JP3900714B2 - Electro-optical device and electronic apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention belongs to the technical field of an electro-optical device of an active matrix driving system by driving a thin film transistor (hereinafter referred to as TFT as appropriate) and an electronic apparatus using the same, and in particular, a data line driving circuit provided on a TFT array substrate Thus, the present invention belongs to the technical field of an electro-optical device of a type that drives a data line at a high frequency based on a clock signal and an electronic device using the same.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in an electro-optical device such as a TFT-driven active matrix driving type liquid crystal device, a large number of scanning electrodes and data lines arranged in the vertical and horizontal directions and a large number of pixel electrodes corresponding to their intersections are provided on the TFT array substrate. It is provided above. In addition to these, a data signal supplying means for supplying a data signal to the data line including a data line driving circuit, a sampling circuit, etc., and a scanning signal supplying means for supplying a scanning signal to the scanning line including a scanning line driving circuit and the like May be provided on such a TFT array substrate.
[0003]
In this case, the data signal supply means includes a data line side reference clock that is a reference for the supply timing of the data signal, an image signal that corresponds to the content of the image to be displayed and is the basis of the data signal, a positive or negative constant. A potential power supply or the like is supplied via an external input terminal and wiring provided on the TFT array substrate. On the other hand, the scanning signal supply means includes a scanning line side reference clock, a positive or negative constant potential power source, which serves as a reference for the scanning signal supply timing, via an external input terminal and wiring also provided on the TFT array substrate. Supplied. In the scanning signal supply means, for example, a scanning signal is supplied to the scanning lines line-sequentially at a timing based on the scanning line side reference clock by a scanning line driving circuit. In response to this, in the data signal supply means, for example, the data line driving circuit sequentially drives the sampling circuit that samples the input image signal at the timing based on the data line side reference clock, and the data signal is output from the sampling circuit. Supplied to the data line. As a result, each TFT gate-connected to the scanning line is turned on in response to the supply of the scanning signal, and the data signal is supplied to the pixel electrode through the TFT to display an image in each pixel.
[0004]
In recent years, in particular, in a liquid crystal device for a liquid crystal projector or the like, a serial image signal with a very high frequency has been input as the resolution of a display image is increased. In order to cope with this, in particular, the frequency of the data line side reference clock supplied to the data signal supply means is also made very high.
[0005]
[Problems to be solved by the invention]
However, under the recent demand for high-quality display images, the generation of high-frequency clock noise due to such a high reference clock frequency cannot be ignored.
[0006]
That is, for example, in a configuration in which the sampling circuit is driven by supplying a data line side reference clock having a relatively low frequency to the data line driving circuit, if the frequency of the clock signal is increased as it is, an image input to the sampling circuit High-frequency clock noise occurs in the signal or in the data signal output from the sampling circuit, and the data signal to be supplied to the data line is deteriorated. When such a deteriorated data signal is supplied, the image displayed by each pixel electrode also deteriorates.
[0007]
The present invention has been made in view of the above-described problems, and can reduce the occurrence of high-frequency clock noise in an input image signal or a data signal generated based on the input image signal, thereby enabling high-quality image display. An object is to provide an electro-optical device and an electronic apparatus including the electro-optical device.
[0008]
[Means for Solving the Problems]
In order to solve the above problems, the electro-optical device of the present invention supports a plurality of scanning lines on the substrate, a plurality of data lines intersecting the plurality of scanning lines, and a crossing of the plurality of scanning lines and the data lines. And an image display area including a plurality of switching elements provided in correspondence with the plurality of switching elements and an image for supplying an image signal input from the first external input terminal A signal line; data signal supply means for supplying the image signal supplied to the image signal line as a data signal to the plurality of data lines based on a clock signal; and the clock signal input from a second external input terminal. A clock signal line to be supplied to the data signal supply means, and the image display area and an area where the image signal line is wired are disposed so as to surround the image signal line. Together electrically shielded from, characterized in that a conductive line for supplying power to the constant potential.
[0009]
According to this electro-optical device, the image signal input from the first external input terminal is supplied to the data signal supply means via the image signal line wired on the substrate. In parallel with this, the clock signal input from the second external input terminal is supplied to the data signal supply means via the clock signal line wired on the substrate. Then, the data signal corresponding to the image signal is supplied to the plurality of data lines based on the clock signal by the data signal supply means including the data line driving circuit, the sampling circuit, etc. provided on the substrate. The Here, in particular, the image signal line is electrically shielded from the clock signal line by a constant potential conductive line wired on the substrate. Therefore, even when the frequency of the clock signal is high, the jumping in of high frequency clock noise from the clock signal line to the image signal line can be reduced.
[0010]
On the other hand, a scanning signal is supplied to the switching element via the scanning line by scanning signal supply means including a scanning line driving circuit or the like formed on the substrate or connected to the substrate. In parallel with this, the data signal corresponding to the image signal in which the high-frequency clock noise is reduced as described above is supplied to the switching element via the data line, and is further supplied by the data signal supplied via the switching element. The voltage applied to the pixel electrode changes, and the liquid crystal facing the pixel electrode is driven. As a result of the above, even when a high-resolution serial image signal is input with a high-resolution image to be displayed, a high-frequency clock signal is used and the image quality is improved by the generation of high-frequency clock noise. Little or no deterioration occurs, and high-quality image display is possible.
[0011]
In the electro-optical device according to the aspect of the invention, it is preferable that the conductive line includes a portion including a constant potential line that supplies a constant potential power source to the data signal supply unit.
[0012]
According to this electro-optical device, the conductive line includes a portion composed of a constant potential line for supplying a constant potential power to the data signal supply means, so that it can be rephrased by sharing the external input terminal and the wiring itself. For example, by extending the constant potential line to form a conductive line, the configuration can be simplified and the space can be saved. In particular, it is extremely easy to set the conductive line to a constant potential.
[0013]
Further, the constant potential line of the electro-optical device according to the present invention includes first and second constant potential lines that supply power of different constant potentials to the data signal supply unit, and is configured by the first constant potential line. The conductive line portion may surround the image signal line on the substrate, and the conductive line portion formed of the second constant potential line may surround the clock signal line on the substrate.
[0014]
According to this electro-optical device, the image signal line is surrounded on the substrate by the conductive line portion formed of, for example, a first constant potential line for supplying a negative power supply having a ground potential. The clock signal line is surrounded on the substrate by a conductive line portion made up of a second constant potential line for supplying positive power, for example. Therefore, the image signal line can be double shielded from the clock signal line on the substrate.
[0015]
The data signal supply means of the electro-optical device of the present invention includes a sampling circuit that samples the image signal, and data that drives the sampling circuit based on the clock signal by receiving power from the constant potential line. It is preferable that the image signal line and the clock signal line are routed from opposite directions to the data line driving circuit on the substrate.
[0016]
According to this electro-optical device, the image signal is sampled by the sampling circuit in the scanning signal supply means. Then, the sampling circuit is driven based on the clock signal by the data line driving circuit that receives power supply from the constant potential line, and the sampled image signal is supplied to the data line as the data signal. Here, in particular, the image signal line and the clock signal line are routed from the opposite direction with respect to the data line driving circuit on the substrate, but generally electromagnetic waves are reduced depending on the distance and the presence of an obstacle, The electromagnetic wave applied from the clock signal line to the image signal line decreases according to the distance between the two signal lines and according to the presence of the data line driving circuit. Accordingly, even when the frequency of the clock signal is high, it is possible to further reduce high-frequency clock noise jumping from the clock signal line to the image signal line.
[0017]
In addition, the first and second external input terminals of the electro-optical device of the present invention are arranged at a predetermined interval from each other in the peripheral portion of the substrate, and are between the first and second external input terminals. It is preferable that a third external input terminal for inputting the constant potential power supply to the constant potential line is disposed.
[0018]
According to this electro-optical device, the first and second external input terminals are arranged at a predetermined distance from each other in the peripheral portion of the substrate with the third external input terminal interposed therebetween, preferably, the substrate In the region where the external input terminal can be formed in the peripheral portion of each other, they are arranged as far as possible from each other. Therefore, for example, compared with the case where the image signal line and the clock signal line are arranged adjacent to each other, the jump of high-frequency clock noise from the clock signal line to the image signal line can be reduced.
[0019]
In the electro-optical device according to the aspect of the invention, it is preferable that the conductive lines extend so as to surround the image display area defined by the plurality of pixel electrodes and the plurality of data lines on the substrate.
[0020]
According to this electro-optical device, the image display area and the plurality of data lines are surrounded on the substrate by the conductive lines, and therefore the image display area and the plurality of data lines are also shielded from the clock signal line. become. Therefore, it is possible to reduce the occurrence of high-frequency clock noise in the data signal output from the data signal supply means, the data signal reaching the switching element or the pixel electrode, and the like.
[0021]
In the electro-optical device according to the aspect of the invention, a counter substrate is provided to face the substrate, and the light-shielding property is formed on at least one of the substrate and the counter substrate along the outline of the image display region. A frame may be further provided, and the conductive wire may include a portion provided on the substrate along the frame at a position facing the frame.
[0022]
According to this electro-optical device, since the conductive lines are provided under the frame of the substrate, space saving on the TFT array substrate can be achieved. For example, the scanning line driving circuit and the data line driving circuit are arranged on the first substrate. The peripheral area of the electro-optical device can be formed with a margin, and the effective display area in the electro-optical device is hardly reduced or not at all due to the formation of the conductive line.
[0023]
In addition, it is preferable that the conductive line and the data line of the electro-optical device of the present invention are formed from the same low-resistance metal material.
[0024]
According to this electro-optical device, since the conductive line is made of the same low-resistance metal material as the data line, such as Al (aluminum), the conductive line is long even if the lead-out area of the conductive line is long. The resistance is sufficiently low for practical use. That is, without lowering the shielding effect due to the increase in resistance, for example, the conductive wires are long and zigzag by sewing gaps in other wirings and circuits, or the conductive wires are extended over a wide area including the image display area. Since wiring becomes possible, the effect of the shield as a whole can be further enhanced with a relatively simple configuration. Furthermore, in the manufacturing process of the electro-optical device, the conductive line and the data line can be formed from the same low-resistance metal material in the same process. That is, an increase in the manufacturing process due to the formation of the conductive line can be minimized.
[0025]
In the electro-optical device according to the aspect of the invention, the conductive line portion interposed between the image signal line and the clock signal line, and the image signal line and the clock signal line are formed on the same plane parallel to the first substrate. The same low resistance metal layer may be used.
[0026]
According to this electro-optical device, the conductive line portion interposed between the image signal line and the clock signal line is formed on the same plane parallel to the substrate as the image signal line and the clock signal line. The effect is exhibited more efficiently. Here, on the same plane, these may be directly wired on a substrate, or an interlayer formed on a base insulating layer formed on the substrate or a semiconductor layer of a switching element such as a TFT. This means that these may be wired on the insulating layer. Further, in the manufacturing process of the electro-optical device, the conductive lines, the image signal lines, and the clock signal lines can be formed from the same low-resistance metal layer such as an Al layer, for example, so that the conductive lines are formed. An increase in the manufacturing process can be minimized.
[0027]
The electro-optical device according to the aspect of the invention may further include a capacitor line that applies a predetermined amount of capacitance to the pixel electrode, and the capacitor line may be connected to the conductive line.
[0028]
According to this electro-optical device, since a predetermined amount of capacitance is applied to the pixel electrode by the capacitance line, high-definition display is possible even when the duty ratio is small. The capacitor line is connected to the conductive line. Therefore, adverse effects on the switching element and the pixel electrode due to the potential fluctuation of the capacitor line are prevented. Moreover, the wiring for setting the capacitance line to a constant potential can be used also as the conductive line, and the external input terminal necessary for setting the capacitance line to the constant potential is, for example, dedicated to the third external input terminal or the conductive line described above. Can also be used as an external input terminal.
[0029]
The electro-optical device according to the aspect of the invention includes a light-shielding frame formed on at least one of the substrate and the counter substrate along a contour of the image display region, the counter substrate being provided to face the substrate. And a capacitance line for applying capacitance to the pixel electrode, the conductive line extending to a position facing the frame, and the capacitance line being connected to the conductive line at the facing position. Good to be.
[0030]
According to this electro-optical device, since the conductive lines are arranged to face the frame of the substrate, space saving on the TFT array substrate can be achieved. For example, the scanning line driving circuit and the data line driving circuit are connected to the first substrate. The peripheral area of the electro-optical device can be formed with a margin, and the effective display area in the electro-optical device is hardly reduced or not at all due to the formation of the conductive line. In addition, since the capacitor line is connected to the conductive line, adverse effects on the switching element and the pixel electrode due to potential fluctuation of the capacitor line are prevented. Moreover, the wiring for setting the capacitance line to a constant potential can be used also as the conductive line, and the external input terminal necessary for setting the capacitance line to the constant potential is, for example, dedicated to the third external input terminal or the conductive line described above. Can also be used as an external input terminal. Further, since the connection between the conductive line and the capacitor line is arranged to face the frame, the space can be effectively used without reducing the effective display area on the TFT substrate.
[0031]
According to another aspect of the invention, an electronic apparatus includes the above-described electro-optical device.
[0032]
According to this electronic apparatus, the electronic apparatus includes the above-described electro-optical device of the present invention, the high-frequency clock noise is reduced, and high-quality image display is possible.
[0033]
Such an operation and other advantages of the present invention will become apparent from the embodiments described below.
[0034]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, a liquid crystal device will be described as an example of an electro-optical device.
[0035]
(Configuration of liquid crystal device)
The configuration of the embodiment of the liquid crystal device will be described with reference to FIGS. FIG. 1 is a plan view showing a configuration of various wirings, peripheral circuits and the like provided on the TFT array substrate in the embodiment of the liquid crystal device, and FIG. 2 shows a more detailed two-dimensional layout of FIG. 3 is a plan view, FIG. 3 is a cross-sectional view taken along line AA ′ of FIG. 2 showing wiring such as an image signal line and a clock signal line, and FIG. 4 is an enlarged plan view of the pixel portion of FIG. 5 is a plan view of the TFT array substrate as viewed from the side of the counter substrate together with the components formed thereon, and FIG. 6 is a cross-sectional view taken along line HH ′ of FIG. 5 including the counter substrate. .
[0036]
In FIG. 1, a liquid crystal device 200 includes a TFT array substrate 1 made of, for example, a quartz substrate or hard glass. 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 and extending in the Y direction, and a plurality of data electrodes 35 arranged in the Y direction are arranged. The scanning lines 31 extending along the X direction, the data lines 35 and the pixel electrodes 11 are respectively interposed between the scanning lines 31 and the conductive and non-conductive states are supplied via the scanning lines 31. A plurality of TFTs 30 are formed as an example of switching elements that are controlled in accordance with scanning signals. On the TFT array substrate 1, a capacitor line 31 ′ (storage capacitor electrode) that is a wiring for a storage capacitor (see FIG. 6) described later is formed in parallel with the scanning line 31.
[0037]
On the TFT array substrate 1, a sampling circuit 301, a data line driving circuit 101, and a scanning line driving circuit 104, which constitute an example of a data signal supply unit, are further formed. Further, scanning provided on both sides of the image display area is provided on the upper side of the image display area defined by the plurality of pixel electrodes 11 (that is, the area of the liquid crystal device in which an image is actually displayed by the change in the alignment state of the liquid crystal). A plurality of wirings 105 for connecting the line drive circuits 104 are provided, and vertical conduction terminals 106 for electrical conduction between the TFT array substrate 1 and the counter substrate are provided at the four corners of the image display area. Is provided. In the following description of FIGS. 1 to 3, the names of signals input via the external input terminals 102 provided along the lower side of the TFT array substrate 1 and the signal wiring thereof are shown for ease of explanation. The same alphabet symbol is added after the signal and the wiring for reference (for example, the signal wiring is called “wiring CLX” for the signal name “clock signal CLX”).
[0038]
The scanning line driving circuit 104 uses a negative power supply VSSY and a positive power supply VDDY for the scanning line driving circuit, which are supplied from the external control circuit via the external input terminal 102 and the wirings VSSY and VDDY as power supplies. The built-in shift register circuit is started by the input of the start signal DY. Then, the scanning signal is pulsed to the scanning line 31 at a predetermined timing based on the reference clock signal CLY for the scanning line driving circuit and the inverted clock signal CLY ′ supplied through the external input terminal 102 and the wirings CLY and CLY ′. The lines are sequentially applied.
[0039]
The data line driving circuit 101 uses the negative power source VSSX and the positive power source VDDX for the data line driving circuit supplied from the external control circuit via the external input terminal 102 and the signal wirings VSSX and VDDX as power sources. The built-in shift register circuit is started by the input of the circuit start signal DX. The timing at which the scanning line driving circuit 104 applies the scanning signal based on the reference clock signal CLX for the data line driving circuit and its inverted clock signal CLX ′ supplied via the external input terminal 102 and the wirings CLX and CLX ′. For example, for each of the image signals VID1 to VID6 that have been serial-parallel converted into six phases supplied via the external input terminal 102 and the wirings VID1 to VID6, the sampling circuit drive signal is output for each data line 35. Are supplied at a predetermined timing via the sampling circuit drive signal line 306.
[0040]
The sampling circuit 301 includes a TFT 302 for each data line 35, wirings VID 1 to VID 6 are connected to the source electrode of the TFT 302, and a sampling circuit drive signal line 306 is connected to the gate electrode of the TFT 302. When the image signals VID1 to VID6 are input, these image signals are sampled. When a sampling circuit driving signal is input from the data line driving circuit 101 via the sampling circuit driving signal line 306, the image signals sampled for the image signals VID1 to VID6 are transmitted from the six adjacent data lines 35. Sequentially applied to each group. As described above, the data line driving circuit 101 and the sampling circuit 301 are configured to supply the image signals VID <b> 1 to VID <b> 6 that are serial-parallel converted into six phases to the data line 35 as data signals. In the present embodiment, the sampling circuit 301 connected to the six adjacent data lines 35 is selected at the same time, and the transfer is sequentially performed for each group of the six data lines 35. It may be selected for each book, or adjacent 2, 3, ..., 5 or 7 or more may be selected simultaneously. Further, the number of serial-parallel conversions of the image signal supplied to the data line 35 is not limited to six phases, but may be five phases or less if the write characteristics of the TFT 302 constituting the sampling circuit 301 are good, and the frequency of the image signal is If it is high, it may be increased to 7 phases or more. At this time, it goes without saying that the external input terminals 102 and image signal lines for image signals are required at least as many as the number of serial-parallel conversions of image signals.
[0041]
As shown in FIG. 2, when the start signal DX is input, the data line driving circuit 101 starts the sequential generation of the transfer signal based on the reference clock signal CLX and its inverted clock signal CLK ′; A waveform control circuit 101b and a buffer circuit 101c are provided which, after waveform shaping and buffering the transfer signal from the shift register circuit 101a, supply the sampling signal to the sampling circuit 301 via the sampling circuit drive signal line 306. The sampling circuit 301 has six TFTs 302 connected in parallel to each sampling circuit drive signal line 306 corresponding to the image signals VID1 to VID6 that are serial-parallel converted into six phases. That is, the switches S1 to S6 constituted by the TFT 302 are connected to the first sampling circuit drive signal line 306 from the left, and the switches S7 to S12 are connected to the second sampling circuit drive signal line 306 from the left. , Switches Sn-5 to Sn are connected to the sampling circuit drive signal line 306 at the right end.
[0042]
Particularly in the present embodiment, as shown in FIGS. 1 and 2, the TFT array substrate 1 includes a constant potential conductive line (hereinafter referred to as a shield line) 80 that also serves as the wiring VSSX for the negative power supply VSSX and a positive line. A shield wire 82 having a constant potential also serving as the wiring VDDX for the power supply VDDX is wired. By these shield lines 80 and 82, the wirings VID1 to VID6 are electrically shielded from the wirings CLX and CLX ′. Therefore, even when the frequency of the clock signal CLX is high, high-frequency clock noise jumping from the wirings CLX and CLX ′ to the wirings VID1 to VID6 can be reduced.
[0043]
Note that the frequency of the scanning line driving clock signal CLY (and its inverted clock signal CLY ′) is much lower than the frequency of the data line driving clock signal CLX (and its inverted clock signal CLX ′). . Therefore, high-frequency clock noise is rarely a problem for the clock signals CLY and CLY ′. However, in the present embodiment, as shown in FIGS. 1 and 2, the wirings VID1 to VID6 are also shielded by the shield lines 80 and 82 from the wirings CLY and CLY ′. . That is, the shield line 80 that extends from the external input terminal 102 and also serves as the negative power source VSSX of the data line driving circuit 101 surrounds the image display area along the light-shielding frame 53 provided on the counter substrate 2. Are wired as follows. Therefore, not only the image signal wirings VID1 to VID6 but also noise jump from the peripheral circuit to the data line 35 to which the data signal is written via the TFT 302 of the sampling circuit 301 can be reduced.
[0044]
In particular, in this embodiment, the wiring VSSX and VDDX are extended to form shield lines 80 and 82, respectively, so that external input terminals and wirings can be shared, thereby simplifying the device configuration and saving space. I can plan. Further, the potentials of the shield lines 80 and 82 are easily set to a constant potential by sharing the constant potential line. However, the power supply wiring and the shield line may be separately wired.
[0045]
Further, if the power supply voltages for driving the data line driving circuit 101 and the scanning line driving circuit 104 are the same, VDDX and VDDY which are positive power supply potentials (positive potential), and negative power supply potential (negative potential). A certain VSSX and VSSY may be shared. Adopting such a configuration is advantageous because the number of external input terminals and wiring extending therefrom can be reduced.
[0046]
In the present embodiment, as shown in FIG. 2, two external input terminals 102 to which a negative power supply VSSX is input are provided, and two wirings VSSX are provided correspondingly. The wirings VID <b> 1 to VID <b> 6 are surrounded on the TFT array substrate 1 by a shield line 80 that is set to the potential (negative potential) of the negative power supply VSSX. In particular, a shield line 80 formed of the same metal layer as Al as the data line 35 is extended between the shift register circuit 101a and the waveform control circuit 101b. The tip of the extended shield line 80 is formed of a conductive layer such as polysilicon, which is the same as the scanning line 31, for example, below the metal layer such as Al via a first interlayer insulating layer as will be described later. The shield line connection portion 81 is connected to the shield line 80 so as to surround the waveform control circuit 101b and the buffer circuit 101c.
[0047]
On the other hand, as shown in FIG. 2, the wirings CLX and CLX ′ are arranged on the TFT array substrate 1 in the portion adjacent to the data line driving circuit 101 by the shield line 82 set to the potential (positive potential) of the positive power supply VDDX. Surrounded by In particular, a shield line 82 formed of the same metal layer such as Al as the data line 35 extends between the waveform control circuit 101b and the buffer circuit 101c, and the tip of the shield line 82 is connected to the scanning line 31, for example. It is connected to the shield line 82 so as to surround the waveform control circuit 101b and the shift register circuit 101a via a shield line connection portion 83 formed of the same conductive layer such as polysilicon.
[0048]
Accordingly, the wirings VID1 to VID6 are configured to be double shielded from the wirings CLX and CLX ′ on the TFT array substrate 1, and the shields for the shift register circuit 101a, the waveform control circuit 101b, and the buffer circuit 101c are also reliable. It is considered to be high. However, even if such a surrounding configuration is not adopted, if the shield line 80 or 82 is interposed between the wirings CLX and CLX ′ and the wirings VID1 to VID6, the shielding effect is somewhat reduced. You can get both.
[0049]
In this embodiment, as shown in FIGS. 1 and 2, the wirings VID1 to VID6 and the wirings CLX and CLX ′ are opposite to each other along the X direction on the TFT array substrate 1 (that is, the former is a watch). Around, the latter being routed counterclockwise). Therefore, since the distance between these wirings increases as a whole, and the electromagnetic wave transmitted between these wirings decreases in accordance with the intervention of the data line driving circuit 101 between these wirings, the clock signals CLX and CLX Even when the frequency of 'is high, the jump of high-frequency clock noise from the wirings CLX and CLX' to the wirings VID1 to VID6 can be further reduced. In addition, the wirings CLX and CLX ′ and the wirings VID1 to VID6 can be routed without any problem even if their directions are switched. That is, the wirings CLX and CLX ′ may be shielded with the negative power supply VSSX, and the wirings VID1 to VID6 may be shielded with the positive power supply VDDX. However, even if the configuration in which the wires are routed in the opposite directions as described above is not employed, if the shield lines 80 or 82 are interposed between the wirings CLX and CLX ′ and the wirings VID1 to VID6, the effect of the shield can be achieved. Can be obtained somewhat.
[0050]
In the present embodiment, the external input terminals 102 for the clock signals CLX and CLX ′ and the external input terminals 102 for the image signals VID1 to VID6 are 3 for the negative power supply VSSX, for the positive power supply VDDX, and for the start signal DX. The two external input terminals 102 are arranged with a predetermined interval therebetween. Preferably, in the region where the external input terminal 102 can be formed in the peripheral portion of the TFT array substrate 1, the external input terminal 102 for the clock signals CLX and CLX ′ and the external input terminal for the image signals VID1 to VID6 as much as possible. 102 are arranged apart from each other, and at least one or more external input terminals 102 are arranged therebetween. With this configuration, it is possible to reduce high-frequency clock noise jumping from the clock wiring to the image signal wiring as compared to, for example, the case where the image signal line and the clock signal line are arranged adjacent to each other.
[0051]
In this embodiment, as shown in FIGS. 1 and 2, the image display region and the plurality of data lines 35 are surrounded on the TFT array substrate 1 by the shield lines 80. For this reason, the image display area and the plurality of data lines 35 are also shielded from the wirings CLX and CLX ′. Therefore, it is possible to reduce the occurrence of high-frequency clock noise in the sampling circuit driving signal output from the data line driving circuit 101, the data signal reaching the TFT 30 or the pixel electrode 11, and the like. However, even if the configuration surrounding the image display area is not employed, if the wirings VID1 to VID6 leading to the sampling circuit 301 are shielded by the shield lines 80 or 82, the shielding effect is somewhat reduced. You can get both.
[0052]
As shown in the cross-sectional view of FIG. 3, the various wirings DY, VSSY,..., VDDX connected to the external input terminal 102 including the shield lines 80 and 82 are the same as the data line 35 such as Al (aluminum). Made of a low resistance metal material. Therefore, even if the routing area of the shield lines 80 and 82 is long, the resistance of the shield lines 80 and 82 is practically sufficiently low. That is, as shown in FIG. 2, the shield line 82 can be extended in a zigzag pattern by sewing the gaps between the various other wirings, the shift register circuit 101a, the waveform control circuit 101b, and the buffer circuit 101c, and also includes the image display area. In addition, the shield wire 80 can be extended over a wide area. Thus, the effect of the shield can be enhanced as a whole with a relatively simple configuration. Further, as shown in FIG. 3, various wirings DY, VSSY,..., VDDX connected to the external input terminal 102 including the shield lines 80 and 82 are formed on the first interlayer insulating layer 42 formed on the TFT array substrate 1. That is, they are formed on the same layer. Therefore, the shielding effect is more efficiently exhibited. Further, with this configuration, in the manufacturing process of the liquid crystal device 200, various wirings DY, VSSY,..., VDDX can be formed in one step from the same low-resistance metal layer such as an Al layer in the same process. This is advantageous in manufacturing.
[0053]
The signal LCCOM input from the external input terminal 102 shown in FIG. 1 to FIG. 3 is a power supply signal for the common electrode, and will be described below via the wiring LCCOM and the conductive material on the above-described vertical conductive terminal 106. It is supplied to a common electrode (see FIG. 7) provided on the substrate.
[0054]
Here, as shown in the plan view of FIG. 4, the capacitor line 31 ′ is formed on the TFT array substrate 1 in parallel with the scanning line 31, for example, from the same conductive polysilicon layer as the scanning line 31. The shield line 80 is connected via a contact hole 80a. With this configuration, wiring for setting the capacitor line 31 ′ at a constant potential can also be used as the shield line 80, and an external input terminal necessary for setting the capacitor line 31 ′ at a constant potential can also be used for the shield line 80. The external input terminal 102 can also be used.
[0055]
Particularly in the present embodiment, the sampling circuit 301 has a TFT at a position facing the light-shielding frame 53 formed on the counter substrate 2 as shown by the hatched area in FIG. 1 and as shown in FIGS. The data line driving circuit 101 and the scanning line driving circuit 104 are provided on the array substrate 1, and are provided on the narrow and long peripheral portion of the TFT array substrate 1 that does not face the liquid crystal layer 50. On the TFT array substrate 1, a sealing material 52 made of a photo-curing resin as an example of a sealing member that surrounds the liquid crystal layer 50 by bonding both substrates around the image display area is provided along the image display area. Is provided. A light-shielding frame 53 is provided between the image display area on the counter substrate 2 and the sealing material 52.
[0056]
When the TFT array substrate 1 is put in a light-shielding case that has an opening corresponding to the image display area, the frame 53 is hidden by the edge of the opening of the case due to a manufacturing error or the like. For example, in order to allow a deviation of about several hundred μm with respect to the case of the TFT array substrate 1, for example, it is formed of a band-shaped light shielding material having a width of, for example, 500 μm or more around the image display region. Is. Such a light-shielding frame 53 is formed on the counter substrate 2 by sputtering, photolithography, and etching using a metal material such as Cr (chrome), Ni (nickel), and Al (aluminum), for example. Or it forms from materials, such as resin black which disperse | distributed carbon and Ti (titanium) in the photoresist.
[0057]
A data line driving circuit 101 and an external input terminal 102 are provided along the lower side of the image display area in the area outside the sealing material 52, and the scanning line driving circuit 104 is provided along two left and right sides of the image display area. Are provided on both sides of the image display area. The counter substrate 2 having substantially the same outline as the sealing material 52 is fixed to the TFT array substrate 1 by the sealing material 52.
[0058]
As described above, the shield line 80 and the sampling circuit 301 are disposed opposite to the frame 53 on the TFT array substrate 1, that is, in the case of this embodiment, provided below the frame 53. For example, the scanning line driving circuit 104 and the data line driving circuit 101 can be formed with a margin in the peripheral portion of the TFT array substrate 1, and effective display in the liquid crystal device 200 can be achieved by forming the shield line 80. There is little or no reduction in area. Further, the shield line 80 extends to a position facing the frame 53, and if the shield line 80 and the capacitor line 31 'are connected at the facing position, the effective display area on the TFT substrate can be reduced. The space can be used effectively.
[0059]
(Configuration of the entire liquid crystal device)
Next, a specific configuration of the liquid crystal device 200 will be described with reference to FIGS. 7 shows the TFT 30 portion of the liquid crystal device, which is a cross-sectional view taken along the line BB ′ in FIG. 4, and FIG. 8 is a cross-sectional view taken along the shield line 80 of the liquid crystal device below the frame. is there. In FIGS. 7 and 8, the scales of the respective layers and members are different in order to make each layer and each member recognizable on the drawings.
[0060]
7, the liquid crystal device 200 includes a TFT array substrate 1, a semiconductor layer 32, a gate insulating layer 33, a scanning line 31 (gate electrode), a first electrode, A first interlayer insulating layer 42, a data line 35, a second interlayer insulating layer 43, a pixel electrode 11, and an alignment film 12 are provided. The liquid crystal device 200 also includes a counter substrate 2 made of, for example, a glass substrate, and a common electrode 21, an alignment film 22, and a light shielding film 23 stacked thereon. The liquid crystal device 200 further includes a liquid crystal layer 50 as an electro-optical material sandwiched between these two substrates.
[0061]
Here, first, the structure of each layer of these layers excluding the TFT 30 will be described in order.
[0062]
The first and second interlayer insulating layers 42 and 43 have NSG (non-silicate glass), PSG (phosphorus silicate glass), BSG (boron silicate glass), and BPSG (boron phosphorus silicate) layers of about 5000 to 15000 angstroms, respectively. Glass), a silicon nitride film, a silicon oxide film, or the like. Note that an interlayer insulating layer serving as a base of the TFT 30 may be formed on the TFT array substrate 1 from a silicate glass film, a silicon nitride film, a silicon oxide film, or the like.
[0063]
The pixel electrode 11 is made of a transparent conductive thin film such as an ITO (indium tin oxide) film. Such a pixel electrode 11 is formed by depositing an ITO film or the like to a thickness of about 500 to 2000 angstroms by sputtering or the like, and then performing a photolithography process or an etching process. When the liquid crystal device 200 is used for a reflective liquid crystal device, the pixel electrode 11 may be formed from an opaque material having a high reflectance such as Al.
[0064]
The alignment film 12 is made of, for example, an organic thin film such as a polyimide thin film. Such an alignment film 12 is formed, for example, by applying a polyimide coating solution and then rubbing it in a predetermined direction so as to have a predetermined pretilt angle.
[0065]
The common electrode 21 is formed over the entire surface of the counter substrate 2. Such a common electrode 21 is formed, for example, by depositing an ITO film or the like to a thickness of about 500 to 2000 angstroms by sputtering or the like, and then performing a photolithography process or an etching process.
[0066]
The alignment film 22 is made of, for example, an organic thin film such as a polyimide thin film. Such an alignment film 22 is formed, for example, by applying a polyimide coating solution and then rubbing it in a predetermined direction so as to have a predetermined pretilt angle.
[0067]
The light shielding film 23 is provided in a predetermined region facing the TFT 30. Such a light shielding film 23 is formed by sputtering, photolithography and etching using a metal material such as Cr or Ni, or a material such as resin black in which carbon or Ti is dispersed in a photoresist, like the frame 53 described above. Formed from. The light shielding film 23 has functions such as improving contrast and preventing color mixture of colors in addition to shielding the semiconductor layer 32 of the TFT 30.
[0068]
The liquid crystal layer 50 is a space surrounded by a sealing material 52 (see FIGS. 5 and 6) between the TFT array substrate 1 and the counter substrate 2 arranged so that the pixel electrode 11 and the common electrode 21 face each other. The liquid crystal is sealed by vacuum suction or the like. The liquid crystal layer 50 takes a predetermined alignment state by the alignment films 12 and 22 in a state where an electric field from the pixel electrode 11 is not applied. The liquid crystal layer 50 is made of, for example, a liquid crystal in which one kind or several kinds of nematic liquid crystals are mixed. The sealing material 52 is an adhesive made of, for example, a photo-curing resin or a thermosetting resin for bonding the two substrates 1 and 2 around them, and a distance between the two substrates is set to a predetermined value. Spacers are mixed.
[0069]
Next, the configuration of each layer related to the TFT 30 will be described in order.
[0070]
The TFT 30 includes a scanning line 31, a semiconductor layer 32 in which a channel is formed by an electric field from the scanning line 31, a gate insulating layer 33 that insulates the scanning line 31 from the semiconductor layer 32, a source region 34 formed in the semiconductor layer 32, A data line 35 and a drain region 36 formed in the semiconductor layer 32 are provided. A corresponding one of the plurality of pixel electrodes 11 is connected to the drain region 36. As will be described later, the source region 34 and the drain region 36 are formed by doping the semiconductor layer 32 with a predetermined concentration of n-type or p-type dopant depending on whether an n-type or p-type channel is formed. Is formed. An n-type channel TFT has an advantage of high operating speed, and is often used as a TFT 30 which is a pixel switching element.
[0071]
The semiconductor layer 32 constituting the TFT 30 is formed, for example, by forming an a-Si (amorphous silicon) film on the TFT array substrate 1 and then subjecting it to an annealing process to solid-phase growth to a thickness of about 500 to 2000 angstroms. To do. At this time, the n-channel TFT 30 may be doped by ion implantation using a dopant of a group V element such as Sb (antimony), As (arsenic), or P (phosphorus). In the case of the p-channel TFT 30, doping is performed by ion implantation using a group III element dopant such as B (boron), Ga (gallium), and In (indium). In particular, in the case where the TFT 30 is an n-channel TFT having an LDD (Lightly Doped Drain) structure, the source region 34 and the drain region 36 are partially adjacent to the channel side of the p-type semiconductor layer 32, and P or the like is provided on a part thereof. A lightly doped region is formed with a dopant of a group V element, and a heavily doped region is formed with a dopant of a group V element such as P. In the case of a p-channel TFT 30, a source region 34 and a drain region 36 are formed in an n-type semiconductor layer 32 using a group III element dopant such as B. When the LDD structure is used as described above, there is an advantage that the short channel effect can be reduced. The TFT 30 may be an offset structure TFT in which ions are implanted into a lightly doped region in the LDD structure, or a high concentration source and drain in a self-aligned manner by doping high concentration impurity ions using a gate electrode as a mask. A self-aligned TFT for forming a region may be used. Needless to say, two gate electrodes may be provided in series to form a dual gate structure, or three or more gate electrodes may be provided in series. By adopting such a configuration, leakage current when the TFT 30 is turned off is reduced, and occurrence of crosstalk or the like can be suppressed. Therefore, a high-quality liquid crystal device can be provided.
[0072]
The gate insulating layer 33 can be 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 angstroms. Thereby, a high-quality insulating film having an excellent interface state between the semiconductor layer 32 and the gate insulating layer 33 can be formed.
[0073]
The scanning line 31 is formed by a photolithography process, an etching process or the like after depositing a polysilicon film by a low pressure CVD method or the like. Alternatively, it may be formed from a metal film such as Al or a metal silicide film. In this case, if the scanning line 31 is arranged as a light shielding film corresponding to a part or the whole of the region covered by the light shielding film 23, a part or all of the light shielding film 23 is caused by the light shielding property of the metal film or the metal silicide film. It can be omitted. In this case, in particular, there is an advantage that it is possible to prevent the pixel aperture ratio from being lowered due to the bonding deviation between the counter substrate 2 and the TFT array substrate 1.
[0074]
The data line 35 may be formed of a transparent conductive thin film such as an ITO film in the same manner as the pixel electrode 11. Alternatively, 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 angstroms by sputtering or the like.
[0075]
In the first interlayer insulating layer 42, a contact hole 37 that leads to the source region 34 and a contact hole 38 that leads to the drain region 36 are formed. The data line 35 is electrically connected to the source region 34 through the contact hole 37 to the source region 34. Further, a contact hole 38 to the drain region 36 is formed in the second interlayer insulating layer 43. The pixel electrode 11 is electrically connected to the drain region 36 through the contact hole 38 to the drain region 36. The pixel electrode 11 described above is provided on the upper surface of the second interlayer insulating layer 43 thus configured. If each contact hole is formed by, for example, dry etching such as reactive etching or reactive ion beam etching, the opening size can be reduced, and a high aperture ratio of the pixel can be realized.
[0076]
In general, in the semiconductor layer 32 in which a channel is formed, photocurrent is generated due to the photoelectric conversion effect of p-Si when light is incident, and the transistor characteristics of the TFT 30 are deteriorated. Since the light shielding film 23 is formed on the substrate 2 at positions facing the respective TFTs 30, incident light is prevented from entering the semiconductor layer 32. Further, in addition to or instead of this, if the data line 35 is formed of an opaque metal thin film such as Al so as to cover the gate electrode from above, incident light to the semiconductor layer 32 (that is, alone or together with the light shielding film 23) In FIG. 7, the incidence of light from the upper side can be effectively prevented.
[0077]
In FIG. 7, the pixel electrodes 11 are each provided with a storage capacitor 70. More specifically, the storage capacitor 70 includes a first storage capacitor electrode 32 ′ formed by the same process as the semiconductor layer 32, a dielectric layer 33 ′ formed by the same process as the gate insulating layer 33, and the scanning line 31. The capacitor line 31 ′ (second storage capacitor electrode), the first and second interlayer insulating layers 42 and 43, and the first and second interlayer insulating layers 42 and 43 formed through the same process as It is comprised from a part of pixel electrode 11 which opposes. Since the storage capacitor 70 is provided in this way, high-definition display is possible even when the duty ratio is small.
[0078]
As shown in the sectional view of FIG. 8, the shield line 80 passes over the first interlayer insulating layer 42 at a position facing the frame 53 and above the plurality of scanning lines 31. The shield line 80 is a low-resistance wiring made of a metal thin film such as Al formed in the same process as the data line 35 described above. Thus, in the manufacturing process of the liquid crystal device 200, the shield line 80 and the data line 35 can be formed in a lump, which is advantageous in manufacturing.
[0079]
Particularly in this embodiment, peripheral circuits such as the sampling circuit 301, the data line driving circuit 101, and the scanning line driving circuit 104 can be formed in the same thin film forming process when forming the TFT 30, which is advantageous in manufacturing. For example, these peripheral circuits are formed in a peripheral portion on the TFT array substrate 1 from a plurality of TFTs having a complementary structure composed of an n-channel polysilicon TFT and a p-channel polysilicon TFT.
[0080]
Although not shown in FIGS. 7 and 8, in the liquid crystal device 200, for example, TN on the side on which the projection light of the counter substrate 2 is incident and on the side on which the projection light of the TFT array substrate 1 is emitted, respectively. (Twisted nematic) mode, STN (super TN) mode, D-STN (double-STN) mode, etc., depending on the normal white mode / normally black mode, polarizing film, retardation film, polarizing A plate or the like is arranged in a predetermined direction.
[0081]
Further, since the liquid crystal device 200 described above is applied to a color liquid crystal projector, the three liquid crystal devices 200 are used as RGB light valves, and each device is connected to a dichroic mirror for RGB color separation. The decomposed light of each color is incident as incident light. Therefore, in each embodiment, the counter substrate 2 is not provided with a color filter. However, in the liquid crystal device 200 as well, an RGB color filter may be formed on the counter substrate 2 together with the protective film in a predetermined region facing the pixel electrode 11 where the light shielding film 23 is not formed. Alternatively, a color filter layer may be built in with an RGB color resist so as to correspond to each pixel on the TFT array substrate 1. In this way, the liquid crystal device of this embodiment can be applied to a color liquid crystal device such as a direct-view type or a reflective type color liquid crystal television other than the liquid crystal projector. Furthermore, a micro lens may be formed on the counter substrate 2 so as to correspond to one pixel. In this way, a bright liquid crystal device can be realized by improving the collection efficiency of incident light. Furthermore, a dichroic filter that produces RGB colors by using interference of light may be formed by depositing several layers of interference layers having different refractive indexes on the counter substrate 2. According to this counter substrate with a dichroic filter, a brighter color liquid crystal device can be realized.
[0082]
In the liquid crystal device 200, a planarizing film may be further applied on the second interlayer insulating layer 43 by spin coating or the like in order to suppress alignment failure of liquid crystal molecules on the TFT array substrate 1 side, or CMP (Chemical Mechanical Polishing) processing may be performed. Alternatively, the second interlayer insulating layer 43 may be formed of a planarizing film.
[0083]
Although the switching element of the liquid crystal device 200 has been described as being a normal stagger type or coplanar type polysilicon TFT, the present embodiment is also applied to other types of TFTs such as an inverted stagger type TFT and an amorphous silicon TFT. Is valid.
[0084]
In the liquid crystal device 200, as an example, the liquid crystal layer 50 is composed of nematic liquid crystal. However, if polymer dispersed liquid crystal in which liquid crystal is dispersed as fine particles in a polymer is used, the alignment films 12 and 22 and the above-described polarized light are used. Films, polarizing plates, and the like are not necessary, and the advantages of high brightness and low power consumption of the liquid crystal device due to the increased light utilization efficiency can be obtained. Furthermore, when the liquid crystal device 200 is applied to a reflective liquid crystal device by forming the pixel electrode 11 from a metal film having a high reflectance such as Al, SH in which liquid crystal molecules are substantially vertically aligned in a state where no voltage is applied. (Super homeotropic) type liquid crystal may be used. 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 an electric field (vertical electric field) perpendicular to the liquid crystal layer 50, but an electric field (horizontal) parallel to the liquid crystal layer 50 is provided. The pixel electrode 11 is composed of a pair of electrodes for generating a horizontal electric field so that an electric field is applied (that is, the side of the TFT array substrate 1 is not provided with the electrode for generating a vertical electric field on the side of the counter substrate 2). It is also possible to provide a lateral electric field generating electrode. Using a horizontal electric field in this way is more advantageous in widening the viewing angle than using a vertical electric field. In addition, the present embodiment can be applied to various liquid crystal materials (liquid crystal phases), operation modes, liquid crystal alignments, driving methods, and the like. In the above-described embodiment, the configuration in which the TFT is formed on the substrate has been described. However, the present invention is not limited to such a configuration, and the configuration in which the switching element is formed on the silicon substrate is also applicable. Further, although the liquid crystal is used as the electro-optical material, the present invention is not limited to the liquid crystal but can be applied to electroluminescence, a plasma display, or the like.
[0085]
In the embodiment described above, well-known peripheral circuits such as a precharge circuit and an inspection circuit may be provided under the frame 53 and in the peripheral portion of the TFT array substrate 1. The precharge circuit uses the data signal supplied from the data line driving circuit 101 to the data line 35 for the purpose of improving the contrast ratio, stabilizing the potential level of the data line 35, and reducing line unevenness on the display screen. This circuit reduces the load when writing a data signal to the data line 35 by supplying a precharge signal at the preceding timing. For example, Japanese Patent Laid-Open No. 7-295520 discloses an example of such a precharge circuit. On the other hand, the inspection circuit is a circuit for inspecting the quality, defects, and the like of the liquid crystal device in the middle of manufacture or at the time of shipment under the frame 53 or in the periphery of the TFT array substrate.
[0086]
In the above embodiment, as disclosed in JP-A-9-127497, JP-B-3-52611, JP-A-3-125123, JP-A-8-171101, etc. A light shielding layer made of, for example, a refractory metal may be provided at a position facing the TFT 30 on the array substrate 1 (that is, below the TFT 30). If a light shielding layer is also provided below the TFT 30 as described above, it is possible to prevent the return light from the TFT array substrate 1 from entering the TFT 30 in advance. Therefore, the liquid crystal device 200 can be suitably used as a light valve for a projector.
[0087]
Furthermore, in the above embodiment, the switching element may be constituted by a two-terminal nonlinear element such as a TFD (Thin Film Diode) instead of the TFT 30. In this case, one of the data line and the scanning line is arranged on the counter substrate to function as a common electrode, and a switching element is arranged between the other line provided on the TFT array substrate and the pixel electrode. LCD drive. Even in such a configuration, the pixel signal line and the data line are shielded from the clock signal line, so that the effect of preventing the high-frequency clock noise from jumping into the image signal and the data signal is exhibited.
[0088]
(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.
[0089]
First, the scanning line driving circuit 104 applies scanning signals to the scanning lines 31 in a pulse-sequential manner at predetermined timing.
[0090]
In parallel with this, when receiving parallel image signals from the six wirings VID1 to VID6, the sampling circuit 301 samples these image signals. The data line driving circuit 101 supplies a sampling circuit driving signal for each data line for each of the six wirings VID1 to VID6 in accordance with the timing at which the scanning line driving circuit 104 applies the gate voltage. The TFT 302 is turned on. As a result, the sampled data signals are sequentially applied to the six adjacent data lines 35 to the sampling circuit 301. That is, the parallel image signals VID 1 to VID 6 subjected to serial-parallel conversion into six phases input from the wirings VID 1 to VID 6 by the data line driving circuit 101 and the sampling circuit 301 are supplied to the data line 35.
[0091]
As described above, in the TFT 30 to which both the scanning signal (gate voltage) and the data signal (source voltage) are applied, the pixel electrode 11 is connected to the pixel region 11 via the source region 34 and the channel and drain region 36 formed in the semiconductor layer 32. A voltage is applied. The voltage of the pixel electrode 11 is held by the storage capacitor (see FIG. 7) for a time that is, for example, three orders of magnitude longer than the time when the source voltage is applied. In particular, since the lines VID1 to VID6 are shielded from the lines CLX and CLX ′ by the shield lines 80 and 82, the lines CLX and CLX ′ to the lines VID1 to VID6 even when the frequency of the clock signal CLX is high. The high frequency clock noise can be reduced.
[0092]
As described above, when a voltage is applied to the pixel electrode 11, the alignment state of the liquid crystal in the portion of the liquid crystal layer 50 sandwiched between the pixel electrode 11 and the common electrode 21 changes. In accordance with the applied voltage, incident light cannot pass through the liquid crystal part. In the normally black mode, incident light can pass through the liquid crystal part according to the applied voltage. The liquid crystal device 200 emits light having a contrast corresponding to the image signal.
[0093]
As a result, even when high-resolution serial image signals VID1 to VID6 are input, the high-frequency clock signals CLX and CLX ′ are used in response to the high-frequency serial image signals VID1 to VID6. The image quality is hardly or not deteriorated due to the occurrence of clock noise, and high-quality image display is possible.
[0094]
(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.
[0095]
First, FIG. 9 shows a schematic configuration of an electronic apparatus including the liquid crystal device 200 as described above.
[0096]
In FIG. 9, the electronic apparatus includes a display information output source 1000, a display information processing circuit 1002, a drive circuit 1004, a liquid crystal device 200, 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 that tunes and outputs a television signal, and the like. Based on this, display information such as an image signal in a predetermined format is output to the display information processing circuit 1002. The display information processing circuit 1002 includes various known processing circuits such as an amplification / polarity inversion circuit, a serial-parallel conversion circuit, a rotation circuit, a gamma correction circuit, and a clamp circuit, and is input based on a clock signal. A digital signal is sequentially generated from the displayed information and is output to the drive circuit 1004 together with the clock signal CLK. The drive circuit 1004 drives the liquid crystal device 200. The power supply circuit 1010 supplies predetermined power to the above-described circuits. Note that the drive circuit 1004 may be mounted on the TFT array substrate constituting the liquid crystal device 200, and in addition to this, the display information processing circuit 1002 may be mounted.
[0097]
Next, specific examples of the electronic apparatus configured as described above are shown in FIGS.
[0098]
In FIG. 10, a liquid crystal projector 1100 as an example of an electronic device prepares three liquid crystal modules including the liquid crystal device 200 in which the drive circuit 1004 described above is mounted on a TFT array substrate, and RGB light valves 200R and 200G, respectively. And 200B as a projector. In the liquid crystal projector 1100, when projection light is emitted from a lamp unit 1102 of a white light source such as a metal halide lamp, light components R, G, and R corresponding to the three primary colors of RGB are obtained by three mirrors 1106 and two dichroic mirrors 1108. Divided into B, the light valves are guided to the light valves 200R, 200G and 200B corresponding to the respective colors. At this time, in particular, the B light is guided through a relay lens system 1121 including an incident lens 1122, a relay lens 1123, and an exit lens 1124 in order to prevent light loss due to a long optical path. The light components corresponding to the three primary colors modulated by the light valves 200R, 200G, and 200B are synthesized again by the dichroic prism 1112 and then projected as a color image on the screen 1120 via the projection lens 1114.
[0099]
In the present embodiment, in particular, if the light shielding layer is also provided below the TFT as described above, the reflected light and incident light from the projection optical system in the liquid crystal projector based on the incident light from the liquid crystal device 200 are prevented. Reflected light from the surface of the TFT array substrate when passing, part of incident light (part of R light and G light) that penetrates the dichroic prism 1112 after being emitted from another liquid crystal device, etc. as return light Even if it is incident from the TFT array substrate side, it is possible to sufficiently shield light from a channel such as the pixel switching TFT 30. In this case, even if a prism suitable for miniaturization is used in the projection optical system, an AR (Anti Reflection) film for preventing return light is attached between the TFT array substrate of each liquid crystal device and the prism, or a polarizing plate. It is not necessary to perform an AR coating treatment on the surface, which is very advantageous in reducing the size and simplification of the configuration.
[0100]
In FIG. 11, a laptop personal computer (PC) 1200 compatible with multimedia, which is another example of an electronic device, includes the above-described liquid crystal device 200 in a top cover case, and further includes a CPU, a memory, a modem, and the like. And a main body 1204 in which a keyboard 1202 is incorporated.
[0101]
In FIG. 12, a pager 1300 as another example of an electronic device includes a light guide including a backlight 1306a in a liquid crystal device 200 in which the driving circuit 1004 is mounted on a TFT array substrate in a metal frame 1302 to form a liquid crystal module. 1306, a circuit board 1308, first and second shield plates 1310 and 1312, two elastic conductors 1314 and 1316, and a film carrier tape 1318. In the case of this example, the above-described display information processing circuit 1002 (see FIG. 9) may be mounted on the circuit board 1308 or may be mounted on the TFT array substrate of the liquid crystal device 200. Further, the above-described drive circuit 1004 can be mounted on the circuit board 1308.
[0102]
Since the example shown in FIG. 12 is a pager, a circuit board 1308 and the like are provided. However, in the case of the liquid crystal device 200 in which the driving circuit 1004 and the display information processing circuit 1002 are mounted to form a liquid crystal module, the liquid crystal device 200 fixed in the metal frame 1302 is used as or in addition to the liquid crystal device. As a backlight type liquid crystal device incorporating the light guide 1306, it is possible to produce, sell, use, and the like.
[0103]
As shown in FIG. 13, in the case of the liquid crystal device 200 that does not include the drive circuit 1004 or the display information processing circuit 1002, a TCP in which an IC 1324 including the drive circuit 1004 and the display information processing circuit 1002 is mounted on a polyimide tape 1322. (Tape Carrier Package) 1320 can be physically and electrically connected to the periphery of the TFT array substrate 1 through an anisotropic conductive film to produce, sell, use, etc. as a liquid crystal device Is possible.
[0104]
In addition to the electronic devices described above with reference to FIGS. 10 to 13, a liquid crystal television, a viewfinder type or a monitor direct-view type video tape recorder, a car navigation device, an electronic notebook, a calculator, a word processor, an engineering workstation ( EWS), a mobile phone, a video phone, a POS terminal, a device provided with a touch panel, and the like are examples of the electronic device shown in FIG.
[0105]
As described above, according to the present embodiment, generation of high-frequency clock noise is reduced, and various electronic devices including the liquid crystal device 200 capable of displaying high-quality images can be realized.
[0106]
【The invention's effect】
According to the electro-optical device of the first aspect, since the image signal line is shielded from the clock signal line by the constant potential conductive line wired on the first substrate, the clock signal line to the image signal line. Therefore, high-frequency image display can be performed in accordance with a high-frequency image signal for displaying a high-resolution image.
[0107]
According to the electro-optical device according to the second aspect, since the wiring of the conductive line and the constant potential line and the external input terminal can be shared, the configuration can be simplified and the space can be saved. With such a configuration, an electro-optical device capable of displaying a high-quality image can be realized.
[0108]
According to the electro-optical device of the third aspect, the image signal line is shielded twice from the clock signal line, so that the generation of high-frequency clock noise in the image signal and the data signal is more powerful and reliable. Can be highly reduced.
[0109]
According to the electro-optical device of the fourth aspect, the image signal line and the clock signal line are routed in opposite directions with respect to the data line driving circuit, thereby further reducing the high-frequency clock noise from entering the image signal line. Therefore, the effect of the shield can be enhanced efficiently by a simple configuration.
[0110]
According to the electro-optical device of the fifth aspect, the first and second external input terminals are arranged at a predetermined interval from each other with the third external input terminal interposed therebetween. Since the jumping in of high frequency clock noise can be reduced, the effect of the shield can be improved efficiently by a simple configuration.
[0111]
According to the electro-optical device according to the sixth aspect, since the image display area and the plurality of data lines can be shielded from the clock signal line, it is possible to reduce the occurrence of high-frequency clock noise in the data signal on the data line. A quality image can be displayed.
[0112]
According to the electro-optical device of the seventh aspect, since the conductive wire is provided under the frame of the substrate, the space on the substrate can be effectively used.
[0113]
10. The electro-optical device according to claim 8, wherein a conductive wire having a high shielding effect can be formed by a relatively simple manufacturing process, and a high-quality image display can be performed at low cost. Can be realized.
[0114]
According to the electro-optical device of the tenth aspect, other than the constant potential line and the external input terminal for setting the capacitance line to a constant potential while preventing the adverse effect on the switching element and the pixel electrode due to the potential fluctuation of the capacitance line. Therefore, a high-quality image can be displayed with a relatively simple configuration.
[0115]
According to the electronic device of the eleventh aspect, it is possible to realize various electronic devices such as a liquid crystal projector, a personal computer, and a pager that can reduce high-frequency clock noise and display a high-quality image.
[Brief description of the drawings]
FIG. 1 is a schematic plan view of various wirings and peripheral circuits formed on a TFT array substrate in an embodiment of a liquid crystal device.
FIG. 2 is a schematic plan view showing the two-dimensional layout of FIG. 1 in more detail.
3 is a cross-sectional view taken along the line AA ′ on the TFT array substrate of FIG. 1;
4 is an enlarged plan view of an end portion of an image display area for pixel electrodes, scanning lines, data, and the like formed on the TFT array substrate of FIG. 1. FIG.
5 is a plan view showing an overall configuration of the liquid crystal device of FIG. 1. FIG.
6 is a cross-sectional view showing an overall configuration of the liquid crystal device of FIG. 1. FIG.
7 is a cross-sectional view of a pixel switching TFT provided in an image display region of the liquid crystal device of FIG.
8 is a cross-sectional view of a shield line portion provided in a frame region of the liquid crystal device of FIG.
FIG. 9 is a block diagram showing a schematic configuration of an embodiment of an electronic device according to the present invention.
FIG. 10 is a cross-sectional view illustrating a liquid crystal projector as an example of an electronic apparatus.
FIG. 11 is a front view showing a personal computer as another example of an electronic apparatus.
FIG. 12 is an exploded perspective view showing a pager as an example of an electronic apparatus.
FIG. 13 is a perspective view showing 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 ... Alignment film
23 ... Light-shielding film
30 ... TFT
31 ... Scanning line (gate electrode)
32 ... Semiconductor layer
33 ... Gate insulating layer
34 ... Source area
35 ... Data line
36 ... Drain region
37, 38 ... contact holes
42. First interlayer insulating layer
43 ... Second interlayer insulating layer
50 ... Liquid crystal layer
52 ... Sealing material
53. Picture frame
70 ... Storage capacity
80, 82 ... shielded wire (constant potential wire)
101: Data line driving circuit
102: External input terminal
104: Scanning line driving circuit
200 ... Liquid crystal device
301: Sampling circuit
302 ... TFT

Claims (13)

A plurality of scanning lines on the substrate, a plurality of data lines intersecting the plurality of scanning lines, a plurality of switching elements provided corresponding to the intersection of the plurality of scanning lines and the data lines, and the plurality of switching An image display area including a plurality of pixel electrodes provided corresponding to the element;
An image signal line for supplying an image signal input from the first external input terminal;
Data signal supply means for supplying an image signal supplied to the image signal line as a data signal to the plurality of data lines based on a clock signal;
A clock signal line for supplying the clock signal input from the second external input terminal to the data signal supply means;
A conductive line disposed so as to surround the image display region and a region where the image signal line is wired, electrically shielding the image signal line from the clock signal line, and supplying a constant potential power; An electro-optical device comprising:   The electro-optical device according to claim 1, wherein the conductive line includes a portion composed of a constant potential line that supplies the constant potential power to the data signal supply unit. The constant potential lines are composed of first and second constant potential lines that supply different constant potential power supplies to the data signal supply means,
The conductive line portion composed of the first constant potential line surrounds the image signal line on the substrate,
The electro-optical device according to claim 2, wherein the conductive line portion including the second constant potential line surrounds the clock signal line on the substrate. The data signal supply means includes a sampling circuit that samples the image signal, and a data line drive circuit that receives the power supply from the constant potential line and drives the sampling circuit based on the clock signal,
4. The electro-optical device according to claim 2, wherein the image signal line and the clock signal line are routed from opposite directions with respect to the data line driving circuit on the substrate. 5.   The first and second external input terminals are arranged at a predetermined distance from each other at the periphery of the substrate, and the constant-potential power source is connected between the first and second external input terminals. The electro-optical device according to any one of claims 2 to 4, wherein a third external input terminal for inputting to the constant potential line is disposed. A counter substrate is provided opposite to the substrate, and further includes a light-shielding frame formed on at least one of the substrate and the counter substrate along the outline of the image display region,
6. The electro-optical device according to claim 1, wherein the conductive line includes a portion provided on the substrate along the frame at a position facing the frame.   The electro-optical device according to claim 1, wherein the conductive line and the data line are formed of the same low-resistance metal material.   The conductive line portion interposed between the image signal line and the clock signal line, and the image signal line and the clock signal line are composed of the same low-resistance metal layer formed on the same plane parallel to the substrate. The electro-optical device according to claim 1, wherein   9. The electro-optical device according to claim 1, further comprising a capacitor line that applies a predetermined amount of capacitance to the pixel electrode, wherein the capacitor line is connected to the conductive line. apparatus.   A light-shielding frame formed on at least one of the substrate and the counter substrate along a contour of the image display area, and a capacitor for providing a capacity to the pixel electrode. 2. The apparatus according to claim 1, further comprising a wire, wherein the conductive line extends to a position facing the frame, and the capacitor line is connected to the conductive line at the facing position. 6. The electro-optical device according to any one of items 1 to 5.   The electro-optical device according to claim 2, wherein the constant potential line surrounds the clock signal line. The data signal supply means includes a shift register circuit, a waveform control circuit that shapes a transfer signal from the shift register circuit, and a buffer circuit for buffering a signal from the waveform control circuit,
The electro-optical device according to claim 2, wherein the constant potential line surrounds the waveform control circuit and the buffer circuit.   An electronic apparatus comprising the electro-optical device according to claim 1.

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