVING CIRCUIT OF A LIQUID CRYSTAL
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`DISPLAY PANEL AND RELATED DRIVING DISPLAY PANEL AND RELATED DRIVING
`METHOD
`METHOD
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`BACKGROUND OF INVENTION BACKGROUND OF INVENTION
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`1. Field of the Invention 1. Field of the Invention
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`The invention relates to a driving circuit of a liquid crystal The invention relates to a driving circuit of a liquid crystal
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`display (LCD) panel and its related driving method, and display (LCD) panel and its related driving method, and
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`more particularly, to a driving circuit for applying over two more particularly, to a driving circuit for applying over two
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`data impulses to a pixel electrode within one frame period, data impulses to a pixel electrode within one frame period,
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`and its related driving method. and its related driving method.
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`2. Description of the Prior Art 2. Description of the Prior Art
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`A liquid crystal display (LCD) has advantages of light(cid:173)A liquid crystal display (LCD) has advantages of light(cid:173)
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`weight, low power consumption, and low divergence and is 15 weight, low power consumption, and low divergence and is 15
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`applied to various portable equipment such as notebook applied to various portable equipment such as notebook
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`computers and personal digital assistants (PDAs). In addi(cid:173)computers and personal digital assistants (PDAs). In addi(cid:173)
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`tion, LCD monitors and LCD televisions are gaining in tion, LCD monitors and LCD televisions are gaining in
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`popularity as a substitute for traditional cathode ray tube popularity as a substitute for traditional cathode ray tube
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`(CRT) monitors and televisions. However, an LCD does 20 (CRT) monitors and televisions. However, an LCD does 20
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`have some disadvantages. Because of the limitations of have some disadvantages. Because of the limitations of
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`physical characteristics, the liquid crystal molecules need to physical characteristics, the liquid crystal molecules need to
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`be twisted and rearranged when changing input data, which be twisted and rearranged when changing input data, which
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`can cause the images to be delayed. For satisfying the rapid can cause the images to be delayed. For satisfying the rapid
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`switching requirements of multimedia equipment, improv- 25 switching requirements of multimedia equipment, improv- 25
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`ing the response speed of liquid crystal is desired. ing the response speed of liquid crystal is desired.
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`Generally when driving an LCD, a driving circuit receives Generally when driving an LCD, a driving circuit receives
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`a plurality of frame data and then generates corresponding a plurality of frame data and then generates corresponding
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`data impulses, scan voltages, and timing signals, according data impulses, scan voltages, and timing signals, according
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`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
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`LCD. Each of the frame data includes data for refreshing all LCD. Each of the frame data includes data for refreshing all
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`of the pixels within a frame period; thus each of the frame of the pixels within a frame period; thus each of the frame
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`data can be regarded as including a plurality of pixel data, data can be regarded as including a plurality of pixel data,
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`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
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`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
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`general standard, each pixel can switch among 256 (2 8general standard, each pixel can switch among 256 (2 8
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`) gray ) gray
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`levels, thus each of the pixel data is 8 bits in length. levels, thus each of the pixel data is 8 bits in length.
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`Please refer to FIG. 1 showing a timing diagram of pixel Please refer to FIG. 1 showing a timing diagram of pixel
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`data values varying in accordance with the frames. When data values varying in accordance with the frames. When
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`driving a pixel, the driving circuit receives a plurality of 40 driving a pixel, the driving circuit receives a plurality of 40
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`pixel data used for driving the pixel in sequence. As shown pixel data used for driving the pixel in sequence. As shown
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`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
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`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)
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`mines the gray level of the pixel in the frame periods N, mines the gray level of the pixel in the frame periods N,
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`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
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`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
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`data is, the larger the gray level is. The driving circuit data is, the larger the gray level is. The driving circuit
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`generates a data impulse corresponding to a frame period generates a data impulse corresponding to a frame period
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`according to the pixel data GN, GN+l, GN+2, and applies according to the pixel data GN, GN+l, GN+2, and applies
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`the pulse to a pixel electrode of the corresponding pixel to 50 the pulse to a pixel electrode of the corresponding pixel to 50
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`have the pixel be in the appropriate gray level as required have the pixel be in the appropriate gray level as required
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`within each frame period. within each frame period.
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`Please refer to FIG. 2 showing a timing diagram of Please refer to FIG. 2 showing a timing diagram of
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`different transmission rates of a pixel, varying in accordance different transmission rates of a pixel, varying in accordance
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`with the frames. Two curves C1, C2 are measured when the 55 with the frames. Two curves C1, C2 are measured when the 55
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`driving circuit changes the transmission rate from T1 to T2 driving circuit changes the transmission rate from T1 to T2
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`beginning at frame period N. The curve C1 shows the beginning at frame period N. The curve C1 shows the
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`transmission rate of a pixel not overdriven corresponding to transmission rate of a pixel not overdriven corresponding to
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`the frames, and the curve C2 shows the transmission rate of the frames, and the curve C2 shows the transmission rate of
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`the pixel overdriven corresponding to the frames. The u.s. 60 the pixel overdriven corresponding to the frames. The u.s. 60
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`published application No. 2002/0050965 is one of the ref(cid:173)published application No. 2002/0050965 is one of the ref(cid:173)
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`erences of the conventional overdriving method. There is a erences of the conventional overdriving method. There is a
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`time delay when charging liquid crystal molecules, so that time delay when charging liquid crystal molecules, so that
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`they cannot twist at a predetermined angle at a predeter(cid:173)they cannot twist at a predetermined angle at a predeter(cid:173)
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`mined transmission rate. As shown by the curve C1, in the 65 mined transmission rate. As shown by the curve C1, in the 65
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`case of not being overdriven, the transmission rate cannot case of not being overdriven, the transmission rate cannot
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`reach a predetermined level in the frame period N but has to reach a predetermined level in the frame period N but has to
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`2 2
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`wait nntil the frame period N+2. Such a delay causes wait nntil the frame period N+2. Such a delay causes
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`blurring. In order to improve that, some conventional LCD blurring. In order to improve that, some conventional LCD
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`are overdriven, which means applying a higher or a lower are overdriven, which means applying a higher or a lower
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`data impulse to the pixel electrode to accelerate the reaction data impulse to the pixel electrode to accelerate the reaction
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`speed of the liquid crystal molecules, so that the pixel can speed of the liquid crystal molecules, so that the pixel can
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`reach the predetermined gray level in a predetermined frame reach the predetermined gray level in a predetermined frame
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`period. As shown by the curve C2, in the case of being period. As shown by the curve C2, in the case of being
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`overdriven, although the reaction speed of the liquid crystal overdriven, although the reaction speed of the liquid crystal
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`molecules is faster than in case of not being overdriven, the molecules is faster than in case of not being overdriven, the
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`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
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`T2. Thus, the requirement of reaching T2 in the frame period T2. Thus, the requirement of reaching T2 in the frame period
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`N still remains unsatisfied. N still remains unsatisfied.
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`SUMMARY OF INVENTION
`SUMMARY OF INVENTION
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`It is therefore a primary objective of the claimed invention It is therefore a primary objective of the claimed invention
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`to provide a driving circuit of an LCD panel and its relating to provide a driving circuit of an LCD panel and its relating
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`driving method to solve the problem mentioned above. driving method to solve the problem mentioned above.
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`Briefly, the present invention provides a method for Briefly, the present invention provides a method for
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`driving an LCD panel. The LCD panel includes a plurality driving an LCD panel. The LCD panel includes a plurality
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`of scan lines, a plurality of data lines, and a plurality of of scan lines, a plurality of data lines, and a plurality of
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`pixels. Each pixel is connected to a corresponding scan line pixels. Each pixel is connected to a corresponding scan line
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`and a corresponding data line, and each pixel includes a and a corresponding data line, and each pixel includes a
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`liquid crystal device and a switching device connected to the liquid crystal device and a switching device connected to the
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`corresponding scan line, the corresponding data line, and the corresponding scan line, the corresponding data line, and the
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`liquid crystal device. The method includes receiving con(cid:173)liquid crystal device. The method includes receiving con(cid:173)
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`tinuously a plurality of frame data, generating a plurality of tinuously a plurality of frame data, generating a plurality of
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`data impulses for each pixel in every frame period according data impulses for each pixel in every frame period according
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`to the frame data and applying the data impulses to the liquid to the frame data and applying the data impulses to the liquid
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`crystal device of one of the pixels within one frame period crystal device of one of the pixels within one frame period
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`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
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`transmission rate of the liquid crystal device of the pixel. transmission rate of the liquid crystal device of the pixel.
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`The present invention further provides a driving circuit The present invention further provides a driving circuit
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`for driving an LCD panel including a blur clear converter for for driving an LCD panel including a blur clear converter for
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`receiving frame data every frame period, each frame data receiving frame data every frame period, each frame data
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`comprising a plurality of pixel data and each pixel data comprising a plurality of pixel data and each pixel data
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`corresponding to a pixel, the blur clear converter delaying corresponding to a pixel, the blur clear converter delaying
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`current frame data to generate delayed frame data and current frame data to generate delayed frame data and
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`generating a plurality of overdriven pixel data in every generating a plurality of overdriven pixel data in every
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`frame period for each pixel; a source driver for generating a frame period for each pixel; a source driver for generating a
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`plurality of data impulses to each pixel according to the plurality of data impulses to each pixel according to the
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`plurality of overdriven pixel data generated by the blur clear plurality of overdriven pixel data generated by the blur clear
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`converter and applying the data impulses to the liquid crystal converter and applying the data impulses to the liquid crystal
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`device of the pixel via the scan line connected to the pixel device of the pixel via the scan line connected to the pixel
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`in order to control the transmission rate of the liquid crystal in order to control the transmission rate of the liquid crystal
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`device; and a gate driver for applying a scan line voltage to device; and a gate driver for applying a scan line voltage to
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`the switch device of the pixel so that the data impulses can the switch device of the pixel so that the data impulses can
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`be applied to the liquid crystal device of the pixel. be applied to the liquid crystal device of the pixel.
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`These and other objectives of the present invention will These and other objectives of the present invention will
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`no doubt become obvious to those of ordinary skill in the art no doubt become obvious to those of ordinary skill in the art
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`after reading the following detailed description of the pre(cid:173)after reading the following detailed description of the pre(cid:173)
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`ferred embodiment that is illustrated in the various figures ferred embodiment that is illustrated in the various figures
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`and drawings. and drawings.
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`BRIEF DESCRIPTION OF DRAWINGS BRIEF DESCRIPTION OF DRAWINGS
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`FIG. 1 is a timing diagram of the pixel data values varying FIG. 1 is a timing diagram of the pixel data values varying
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`in accordance with the frames according to the prior art. in accordance with the frames according to the prior art.
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`FIG. 2 is a timing diagram of different transmission rates FIG. 2 is a timing diagram of different transmission rates
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`of the pixel varying in accordance with the frames. of the pixel varying in accordance with the frames.
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`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
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`panel according to the present invention. panel according to the present invention.
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`FIG. 4 is a circuit diagram of the LCD panel. FIG. 4 is a circuit diagram of the LCD panel.
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`FIG. 5 is a timing diagram of pixel data values varying in FIG. 5 is a timing diagram of pixel data values varying in
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`accordance with frames. accordance with frames.
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`FIG. 6 is a timing diagram of the transmission rate of the FIG. 6 is a timing diagram of the transmission rate of the
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`pixel varying in accordance with the frames. pixel varying in accordance with the frames.
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`Page 12 of 15
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`US 7,202,843 B2 US 7,202,843 B2
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`3 3
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`FIG. 7 is a block diagram of the blur clear converter FIG. 7 is a block diagram of the blur clear converter
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`according to the first embodiment of the present invention. according to the first embodiment of the present invention.
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`FIG. 8 is a block diagram of the blur clear converter FIG. 8 is a block diagram of the blur clear converter
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`according to the second embodiment of the present inven(cid:173)according to the second embodiment of the present inven(cid:173)
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`tion. tion.
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`FIG. 9 is a timing diagram of original pixel data received FIG. 9 is a timing diagram of original pixel data received
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`by the blur clear converter varying in accordance with the by the blur clear converter varying in accordance with the
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`frames. frames.
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`FIG. 10 is a timing diagram of overdriven pixel data FIG. 10 is a timing diagram of overdriven pixel data
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`generated by the blur clear converter varying in accordance generated by the blur clear converter varying in accordance
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`with the frames. with the frames.
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`DETAILED DESCRIPTION DETAILED DESCRIPTION
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`Please refer to FIG. 3 showing a block diagram of a Please refer to FIG. 3 showing a block diagram of a
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`driving circuit 10 and an LCD panel 30 according to the driving circuit 10 and an LCD panel 30 according to the
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`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
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`composite video signals Sc, which includes frame data and composite video signals Sc, which includes frame data and
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`timing data for driving the LCD panel 30, and processing the timing data for driving the LCD panel 30, and processing the
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`composite video signals Sc to separate them into frame composite video signals Sc to separate them into frame
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`signals G and control signals C. Subsequently, the blur clear signals G and control signals C. Subsequently, the blur clear
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`converter 14 continuously receives the control signals C and converter 14 continuously receives the control signals C and
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`the frame data included in the frame signals G and generates the frame data included in the frame signals G and generates
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`processed frame signals G including a plurality of over(cid:173)processed frame signals G including a plurality of over(cid:173)
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`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
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`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
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`corresponding data line voltages and scan line voltages
`corresponding data line voltages and scan line voltages
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`according to the plurality of overdriven data included in the according to the plurality of overdriven data included in the
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`frame signals G in order to drive the LCD panel 30 to frame signals G in order to drive the LCD panel 30 to
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`generate images corresponding to the composite video sig(cid:173)generate images corresponding to the composite video sig(cid:173)
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`nals Sc. nals Sc.
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`Please refer to FIG. 4 showing a circuit diagram of the Please refer to FIG. 4 showing a circuit diagram of the
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`LCD panel 30. The LCD panel 30 includes a plurality of LCD panel 30. The LCD panel 30 includes a plurality of
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`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
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`pixels 36. Each pixel 36 is connected to a corresponding pixels 36. Each pixel 36 is connected to a corresponding
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`scan line 32 and a corresponding data line 34, and each pixel scan line 32 and a corresponding data line 34, and each pixel
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`36 has a switching device 38 and a liquid crystal device 39 36 has a switching device 38 and a liquid crystal device 39
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`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)
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`nected to the corresponding scan line 32 and the correspond(cid:173)nected to the corresponding scan line 32 and the correspond(cid:173)
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`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
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`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
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`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
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`applied to the scan lines 32 to tum on the switching devices applied to the scan lines 32 to tum on the switching devices
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`38, and data voltages are applied to the data lines 34 and 38, and data voltages are applied to the data lines 34 and
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`transmitted to the pixel electrodes 30 thr