JP2002287667A - Optoelectronic device, its driving method and electronic equipment and projection type display device having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal device in which the largeness of the number of display pixels per a unit area and the height of an opening ratio are made to coexist with each other and the electronic equipment provided with the liquid crystal device. SOLUTION: In this liquid crystal device, pixel electrodes which can be selected by the same scanning line or the same data line are made to be the plural number by making one part of pixel transistors which are controlled by the same scanning line perform selectively an opening/closing operation by a scanning line voltage. As a result, the number of data lines or scanning lines can be reduced and it becomes possible to raise an opening ratio.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technical field of an electro-optical device such as a liquid crystal device of a matrix drive system driven by a thin film transistor (hereinafter, referred to as a TFT) and an electronic apparatus using the same.

[0002]

2. Description of the Related Art Conventionally, in a liquid crystal device of an active matrix drive system using a TFT drive, as shown in FIG.
121,. . . , Scan lines 200, 201,. . . , And a large number of TFTs 3 and pixel electrodes 5 corresponding to these intersections. In addition to these, the shift register circuit 1, the scanning line driving circuit 2, and the sampling transistors 10, 11,. . . , Etc. are provided.

The shift register circuit 1 receives sampling signal lines 100, 101, 102, 103,... According to a horizontal scanning start signal DX and a horizontal scanning clock CLX. . . Sequentially output sampling signals. The sampling transistors 10, 11, 12, 13,. . . Are sampling signal lines 100, 101, 102, 103,. . . Open and close according to the sampling signal of the video signal input DIN
From the data lines 120, 121, 12
2, 123,. . . Sampling.

[0004] The scanning line driving circuit 2 outputs a vertical scanning start signal D
Y, the scanning line 20 according to the horizontal scanning clock signal CLY.
0, 201, 202,. . . Sequentially output selection signals. The pixel transistors 3 are scanning lines 200, 201, 20
2,. . . Data lines 120, 12
1, 122, 123,. . . Is applied to the pixel electrode 5.

FIG. 14 shows an example of a layout near the pixel electrode 5. Data lines 120 and 121 and scanning lines 200 and 20
1, a transistor layer 7 forming the pixel transistor 3,
The pixel electrode 5 has a multilayer structure arranged in different layers, and each layer is connected by a contact 6 as necessary.

The pixel electrode 5 is connected to the data line 122 via the pixel transistor 3 whose opening and closing are controlled by the scanning lines 200 and 201.

Next, the operation of the configuration example shown in FIGS. 13 and 14 will be described using an operation timing example shown in FIG.
The pixel transistor 3, the sampling transistors 10, 11,. . . Has a characteristic that the gate voltage is ON when the gate voltage is Hi level and OFF when the gate voltage is Low level.

First, the scanning line 200 is set to the Hi level to turn on the pixel transistor 3 connected to the scanning line 200, and then the sampling signal 100 is output to the Hi level to turn the sampling transistor 10 on.
Thus, the video signal S10 input from DIN is sampled on the data line 120 and applied to the pixel electrode 5.

Thereafter, the other data lines 121, 122, 12
3, 124,. . . By repeating the same operation for, one horizontal scan is completed, and the scanning lines 201 and
202,. . . By repeating the same operation, the display operation of one screen is completed.

[0010]

In a screen display area defined by a plurality of pixel electrodes arranged in a matrix, although the pixel electrode portion transmits light sufficiently, pixel transistors, data lines, and scanning lines are provided. Does not transmit light sufficiently. Therefore, when the pixel electrode area in the screen display area is small, the amount of transmitted light is small, and the display image is dark. The area of the pixel electrode with respect to the entire screen display area is generally called an aperture ratio. As a basic requirement of a liquid crystal display device, it is said that the aperture ratio should be as high as possible. On the other hand, since high-definition image display is required, it is said that the larger the number of display pixels per unit area, the better. In order to achieve both the high aperture ratio and the large number of display pixels per unit area, it is necessary to reduce the area of other regions as the pixel electrode area decreases. Simple downsizing comes with great difficulty due to the need to maintain basic electrical properties and manufacturing challenges.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a liquid crystal device having both a large number of display pixels per unit area and a high aperture ratio, and the liquid crystal device. An electronic device provided with the electronic device.

[0012]

In order to achieve the above object, the present invention provides a plurality of scanning lines, a plurality of data lines intersecting the plurality of scanning lines, the plurality of scanning lines and the plurality of scanning lines. A first pixel electrode and a second pixel electrode provided corresponding to intersections of the data lines, a first switching element connecting the data line and the first pixel electrode, and a data line and the second pixel electrode A first switching element and the second switching element are controlled by the same scanning line, and when a first selection signal is input to the scanning line, When the first and second switching means are turned on and a second selection signal is input to the scanning line, the first switching means is turned on and the second switching means is turned off. I do.

Thus, a plurality of pixel electrodes can be selected by the same scanning line and the same data line, so that the number of data lines or scanning lines can be reduced.
The aperture ratio can be increased.

A plurality of scanning lines; a plurality of data lines intersecting the plurality of scanning lines; a first pixel electrode provided corresponding to an intersection of the plurality of scanning lines and the plurality of data lines; A first switching element for connecting the data line to the first pixel electrode; a second switching element for connecting the data line to the second pixel electrode; The switching element and the second switching element are controlled by the same scanning line, and when a first selection signal is input to the scanning line, the first and second switching means are turned on and the second switching means is turned off. When the second switching signal is input to the scanning line and the second switching means is conductive, the first switching means is non-conductive.

By adopting such a configuration, first,
The second switching means can be selectively made conductive.

The switching element may be constituted by an N-type or P-type thin film transistor.

Further, in the method of driving an electro-optical device according to the present invention, a plurality of scanning lines, a plurality of data lines intersecting the plurality of scanning lines, and an intersection of the plurality of scanning lines and the plurality of data lines are provided. First and second pixel electrodes provided correspondingly, a first switching element for connecting the data line to the first pixel electrode, and a second switching element for connecting the data line to the second pixel electrode. An electro-optical device driving method for driving an electro-optical device having two switching elements, wherein the first switching element and the second switching element are controlled by the same scanning line, and a first selection signal is scanned by the scanning. The first switching means is turned on by inputting a second selection signal to the scanning line by inputting the first and second switching means to the scanning line. Stage characterized by non-conductive.

By employing such a driving method, a plurality of pixel electrodes can be selected by the same scanning line and the same data line, so that the number of data lines or scanning lines of the panel can be reduced, and the number of apertures can be reduced. It is possible to increase the rate.

A plurality of scanning lines; a plurality of data lines intersecting the plurality of scanning lines; a first pixel electrode provided corresponding to an intersection of the plurality of scanning lines and the plurality of data lines; Driving an electro-optical device having a second pixel electrode, a first switching element connecting the data line to the first pixel electrode, and a second switching element connecting the data line to the second pixel electrode A driving method for the electro-optical device, wherein the first switching element and the second switching element are controlled by the same scanning line, and a first selection signal is input to the scanning line, whereby the first switching is performed. Means, the second switching means is turned off, the second switching means is turned off, and the second selection signal is inputted to the scanning line, whereby the second switching means is turned on and the first switch is turned on. Characterized by a non-conductive grayed means.

By adopting such a configuration, the first,
The second switching means can be selectively made conductive. According to another aspect of the invention, an electronic apparatus includes the electro-optical device and a control device that controls the electro-optical device.

According to a fourth aspect of the present invention, there is provided a projection display apparatus comprising: a light source; an electro-optical device according to claim 4, which modulates and transmits the light from the light source; and collects the light modulated by the electro-optical device. Projection optical means for illuminating and magnifying projection.

According to the present invention, it is possible to provide an electronic device or a projection display device capable of displaying a high-definition image having a relatively high aperture ratio and a large number of display pixels per unit area.

[0023]

Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment] FIG. 1 shows a configuration example of an active matrix type liquid crystal display device of the present invention.

The shift register circuit 1 receives sampling signal lines 100, 101, 102, 103,... According to a horizontal scanning start signal DX and a horizontal scanning clock CLX. . . Sequentially output sampling signals. The sampling transistors 10, 11, 12, 13,. . . Are sampling signal lines 100, 101, 102, 103,. . . Open and close according to the sampling signal of the video signal input DIN
From the data lines 120, 121, 12
2, 123,. . . Sampling.

The scanning line driving circuit 2 outputs a vertical scanning start signal D
Y, according to the vertical scanning clock CLY, the scanning lines 200, 2
01, 202,. . . Sequentially output selection signals. The pixel transistors 3, 4 are connected to the scanning lines 200, 201, 20
2,. . . Data lines 120, 12
1, 122, 123,. . . Is applied to the pixel electrode 5.

FIG. 2 is an example of a layout near the pixel electrode 5. Data lines 120 and 121 and scanning lines 200 and 20
1, a transistor layer 7 forming pixel transistors 3 and 4 and pixel electrodes 5a and 5b have a multilayer structure arranged in different layers, and each layer is connected to a pixel electrode 5a by a contact 6 as necessary. , 5b are arranged side by side in the longitudinal direction of the scanning lines, and
It is connected to the data line 120 via the pixel transistors 3 and 4 whose opening and closing are controlled by 0.

Next, the operation of the configuration example shown in FIGS. 1 and 2 will be described with reference to the operation timing example shown in FIG.

First, V2 is applied to the scanning line 200, and a Hi level is output to the sampling signal 100 to turn on the sampling transistor 10. Here, since the pixel transistors 3 and 4 have gate voltage-drain current characteristics A and B as shown in FIG. 4, respectively, if the voltage of the scanning line 200 is V2, both transistors are turned on, In V1, the pixel transistor 4
Only in the ON state, and both transistors are O
The state becomes the FF state. Therefore, the video signal S10 is applied to both the pixel electrodes 5a and 5b.

Next, the video signal S11 for the pixel electrode 5b is sampled on the data line 120, and V1 is applied to the scanning line 200 to turn off the pixel transistors 3 and 4 respectively.
F, set to ON state. This makes it possible to apply the video signal S11 to the pixel electrode 5b again, and the predetermined video signals S10 and S11 are applied to the pixel electrodes 5a and 5b, respectively. Hereinafter, the other data lines 121, 122, 12
3, 124,. . . By repeating the same operation for, one horizontal scan is completed.

FIG. 5 is a diagram showing another example of operation timing.

First, V2 is applied to the scanning line 200. The sampling signals 100, 101, 102. . . Are sequentially applied, and the transistors 10, 11, 12,. . . Are sequentially turned on and the odd-numbered pixel video signals S10, S1
2, S14. . . Is sampled on each data line, and each video signal is applied to the pixel electrodes 5a and 5b.

Next, the voltage applied to the scanning line 200 is set to V1, and the sampling signals 100, 101, 10
2. . . Are sequentially applied, and transistors 10, 11, 1
2. . . Are sequentially turned on, and the even-numbered pixel video signals S11, S13, S15. . . Is sampled on each data line, and each video signal is applied to the pixel electrode 5b, thereby completing one horizontal scan.

The pixel transistors 3 and 4 have gate voltage-drain current characteristics A and B as shown in FIG.
When the gate voltage is set to V0, only the pixel transistor 4 is turned on, and when the gate voltage is set to V2, only the pixel transistor 3 is turned on.
When the gate voltage is V1, the pixel transistor 3,
4 are both OFF. FIG. 7 shows an example of operation timing when a pixel transistor having such characteristics is used.
8 are the same as the timing operation examples shown in FIGS. 3 and 5, respectively.

[Second Embodiment] FIG. 9 shows another layout example near the pixel electrodes of the active matrix type liquid crystal display device shown in FIG.

The data lines 120, 121 and the scanning line 200,
201, the transistor layer 7 forming the pixel transistors 3 and 4, and the pixel electrodes 5a and 5b have a multilayer structure arranged in different layers, and each layer is connected to the pixel electrode 5a by a contact 6 as necessary. , 5b are arranged with the data line 120 interposed therebetween, and each of the scanning lines 200
Connected to the data lines 120 and 121 via the pixel transistors 3 and 4 whose opening and closing are controlled.

The operation timing example of this layout example is the same as that of the first embodiment.

[Third Embodiment] FIG. 10 shows another layout example near the pixel electrodes of the active matrix type liquid crystal display device shown in FIG.

The data lines 120, 121 and the scanning lines 200,
201, the transistor layer 7 forming the pixel transistors 3 and 4, and the pixel electrodes 5a and 5b have a multilayer structure arranged in different layers, and the respective layers are connected by contacts 6 as necessary.

The pixel electrodes 5a and 5b are arranged with the scanning line 200 interposed therebetween.
21.

When the pixel transistors 3 and 4 have the gate voltage-drain current characteristics A and B as shown in FIG. 4, when the gate voltage is V0, both the pixel transistors 3 and 4 are in the OFF state, When the voltage is V1, only the pixel transistor 4 is ON, and the gate voltage is V2.
In this case, both the pixel transistors 3 and 4 are turned on. FIG. 11 shows an example of operation timing when a pixel transistor having such characteristics is used.

First, the transistor 10 is turned on by the sampling signal 100, the video signal S10 for the pixel electrode 5a is sampled on the data line 120, and V2 is applied to the scanning line 200. Here, since the pixel transistors 3 and 4 are turned on, the pixel electrodes 5a and 5b
Are both supplied with the video signal S10.

Thereafter, the other data lines 121, 122, 12
3, 124,. . . By repeating the same operation for, one horizontal scan is completed.

Next, the transistor 10 is turned on by the sampling signal 100, and the video signal S20 for the pixel electrode 5b is sampled on the data line 120 and V1 is applied to the scanning line 200. Here, since the pixel transistor 3 is turned off and the pixel transistor 4 is turned on, the previously written S10 remains on the pixel electrode 5a, and the video signal S20 is newly applied to the pixel electrode 5b.

Thereafter, the other data lines 121, 122, 12
3, 124,. . . By repeating the same operation for, the next horizontal scan is completed.

(Explanation of Projection Display Device) FIG. 12 shows a configuration example of a data projector as an example of a projection display device in which the active matrix liquid crystal display device having the above configuration is applied as a light valve as an example of electronic equipment. ing.

In FIG. 12, 40 is a light source such as a halogen lamp, 41 is a parabolic mirror, 42 is a heat ray cut filter, 43, 45 and 46 are blue reflection, green reflection, respectively.
Red-reflective dichroic mirrors, 44 and 47 are reflection mirrors, 48, 49 and 50 are light valves composed of the active matrix type liquid crystal display device of the above embodiment, 53 is a dichroic prism, and 55 is a control device. Figure 1
The image signal, clock signal, and various control signals supplied from the outside to the active matrix type liquid crystal display device shown in FIG.

In the data projector of this embodiment, the white light emitted from the light source 40 is condensed by the parabolic mirror 41, passes through the heat ray cut filter 42, blocks the infrared rays, and only visible light is emitted. The light enters the blue reflection dichroic mirror 43. First, blue light (generally 500) is reflected by the blue reflecting dichroic mirror 43.
nm or less) and other light (yellow light) is transmitted. The reflected blue light changes its direction by the reflection mirror 44 and enters the blue modulation light valve 48.

On the other hand, the light transmitted through the blue reflecting dichroic mirror 43 is reflected by the green reflecting dichroic mirror 45.
, And green light (having a wavelength of approximately 500 to 600 nm) is reflected, and other red light (having a wavelength of approximately 600 nm or more) is transmitted. The green light reflected by the green reflecting dichroic mirror 45 enters a green modulation light valve 49. The red light transmitted through the green reflecting dichroic mirror 45 is converted into a red reflecting dichroic mirror 46,
The direction is changed by the reflection mirror 47 and the light enters the red modulation light valve 50.

The light valves 48, 49 and 50 are respectively driven by blue, green and red primary color signals supplied from a signal processing circuit (not shown), and light incident on each light valve is modulated by each light valve. Thereafter, the light is synthesized by the dichroic prism 53. Dichroic prism 5
3 is formed so that the red reflection surface 52 and the blue reflection surface 51 intersect each other. Then, the color image synthesized by the dichroic prism 53 is enlarged and projected on the screen by the projection lens 54 and displayed.

[0051]

As a result, a plurality of pixel electrodes can be selected by the same scanning line and the same data line, so that the number of data lines or scanning lines can be reduced and the aperture ratio can be increased. Become.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration example of an active matrix liquid crystal display device to which the present invention is applied.

FIG. 2 is a layout diagram in the vicinity of a pixel of a substrate for an active matrix liquid crystal display device to which the present invention is applied.

FIG. 3 is a timing chart showing an example of operation timing of the active matrix liquid crystal display device shown in FIG.

FIG. 4 is an electric characteristic diagram showing an example of electric characteristics of a pixel TFT.

FIG. 5 is a timing chart showing a modification of the operation timing of the active matrix liquid crystal display device shown in FIG.

FIG. 6 is an electrical characteristic diagram showing another example of the electrical characteristics of the pixel TFT.

FIG. 7 is a timing chart showing another modification of the operation timing of the active matrix liquid crystal display device shown in FIG.

FIG. 8 is a timing chart showing another modification of the operation timing of the active matrix liquid crystal display device shown in FIG.

FIG. 9 is a modified example of a layout diagram around a pixel shown in FIG. 2;

FIG. 10 is another modified example of the layout diagram around the pixel shown in FIG. 2;

FIG. 11 is a timing chart showing an example of operation timing in the layout diagram shown in FIG. 10;

FIG. 12 is a schematic configuration diagram of a data projector as an example of a projection display device in which the active matrix liquid crystal display device of the embodiment is applied as a light valve.

FIG. 13 is a block diagram illustrating a configuration example of an active matrix liquid crystal display device.

FIG. 14 is a layout diagram in the vicinity of a pixel of a substrate for an active matrix liquid crystal display device.

15 is a timing chart showing an example of operation timing of the active matrix liquid crystal display device shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Shift register circuit 2 Scan line drive circuit 3, 4 Pixel transistor 5 Pixel electrode 6 Contact 10,. . . , 13 sampling transistor 40 lamp 43, 45, 46 dichroic mirror 48, 49, 50 light valve 53 dichroic prism 54 projection lens 55 control device 120,. . . , 123 data lines 200,. . . , 202 scan lines

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G09G 3/20 642 G09G 3/20 642D 680 680C 3/36 3/36 F term (Reference) 2H092 JA24 NA07 NA29 PA08 PA12 RA05 2H093 NC12 NC16 NC34 ND22 NE06 NG02 NG11 5C006 BB16 BC03 BC06 BC12 BF03 BF33 EA01 EB05 EC11 FA54 5C080 AA10 BB05 DD03 DD23 FF11 JJ02 JJ06 5C094 AA05 AA10 AA15 CA04A13A13A18A15A15A15 EA05 EA10 EB02 ED05 FA01 FB12 FB14 FB15 GA10

Claims (7)

[Claims] A plurality of scanning lines; a plurality of data lines intersecting the plurality of scanning lines; a first pixel electrode provided corresponding to an intersection of the plurality of scanning lines and the plurality of data lines; A first switching element for connecting the data line to the first pixel electrode; a second switching element for connecting the data line to the second pixel electrode; The switching element and the second switching element are controlled by the same scanning line, and when a first selection signal is input to the scanning line, the first and second switching units conduct, and a second selection signal Wherein the first switching means is turned on and the second switching means is turned off when is input to the scanning line. 2. A plurality of scanning lines, a plurality of data lines intersecting the plurality of scanning lines, a first pixel electrode provided corresponding to an intersection of the plurality of scanning lines and the plurality of data lines, and A first switching element for connecting the data line to the first pixel electrode; a second switching element for connecting the data line to the second pixel electrode; The switching element and the second switching element are controlled by the same scanning line. When a first selection signal is input to the scanning line, the first and second switching units are turned on, and the second switching unit is turned off. The electro-optical device according to claim 1, wherein when the second selection signal is input to the scanning line, the second switching unit is turned on and the first switching unit is turned off. 3. The switching element is an N-type or P-type switching element.
2. A thin film transistor of a type.
Or the electro-optical device according to 2. 4. A plurality of scanning lines, a plurality of data lines intersecting the plurality of scanning lines, a first pixel electrode provided corresponding to an intersection of the plurality of scanning lines and the plurality of data lines, and Driving an electro-optical device having a second pixel electrode, a first switching element connecting the data line to the first pixel electrode, and a second switching element connecting the data line to the second pixel electrode A driving method of the electro-optical device, wherein the first switching element and the second switching element are controlled by the same scanning line, and a first selection signal is input to the scanning line to thereby control the first and second switching elements. The second switching means is turned on, and a second selection signal is input to the scanning line, whereby the first switching means is turned on and the second switching means is turned off. The driving method of the academic apparatus. 5. A plurality of scanning lines, a plurality of data lines intersecting the plurality of scanning lines, a first pixel electrode provided corresponding to an intersection of the plurality of scanning lines and the plurality of data lines, and Driving an electro-optical device having a second pixel electrode, a first switching element connecting the data line to the first pixel electrode, and a second switching element connecting the data line to the second pixel electrode A driving method for the electro-optical device, wherein the first switching element and the second switching element are controlled by the same scanning line, and a first selection signal is input to the scanning line, whereby the first switching is performed. Means, the second switching means is non-conductive, and a second selection signal is input to the scanning line, so that the second switching means is conductive, and the first switching means is turned on. A method for driving an electro-optical device, wherein the means is made non-conductive. 6. An electronic apparatus, comprising: the electro-optical device according to claim 1; and a control device that controls the optical device. 7. A light source, an electro-optical device according to claim 6, wherein the light from the light source is modulated and transmitted, and projection optical means for condensing the light modulated by the electro-optical device and projecting the light enlarged. A projection type display device comprising: