JP3564990B2 - Electro-optical devices and electronic equipment - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention belongs to a technical field of an electro-optical device such as a liquid crystal panel of an active matrix driving method by driving a thin film transistor (hereinafter referred to as a TFT) or the like, or an electronic device using the electro-optical device. And a driving circuit including a sampling circuit, an electro-optical device, and an electronic apparatus.
[0002]
[Prior art]
Conventionally, in an active matrix driving type liquid crystal panel by TFT driving, a large number of scanning lines and data lines arranged vertically and horizontally and a large number of pixel electrodes corresponding to intersections of the scanning lines and data lines are formed on a TFT array substrate. It is provided in. In addition, in addition to these, various peripheral circuits including a TFT as a component, such as a scan line driver circuit, a data line driver circuit, a sampling circuit, and a precharge circuit, may be provided on such a TFT array substrate. .
[0003]
Among these peripheral circuits, a sampling circuit is a circuit that samples an image signal in order to stably supply a high-frequency image signal to each data line at a predetermined timing in synchronization with a scanning signal. In addition, various peripheral circuits using TFTs and the like can be provided on the TFT array substrate from the viewpoints of improving image quality in liquid crystal displays, reducing power consumption, reducing costs, and the like.
[0004]
Further, the precharge circuit is provided at the timing at which the image signal is sampled by the sampling circuit with respect to the data line for the purpose of improving the contrast ratio, stabilizing the potential level of the data line, and reducing line unevenness on the display screen. This circuit reduces the load when writing an image signal to a data line by supplying a precharge signal (image auxiliary signal) at a preceding timing. In particular, in the so-called 1H inversion driving method in which the voltage polarity of the data line, which is usually performed for AC driving of the liquid crystal, is inverted every one horizontal scanning period, in one horizontal retrace period before one horizontal effective display period, If a precharge signal of a predetermined potential is previously written to the data line after the polarity of the image signal is switched, the amount of charge required when writing the image signal to the data line can be significantly reduced.
[0005]
Here, in a screen display area defined by a plurality of pixels arranged in a matrix on the TFT array substrate, that is, in an area where an image is actually displayed on the liquid crystal panel due to a change in the alignment state of the liquid crystal, the plurality of pixels are displayed. In order to control the pixel switching TFT provided in each pixel, it is said that the larger the area for forming a peripheral circuit provided around the screen display area, the larger the basic requirement.
[0006]
However, in order to further improve the resolution, the liquid crystal panel is required to have a higher definition, or to increase the number of pieces to be removed from the mother board to improve the yield, or to be used in a mobile application that can be carried freely. Many voices are requesting the miniaturization of itself. As described above, as the definition of the liquid crystal panel becomes higher or the size of the liquid crystal panel becomes smaller, it becomes necessary to make the pixel size finer, and accordingly, it is necessary to integrate peripheral circuits formed on the same substrate.
[0007]
Therefore, in order to integrate the peripheral circuits, the precharge circuit and the sampling circuit may be provided on the same side of a screen display area of a liquid crystal panel. The precharge circuit and the sampling circuit are provided in parallel with the data line on the side where the image signal is supplied to the data line by the data line drive circuit and the sampling circuit. With such a configuration, there is no need to provide a precharge circuit at the other end of the data line, that is, on the side opposite to the side to which the image signal is supplied, as in the prior art. A signal line and a precharge circuit drive signal line for controlling the precharge circuit do not have to be routed around the screen display area.
[0008]
[Problems to be solved by the invention]
However, according to the above-described configuration of the conventional precharge circuit and sampling circuit, the precharge circuit and the sampling circuit need to be continuously formed on the same side, and occupy a predetermined range of the area on the substrate. Therefore, there is a problem that it is difficult to integrate the precharge circuit and the sampling circuit and to downsize a liquid crystal panel including the precharge circuit and the sampling circuit.
[0009]
That is, the switching means constituting the precharge circuit must be provided for each data line, and a wiring extending from the precharge circuit drive signal line and the precharge signal line must be provided. Similarly, the switching means constituting the sampling circuit must be provided for each data line, and a wiring extending from the sampling circuit drive signal line and the image signal line must be provided. As a result, when the size of the liquid crystal panel is reduced, it is difficult to form the precharge circuit and the sampling circuit in parallel, and as a result, the precharge circuit and the sampling circuit cannot be integrated.
[0010]
Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to efficiently arrange the precharge circuit and the sampling circuit on a substrate to reduce the size of the electro-optical device. Another object of the present invention is to provide a simple electro-optical device and an electronic apparatus including the electro-optical device.
[0011]
[Means for Solving the Problems]
In order to solve the above-described problem, an electro-optical device according to the present invention includes a plurality of pixel electrodes, a plurality of data lines to which an image signal is supplied, a plurality of scanning lines to which a scanning signal is supplied, and the data line. And a first switching unit interposed between the pixel electrode and the first switching unit, the conduction state and the non-conduction state between the data line and the pixel electrode being controlled based on a scanning signal supplied to the scanning line. An electro-optical device comprising:From the image signal line based on the sampling circuit drive signalA sampling circuit having second switching means for sampling the image signal and supplying the image signal to the data line; and a sampling period for supplying the image signal to the data line.From the precharge signal line based on the precharge circuit drive signalPrecharge signal to the data lineSupplyA precharge circuit having a third switching means, wherein the sampling circuit is arranged between the image display region in which the pixel electrode is formed and the precharge circuit.
[0012]
According to the electro-optical device of the present invention, the plurality of third switching units are formed for each data line in an area on the substrate different from the image display area, and before the supply of image signals, A pre-charge signal set in advance is supplied. On the other hand, the plurality of second switching means are formed for each data line in an area on the substrate between the area where the third switching means is formed and the image display area, and apply an image signal to each data line. Supply. Therefore, in the positional relationship between the third switching means and the second switching means, the second switching means for supplying the image signal is closer to the image display area, so that the image signal between the image display area and the second switching means is provided. Of the image signal to be supplied to the pixel electrode can be prevented from being deformed in waveform.
[0013]
Further, the third switching means of the present invention is a thin film transistor, a supply line extending from the precharge signal line is electrically connected to a source electrode of the thin film transistor, and the data line is connected to a drain of the thin film transistor. It is characterized by being electrically connected to the electrode.
[0014]
According to this configuration, the plurality of image signal supply lines disposed on the substrate between the region where the third switch is formed and the region where the second switch is formed, transfer the image signal to the second line. Each is supplied to the switching means. Therefore, since the plurality of image signal supply lines for supplying the image signal are arranged on the substrate between the area where the third switch is formed and the area where the second switch is formed, the image signal supply line is provided. The path of the image signal from the supply line to the pixel electrode via the second switching means can be shortened and the resistance can be reduced.
[0015]
The second switching means of the present invention is a thin film transistor, a relay line extending from the image signal line is electrically connected to a source electrode of the thin film transistor, and the data line is connected to a drain electrode of the thin film transistor. Is electrically connected to the power supply.
[0016]
According to this configuration, since the second switching means and the third switching means are each a thin film transistor, the size of the liquid crystal driving device can be reduced.
[0017]
The third switching means may be constituted by at least a P-channel transistor or an N-channel transistor.
[0018]
According to this configuration, the third switching means constituting the precharge circuit is constituted by a single-channel TFT such as a P-channel TFT or an N-channel TFT, so that the third switching means can be efficiently arranged in a region occupying a small area. Can be. As a result, the precharge circuit can be integrated, and the size of the electro-optical device can be reduced.
[0019]
Further, it is preferable that the second switching means includes at least a P-channel transistor or an N-channel transistor.
[0020]
According to this configuration, the second switching means constituting the sampling circuit is constituted by a single-channel TFT such as a P-channel TFT or an N-channel TFT, so that the second switching means can be efficiently arranged in a region having a small occupied area. it can. Thus, the sampling circuit can be integrated, and the size of the liquid crystal panel can be reduced.
[0021]
According to another aspect of the invention, an electronic apparatus includes the above-described electro-optical device.
[0022]
Since the electronic device includes the above-described electro-optical device, the size of the electro-optical device can be reduced, so that the size of the electronic device can be reduced.
[0023]
The operation and other advantages of the present invention will become more apparent from the embodiments explained below.
[0024]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, a preferred embodiment of the present invention will be described with reference to the drawings.
[0025]
Each of the embodiments described below is an embodiment in which the present invention is applied to a projection-type liquid crystal device that transmits light from a light source and displays an image.
[0026]
(I)First embodiment
(A)Structure of liquid crystal device
First, the configuration of the liquid crystal device according to the first embodiment will be described with reference to FIGS.
[0027]
First, an overall configuration of a liquid crystal device, which is an example of the electro-optical device according to the first embodiment, will be described with reference to FIGS. Here, FIG. 1 is a block diagram showing a configuration of various wirings, peripheral circuits, and the like provided on a TFT array substrate in the liquid crystal device of the first embodiment, and FIG. 2 shows a TFT array substrate formed thereon. FIG. 3 is a plan view of the components viewed from the counter substrate side, and FIG. 3 is a cross-sectional view taken along the line HH ′ of FIG.
[0028]
As shown in FIG. 1, the liquid crystal device 200 includes a TFT array substrate 1 made of, for example, a quartz substrate, hard glass, or the like. On the TFT array substrate 1, a plurality of pixel electrodes 11 provided in a matrix, a plurality of data lines 35 arranged in the X direction, each extending in the Y direction, and a plurality of data lines 35 arranged in the Y direction. The scanning lines 31 each extend between the data lines 35 and the pixel electrodes 11 and the conductive state and the non-conductive state between the data lines 35 and the pixel electrodes 11 are scanned. A plurality of TFTs 30 each of which is controlled by using a scanning signal supplied via the line 31 are formed.
[0029]
Further, on the TFT array substrate 1, a precharge circuit 201 according to the present invention for supplying a precharge signal of a predetermined voltage level to each of the plurality of data lines 35 prior to the image signal, A sampling circuit 301 according to the present invention, which supplies a sample to each of the plurality of data lines 35, a data line driving circuit 101, and a scanning line driving circuit 104 are formed. Here, the data line drive circuit 101 includes a shift register circuit for image signals and a shift register circuit dedicated for precharge, which will be described later. Further, the sampling circuit 301 includes a plurality of TFTs 302 as a plurality of second switching means which are independently driven, while the precharge circuit 201 includes a plurality of first switching means which are independently driven. TFT 302 is included.
[0030]
The scanning line driving circuit 104 applies a scanning signal to the scanning lines 31 in a pulse-wise line-sequential manner at a predetermined timing based on a power supply voltage and a reference clock supplied from an external control circuit.
[0031]
On the other hand, the image signal shift register circuit in the data line driving circuit 101 adjusts the timing of applying the scanning signal by the scanning line driving circuit 104 based on a power supply voltage, a reference clock, and the like supplied from the external control circuit. For each of the image signal input lines VID1 to VID6 as one image signal supply line, a sampling circuit drive signal is supplied to the TFT 302 in the sampling circuit 301 for each data line 35 via the sampling circuit drive signal line 306.
[0032]
In parallel with this, prior to the timing at which the sampling circuit drive signal is output, the precharge dedicated shift register circuit in the data line drive circuit precharges each of the TFTs 202 constituting the precharge circuit 201 from the external control circuit. A precharge circuit drive signal supplied through the charge circuit drive signal line 206 is supplied to each TFT 202 via the precharge circuit drive signal line 206a.
[0033]
Next, the precharge circuit 201 includes a TFT 202 for each data line 35. The precharge signal line 204 is connected to the source electrode of the TFT 202, the precharge circuit drive signal line 206a is connected to the gate electrode of the TFT 202, and the data line 35 is connected to the drain electrode of the TFT 202. Then, power of a predetermined voltage required for writing the precharge signal is supplied from an external power supply via the precharge signal line 204, and the precharge signal is written to each data line 35 at a timing preceding the image signal. As described above, the precharge circuit drive signal is supplied from the precharge dedicated shift register circuit in the data line drive circuit 101 via the precharge circuit drive signal line 206a. At this time, the precharge circuit 201 preferably supplies the data line 35 with the precharge signal corresponding to pixel data of an intermediate gradation level.
[0034]
On the other hand, in the sampling circuit 301, the TFT 302 is provided for each data line 35, the image signal input lines VID1 to VID6 are read in contact with the source electrode of the TFT 302, and the sampling circuit drive signal line 306 is connected to the gate electrode of the TFT 302, respectively. Have been. Then, when six parallel image signals expanded into six phases are input via the image signal input lines VID1 to VID6, these image signals are sampled. When the sampling circuit drive signal is input from the image signal shift register in the data line drive circuit 101 via the sampling circuit drive signal line 306, the image signals sampled for each of the six image signal input lines VID1 to VID6 Is sequentially applied to the data lines 35 in groups of six adjacent data lines 35.
[0035]
At this time, the positional relationship between the precharge circuit 201 and the sampling circuit 301 on the TFT array substrate 1 is such that the precharge circuit 201 is formed adjacent to the data line drive circuit 101 as shown in FIG. Further, image signal input lines VID1 to VID6 are disposed adjacent to the precharge circuit 201, and a sampling circuit 301 is formed adjacent to the image signal input lines VID1 to VID6.
[0036]
That is, the sampling circuit 301 and the precharge circuit 201 are formed so as to sandwich the image signal input lines VID1 to VID6, and the sampling circuit 301 is formed at a position closer to the image display area with respect to the precharge circuit 201. (See FIG. 2).
[0037]
Here, the sampling circuit 301 and the precharge circuit 201 are housed in a light-shielding case when the liquid crystal panel is completed. Therefore, the TFT 202 and the semiconductor layer in the TFT 301 included in the sampling circuit 301 and the precharge circuit 201 are not irradiated with incident light or the like from the outside, and light generated by the incident light or the like in the semiconductor layer is not emitted. No current is generated and the TFT 202 or the TFT 302 does not malfunction.
[0038]
On the other hand, the data line driving circuit 101 and the scanning line driving circuit 104 are provided on a peripheral portion of the TFT array substrate 1 not facing the liquid crystal layer 50, as shown in FIGS.
[0039]
2 and 3, on the TFT array substrate 1, the image display area including a plurality of pixel electrodes 11 and having a size defined by the size thereof (that is, the alignment state of the liquid crystal layer 50 is actually determined). A seal member 52 made of a photocurable resin and surrounding the liquid crystal layer 50 by bonding the two substrates together around the area where an image is displayed by the change) is provided along the image display area. The sealing material 52 is an adhesive made of, for example, a photocurable resin or a thermosetting resin for bonding the TFT array substrate 1 and the opposing substrate 2 around the periphery thereof. Spacers are mixed.
[0040]
Next, as shown in FIG. 2, a data line driving circuit 101 and a mounting terminal 102 are provided along a lower side of the image display area in an area outside the seal material 52, and two left and right sides of the image display area are provided. A scanning line driving circuit 104 is provided along both sides of the image display area. Further, a plurality of wirings 105 are provided on the upper side of the image display area.
[0041]
In at least one of the corners of the opposing substrate 2, silver dots 106 made of a conductive material for establishing electric conduction between the TFT array substrate 1 and the opposing substrate 2 are provided. The opposite substrate 2 having substantially the same contour as the sealing material 52 is fixed to the TFT array base 1 by the sealing material 52.
[0042]
Here, the precharge circuit 201 and the sampling circuit 301 are basically AC driven circuits. Therefore, even if the precharge circuit 201 and the sampling circuit 301 are provided in the portion of the TFT array substrate 1 which faces the liquid crystal layer 50 surrounded by the sealing material 52 and sandwiched between the two substrates, The problem of deterioration of 50 does not occur.
[0043]
Further, since the precharge circuit 201 and the sampling circuit 301 are not formed on the portion of the TFT array substrate 1 facing the sealing material 52, the TFTs 202 and 302 constituting these circuits are destroyed by the spacer mixed in the sealing material 52. There is no fear of doing.
[0044]
(B)Configuration of precharge circuit and sampling circuit
Next, in the liquid crystal device 200 according to the first embodiment, specific configurations of the precharge circuit 201 and the sampling circuit according to the present invention will be described with reference to FIGS. 6 is an enlarged plan view of the precharge circuit 201 as viewed from the counter electrode 2 side, FIG. 7 is a cross-sectional view of the liquid crystal device 200 taken along the line BB ′ in FIG. 6, and FIG. FIG. 6 is a sectional view taken along line AA ′ of FIG.
[0045]
The TFT 202 in the precharge circuit 201 according to the first embodiment may be more specifically composed of an N-channel type TFT 202a as shown in FIG. 4A, or as shown in FIG. As described above, it may be composed of a P-channel type TFT 202b. Here, in FIG. 4 (1) or FIG. 4 (2), the precharge circuit drive signal input via the precharge circuit drive signal line 206a shown in FIG. 1 is applied to each TFT 202a or TFT 202b via the gate electrode. And a precharge signal also input via the precharge signal line 204 shown in FIG. 1 is input to each TFT 202a or TFT 202b via a source electrode.
[0046]
Correspondingly, the TFT 302 in the sampling circuit 301 of the first embodiment may be composed of an N-channel TFT 302a as shown in FIG. 5A, or as shown in FIG. And a P-channel type TFT 302b. Here, in FIG. 5 (1) or FIG. 5 (2), the six image signals input via the image signal input lines VIDn (VID1 to VID6) shown in FIG. And a sampling circuit drive signal also input from the data line drive circuit 101 shown in FIG. 1 via the sampling circuit drive signal line 306 is input to the TFT 302a or the TFT 302b as a gate voltage.
[0047]
First, the configurations of the precharge circuit 201 and the sampling circuit 301 according to the first embodiment will be described with reference to FIG. FIG. 6 shows a case where the TFT 202 is formed of one of an N-channel TFT and a P-channel TFT. In FIG. 6, an image signal is shown for simplification of description. There are three input lines.
[0048]
As shown in FIG. 6, the precharge circuit 201 and the sampling circuit 301 of the first embodiment are arranged on both sides of the image signal input lines VID1 to VID3, and the sampling circuit 301 is connected to the image signal input line. It is arranged on the image display area side when viewed from VID1 to VID3.
[0049]
At this time, the TFT 202 in the precharge circuit 201 has the precharge signal line 204 as a source electrode line, the precharge circuit drive signal line 206a as a gate electrode line, and the data line 35 as a drain electrode line.
[0050]
Each electrode line and each electrode region of each TFT 202 are interlayer-connected by a contact hole 38.
[0051]
On the other hand, the signal line 303 in which the TFT 302 in the sampling circuit 301 is connected to any one of the image signal input lines VID1 to VID3 is a source electrode line, the sampling circuit driving signal line 306 is a gate electrode line, and the data line 35 is configured as a drain electrode line.
[0052]
Each electrode line and each electrode region of each TFT 302 are interlayer-connected by a contact hole 38.
[0053]
Further, in order to commonly connect the drain electrode of the TFT 202 and the drain electrode of the TFT 302 by the gate line 35, a relay wiring 304 is formed in a layer different from the image signal input lines VID1 to VID3.
[0054]
Next, the cross-sectional configuration of the liquid crystal panel at the sampling circuit 301 will be further described with reference to FIG. In FIG. 7, the scale of each layer and each member is different in order to make each layer and each member have a size that can be recognized on the drawing. FIG. 7 also shows the alignment film 22 and the like formed so as to face the sampling circuit 301 with the liquid crystal layer 50 interposed therebetween.
[0055]
Note that the cross-sectional structure of the liquid crystal panel at the TFT 202 in the precharge circuit 201 is basically the same as the cross-sectional structure shown in FIG.
[0056]
As shown in FIG. 7, the TFT 302 in the sampling circuit 301 includes a TFT array substrate 1, a first interlayer insulating layer 41 laminated thereon, a semiconductor layer 32 such as p-Si (polysilicon), a gate insulating layer 33, Sampling circuit drive signal line 306 (gate electrode), precharge signal line 204 (source electrode), second interlayer insulating layer 42, data line 35 (drain electrode), third interlayer insulating layer 43, light shielding film 44, and alignment film 12 It has.
[0057]
In addition, at a position facing the TFT 302, a counter substrate 2 made of, for example, a glass substrate and the alignment film 22 laminated thereon are provided. Then, a liquid crystal 50 is sealed between the respective alignment films 12 and 22.
[0058]
Next, among these layers, the configuration of each layer except for the TFT 302 will be described in order.
[0059]
First, the light blocking film 44 formed on the TFT array substrate 1 prevents the TFT 302 from being irradiated with light from below in FIG. 7, thereby preventing photocurrent from being induced in the semiconductor layer 32 forming the TFT 302. . Note that the light-shielding film 44 is not required in a reflective liquid crystal panel.
[0060]
Next, the first interlayer insulating layer 41 serving as the basis of the TFT 302 is made of NSG, PSG (P₂O₅SiO containing₂), BSG (B₂O₃SiO containing₂), BPSG (P₂O₅And B₂O₃SiO containing₂), A silicon nitride film, a silicon oxide film, or the like. Here, by performing an annealing treatment at about 900 ° C. at the time of manufacturing the first interlayer insulating layer 41, it is possible to prevent contamination and planarize.
[0061]
The second interlayer insulating layer 42 and the third interlayer insulating layer 43 are each formed of a silicate glass film such as NSG, PSG, BSG, BPSG, etc., a silicon nitride film, a silicon oxide film, or the like having a thickness of about 5000 to 15000 °.
[0062]
Next, the alignment films 12 and 22 are made of an organic thin film such as a polyimide thin film. The alignment films 12 and 22 are formed, for example, by applying a polyimide-based coating solution and then performing a rubbing process in a predetermined direction so as to have a predetermined pretilt angle.
[0063]
The liquid crystal layer 50 is formed between the TFT array substrate 1 and the opposing substrate 2 by sealing the liquid crystal into a space surrounded by a sealing material 52 (see FIGS. 2 and 3) by vacuum suction or the like. You. The liquid crystal layer 50 is made of, for example, a liquid crystal in which one or several kinds of nematic liquid crystals are mixed.
[0064]
Next, the configuration of each layer of the TFT 302 will be described in order.
[0065]
As shown in FIG. 7, the TFT 302 includes a sampling circuit driving signal line 306 (gate electrode) and a channel forming region 37 included in the semiconductor layer 32 and in which a channel is formed by an electric field from the sampling circuit driving signal line 306. A gate insulating layer 33 that insulates the sampling circuit drive signal line 306 from the semiconductor layer 32; a source region 34 formed in the semiconductor layer 32; a data line 35 (drain electrode); a signal line 303; And a contact hole 38 for interlayer connection between the data line 35 and the drain region 36, and between the signal line 303 and the source region 34, respectively.
[0066]
Of these, the source region 34 and the drain region 36 have a predetermined concentration depending on whether a P-type channel formation region 37 or a p-type channel formation region 37 is formed in the semiconductor layer 32, as described later. It is formed by doping a p-type or p-type dopant.
[0067]
Here, the P-type channel TFT 302 has an advantage of a high operation speed, and is suitable as the sampling circuit 301.
[0068]
On the other hand, for example, after forming an a-Si (amorphous silicon) film on the first interlayer insulating layer 41 as a base, the semiconductor layer 32 is annealed to be solid-phase grown to a thickness of about 500 to 2000 °. It forms by doing. At this time, in the case of the n-channel type TFT 302, a dopant of a group V element such as Sb (antimony), As (arsenic), or P (phosphorus) is doped by ion implantation or the like. In the case of the p-channel TFT 302, a dopant of a subgroup element such as Al (aluminum), B (boron), Ga (gallium), and In (indium) is doped by an ion implantation method or the like.
[0069]
At this time, particularly when the TFT 302 is an n-channel TFT having an LDD (Lightly Doped Drain) structure, the TFT 302 is formed on the p-type semiconductor layer 32 and on the channel forming region 37 side of the source region 34 and the drain region 36, respectively. A lightly doped region is formed by doping an adjacent part with a group V element such as P, and another part is similarly doped with a group V element such as P to form a heavily doped region. Further, when a p-channel TFT is used, a source region 34 and a drain region 36 are formed in the P-type semiconductor layer 32 by using a dopant of a group III element such as B. When the LDD structure is used in this manner, an advantage that the short channel effect can be reduced can be obtained.
[0070]
Note that the TFT 302 may be an offset-structure TFT without forming a low-concentration drain region, or may be a self-aligned TFT using a gate electrode as a mask.
[0071]
On the other hand, the gate insulating layer 33 is obtained by thermally oxidizing the semiconductor layer 32 at a temperature of about 900 to 1300 ° C. to form a relatively thin thermal oxide film of about 300 to 1500 °.
[0072]
Further, the data line 35 (drain electrode) is formed by a photolithography process, an etching process, and the like after p-Si is deposited by a low-pressure CVD method or the like. At this time, it may be formed from a metal film such as Al or a metal silicide film.
[0073]
Further, the data line 35 (drain electrode) may be formed of a transparent conductive thin film such as an ITO film, like the pixel electrode 11.
[0074]
Further, it may be formed from a low-resistance metal such as Al or a metal silicide deposited to a thickness of about 1000 to 5000 ° by a sputtering process or the like.
[0075]
On the other hand, the contact holes 38 are formed by dry etching such as reactive etching and reactive ion beam etching.
[0076]
In general, when light enters the semiconductor layer 32 serving as the channel formation region 37, a photocurrent is generated due to the photoelectric conversion effect of p-Si, and the transistor characteristics of the TFT 302 deteriorate. However, in the first embodiment, Since the TFT 302 and the TFT 202 are housed in a light-shielding case, external light can be prevented from entering at least the channel region of the semiconductor layer 32.
[0077]
Additionally or alternatively, the data line 35 (drain electrode) is formed from an opaque metal thin film such as Al so as to cover the channel formation region 37 from above, and the light incident on the semiconductor layer 32 (ie, 7 may be configured to prevent the incidence of light from above.
[0078]
In the first embodiment, since the TFTs 302 and 202 are p-Si type TFTs, the sampling circuit 201, the precharge circuit 301, the data line driving circuit 101, and the scanning circuit are formed in the same thin film forming process when forming the TFTs 302 and 202. A peripheral circuit composed of the same p-Si TFT type TFT such as the line drive circuit 104 can be formed, which is advantageous in manufacturing.
[0079]
Further, the data line driving circuit 101 and the scanning line driving circuit 104 are formed on the periphery of the TFT array substrate 1 by a plurality of complementary TFTs composed of, for example, an n-channel p-Si TFT and a p-channel p-Si TFT. Formed in parts.
[0080]
Further, although not shown in FIG. 7, for example, a TN (twisted nematic) mode, STN ( Depending on the operation mode such as Super TN) mode, D-STN (Double-STN) mode, and normally white mode / normally black mode, the polarizing film, retardation film, polarizing plate, etc. Be placed.
[0081]
Next, a cross-sectional structure taken along line A-A 'of the portion where the relay wiring 304 shown in FIG. 6 is formed will be described with reference to FIG.
[0082]
The relay wiring 304 formed for connecting the data line 35 as the drain electrode of the TFT 302 and the data line 35 as the drain electrode of the TFT 202 while maintaining insulation between the image signal input lines VID1 to VID3 is, for example, As shown in FIG. 8A, it can be formed in the same layer as the layer where the scanning line 31 is formed between the first interlayer insulating film 41 and the second interlayer insulating film 42. At this time, the interlayer connection with each data line 35 is formed by the contact hole 38.
[0083]
In addition, as shown in FIG. 8B, the light shielding film 44 between the TFT array substrate 1 and the first interlayer insulating layer 41 is formed on the same layer as the light shielding film 44. The lines 35 can be connected to each other by using the contact holes 38.
[0084]
Further, in order to lower the resistance, as shown in FIG. 8C, the relay wiring 304 is formed on the same layer as the layer on which the light shielding film 44 is formed between the TFT array substrate 1 and the first interlayer insulating layer 41. And a relay wiring 304 ′ is formed on the same layer as the layer on which the scanning line 31 is formed between the first interlayer insulating film 41 and the second interlayer insulating film 42. The data lines 35 may be connected to each other through the contact holes 38, and the relay wirings 304 and 304 'may be connected to each other through the contact holes 38'.
[0085]
Furthermore, in order to similarly lower the resistance, as shown in FIG. 8D, the same layer as the layer where the scanning line 31 is formed between the first interlayer insulating film 41 and the second interlayer insulating layer 42 is used. A relay wiring 304 is formed in the layer, and a relay wiring 304 ′ is formed on the upper surface of the third interlayer insulating film 43 in FIG. 8D, and the relay wiring 304 ′ and each data line 35 are contact holes 38 respectively. ′, The respective data lines 35 and the relay wiring 304 may be connected via the contact holes 38. In this case, it is necessary to further form a fourth interlayer insulating film 45 on the upper surfaces of the relay wiring 304 'and the third interlayer insulating film 43 in FIG.
[0086]
(C)Operation of liquid crystal device
Next, the operation of the liquid crystal device 200 configured as described above will be described with reference to FIG.
[0087]
First, the scanning line driving circuit 104 applies a scanning signal to the scanning line 31 in a pulsed manner at predetermined timing in a line-sequential manner.
[0088]
In parallel with this, when receiving six parallel image signals developed in six phases from the six image signal input lines VID1 to VID6, the sampling circuit 301 samples these image signals.
[0089]
On the other hand, the data line driving circuit 101 supplies a sampling circuit driving signal for each of the six image signal input lines VID1 to VID6 for each data line in accordance with the timing at which the scanning line driving circuit 104 applies the gate voltage. The TFT 302 of the sampling circuit 301 is turned on. Thus, the image signals sampled by the sampling circuit 301 are sequentially applied to the six adjacent data lines 35. That is, the data line driving circuit 101 and the sampling circuit 301 expand the six parallel image signals, which are input from the image signal input lines VID1 to VID6 and are expanded into six phases, to be supplied to the data lines 35.
[0090]
On the other hand, the precharge circuit 201 supplies a precharge signal to each data line 35 at a timing preceding each image signal. More specifically, the precharge circuit 201 receives a power supply for writing a precharge signal to the data line 35 from the precharge signal line 204 and receives a precharge signal input through the precharge circuit drive signal edge 206. The TFT 202 is turned on in response to the circuit drive signal, and a precharge signal is written to the data line 35.
[0091]
Then, in the TFT 30 to which both the scanning signal and the image signal are applied, a voltage is applied to the pixel electrode 11 via the source region, the channel forming region, and the drain region. Thereafter, the voltage of the pixel electrode 11 is maintained by a storage capacitor (not shown) for a time longer than the time when the source voltage is applied, for example, by three orders of magnitude.
[0092]
In the first embodiment, in order to drive the liquid crystal by AC, the voltage polarity of the source voltage on the data line 35 is inverted every predetermined period such as one field or one frame. Before being supplied to the TFT 30, a precharge signal preferably corresponding to a pixel signal of an intermediate gradation level is supplied to each data line 35, so that a load at the time of writing an image signal is reduced. The potential level of the line 35 is stable irrespective of the previously applied voltage level. Therefore, the current image signal can be supplied to each data line 35 at a stable potential.
[0093]
As described above, when a voltage is applied to the pixel electrode 11, the alignment state of the liquid crystal in a portion of the liquid crystal layer 50 between the pixel electrode 11 and the common electrode 21 changes. In accordance with the applied voltage, the incident light cannot pass through the liquid crystal portion. In the normally black mode, the incident light can pass through the liquid crystal portion according to the applied voltage. The device 200 emits light having a contrast corresponding to the image signal.
[0094]
As described above, according to the liquid crystal device 200 of the first embodiment, in the positional relationship between the precharge circuit 201 and the sampling circuit 301, the sampling circuit 301 is closer to the image display area. The resistance between the circuit and the circuit can be reduced, and the waveform of an image signal to be supplied to the pixel electrode 11 can be prevented from being deformed.
[0095]
Further, a plurality of image signal input lines VID1 to VID6 for applying the phase-expanded image signals are formed on the TFT array substrate 1 between the region where the precharge circuit 201 is formed and the region where the sampling circuit 301 is formed. Therefore, the path of the image signal from the image signal input lines VID1 to VID6 to the pixel electrode 11 via the sampling circuit 301 can be shortened and the resistance can be reduced.
[0096]
Further, since the TFT 202 or the TFT 302 is one of a P-channel TFT and an N-channel TFT, an image signal or a precharge signal can be supplied to the data line at high speed.
[0097]
Furthermore, since the image signal expanded in multi-phase by the sampling circuit 301 is sampled and supplied as an image signal to the data line 35 after the multi-phase expansion, a high-frequency image signal is supplied to each data line 35 at a predetermined timing. And can be supplied stably in synchronization with the scanning signal.
[0098]
Further, since the precharge signal is supplied from the precharge circuit 201 prior to the image signal, the contrast ratio can be improved, the potential level of the data line 35 can be stabilized, and line unevenness on the display screen can be reduced. Thus, an image having a high crystallinity can be displayed in the image display area of the liquid crystal device 200.
[0099]
Further, since the liquid crystal device 200 including the above-described precharge circuit 201 is applied to a color liquid crystal projector, three liquid crystal devices 200 are respectively used as light valves for RGB, and each panel is provided with RGB color separation valves. The light of each color decomposed via the dichroic mirror is respectively incident as incident light. Therefore, in each embodiment, no color filter is provided on the opposing substrate 2.
[0100]
However, in the liquid crystal device 200 as well, an RGB color filter may be formed on the opposing substrate 2 in a predetermined region facing the pixel electrode 11 together with its protective film. In this way, the liquid crystal device 200 of the first embodiment can be applied to a color liquid crystal device such as a direct-view or reflection type color liquid crystal television other than the liquid crystal projector.
[0101]
In the first embodiment, the TFT 202 of the precharge circuit 201 or the TFT 302 of the sampling circuit 301 is described as a normal staggered or coplanar p-Si TFT. However, an inverted staggered TFT or a-Si TFT is used. The first embodiment is also effective for other types of TFTs such as TFTs.
[0102]
Further, in the liquid crystal device 200, the liquid crystal layer 50 is composed of a nematic liquid crystal as an example. However, if a polymer dispersed liquid crystal in which the liquid crystal is dispersed as fine particles in a polymer is used, the alignment films 12 and 22 and This eliminates the need for a polarizing film, a polarizing plate, and the like, and provides advantages of higher brightness and lower power consumption of the liquid crystal device due to an increase in light use efficiency.
[0103]
Furthermore, if the pixel electrode 11 is made of a metal film having a high reflectance such as Al, when the liquid crystal device 200 is applied to a reflection type liquid crystal device, SH ( Super homeotropic) type liquid crystal can be used.
[0104]
Further, a micro lens may be formed on the counter substrate 20 so as to correspond to one pixel. By doing so, the light collection efficiency of incident light is improved, and a brighter liquid crystal panel can be realized.
[0105]
Furthermore, in the liquid crystal device 200, the common electrode 21 is provided on the side of the counter substrate 2 so as to apply a vertical electric field (vertical electric field) to the liquid crystal layer 50. Each of the pixel electrodes 11 is composed of a pair of electrodes for generating a horizontal electric field so as to apply an electric field (that is, without providing an electrode for generating a vertical electric field on the side of the counter substrate 2, the side of the TFT array substrate 1). It is also possible to provide an electrode for generating a lateral electric field at the same time. The use of the horizontal electric field is more advantageous in widening the viewing angle than the case of using the vertical electric field.
[0106]
(II)Second embodiment
Next, a second embodiment which is another embodiment according to the present invention will be described with reference to FIGS. 9 or 10, the same members as those in FIG. 1 or FIG. 6 are denoted by the same reference numerals, and the detailed description is omitted. Further, in the second embodiment, the configuration of the entire liquid crystal device 200 is the same as that of the first embodiment, and the only difference is the configuration of a precharge circuit and a sampling circuit described below.
[0107]
In the first embodiment described above, each TFT 302 in the sampling circuit 301 is connected to one sampling circuit drive signal line 306 from the data line drive circuit 101, and the TFT 202 in the precharge circuit 201 is also connected. The data line drive circuit 101 is configured to connect one precharge circuit drive signal line 206a and one precharge signal line 204 respectively.
[0108]
On the other hand, in the precharge circuit and the sampling circuit of the second embodiment, by arranging a plurality of signal lines for supplying signals to the TFTs included in the precharge circuit and the sampling circuit on the TFT array substrate 1, The area occupied by the precharge circuit is reduced.
[0109]
That is, as shown in FIG. 9, in the liquid crystal device 200 'of the second embodiment, as in the first embodiment, the sampling circuit 301 and the precharge circuit 201' sandwich the image signal input lines VID1 to VID6. Are formed, and the sampling circuit 301 is formed at a position closer to the image display area with respect to the precharge circuit 201 ′.
[0110]
The image signal shift register circuit includes a data line drive circuit 101 including the same image signal shift register circuit and the precharge dedicated shift register circuit as in the first embodiment. One sampling circuit drive signal line 306 is branched and connected to the gate electrode of each TFT 302. Then, according to this configuration, the six TFTs 302 are simultaneously opened and driven.
[0111]
Further, for the six TFTs 202, one precharge circuit drive signal line 206a from the precharge dedicated shift register is branched and connected to the gate electrode of each TFT 202. Also, with this configuration, the six TFTs 202 are simultaneously opened and driven.
[0112]
Further, the corresponding image signal input lines VID1 to VID6 are connected to the source electrodes of the respective TFTs 302 via signal lines 303, respectively, and are configured to supply the image signals developed in phases.
[0113]
Furthermore, each TFT 202 has a configuration in which the source electrodes of two adjacent TFTs 202 are overlapped and share one precharge signal line 204a, which will be described later.
[0114]
The drain electrode of the TFT 202 corresponding to the drain electrode of one TFT 302 is connected to one data line 35. At this time, the portion of the data line 35 that planarly overlaps the image signal input lines VID1 to VID6 is a relay wiring 304 or 304 'as illustrated in FIG.
[0115]
Next, a specific pattern layout of the precharge circuit and the sampling circuit according to the second embodiment will be described with reference to FIG.
[0116]
As shown in FIG. 10, in the precharge circuit 201 ′ of the second embodiment, one adjacent source electrode is shared by two adjacent TFTs 202, and one precharge signal line 204a is connected to the one source electrode. It is connected.
[0117]
Further, one precharge circuit drive signal line 206a from the data line drive circuit 101 'is branched and connected to the gate electrodes of the six TFTs 202 adjacent to each other.
[0118]
Further, for each of the TFTs 302 in the sampling circuit 301, one sampling circuit drive signal line 306 from the data line drive circuit 101 'is branched and connected to each of the gate electrodes of the six TFTs 302.
[0119]
At this time, each electrode line and each electrode region of each TFT 302 or TFT 202 are interlayer-connected by a contact hole 38.
[0120]
According to the configuration of the sampling circuit 301 and the precharge circuit 201 'in the liquid crystal device 200' of the second embodiment described above, in addition to the effect of the configuration of the liquid crystal device 200 of the first embodiment, the sampling circuit 301 and the precharge circuit 201 ' The area on the TFT array substrate 1 occupied by the circuit 201 'can be reduced.
[0121]
(Electronics)
Next, an embodiment of an electronic apparatus including the liquid crystal device 200 described in detail above will be described with reference to FIGS.
[0122]
First, FIG. 17 shows a schematic configuration of an electronic apparatus including the liquid crystal device 200 as described above.
[0123]
In FIG. 17, an electronic device includes a display information output source 1000, a display driving circuit 1004 including the above-described external display information processing circuit 1002, the above-described scanning line driving circuit 104 and the data line driving circuit 101, a liquid crystal panel 10, a clock generation circuit. 1008 and a power supply circuit 1010. The display information output source 1000 includes a ROM (Read Only Memory), a RAM (Random Access Memory), a memory such as an optical disk device, a tuning circuit for tuning and outputting a television signal, and the like. Display information such as an image signal in a predetermined format is output to the display information processing circuit 1002 based on the clock signal. The display information processing circuit 1002 includes various known processing circuits such as an amplification / polarity inversion circuit, a phase expansion circuit, a rotation circuit, a gamma correction circuit, and a clamp circuit. Digital signals are sequentially generated from the input display information based on the display information and output to the display drive circuit 1004 together with the clock signal CLK. The display driving circuit 1004 drives the liquid crystal panel 10 by the scanning line driving circuit 104 and the data line driving circuit 101 by the driving method described above. The power supply circuit 1010 supplies a predetermined power to each of the above-described circuits. Note that the display drive circuit 1004 may be mounted on the TFT array substrate constituting the liquid crystal panel 10, and in addition, the display information processing circuit 1002 may be mounted.
[0124]
As the electronic apparatus having such a configuration, a liquid crystal projector shown in FIG. 18, a multimedia-compatible personal computer (PC) and an engineering workstation (EWS) shown in FIG. 19, or a mobile phone, a word processor, a television, a viewfinder type or Examples include a monitor direct-view video table recorder, an electronic organizer, an electronic desk calculator, a car navigation device, a POS terminal, and a device having a touch panel.
[0125]
Next, FIGS. 18 to 20 show specific examples of the electronic device configured as described above. In FIG. 18, a liquid crystal projector 1100, which is an example of an electronic device, is a projection type liquid crystal projector, and includes a light source 1110, dichroic mirrors 1113, 1114, reflection mirrors 1115, 1116, 1117, an incident lens 1118, a relay lens 1119, It comprises an emission lens 1120, liquid crystal light valves 1122, 1123, 1124, a cross dichroic prism 1125, and a projection lens 1126. The liquid crystal light valves 1122, 1123, and 1124 are prepared by preparing three liquid crystal modules each including the liquid crystal panel 10 in which the above-described drive circuit 1004 is mounted on a TFT array substrate, and using each of them as a liquid crystal light valve. The light source 1110 includes a lamp 1111 such as a metal halide and a reflector 1112 that reflects light from the lamp 1111.
[0126]
In the liquid crystal projector 1100 configured as described above, the dichroic mirror 1113 for reflecting blue light and green light transmits red light of the white light flux from the light source 1110 and reflects blue light and green light. . The transmitted red light is reflected by the reflection mirror 1117 and is incident on the liquid crystal light valve 1122 for red light. On the other hand, among the color lights reflected by the dichroic mirror 1113, green light is reflected by the dichroic mirror 1114 that reflects green light, and is incident on the liquid crystal light valve 1123 for green light. The blue light also passes through the second dichroic mirror 1114. For blue light, in order to prevent light loss due to a long optical path, light guiding means 1121 composed of a relay lens system including an entrance lens 1118, a relay lens 1119, and an exit lens 1120 is provided. The light enters the liquid crystal light valve for light 1124. The three color lights modulated by the respective light valves enter the cross dichroic prism 1125. This prism has four right-angle prisms bonded together, and a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light are formed in a cross shape on the inner surface. The three color lights are combined by these dielectric multilayer films to form light representing a color image. The synthesized light is projected on a screen 1127 by a projection lens 1126 which is a projection optical system, and an image is enlarged and displayed.
[0127]
In FIG. 19, a laptop personal computer 1200 as another example of the electronic apparatus includes a liquid crystal display 1206 in which the above-described liquid crystal panel 10 is provided in a top cover case, a CPU, a memory, a modem, and the like. And a main body 1204 in which the main body 1202 is incorporated.
[0128]
Further, as shown in FIG. 20, a liquid crystal device is provided between the two transparent substrates 1304a and 1304b, and the above-described driving circuit 1004 is mounted on a TFT array substrate. One of the two transparent substrates 1304a and 1304b constituting the substrate 1304 is connected to a TCP (Tape Carrier Package) 1320 in which an IC chip 1324 is mounted on a polyimide tape 1322 on which a metal conductive film is formed, for electronic equipment. It can be produced, sold, and used as a liquid crystal device, which is a component of the system.
[0129]
As described above, in addition to the electronic devices described with reference to FIGS. 18 to 20, a liquid crystal television, a viewfinder type or a monitor direct-view type video tape recorder, a car navigation device, an electronic organizer, a calculator, a word processor, a workstation, a mobile phone A telephone, a videophone, a POS terminal, a device having a touch panel, and the like are examples of the electronic device shown in FIG.
[0130]
Note that the present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention. For example, the present invention is not limited to being applied to the driving of the various liquid crystal panels described above, but is also applicable to electroluminescence and plasma display devices.
[0131]
According to the present embodiment, various electronic devices including the liquid crystal device 200 which is small and has a sufficient precharge function to remarkably reduce a load on a signal source of an image signal, and is capable of displaying images stably. realizable.
[0132]
【The invention's effect】
As described above, according to the present invention, in the positional relationship between the second switching means and the third switching means, the second switching means for supplying the image signal is closer to the image display area. The resistance between the second switching means and the second switching means can be reduced, and a sharp image can be obtained by preventing the waveform of an image signal to be supplied to the pixel electrode from being deformed.
[0133]
Further, since the image signal application line is disposed on the substrate between the region where the second switching unit is formed and the region where the third switching unit is formed, the second switching unit is connected from the image signal application line. Thus, a clear image can be obtained by shortening the path of the image signal up to the pixel electrode via the gate electrode and lowering the resistance.
[Brief description of the drawings]
FIG. 1 is a block diagram of various wirings, peripheral circuits, and the like formed on a TFT array substrate according to a first embodiment.
FIG. 2 is a plan view illustrating an overall configuration of a liquid crystal device.
FIG. 3 is a cross-sectional view illustrating an entire configuration of a liquid crystal device.
FIGS. 4A and 4B are circuit diagrams of TFTs forming a precharge circuit provided in a liquid crystal device. FIG. 4A is a circuit diagram of an n-channel TFT, and FIG. 4B is a circuit diagram of a p-channel TFT.
FIGS. 5A and 5B are circuit diagrams of TFTs constituting a sampling circuit provided in a liquid crystal device. FIG. 5A is a circuit diagram of an n-channel TFT, and FIG. 5B is a circuit diagram of a p-channel TFT.
FIG. 6 is a plan view illustrating a configuration of a precharge circuit according to the first embodiment.
FIG. 7 is a cross-sectional view illustrating a configuration of a precharge circuit according to the first embodiment.
FIGS. 8A and 8B are cross-sectional views illustrating a configuration of the relay wiring according to the first embodiment, wherein FIG. 8A is a cross-sectional view illustrating a first example of the layout of the relay wiring, and FIG. It is sectional drawing which shows an example, (3) is sectional drawing which shows the 3rd example of arrangement | positioning of a relay wiring, (4) is sectional drawing which shows 4th example of arrangement | positioning of a relay wiring.
FIG. 9 is a block diagram of various wirings, peripheral circuits, and the like formed on a TFT array substrate according to a second embodiment.
FIG. 10 is a plan view illustrating a configuration of a precharge circuit according to a second embodiment.
FIG. 11 is a block diagram illustrating a schematic configuration of an electronic device.
FIG. 12 is a cross-sectional view illustrating a configuration of a liquid crystal projector as an example of an electronic apparatus.
FIG. 13 is a front view illustrating an appearance of a personal computer as an example of an electronic apparatus.
FIG. 14 is an exploded perspective view illustrating a configuration of a pager as an example of an electronic apparatus.
FIG. 15 is a perspective view illustrating an appearance of a liquid crystal device using TCP as an example of an electronic apparatus.
[Explanation of symbols]
1: TFT array substrate
2: Counter substrate
11 ... pixel electrode
12. Alignment film
21 ... Common electrode
22 ... Orientation film
30, 202, 202a, 202b, 302, 302a, 302b ... TFT
31 ... Scanning line (gate electrode)
32 ... Semiconductor layer
33 ... Gate insulating layer
34 ... Source area
35 ... data line (source electrode)
36 ... Drain region
38, 38 '... contact hole
41: first interlayer insulating layer
42 ... second interlayer insulating layer
43 ... third interlayer insulating layer
45 ... Fourth interlayer insulating layer
50 ... Liquid crystal layer
52 ... Seal material
101, 101 '... data line driving circuit
102 mounting terminals
104 ... scanning line drive circuit
200, 200 ': liquid crystal device
201, 201 '... precharge circuit
204, 204a... Precharge signal lines
206, 206a... Precharge circuit drive signal lines
301 ... Sampling circuit
304, 304 '... relay wiring
306 ... Sampling circuit drive signal line

Claims (8)

A plurality of pixel electrodes, a plurality of data lines to which an image signal is supplied, a plurality of scanning lines to which a scanning signal is supplied, and the data line and the data line interposed between the data line and the pixel electrode, respectively. An electro-optical device comprising: a first switching unit that controls a conduction state and a non-conduction state between pixel electrodes based on a scanning signal supplied to the scanning line;
A sampling circuit having second switching means for sampling the image signal from an image signal line based on a sampling circuit drive signal and supplying the image signal to the data line;
A precharge circuit having third switching means for supplying a precharge signal from the precharge signal line to the data line based on a precharge circuit drive signal prior to a sampling period for supplying the image signal to the data line. Equipped,
An electro-optical device, wherein the sampling circuit is disposed between an image display area in which the pixel electrode is formed and the precharge circuit. The third switching means is a thin film transistor, a supply line extending from the precharge signal line is electrically connected to a source electrode of the thin film transistor, and the data line is electrically connected to a drain electrode of the thin film transistor. The electro-optical device according to claim 1, wherein the device is connected. The second switching means is a thin film transistor, a relay line extending from the image signal line is electrically connected to a source electrode of the thin film transistor, and the data line is electrically connected to a drain electrode of the thin film transistor. The electro-optical device according to claim 1, wherein: The third switching means includes a plurality of thin film transistors provided respectively corresponding to the plurality of data lines, the precharge signal line is connected to a source electrode of each of the plurality of thin film transistors, and the plurality of thin film transistors The electro-optical device according to claim 1, wherein a precharge circuit drive signal line for supplying the precharge circuit drive signal from a data line drive circuit is connected to the gate electrode. The second switching means includes a plurality of thin film transistors provided respectively corresponding to the plurality of data lines, and a gate electrode of each of the plurality of thin film transistors extends in a direction in which the gate electrode of the thin film transistor of the third switching means extends. 5. The electro-optical device according to claim 4, wherein a sampling circuit drive signal line for supplying the sampling drive signal from the data line drive circuit is connected to a gate electrode of the thin film transistor of the second switching means. apparatus. It said second switching means comprises a plurality of thin film transistors which are provided respectively corresponding to the plurality of data lines, each of said plurality of thin film transistors from the data line driving circuit for each number of the image signal lines layer deployed the electro-optical device according to claim 1, wherein the supplying the sampled drive signals at the same time. Said third switching means comprises a plurality of thin film transistors which are provided respectively corresponding to the plurality of data lines, wherein the data line driving circuit for each number of the image signal lines of the plurality of the thin film transistors which are layers expanded 7. The electro-optical device according to claim 6, wherein a precharge circuit drive signal line for supplying a precharge circuit drive signal is branched and connected. An electronic apparatus comprising the electro-optical device according to claim 1.

Images