CN1369872A

CN1369872A - Active matrix type displaying unit

Info

Publication number: CN1369872A
Application number: CN01145757A
Authority: CN
Inventors: 宫岛康志
Original assignee: Sanyo Electric Co Ltd
Current assignee: Sanyo Electric Co Ltd
Priority date: 2000-11-06
Filing date: 2001-11-06
Publication date: 2002-09-18
Also published as: JP4017371B2; TW529001B; JP2002207442A; KR20020035444A; KR100472270B1

Abstract

Realize low power consumption of an active matrix type display device and realize circuit high precision. A holding circuit for holding an image signal is arranged in each pixel, and display is performed by switching between a normal operation mode and a memory operation mode. By sharing the power supply lines that can provide the drive voltage and reference voltage to the holding circuit 110 in two adjacent rows, the number of power supply lines can be reduced to half compared with the arrangement of power supply lines in each row, and the space efficiency of the circuit configuration can be improved, and the size of the circuit can be reduced. The circuit area of the circuit 110 is maintained. Since the holding circuit 110 is downscaled, the pixel size can be downscaled with high precision.

Description

Active matrix type display

Technical field that the present invention belongs to

The present invention relates to active matrix type display, particularly relate to the active matrix type display that designs a plurality of holding circuits corresponding to pixel.

Prior art

In recent years, as market demand, requiring display device is can portable display device, for example portable television, portable phone etc.Corresponding to such needs, just actively carry out miniaturization, the weight reduction for display device, the research and development of saving consumed power.

Liquid crystal indicator of the prior art (Liquid Crystal Display has been shown among Fig. 6; LCD) pixel electrode circuit structure diagram.(not shown) intersects to form signal line 51, drain signal line 61 on dielectric substrate, near the selection pixel selection TFT70 that design links to each other with two

signal line

51,61 this cross part.Select the source electrode 70s of pixel selection TFT70 to link to each other with the pixel electrode 17 of liquid crystal 21.

And, being designed for the auxiliary capacitor 85 that keeps the voltage of pixel electrode 17 in the field duration, a side terminal 86 of this auxiliary capacitor 85 links to each other with the source electrode 70s that selects pixel selection TFT70, applies the shared current potential of each pixel electrode on opposite side electrode 87.

Wherein, when on signal line 51, applying signal, select pixel selection TFT70 to become conducting state, transmit analog picture signal from drain signal line 61 to pixel electrode 17, and be maintained at auxiliary capacitor 85.The image signal voltage that is applied on the pixel electrode 17 is applied on the liquid crystal 21, and liquid crystal 21 is according to this voltage orientation.By such pixel electrode is configured to the rectangular LCD of acquisition.

Existing LCD can acquisition and moving image, the irrelevant demonstration of rest image.On LCD, show in the situation of rest image,, can show the image of dry cell for example as the battery allowance demonstration that on the part of portable phone liquid crystal display part, is used to drive portable phone.

But, for the liquid crystal indicator of said structure,, identical with the situation that shows moving image even under the situation that shows rest image, use signal to make and select pixel selection TFT70 to become conducting state, write picture signal once more to each pixel electrode and be necessary.

For this reason, be used to produce the drive circuit of drive signals such as signal and picture signal and produce the outside LSI that is used for Control Driver circuit operation various signals regularly since perseveration and always consume high-power.For this reason, if just have power-limited portable phone, then there is the defective that the up time shortens.

At this, open in flat 8-194205 number the spy liquid crystal indicator that possesses static memory at each pixel electrode has been shown.Quoting identical communique partial content illustrates.Fig. 7 is the planar circuit structural drawing that the spy opens the subsidiary active matrix type display of the holding circuit shown in flat 8-194205 number.Disposing a plurality of signal lines 51 and line of reference 52 on the line direction, on column direction, disposing a plurality of drain signal line 61 respectively.And, between holding circuit 54 and pixel electrode 17, be provided with TFT53.Owing to show that based on the data that in holding circuit 54, keep therefore, gate drivers 50, drain driver 60 stop, thereby reduce consumed power.

Fig. 8 is the circuit structure diagram of a pixel in the expression liquid crystal indicator.On substrate, pixel electrode is configured to matrix shape, between pixel electrode 17, towards paper left and right directions configuration signal line 51, configuration drain signal line 61 on above-below direction.And, with signal line 51 configured in parallel line of reference 52, holding circuit 54 is set at signal line 51 and drain signal line 61 cross sections, between holding circuit 54 and pixel electrode 17, on-off element 53 is set.Holding circuit 54 makes the formed storer of 2 grades of phase inverters, 55,56 positive feedbacks, and promptly static random-access memory (SRAM) is as the holding circuit of data image signal.Especially, SRAM is different from DRAM, owing to there is no need to upgrade the data that kept, and therefore relatively good.

Wherein, according to the 2 value digital signals that keep in static memory, on-off element 53 is controlled resistance value between line of reference Vref and the pixel electrode 17 according to the output of holding circuit 54, and adjusts the bias state of liquid crystal 21.On the other hand, input exchange signal Vcom in common electrode.If this device rest image display image does not ideally change, then there is no need storer is upgraded.

Technology of the present invention is dealt with problems

But, in holding circuit 54, use static memory RAM, the transistor number that constitutes holding circuit is 4 or 6 more than, has increased circuit area greatly.When between pixel electrode 17, arranging this static memory, exist the area of so-called pixel electrode 17 to diminish, the numerical aperture step-down of liquid crystal indicator, or make a pixel size become big and picture is difficult to the high precision int problem.

Therefore, the objective of the invention is in having the display device of holding circuit, make its more high precision or further improve numerical aperture.

The technology solution

Realize the present invention in order to solve the problems of the technologies described above, in active matrix type display, comprise: a plurality of pixel electrodes that become the ranks shape to arrange, a plurality of holding circuits of corresponding arrangement with pixel electrode, the power lead of predetermined voltage is provided for holding circuit, and the voltage of the data that will keep corresponding to holding circuit offers to pixel electrode, show, wherein, the direction of power lead in ranks extended, and share by the holding circuit corresponding with pixel electrodes arranged in one direction, share by the holding circuit corresponding simultaneously with adjacent pixel electrodes on another direction in ranks.

According to such structure, in having the active matrix display devices of holding circuit, compare with the situation of configuration power lead in every row, the bar number of power lead is kept to half, owing to can dwindle pixel size, so can be used as the active matrix display devices of degree of precision.

And, in active matrix display devices, has the ranks of being shape pixel electrodes arranged, a plurality of signal lines of on line direction, arranging, a plurality of drain signal line of on column direction, arranging, pixel capacitors is by being selected from the sweep signal of signal line, and from drain signal line supply picture signal, wherein, comprise: to providing by the selected pixel electrode of sweep signal corresponding to first display circuit from the signal of drain signal line picture signal by signal line input, voltage with the regulation of being supplied to is also according to the holding circuit of the signal maintenance of importing from the signal line from the picture signal of drain signal line, and show electrode is provided and second display circuit from the corresponding signal of the signal of this holding circuit, the circuit that is used for selectively first and second display circuit being linked to each other with selected drain signal line according to circuit selection signal is selected circuit, supply with to holding circuit extend on the direction of power lead at ranks of voltage of regulation and by with share in the corresponding holding circuit of this direction pixel electrodes arranged, share by a plurality of pixels adjacent on the ranks other direction simultaneously.

According to such structure, in one the active matrix display devices in may selecting first and second display circuits, and compare at each row configuration power lead, the bar number of power lead is kept to half, owing to dwindle pixel size, so can be as the active matrix display devices of degree of precision.

Most preferred embodiment is as follows.That is, connect 2 driving power supply lines that extend and provide different driving voltages on a direction of ranks at least in each holding circuit, at least one driving power supply line is shared by a plurality of pixels adjacent on the other direction of ranks.

And, in each holding circuit, connect at least 2 on a direction of ranks, extend and provide different reference voltage with reference to power lead, holding circuit selects reference voltage to offer pixel electrode according to the data that kept, and at least one is shared by a plurality of pixels adjacent on the ranks other direction with reference to power lead.

The power lead of sharing provides identical voltage to whole holding circuits.And, on the other direction of ranks between adjacent pixels near the power lead shared of configuration, configuration in the holding circuit of the other direction adjacent pixels of ranks is carried out in the following manner, promptly with on the other direction of ranks between the adjacent pixels as axle or center, and clamping shared power lead and is disposed symmetrically.

The accompanying drawing summary

Fig. 1 shows the circuit diagram of the present invention the 1st embodiment.

Fig. 2 illustrates the present invention's the 1st embodiment plane figure synoptic diagram.

Fig. 3 illustrates the present invention's the 1st embodiment plane figure synoptic diagram.

Fig. 4 is an embodiment of the invention sectional view.

Fig. 5 illustrates the present invention's the 2nd embodiment plane figure synoptic diagram.

Fig. 6 shows the circuit diagram of 1 pixel of liquid crystal indicator.

Fig. 7 is the circuit diagram that the display device that has holding circuit of prior art is shown.

Fig. 8 shows the circuit diagram that has 1 pixel of holding circuit liquid crystal indicator of prior art.

Embodiment of the present invention

The following describes display device with the relevant embodiment of the invention.The circuit structure diagram of employed display device of the present invention in liquid crystal indicator has been shown among Fig. 1.

In display panels 100, on dielectric substrate 10, be configured to a plurality of pixel electrodes 17 rectangular.And, arrange many signal lines 51 that link to each other with the gate drivers 50 that signal is provided in one direction, on crisscross, arrange a plurality of drain signal line 61 with this signal line 51.

In drain signal line 61, according to the timing from the sampling pulse of drain driver 60 output, sampling transistor SP1, SP2...SPn conducting provide the data-signal (analog picture signal or data image signal) of data signal line 62.

Gate drivers 50 is selected certain bar signal line 51, provides signal to it.Data-signal from drain signal line 61 is provided in the pixel electrode 17 of selected row.

Below, the detailed structure of each pixel is described.Near the cross section of signal line 51 and drain signal line 61, the loop of selecting TFT41 and N channel-type circuit to select TFT42 to form by P channel-type circuit is set selects circuit 40.Circuit selects TFT41, two drain electrodes of 42 all to link to each other with drain signal line 61, and these two drain electrodes link to each other with circuit selection signal line 88.Circuit selects TFT41,42 correspondences from the selection signal of selecting signal wire 88 and one of conducting.In addition, as will describing the back, to select circuit 40 to form a pair of with the loop, the loop is set selects circuit 43.But each transistor complementary operation of circuit 40,43 is selected in the loop, and P raceway groove, N raceway groove also can be reciprocal.Also can omit any one in the loop selection circuit 40,43.

Thus, select switching analog picture signal as the common operator scheme of describing later shows (corresponding panchromatic moving image) and shows that as the digital picture of storage operation pattern (low power consumption, corresponding rest image) becomes possibility.In addition, the pixel selection circuit 70 of selecting circuit 40 adjacent arrangements to form with the loop by N channel-type pixel selection TFT71 and N channel-type TFT72.Pixel selection TFT71,72 selects the circuit of circuit 40 to select TFT41,42 to be connected in series with the loop respectively, and has connected signal line 51 at its grid.Pixel selection TFT71,72 constitutes can be according to two conductings simultaneously of signal from signal line 51.

Auxiliary capacitor 85 is set is used to keep analog picture signal.One termination electrode of auxiliary capacitor 85 links to each other with the source electrode of pixel selection TFT71.Other end electrode links to each other with shared auxiliary capacitance line 87, and bias voltage Vsc is offered this other end electrode.The source electrode of pixel selection TFT71 selects TFT44 and contact point 16 to link to each other with pixel electrode 17 by circuit.By signal, the gate turn-on of pixel selection TFT70 will provide the analog picture signal that comes to be input to the pixel electrode 17 from drain signal line 61 by contact point 16, and as the pixel voltage drive liquid crystal.Though pixel voltage must remain to 1 field interval selecting once more next time from the selection of removing pixel selection TFT71, but if only rely on liquid crystal capacitance, along with can reducing gradually of time, and in 1 field interval, can not fully keep pixel voltage through pixel voltage.Like this, the pixel voltage reduction can cause and show inhomogeneous and can not obtain good demonstration.Therefore, auxiliary capacitor 85 is set so that in 1 field interval, keep pixel voltage.

Between auxiliary capacitor 85 and pixel electrode 17, the P channel-type TFT44 that circuit 43 is selected in the loop is set, constitute like this so that can select the circuit of circuit 40 to select TFT41 conducting one simultaneously to end with the loop.With circuit select the TFT41 conducting, the operator scheme that simulating signal is provided and drives liquid crystal at any time is called routine operation pattern or simulated operation pattern.

Between the TFT72 of pixel selection circuit 70 and pixel electrode 17, holding circuit 110 is set.Holding circuit 110 is made up of 2 inverter circuits and the signal selecting circuit 120 of positive feedback, and has constituted the static memory that keeps numeral 2 values.

Signal selecting circuit 120 is according to the circuit of selecting signal from the signal of 2 phase inverters, and is made of 2 N channel-type TFT121,122.Owing to applied the complementary output signal from 2 phase inverters respectively in TFT121,122 grid, so TFT121,122 complementary conductings end.

Here, select AC driving signal (signal B) during the TFT122 conducting, select to equal the AC driving signal (signal A) of reverse electrode signal Vcom during the TFT121 conducting, offer the pixel electrode 17 of liquid crystal 21 by the TFT45 that selects circuit 43.Circuit is selected the TFT42 conducting, and the operator scheme that shows based on the data that keep in holding circuit is called as memory mode or digit manipulation pattern.

Said structure can be summarized as, in 1 pixel electrode, be provided with: by as the pixel selection TFT71 of pixel selection element and keep circuit (simulation display circuit) that the auxiliary capacitor 85 of analog picture signal forms and by as the TFT72 of pixel selection element and the circuit (digital display circuit) that keeps the holding circuit 110 of 2 value data image signals to form, in addition, be provided for selecting the loop of these two circuit to select circuit 40,43.

Secondly, the peripheral circuit of liquid crystal panel 100 is described.In the additional circuit substrate 90 of the dielectric substrate 10 of liquid crystal panel 100 and other substrate, panel driving LSI91 is set.Import vertical enabling signal STV, to drain driver 60 in input level enabling signal STH with LSI91 to gate drivers 50 from the panel driving of this additional circuit substrate 90.Received image signal in data line 62.

Below, the driving method of said structure display device is described.

(1) situation of routine operation pattern (simulated operation pattern)

According to mode signal, one selects the simulation display mode, just LSI91 is set at the state that simulating signal is provided to data signal line 62, and coincidence circuit selects the current potential of signal wire 88 just to become L, the loop selects the circuit of circuit 40,43 to select TFT41,43 conductings, and circuit selects TFT42,45 to end.

According to the sampled signal corresponding to horizontal enabling signal STH, sampling transistor SP conducting successively offers drain signal line 61 with the analog picture signal of data wire size line 62.

Based on vertical enabling signal STV, signal is offered signal line 51.According to signal, during pixel selection TFT71 conducting, just be transmitted to pixel electrode 17 from the analog picture signal An.Sig of drain signal line 61, and remain on auxiliary capacitor 85.The image signal voltage that will apply on pixel electrode 17 imposes on liquid crystal 21, by according to this voltage liquid crystal 21 orientations being obtained liquid crystal display.

For the simulation display mode,, therefore can show panchromatic moving image preferably owing to drive liquid crystal at any time according to the simulating signal of input at any time.But, for LSI91, any in each

driver

50,60, the constantly consumed power that drives additional circuit substrate 90.

The situation of (2) storage operation pattern (digital display mode)

According to mode signal, one selects digital display mode, and LSI91 just carries out digital conversion to picture signal, and the numerical data that will take out high order bit is set at the state to data signal line output, and simultaneously, the current potential of loop selection signal wire 88 just becomes H.Operation like this, because when the loop selected the circuit of circuit 40,43 to select TFT41,43 to end, circuit was selected TFT42,45 conductings, therefore, holding circuit 110 just becomes effective status.

In addition, import enabling signal STHs with LSI91 to gate drivers 50 and drain driver 60 from the panel driving of additional circuit substrate 90.Corresponding therewith, produce sampled signal successively, according to each sampled signal, sampling transistor SP1, SP2 ... SPn is conducting successively, and sampling also provides data image signal D.Sig to each drain signal line 61.

Here, illustrate that having applied first row is the signal line 51 of signal G1.At first, by signal G1, each pixel selection TFT72 of each pixel electrode that links to each other with signal line 51 is in the horizontal scan period conducting.Note first row, the first row pixel electrode, by sampled signal SP1, the data image signal S11 that arrives to drain signal line 61 input samples.Then, select pixel selection TFT72 to become conducting state by signal, just to holding circuit 110 supplied with digital signal D.Sig, and by 2 phase inverters maintenances.

The signal that is kept by this phase inverter is input in the signal selecting circuit 120, selects signal A or signal B in this signal selecting circuit 120, is applied in the pixel electrode 17 signals selected, and this voltage is applied in the liquid crystal 21.

Then, by the signal line since first row is scanned till delegation's signal line to the end, 1 picture (1 field interval) scanning is that whole spot scans finish, and just shows a width of cloth picture.

Here, when showing a width of cloth picture, stop to gate drivers 50 and drain driver 60 and add panel driving providing voltage, thereby stop its driving with LSI91.In holding circuit 110, provide driving voltage VDD, VSS to drive usually, provide reverse electrode voltage to reverse electrode 32, give and select circuit 120 that signal A and B are provided.

Promptly, in holding circuit 110, drive driving voltage VDD, the VSS that this holding circuit is used, apply reverse electrode voltage VCOM to reverse electrode, display panels 100 is in the situation of conventional power (NW), signal A is applied AC drive voltage with reverse electrode voltage same potential, signal B is applied alternating voltage (for example 60Hz) so that drive liquid crystal.Thus, can keep a width of cloth picture and be shown as still frame.In addition, other gate drivers 50, drain driver 60 and add and become the state that does not apply voltage among the LSI91.

At this moment, in drain signal line 61, import in the situation of H (height) signals to holding circuit 110 by data image signal, because input " L " causes a TFT121 to become ending in a TFT121 in signal selecting circuit 120, on the other hand, to 2TFT122 input " H " 2TFT122 being become ends.Thus, select signal B, apply the voltage of signal B to liquid crystal.That is, apply the alternating voltage of signal B, owing to raise by the electromotive force of electric field generation liquid crystal, the demonstration that can observe the NW display panel becomes black the demonstration.

In drain signal line 61, by data image signal when the holding circuit 110 input L, because signal selecting circuit 120 is imported " H " and caused a TFT121 to become conducting in a TFT121, on the other hand, to 2TFT122 input " L " 2TFT122 is become and end.Thus, select signal A, apply the voltage of signal A to liquid crystal.That is, owing to apply and reverse electrode 32 identical voltages, do not produce electric field, the electromotive force of liquid crystal does not raise, and the demonstration that can observe the NW display panel becomes white demonstration.

Thus, by writing a secondary picture and it being kept showing rest image, in this case,, can reduce corresponding therewith consumed power owing to stop the driving of each

driver

50,60 and LSI91.

For the foregoing description, holding circuit 110 only keeps 1 bit, certainly, if holding circuit is compared specialization more, then can carry out the gray scale demonstration by enough memory modes, if with the storer of holding circuit as the storage analogue value, then also the available memory operator scheme is carried out panchromatic demonstration.

As mentioned above, according to embodiments of the invention, use 1 display panels 100 can carry out corresponding so-called two kinds of demonstrations: panchromatic moving image shows (situation of simulation display mode), and the low consumpting power digital gray scale shows (situation of digital display mode).

Secondly, the layout of the embodiment of the invention is described with Fig. 2.Fig. 2 shows the synoptic diagram of the layout of current embodiment.The loop that is connected in series selects the P P-channel circuit of circuit to select the N raceway groove pixel selection TFT71 of TFT41, pixel selection circuit, loop to select the P P-channel circuit of circuit to select TFT44, and is connected with auxiliary capacitor 85 when being connected to pixel electrode 17 by contact point 16.Connecting the N raceway groove by contact point 16 in pixel electrode 17 selects TFT circuit 42, N raceway groove pixel selection TFT72, holding circuit 110 and loop to select the N channel TFT 45 of circuit.Said structure all is an overlay configuration on pixel electrode 17.

The circuit structure that disposes in each pixel is because roughly the same in each pixel, and therefore showing greatly between the mutual pixel in the circuit arrangement between the adjacent pixels on the column direction is that axle becomes a line symmetry.That is, for figure the last the 1st pixel that lists, the pixel upper end disposes signal line 51, and pixel the latter half disposes holding circuit 110.For last the 2nd row pixel of figure, the pixel lower end disposes signal line 51, and pixel the first half disposes holding circuit 110.Similarly, have and the identical configuration of the 1st row for the 3rd row that do not illustrate on the figure: signal line 51 is in the upper end, and holding circuit 110 is configured in the latter half.

As mentioned above, holding circuit 110 is SRAM.In holding circuit 110, be connected with 2 kinds of height 2 kinds of driving power supply lines (LVDD, LVSS), height with reference to power lead (signal A, signal B) 4 power leads altogether.These power leads extend on line direction, and are identical with signal line 51, auxiliary capacitance line 87, all shared these power leads of each pixel of this row.It more than is the common ground during image element circuit is arranged.For current embodiment, the layout difference of each image element circuit.The layout of each image element circuit is being the layout of line symmetry each other between neighbor on the column direction.It is shared that 110,4 power leads of holding circuit that disposing adjacent pixels on column direction close to each other with 4 power leads of clamping become 110 of both sides' holding circuits.That is, dispose each bar power lead, and the whole holding circuits corresponding with 2 row pixels link to each other with 1 ratio of configuration in 2 row pixels.Therefore, compare and to reduce the quantity of half with the power lead that on line direction, extends of configuration in each row.Have the active matrix type display of holding circuit 110 because the circuit that is provided with is many in each pixel, therefore reduce the circuit structure element, just can cause dwindling elemental area.Therefore, can make the display device high precision int that has holding circuit.

For example, because signal line 51 is necessary to make its conducting with different timings in each row, therefore can not in different rows, cross-over connection share.In contrast, Gong You 4 power leads provide the line of holding circuit 110 driving voltages and reference voltage in the present embodiment, regardless of being pixel selection, not selecting and pixel displaying contents (white, black), all providing the common voltage that applies continuously in the pixel holding circuit 110.Thus, can be in a plurality of row cross-over connection shared.Based on same reason, active matrix type display can carry out colour and show that neighbor each other can the common source line.That is, the present invention not only can arrange with a kind of color bar line on column direction, but also can implement the data ordering that RGB differentially disposes respectively mutually equally.

Secondly, the relation on above-mentioned 4 power leads and pixel electrode 17 layouts is described.Fig. 3 shows the schematic layout pattern of the boundary member of neighbor GS1, GS2 on Fig. 2 column direction.As shown in the figure, the power lead of being shared by 2 pixel GS1, GS2 19 (being the power lead LVDD to the SRAM of holding circuit 110 power supply in the drawings) is in side's pixel for example on the pixel GS2 during overlap extension, respectively to pixel GS1, GS2 direction upper bifurcation, source electrode 110S, the 110S with the thin film transistor (TFT) TFT that constitutes each SRAM contacts by

contact point

18,18 in the way.

In such layout, between the pixel electrode 17 of pixel GS2 and power lead 19, form stray capacitance by dielectric film.Because it is very big that this stray capacitance is compared with the stray capacitance that forms between the pixel electrode 17 of pixel GS and power lead 19, therefore the influence for the

pixel electrode

17,17 of stray capacitance just becomes imbalance.For this reason, produce the influence of stray capacitance in each pixel, striped anyhow occurs on picture, display quality reduces.

Therefore, power lead 19 not with the pixel GS1 of the overlapping side of pixel electrode 17 in, power lead 19 by the design bifurcated is expanded the overlapping region 20 that forms on pixel electrode 17, increase the stray capacitance between pixel electrode 17 and the power lead 19, the stray capacitance balance that itself and neighbor GS2 are had is eliminated the influence of stray capacitance.Here, preferably pass through the expansion overlapping region 20 of designing power supply line 19, so that for neighbor GS1, GS2, the parasitic capacitance value that forms equates between pixel electrode 17 and power lead 19.

Power lead 19 is not limited to the high voltage one end driving power supply line (LVDD) of holding circuit 110, can also be with reference to low-voltage one end of power lead (signal A, signal B), holding circuit 110 driving power supply line (LVSS), transmit signal B with reference to one in the power lead.

For above-mentioned layout,, there is no need to overlap on the pixel electrode 17 though power lead 19 can directly carry out capacitive coupling by overlapping on the pixel electrode 17.For example, in the situation about linking to each other between the source electrode that makes TFT by intermediate electrode layer and pixel electrode 17, power lead 19 by the target interlayer indirectly and pixel electrode 17 capacitive coupling.But, on pixel electrode 17, expand the overlapping region 20 that constitutes for said power 19, there is no need to overlap on the pixel electrode 17, overlappingly on intermediate electrode layer as mentioned above also can reach identical effect.

But the LCD of present embodiment is a reflection type LCD.Figure 4 illustrates Fig. 2 A-A ' cross-sectional view of the reflection type LCD of present embodiment.On a side dielectric substrate 10, be arranged with the island semiconductor layer 11 that forms by polycrystal silicon, cover on it and disposed gate insulating film 12.As the top of semiconductor layer 11, on gate insulator 12, disposed grid 13, the lower floor's semiconductor layer 11 in the both sides that are arranged in this grid 13 is formed with source electrode and drain electrode.On source electrode 13 and gate insulating film 12, its covering is formed interlayer insulating film 14.Then, with drain electrode and source electrode correspondence position on form contact point, by this contact point, drain electrode links to each other with pixel selection TFT71, source electrode passes through contact point 16 and links to each other with pixel electrode 17.Each pixel electrode 17 that forms on smooth insulation film 15 is to be made of aluminium reflecting materials such as (Al).On each pixel electrode 17 and smooth insulation film 15, form the alignment films of forming by with the polyimide of liquid crystal 21 orientations 20.

On other dielectric substrate 30, reverse electrode 32 that order formation red by presenting (R), green (G), blue versicolor colored filters 31 such as (B), ITO transparent and electrically conductive films such as (Indium Tin Oxide) are formed and the alignment films 33 that liquid crystal 21 is orientated.Certainly, in not preparing to carry out colored situation about showing, do not need colored filter 31.

Paste so periphery of a pair of insulativity substrate 10,30 of formation, filling liquid crystal 21 between the slit that forms thus by the adhibit quality encapsulant.

For reflection type LCD, shown in the figure dotted line,, and, can observe its demonstration to the ejaculation of observer's 1 one sides by the exterior light of pixel electrode 17 reflections from the 30 1 side incidents of insulativity substrate.

Therefore which kind of element reflection type LCD disposes because light can not see through pixel electrode 17 below pixel electrode 17, can the logarithm value aperture not influential.Therefore, by needing larger area holding circuit 110, can obtain and the common identical pixel separation of LCD in 17 times configurations of pixel electrode.As current embodiment, need below pixel electrode, not dispose complete structure, can be between pixel electrode the configuration section structure.

Secondly, with reference to description of drawings the present invention the 2nd embodiment.Fig. 5 shows the synoptic diagram of current embodiment plane figure.Current embodiment is the striped arrangement of RGB shades of colour pixel adjusting to a line configuration, in each pixel electrode 17, arranges corresponding to any colored filter of RGB, illustrates as 17R, 17G, 17B in the drawings.Each pixel of RGB has the circuit identical with Fig. 2, so that in each pixel, keep the data of each pixel in holding circuit 110.

Current embodiment is characterised in that the circuit layout in the layout, holding circuit, selection circuit, auxiliary capacitor of pixel electrode 71 is inconsistent.To describe this difference in detail below.Concerned pixel electrode 17R at first.Arrange pixel electrode 17R in accompanying drawing left side, it is long rectangular-shaped for presenting on above-below direction.The contact point that comes remarked pixel electrode 17R to link to each other with 16R with this circuit.Then, the circuit that is connected in series is selected TFT41R, 44R, pixel selection TFT71R, and wherein a part extends to the pixel electrode 17G as neighbor.Similarly, auxiliary capacitor 85R, holding circuit 110R also extend to pixel electrode 17G.Pixel electrode 17G links to each other with related circuit by contact point 16G, circuit selection TFT41G, pixel selection TFT71G, auxiliary capacitor 85G, holding circuit 110G overlapping arrangement on as the pixel electrode 17R of neighbor.

The circuit corresponding with

pixel electrode

17R, 17G shared signal line 51, and a bit be that the mutual point symmetry in center disposes on the signal line.Below similarly, corresponding with pixel electrode 17B circuit extends to the adjacent illustrated pixel electrode that do not have.If this pixel is pixel electrode 17R ', the circuit corresponding with pixel electrode 17R ' overlaps on the pixel electrode 17B conversely.

The following describes the advantage of configuration like this.For example, as a color pixel, when this pixel was used for the cardinal principle square, each pixel of RGB became vertical rectangle of 3: 1 with RGB3.Each pixel of RGB of general striped arrangement becomes rectangle long on the direction.Below the pixel electrode 17 of like this elongated rectangular, thereby when adjusting layout and arranging holding circuit 110, can cause the difficulty of circuit design.In contrast, according to the present invention, because the layout of pixel electrode 17 is different with circuit layout, circuitous just the becoming of unnecessary wiring there is no need, and therefore improved space efficiency, can reduce the required area of holding circuit.In the situation for the LCD that has holding circuit,, therefore, dwindle holding circuit and can directly cause the height of LCD to become more meticulous owing to mainly be that the shared area of holding circuit is overriding in the minimum area of 1 pixel.

Secondly, the following describes the clamping grid signal wire advantage of configuration circuit symmetrically.Between neighbor in the situation of shared region owing to must adjust circuit layout in each pixel, if therefore neighbor to each other point symmetry dispose, design an image element circuit, can this circuit of reflective design, thereby the raising circuit layout efficiency.But, be necessary to adjust with figure in the line of 4 power leads shown in the pixel upper and lower side.And circuit layout is not a point symmetry, and parallel when mobile when making progress, neighbor signal line each other is necessary to be separated from each other arrangement, is necessary 2 signal lines of every row configuration.In contrast, for current embodiment, because the symmetric offset spread circuit, so 1 of the every row of signal line get final product, do not have necessity of increase.

Current embodiment is identical with first embodiment, dispose holding circuit 110 in pixel upper end and lower end, in the holding circuit between the neighbor 110 on the column direction by clamping power lead (VDD, VSS, signal A, signal B) mode neighbor configuration, and shared these 4 power leads.Therefore, identical with first embodiment, and compare when the every row configuration power lead, power lead can be subdued and be half.

For above-mentioned first, second embodiment, though neighbor can shared 4 power leads, there is no need must shared whole power leads.Closely during 4 power leads of disposed adjacent, in order to link to each other, begin to the wiring of column direction upper bifurcation to produce stray capacitance owing to intersect with whole other 3 power leads from each power lead with holding circuit 110.And, between the holding circuit 110 of the layout of for example current embodiment and auxiliary capacitor 85, during 1 power lead of configuration, can estimate that comp comprehensive layout's effect is better.For this situation, preferably can shared 4 power leads in any power lead.

For above-mentioned first, second embodiment, share the result of power lead, complete line symmetry of circuit arrangement rather than point symmetry exist the stray capacitance that forms between each power lead and the pixel electrode 17 in the different each other situation of pixel.Like this, in pixel signal delay difference to each other, the worry that has display quality to descend.Thus,, 2n (n is a natural number) bar is arranged,, the 2n+1 bar is arranged,, preferably dispose 1 power lead between pixel then at each pixel overlay configuration n bar if share power lead then at each pixel overlay configuration n bar if share power lead in order to make the stray capacitance unanimity.

In above-mentioned first, second embodiment, article 4, power lead (VDD, VSS, signal A, signal B) extends on line direction, although understand the situation that neighbor is shared to each other on column direction, and still, shown in Fig. 1 circuit diagram, also can on column direction, extend configuration.For this situation, with between the row serve as axle to make each pixel circuit configuration be the line symmetry, shared power lead can obtain the identical effect with the 1st, the 2nd embodiment.But, especially for as the sort of situation of the 2nd embodiment layout arrangement, the surplus of layout of extending wiring on column direction is few.Therefore, the layout method that extends on line direction of power lead is relatively good.

In the above-described embodiments, though use reflection type LCD to be illustrated,, can also be applicable to transparent type LCD, can be with transparent pixel electrode and holding circuit overlay configuration.Yet, for transparent type LCD, because the local shading of having disposed metal line can not avoid numerical aperture to reduce.And, in transparent LCD, when below pixel electrode, having disposed holding circuit, may make the transistor maloperation of holding circuit and selection circuit owing to the light that sees through, therefore, be necessary on the grid of all crystals pipe, to add photomask.Therefore, for transparent type LCD, improve numerical aperture and have any problem.

In contrast, can not influence its numerical aperture even what circuit reflection type LCD disposes below pixel electrode.In addition, such for the transparent liquid crystal display device, owing to there is no need to use so-called back of the body irradiation, therefore do not need to light the power of back of the body irradiation observer and opposite side.The initial purpose that has the LCD of holding circuit is in order to reduce consumed power, as display device of the present invention, is applicable to that the reflection type LCD of the low consumpting power that need not carry on the back irradiation is relatively good.

Though the foregoing description uses liquid crystal indicator to be illustrated, the present invention is not limited to this, can also be applicable to various display device such as organic EL display, LED display device.

The invention effect

As mentioned above, active matrix type display of the present invention is such display unit: have correspondence In the active matrix type display of the holding circuit of pixel electrode, be connected in the power line example of holding circuit Such as upper extension the in the row direction, and by sharing in holding circuit corresponding to the pixel electrode of arranging with line direction, And shared by the holding circuit corresponding with pixel electrode adjacent on column direction simultaneously, therefore with join at each row Put the situation of power line and compare, the number of power line can be subdued half, owing to can dwindle pixel size, Therefore can become the active matrix type display with the high accuracy holding circuit.

Especially, because total power line provides identical voltage for whole holding circuits, therefore, can be whole Share these power lines on individual line direction and the column direction.

Especially, near between the pixel adjacent on the other direction of ranks, dispose shared power line, be expert at The configuration of the holding circuit of neighbor on the other direction of row is owing to be other direction neighbor with ranks Between be axle or center, share power line by clamping and come balanced configuration, therefore from share power line to the guarantor Hold the continuous wiring of circuit and just shorten, can improve positioning efficiency.

Claims

1. active matrix type display, comprise a plurality of pixel electrodes that are the configuration of ranks shape, a plurality of holding circuits of corresponding configuration, the power lead of predetermined voltage is provided for above-mentioned holding circuit with pixel electrodes, the corresponding voltage of the data that kept with above-mentioned holding circuit is provided and shows to pixel electrodes, it is characterized in that

Said power is extended in any one direction of ranks, and by sharing in the holding circuit that is arranged in the pixel electrode correspondence on the above-mentioned direction, is shared by the holding circuit of adjacent pixel electrodes correspondence on any other direction of ranks simultaneously.

2. active matrix type display, has the pixel electrode that is the configuration of ranks shape, in a plurality of signal lines that dispose on the line direction, a plurality of drain signal line that on column direction, dispose, pixel electrodes is by being selected from the sweep signal of above-mentioned signal line, and provide picture signal from described drain signal line, it is characterized in that comprising:

To offer the 1st display circuit corresponding to signal from the picture signal of described drain signal line by the selected pixel electrode of sweep signal of above-mentioned signal line input,

The 2nd display circuit, have to have and be provided predetermined voltage, and keep holding circuit from the picture signal of described drain signal line according to sweep signal from the input of above-mentioned signal line, to above-mentioned show electrode provide with from the corresponding signal of this holding circuit signal

Circuit is selected circuit, is used for linking to each other with above-mentioned drain signal line with the 2nd display circuit the above-mentioned the 1st selectively corresponding to circuit selection signal,

Provide the power lead of predetermined voltage on any one direction of ranks, to extend to above-mentioned holding circuit and share by the holding circuit that is arranged in the pixel electrode correspondence on the above-mentioned direction, simultaneously by with ranks in share in adjacent a plurality of pixels on any other direction.

3. active matrix type display as claimed in claim 1 or 2, it is characterized in that, in above-mentioned each holding circuit, at least connect 2 driving power supply lines that extend and provide different driving voltage in ranks on any one direction, at least one driving power supply line is by sharing in a plurality of pixels adjacent on the other direction of ranks.

4. active matrix type display as claimed in claim 3, it is characterized in that, enlarged area is set, make the above-mentioned driving power supply line shared by mutual neighbor and the capacity coupled while of pixel electrode of side's pixel, make the pixel electrode capacitive coupling of above-mentioned driving power supply line and the opposing party's pixel.

5. active matrix type display as claimed in claim 3, it is characterized in that, make the above-mentioned driving power supply line of sharing by mutual adjacent pixels overlapping, and on the pixel electrode of the opposing party's pixel, the overlapping region that enlarges above-mentioned driving power supply line formation is set with the pixel electrode of side's pixel.

6. active matrix type display as claimed in claim 1 or 2, it is characterized in that, in above-mentioned each holding circuit, be connected that any side in the ranks is upwardly extending to provide at least 2 of different reference voltage with reference to power lead, above-mentioned holding circuit according to maintenance data select above-mentioned reference voltage and offer pixel electrodes, in ranks on any other direction adjacent a plurality of pixels share at least 1 above-mentioned with reference to power lead.

7. active matrix type display as claimed in claim 6, it is characterized in that, the design enlarged area, make the above-mentioned driving power supply line shared in mutual neighbor and the pixel electrode capacitive coupling of side's pixel, make the pixel electrode capacitive coupling of above-mentioned driving power supply line and the opposing party's pixel simultaneously.

8. active matrix type display as claimed in claim 6, it is characterized in that, make the above-mentioned driving power supply line of sharing by mutual neighbor overlapping, and on the pixel electrode of the opposing party's pixel, the overlapping region that enlarges above-mentioned driving power supply line formation is set with the pixel electrode of side's pixel.

9. active matrix type display as claimed in claim 1 or 2 is characterized in that, above-mentioned shared power lead provides identical voltage to all holding circuits.

10. active matrix type display as claimed in claim 1 or 2, it is characterized in that, in ranks on any other direction between the adjacent pixels near the configuration above-mentioned shared power lead, in ranks on any other direction the configuration of the above-mentioned holding circuit of adjacent pixels be with on any other direction in above-mentioned ranks between the adjacent pixels serve as the axle or the center, the above-mentioned shared power lead of clamping disposes symmetrically.