`Shimada et ai.
`
`111111
`
`1111111111111111111111111111111111111111111111111111111111111
`US006081250A
`[11] Patent Number:
`[45] Date of Patent:
`
`6,081,250
`Jun. 27,2000
`
`[54] ACTIVE MATRIX DISPLAY DEVICE AND
`ITS DRIVING METHOD
`
`[75]
`
`Inventors: Takayuki Shimada, Nara-ken;
`Toshihiro Yamashita; Yutaka
`Takafuji, both of Nara, all of Japan
`
`[73] Assignee: Sharp Kabushiki Kaisha, Osaka, Japan
`
`[21] Appl. No.: 08/266,159
`
`[22] Filed:
`
`Jun. 27, 1994
`
`Related U.S. Application Data
`
`[63] Continuation of application No. 08/009,115, Jan. 26, 1993,
`abandoned.
`
`[30]
`
`Foreign Application Priority Data
`
`Jan. 31, 1992
`
`[JP]
`
`Japan .................................... 4-016266
`
`Int. CI? ....................................................... G09G 3/36
`[51]
`[52] U.S. CI. ............................................... 345/94; 345/208
`[58] Field of Search ................................ 345/100, 89, 90,
`345/94, 95, 208, 99, 204, 87; 359/54
`
`[56]
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`4,724,433
`4,785,297
`4,842,371
`5,041,822
`
`2/1988 Inoue et al. ............................... 345/87
`11/1988 Sekiya ..................................... 340/784
`6/1989 Yasuda et al. .......................... 340/784
`8/1991 Hayashi .................................. 340/784
`
`5,253,091 10/1993 Kimura et al. ............................ 345/87
`
`FOREIGN PATENT DOCUMENTS
`
`0466378 A2
`3-163529
`3-163530
`3-163531
`2 146 478
`
`1/1992 European Pat. Off ..
`7/1991
`Japan.
`7/1991
`Japan.
`7/1991
`Japan.
`4/1985 United Kingdom.
`
`OTHER PUBLICATIONS
`
`Patent Abstracts of Japan, vol. 14, No. 580 (E-1017) Dec.
`25, 1990 & JP-A-02 252 378 (SONY) Oct. 11, 1990 (pp.
`501-507).
`Japan Display' 89, Emoto et al: 0.92 in. Active-Matrix LCD
`With Fully Integrated Poly-Si TFT Drivers of New Circuit
`Configuration, pp. 152-154.
`
`Primary Examiner-Regina Liang
`Attorney, Agent, or Firm-Nixon & Vanderhye, P.e.
`
`[57]
`
`ABSTRACT
`
`To enhance the display quality by improving the writing
`characteristic of active matrix display device.
`
`A plurality of signal lines of video signals are provided for
`pixels of each column arranged in two-dimensional array,
`and the driving element of each pixel is designed to be
`driven by anyone of the signal lines, so that the scanning
`time of each line may be extended longer than one horizontal
`scanning period.
`
`13 Claims, 8 Drawing Sheets
`
`f-<
`
`~
`U
`t:t:
`U
`Cl
`Z
`
`;>
`......
`~
`A
`W
`f-< <
`109 Cl
`
`SHARP EXHIBIT 1002
`
`Page 1 of 13
`
`
`
`u.s. Patent
`
`Jun. 27,2000
`
`Sheet 1 of 8
`
`6,081,250
`
`608
`
`Fi 9 . 1 (Prior Art)
`
`613
`
`SHIFT REGISTER
`
`612
`
`609
`
`U
`
`E-< -;::l
`p:: -u
`0 z -> -p::
`
`A
`
`~
`E-<
`<
`0
`
`603 606
`605
`604
`
`X1
`
`601
`
`X2
`
`X3
`
`XL.
`
`I
`
`I
`
`607
`
`I
`
`?,b.
`
`Page 2 of 13
`
`
`
`u.s. Patent
`
`Jun. 27,2000
`
`Sheet 2 of 8
`
`6,081,250
`
`Fig. 2 (Prior Art)
`
`~--------------1FIELD----------------~
`~1H
`
`Xl L
`
`X2+-----'
`
`X3 +----------'
`
`Xn~------------------------~
`
`Page 3 of 13
`
`
`
`u.s. Patent
`
`Jun. 27,2000
`
`Sheet 3 of 8
`
`6,081,250
`
`Fi g. 3 (Prior Art)
`
`-I
`I
`
`c1H
`
`ff
`
`f
`
`/--
`
`Xl J
`
`Xi~l
`
`Yl
`
`Y2
`
`ff
`Jf
`
`(
`I
`
`(
`I
`
`rL
`rL
`
`~-+4-------~~--~W~------~I~(---------
`
`tl
`
`Page 4 of 13
`
`
`
`u.s. Patent
`
`Jun. 27,2000
`
`Sheet 4 of 8
`
`6,081,250
`
`Fig.4
`
`108
`
`DRIVING CIRCUIT
`
`104
`
`f-4
`1-1
`::J
`U
`~
`1-1
`U
`0
`2
`
`1-1
`;>
`1-1
`~
`~
`
`~
`
`f-4 «
`109 0
`
`102a
`102b
`
`107b
`II,dI&
`107a
`
`Page 5 of 13
`
`
`
`u.s. Patent
`
`Jun. 27,2000
`
`Sheet 5 of 8
`
`6,081,250
`
`Fig. 5
`
`1 FIELD
`
`I .. 2H .. ~
`I
`f
`
`J
`
`l
`
`J
`
`I
`
`X1
`
`X2
`
`X3
`
`Xn
`
`fL
`}/
`
`-ff-
`
`--If
`
`-Ie.. J
`
`f
`
`Page 6 of 13
`
`
`
`u.s. Patent
`
`Jun. 27,2000
`
`Sheet 6 of 8
`
`6,081,250
`
`Fig. 6
`
`"I
`~I~----~/'~t----------r'----~ff~------~
`(1H
`J
`
`I
`
`j(
`]
`
`((
`)
`
`(I
`
`JL
`1/
`
`- /
`
`JJ
`
`fJl
`
`((
`.-
`
`Xi
`
`Xi+l
`
`Y1
`
`Y2
`
`Yl
`
`Ym
`
`Yrri
`
`II
`
`n
`
`' ( II
`
`if
`
`(I
`
`/ /
`JJ
`
`"
`II
`
`(f
`Jf
`
`ff-
`
`l· tl
`
`lt2
`
`Page 7 of 13
`
`
`
`u.s. Patent
`
`Jun. 27,2000
`
`Sheet 7 of 8
`
`6,081,250
`
`Fig. 7
`
`114a
`
`116
`
`103G
`
`~-f---t-\ 101
`
`102a
`114b
`103Sb
`115a
`105y
`102b ~ ~icr;::!=:;-J ~10==3D==10F5==X ~~
`
`Page 8 of 13
`
`
`
`Fig.8
`
`124
`
`d •
`rJl
`•
`~
`~ .....
`~ =
`.....
`
`~ = ?
`
`N
`~-..J
`N
`C
`C c
`
`105x
`
`(
`
`,
`
`.~(
`
`'JJ. =-
`105Y---F/< ( <;<,/~ <J<J<,~::\.'C_{_~~~_~.~~ ( (f<, ~/'</1105y ~
`~ .....
`00
`0 ....,
`A (\ "" ",~ "" .,~ ~ ''',~ ",~I.L.~SI~.IC~N FTlM. " '. " y. " "-
`\
`121
`
`00
`
`0\
`
`.... = 00
`Ul =
`
`~ ....
`N
`
`Page 9 of 13
`
`
`
`1
`ACTIVE MATRIX DISPLAY DEVICE AND
`ITS DRIVING METHOD
`
`6,081,250
`
`5
`
`This is a continuation of application Ser. No. 08/009,115,
`filed Jan. 26, 1993, now abandoned.
`BACKGROUND OF THE INVENTION
`1. Field of the Invention
`The present invention relates to an active matrix display
`device used in liquid crystal display device and the like, and
`its driving method.
`2. Description of the Related Art
`FIG. 1 shows an example of construction of active matrix
`liquid crystal display device having pixels of n rows and m
`columns in the prior art. A basic constitution of such prior art
`is disclosed, for example, in pages 152-154 of JAPAN
`DISPLAY '89. In the prior art shown in FIG. 1, additional
`capacitances are connected in parallel with the pixel
`(electrically equivalent to capacitance). In the drawing,
`numeral 603 is a switching element composed of a thin film
`transistor (hereinafter called TFT), which is turned on or off
`by a gate signal sent from a gate driving circuit 609 through
`a gate bus line 601. Numeral 608 denotes a source driving
`circuit, which is composed of analog switches 610 for
`sampling video signals sent from a video signal line 612 and 25
`writing into source bus line capacities 607, and a shift
`register 613 for sending the sampling control signal to gate
`electrode 611 of the analog switch.
`A video signal supplied to the source bus line 602 through
`the source driving circuit 608 is written into a pixel 606, 30
`which is equivalent to the capacitance being composed of a
`liquid crystal held between a pixel electrode disposed on
`each pixel and a counter electrode on a counter substrate,
`and into an additional capacitance 605 for compensating the
`capacitance of the pixel being connected in parallel with 35
`pixel 606 when the potential of the gate pulse line 601
`becomes high and the pixel TFT 603 is turned off.
`One terminal of this additional capacitance 605 is con(cid:173)
`nected to the pixel electrode, and the other is connected to
`a grounded additional capacitance line 604. The written 40
`signal is held in the OFF state of the TFT 603, but by
`installing the additional capacitance 605, the holding char(cid:173)
`acteristic of this signal may be improved, or the fluctuations
`of characteristics due to anisotropy of dielectric constant of
`the liquid crystal may be alleviated.
`FIG. 2 and FIG. 3 show examples of driving waveforms
`of conventional active matrix liquid crystal display device.
`FIG. 2 depicts signal waveforms delivered from the gate
`driving circuit 609 into individual gate bus lines Xl'
`- Xn during one field. The signal "H" corresponds to 50
`X2 -
`-
`the ON state of the pixel TFT 603, and "L" to the OFF state.
`- Xm
`Thus, in the sequence of the gate bus lines Xl' X2 -
`-
`the signal "H" is issued, and the pulse width of the output is
`nearly equal to the horizontal scanning time (known as
`"IH"). In this period of "IH", for on/off control of the 55
`analog switch 610 in the source driving circuit 608, control
`signals having the waveform as shown in FIG. 3 are applied
`to the gate electrode of each analog switch 610.
`The diagram shows the waveform when the i-th and
`i+l-th gate bus lines Xi' Xi+ l , are ON, as is similar in other 60
`cases. In this example, incidentally, the timing of change of
`the potential of the i-th gate bus line Xi from "H" to "L"
`coincides with the timing of change of the potential of the
`(i+l)-th gate bus line X i+ l from "L" to "H". In this period of
`IH, the m analog switches 610 are sequentially turned on, 65
`and the video signals are written into the source bus lines
`602.
`
`20
`
`15
`
`2
`A finite time tl must be provided from the moment of the
`previous stage gate bus line X i _ l becoming L until the first
`analog switch 610 is turned on by the control signal Y l' This
`is because the resistance of the gate bus line 601 is finite and
`the potential change is delayed. That is, if a video signal is
`written in the source bus line 602 by turning on the analog
`switch 610 by control signal Yl before the previous stage
`gate bus line X i_ l becomes sufficiently "L", since the
`resistance of the pixel TFT 603 connected to the previous
`is not sufficiently increased, the
`10 stage gate bus line X i_ l
`signal written in the previous stage pixel 606 may be
`disturbed by the video signal corresponding to the pixel 606
`of this stage.
`As a result, the display of the previous stage pixel is a
`mixture of the video signal for the previous stage and the
`video signal for the next stage, and the resolution is lowered.
`Therefore, the time tl should be set sufficiently long in order
`to decrease the effect of delay time of the gate bus line 601.
`Likewise, a finite time t2 must be provided from the moment
`of turning on the final analog switch 610 by control signal
`Y m until the potential of the gate bus line 601 is lowered to
`"L". This is because a finite time is required for writing
`signals into the pixel 606 and additional capacitance 605
`through the pixel TFT 603, and discharging the written
`charge through the additional capacitance wiring 604, and
`the video signal cannot be sufficiently written into the pixel
`606 unless a sufficiently long time is taken.
`It was thus a feature of the conventional active matrix
`liquid crystal display device that only one source bus line
`602 was connected to each pixel 606. In the driving method
`of the conventional active matrix display device, it was a
`feature that the ON time of each gate bus line 601 did not
`exceed the horizontal scanning time.
`In the conventional active matrix type liquid crystal
`display device, the greater the number of pixels, the higher
`becomes the resolution, and a favorable display quality may
`be obtained. However, as the number of pixels increases,
`several technical problems occur. For example, delays of the
`gate bus line and additional capacitance common line are
`noted. The line resistance and additional capacitance are
`both proportional to the number of pixels in the horizontal
`direction. Therefore, the time constant of delay of these lines
`is nearly proportional to the square of the number of pixels
`45 in the horizontal direction. Hence, as the number of pixels
`increases, the line delay increases noticeably. Accordingly,
`the times tl, t2 must be extended.
`In the display device having a great number of pixels,
`however, the horizontal scanning time becomes shorter. As
`a result, sufficiently long duration cannot be taken for times
`tl, t2 in order to decrease the effect of delay, which results
`in an increase of the effect of delay. When such effect of line
`delay increases, deterioration of display quality or the like
`may occur at one end of the screen. It is hitherto very
`difficult to improve the resolution without sacrificing the
`display quality. Besides, along with the increase of the
`number of pixels, the signal writing time for one pixel
`becomes shorter in proportion. Hence, it is also a problem
`that a faster writing speed of signal is required.
`The present inventors have previously disclosed some
`improved inventions in the Japanese Patent Publications No.
`163529/1991 and No. 163530/1991, with the purpose of
`reducing the effect of signal delay on display quality. In
`these inventions, by lowering the resistance of the additional
`capacitance line, the signal writing speed is enhanced.
`It is similarly an object of the present invention to reduce
`the effect of signal delay on display quality. In the invention,
`
`Page 10 of 13
`
`
`
`6,081,250
`
`4
`time t2 is from the moment when the video signal is read out
`to the final source bus line until the output of the gate bus
`line falls, and the time t3 is required to read out the video
`signal for pixel array if one row. In the conventional driving
`5 wave form, the sum is one horizontal time (lH). Therefore,
`the duration of tl, t2, t3 can be extended, and the effect of
`the line delay is lessened accordingly, so it is possible to
`present a display device, which is excellent in writing
`characteristics of the pixel transistor.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`15
`
`Other and further objects, features, and advantages of the
`invention will be more explicit from the following detailed
`description taken with reference to the drawings wherein:
`FIG. 1 is a structural diagram of a prior art.
`FIG. 2 is an operation explanatory diagram of FIG. 1.
`FIG. 3 is an operation explanatory diagram of FIG. 1.
`FIG. 4 is a structural diagram of an embodiment of the
`20 invention.
`FIG. 5 is an operation explanatory diagram of FIG. 4.
`FIG. 6 is an operation explanatory diagram of FIG. 4.
`FIG. 7 is a plan structural diagram showing a practical
`constitution of essential part of FIG. 4. and
`FIG. 8 is a sectional view from line A-A' of FIG. 7.
`
`25
`
`3
`however, this object is achieved by completely different
`means for substantially extending the writing time.
`To achieve the above object, the invention presents an
`active matrix display device comprising pixels in two(cid:173)
`dimensional arrangement, and having each pixel provided
`with a driving element for driving the pixel, wherein a
`plurality of signal lines for feeding signals to driving ele(cid:173)
`ments of pixels in each column are formed at each column,
`so that the successive rows of driving elements of the pixels
`in a column are connected to and successive ones driven by 10
`any the plurality of signal lines.
`In the invention, the pixel driving element of each row is
`arranged to be driven by a column signal from a signal line
`different from the driving element of the adjacent row.
`Also in the invention, the pixel driving element in each
`row comprises means for successively generating signals
`and for supplying the signals to the pixel driving element of
`each row to make active during the scanning time which is
`a product of one horizontal scanning time and a number of
`signal lines formed in each column.
`In the invention, the pixel driving elements are con(cid:173)
`structed as thin film transistors. In the invention, the signal
`provided for each column driving element is kept by capac(cid:173)
`ity of signal line for the moment.
`The invention also presents a driving method of an active
`matrix display device for driving a matrix display device,
`which is composed of pixels in two-dimensional
`arrangement, and driving elements disposed at each pixel for
`driving by means of selection signal for each row and video
`signal for each row wherein
`a plurality of signal lines for feeding signals to driving
`elements of pixels in each column are formed, and the
`successive rows of driving elements of pixels in a
`column are connected to and driven by successive ones 35
`of the plurality signal lines, so that the scanning time of
`the selection signal, when the driving element for
`driving pixels of each row is active, may be a product
`of one horizontal scanning time and a number of signal
`lines formed in each column.
`In the invention, the driving elements of pixels of each
`column are constructed so that the driving element of pixels
`of each adjacent row may be driven by a video signal from
`a different signal line.
`Also in the invention, the driving elements of pixels of 45
`each row are provided with a selection signal sequentially
`for making active only during the scanning time, while
`deviating the section signal by a predetermined time.
`In the invention, moreover, the driving elements of pixels
`of each row are provided with a video signal through one of 50
`the signal lines forming in a plurality at each column, after
`each row is made active by a selection signal and before the
`next row is made active by a selection signal.
`According to the above constitution, if ON signals are
`simultaneously sent to a plurality of adjacent gate bus lines, 55
`video signals to be written into adj acent pixels across gate
`bus lines will not be mixed mutually. Therefore, the output
`width of the ON signal sent out to each gate bus line may be
`set longer than the time assigned for one gate bus line. As a
`result, the time for decreasing the delay effect of signal line 60
`may be extended, and the effect of line delay may be
`decreased if the number of pixels is increased, so that the
`display quality may be enhanced.
`The invention is thus constructed so that the sum tl +t2+t3
`can be extended to 2H and so forth, where the time tl is from 65
`the moment when the gate bus line becomes high until
`reading of video signal to the first source bus line begins, the
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENT
`
`Now referring to the drawing, preferred embodiments of
`30 the invention are described below.
`FIG. 4 shows an example of circuit construction of an
`active matrix display device according to the invention. FIG.
`7 further shows an example of layout for TFT array part of
`this active matrix display device. Herein, numeral 101
`denotes a gate bus line, which is connected to a gate
`electrode 103G of a pixel TFT 103 composed of two TFTs
`connected in series. Numeral 109 is a gate driving circuit,
`which sends out an on/off signal for the pixel TFT 103 to the
`40 gate bus line 101.
`Numeral 108 is a source driving circuit, which is com(cid:173)
`posed of analog switches 110a, 110b interposed between a
`video signal line 112 and source bus lines 102a, 102b, and
`a driving circuit 113 for sending out the on/off control
`signals of the analog switches 110a, 110b to the gate
`electrodes of the analog switches 110a, 110b. The video
`signal is sent out to the source bus lines 102a, 102b through
`the source driving circuit 108 at adequate timing, written
`into capacitances 107a, 107b of the 107b of the source bus
`lines, and further written into a specific pixel through the
`pixel TFT 103 in ON state.
`The written video signal is written, in the OFF state of the
`pixel TFT 103, into a pixel 106 which is equivalent to a
`capacitance formed with a liquid crystal held between a
`pixel electrode 116 and a counter electrode and into an
`additional capacitance 105 connected in parallel with the
`pixel. One electrode 105x of the additional capacitance 105
`is connected to an additional capacitance common line 104,
`and is grounded. In one pixel array, a pair of source bus lines
`102a, 102b are disposed, which are connected alternately on
`every other row to source electrodes 103Sa, 103Sb of the
`pixel TFT 103 through contact holes 114a, 114b, respec(cid:173)
`tively as shown in FIG. 7.
`A drain electrode 103D of the pixel TFT 103 is connected
`to the other electrode 105y of the additional capacitance 105
`and to a pixel electrode 116 through contact holes 115a,
`115b as shown in FIG. 7.
`
`Page 11 of 13
`
`
`
`6,081,250
`
`15
`
`5
`A sectional structure along line A-A' of FIG. 7 is shown
`in FIG. 8. On a transparent insulating substrate 121, a
`polycrystalline silicon film 122 serving as a channel portion
`103c of the TFT 103 and the other electrode 105y of the
`additional capacitance 105, a gate insulation film 123, and a
`polycrystal line silicon film 124 doped with impurities
`serving as the gate electrode 103G of the TFT 103 and the
`one electrode 105x of the additional capacitance 105 are
`formed in this order. In specified part s of the polycrystalline
`silicon film, impurities are doped by ion implantation 10
`method. An insulating film 125 is formed in the upper part
`of the polycrystalline silicon film 124, and the contact hole
`115a is opened, and the pixel electrode 116 is formed by
`wiring such as source bus line of low resistance metal like
`as AI, and transparent conductive thin film like as ITO.
`FIG. 5 and FIG. 6 show driving waveforms in the embodi(cid:173)
`ment. FIG. 5 shows the signal waveform in one vertical
`scanning period (one field) sent out to gate bus lines Xl
`through Xn. When the potential to each gate bus lines Xl Xn
`becomes "H" level, the transistors the gate electrodes to 20
`which the gate bus lines Xl to Xn are connected, are turned
`on at the same time. In each gate bus line, the ON signal is
`sent out for the double duration of one horizontal scanning
`period (lH). The gate bus lines Xl to Xn send out signals at
`the timing shifted by the time of lH sequentially as shown 25
`in FIG. 5, and the output pulses of adjacent gate bus lines are
`overlapped by the duration of lH.
`FIG. 6 shows the detail about driving waveform in two
`horizontal scanning periods (2H). In the drawing, Xi and
`X i+ l are driving waveforms of the i-th and (i+l)-h gate bus 30
`lines respectively. Additionally Yl , Y'l' Y2, Y'2' to Y m, Y'm
`are gate signals to be fed into gate electrodes of the analog
`switches 110a, b respectively, and when the gate signal
`becomes "H", the corresponding analog switches 110a, bare
`turned on, and the video signal sent from the video signal 35
`line 112 is written into specific source bus lines 102a, b, and
`the video signal is further written into the specific pixel
`through the pixel TFT 103 in ON state.
`In this embodiment, first the gate bus line Xi becomes
`"H", and t1 time later the gate signal Y l' of the analog switch
`110a becomes "H", and the video signal is written in the
`corresponding source bus line, "H" is sent out on the
`previous stage gate bus line X i_ l . However, since the source
`bus line corresponding to the gate signal Y 1 is not connected
`to the TFT connected to the gate bus line X i_ l , a mixture of
`video signal does not occur because of the difference in the
`pulse width of the gate bus line.
`In the embodiment, by installing two source bus lines for
`one pixel column, the pulse width of each gate bus line is set 50
`twice as long as one horizontal scanning period for driving
`in the state free from mixture of video signals but the effect
`of the embodiment is not limited to this case alone, and when
`more source bus lines are provided, the output pulse width
`of the gate bus line may be set as many times as the number 55
`of source bus lines per pixel column in one horizontal
`scanning period.
`Further in the embodiment, the writing time of video
`signal may be extended. By once converting the incoming
`video signal into a digital signal, storing the digital signal 60
`into a memory and converting the stored signal into an
`analog signal again at specific timing, the writing time of the
`video signal for each pixel may be extended. As a result, the
`required characteristic of the analog switch may be
`alleviated, and the writing characteristic of the video signal 65
`is further enhanced, so that the display quality may be more
`improved.
`
`6
`The invention may be embodied in other specific forms
`without departing from the spirit or essential characteristics
`thereof. The present embodiments are therefore to be con(cid:173)
`sidered in all respects as illustrative and not restrictive, the
`5 scope of the invention being indicated by the appended
`claims rather than by the foregoing description and all
`changes which come within the meaning and the range of
`equivalency of the claims are therefore intended to be
`embraced therein.
`What is claimed is:
`1. An active matrix display device comprising:
`a plurality of pixels arranged two-dimensionally in col(cid:173)
`umns and rows,
`a plurality of driving elements wherein a driving element
`is provided for each pixel to drive the pixel, and
`wherein a group of signal lines for feeding signals to
`the driving elements are provided for each column of
`pixels and each driving element of a column is con-
`nected to a selected one of said group, so that the
`driving elements of each adjacent pixel in a column are
`driven by a different selected one of the signal lines
`from said group of signal lines and the driving elements
`provided for each row of pixels are connected to the
`same selected one in each group of signal lines pro(cid:173)
`vided for each column of pixels,
`a plurality of gating signal lines wherein each of the
`gating signal lines is connected to the driving elements
`of a single row of pixels so that each gating signal line
`provides an ON state gating signal to the driving
`elements of a different respective row of pixels, and
`wherein the time necessary to feed the signals from said
`group of signal lines for each column to each driving
`element of a row of pixels is substantially less than an
`ON state gating signal time of said row of pixels.
`2. An active matrix display device as in claim 1, further
`comprising means for successively generating and supply(cid:173)
`ing the ON state gating signals to the pixel driving elements
`of each row for successively driving each row for a time
`40 which is a product of the time necessary to feed the signals
`from said group of signal lines to each driving element of a
`row of pixels and the number of signal lines in said group for
`each column.
`3. An active matrix display device as in claim 1, wherein
`45 the pixel driving element is a thin film transistor.
`4. An active matrix display device as in claim 1, wherein
`the signal provided for each column driving element is
`temporarily capacitively stored by capacitor means for each
`signal line.
`5. An active matrix display device as in claim 1 wherein
`the time necessary to feed the signals from the group of
`signal lines for each column to the driving elements of a row
`of pixels is substantially one half the ON state gating signal
`time.
`6. An active matrix display device as in claim 1 wherein
`the device pixels are driven in a noninterlaced scanning
`mode.
`7. A driving method of an active matrix display device,
`which is composed of pixels in a two-dimensional arrange(cid:173)
`ment of columns and rows with a driving element disposed
`at each pixel, for driving by means of a selection signal for
`each row and video signals for each column, said method
`comprising:
`forming a plurality of signal lines in each column for
`feeding signals to the driving elements of pixels in each
`column, and driving the driving element of each pixel
`of a column by a selected one of the signal lines, so that
`
`Page 12 of 13
`
`
`
`6,081,250
`
`7
`the driving elements of each adjacent pixel in a column
`is driven by a different selected one of the plurality of
`signal lines,
`forming a plurality of row selection lines wherein each
`row selection line provides a row selection signal to a 5
`single row of driving elements and generating row
`selection signals so that the time that a row selection
`signal for each row of driving elements is active is
`substantially greater than the time necessary to provide
`said video signals for each column to the driving 10
`elements of a row and wherein the driving elements
`provided for each row of pixels are connected to the
`same selected one in each group of signal lines pro(cid:173)
`vided for each column of pixels.
`8. A driving method of an active matrix display device as 15
`in claim 7, further comprising: sequentially providing the
`driving elements of pixels of each row with an active row
`selection signal for sequentially making said rows active and
`shifting the active time of a row selection signal for each
`sequential row for a predetermined time.
`9. A driving method of an active matrix display device as
`in claim 8, wherein the driving elements of pixels of each
`
`8
`row are provided with a video signal through one of the
`plural signal lines formed in each column, after each row is
`made active by a selection signal and before the next row is
`made active by a selection signal.
`10. A driving method of an active matrix display device
`as in claim 7, wherein the signal provided for each column
`driving element by each signal line is temporarily capaci(cid:173)
`tively stored.
`11. A driving method as in claim 7 wherein the time that
`a row selection signal is active is substantially twice the time
`necessary to provide the video signals for each column to the
`driving elements of a row.
`12. A driving method as in claim 7 wherein the device
`pixels are driven in a noninterlaced mode.
`13. A driving method as in claim 7 wherein the time that
`a row selection signal is active is a product of the time
`necessary to provide said video signals for each column to
`the driving elements of a row and the number of the plurality
`20 of lines formed in each column.
`
`* * * * *
`
`Page 13 of 13
`
`