JP2006091061A - Electrooptical apparatus, driving method for same, and electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrooptical apparatus capable of preventing the occurrence of noise and a sandstorm phenomenon on a display screen without changing a sequence at the time of power on/off of the electrooptical apparatus. <P>SOLUTION: The electrooptical apparatus 1 comprises; a backlight 50; an element substrate 151 including a plurality of scanning lines, a plurality of data lines and a plurality of pixel circuits provided according to intersections of the scanning lines and the data lines; an opposing substrate 152 which is provided at the position opposing to the element substrate 151; a liquid crystal 155 which is provided between the element substrate 151 and the opposing substrate 152, for controlling light from the back light 50. The pixel circuit includes a volatile memory and a solar battery 413 for generating power by receiving light from the back light 50 and for supplying the generated power to the volatile memory. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to, for example, an electro-optical device, a driving method of the electro-optical device, and an electronic apparatus.

Conventionally, electro-optical devices such as liquid crystal display devices are known. The electro-optical device includes, for example, a first substrate, a second substrate provided to face the first substrate, and a liquid crystal provided between the first substrate and the second substrate. And a backlight provided on the opposite side of the first substrate from the second substrate.
The first substrate includes a plurality of scanning lines, a plurality of data lines, and a plurality of pixel circuits provided corresponding to the intersection of the scanning lines and the data lines. A common electrode is provided on the first substrate side of the second substrate. These scanning lines, data lines, pixel circuits, and common electrodes are connected to a control circuit (see Patent Document 1).

  The pixel circuit includes a first transfer gate connected to the scanning line and the data line, a volatile memory connected to the first transfer gate, a second transfer gate connected to the volatile memory and the control circuit, and a second transfer gate. A pixel electrode connected to the gate is included.

In this pixel circuit, when the scanning line signal from the scanning line becomes active, the data line signal is taken in from the data line. The fetched data line signal is stored in the volatile memory, and the second transfer gate is turned on. Then, the polarity signal or the opposite polarity signal from the control circuit is taken into the pixel electrode through the second transfer gate.
JP 2004-86152 A

  By the way, in the above electro-optical device, when the power is turned on, the backlight is turned on and then the pixel circuit is turned on in order to prevent burning of the display screen and noise. Further, when the power is turned off, the backlight power is turned off after the pixel circuit is turned off.

  Therefore, in the above-described electro-optical device, when the power is turned on, there is a time from when the backlight is lit until a signal is supplied to the pixel circuit, so that the light from the backlight is not controlled. There is a possibility that noise or sandstorm may occur on the display screen because the electro-optical material is transmitted. In addition, when the power is turned off, the light from the backlight passes through the electro-optic material even after the power of the pixel circuit is turned off and the electro-optic material is not controlled. There was a risk of storms.

  An object of the present invention is to provide an electro-optical device, a driving method of the electro-optical device, and an electronic device that can prevent noise, sandstorm, and the like from being generated on a display screen without changing the sequence when the electro-optical device is turned on / off. Is to provide equipment.

  The electro-optical device of the present invention includes a light source, a plurality of scanning lines, a plurality of data lines, and a first substrate having a plurality of pixel circuits provided corresponding to the intersections of the scanning lines and the data lines. A second substrate provided opposite to the first substrate, and an electro-optical material provided between the first substrate and the second substrate for controlling light from the light source, The pixel circuit includes a volatile memory, and includes a photoelectric conversion element that receives light from the light source to generate electric power and supplies the generated electric power to the volatile memory. And

  Here, the electro-optical material is a material whose optical characteristics such as transmittance and luminance change when an electric signal (current signal and voltage signal) is supplied, and examples thereof include liquid crystal. The electro-optical device is a device including the electro-optical material. Therefore, it goes without saying that the present invention can be applied to other display devices having an electro-optic effect of controlling light from a light source by changing an optical characteristic such as a refractive index by applying an electric field. One photoelectric conversion element may be provided for each pixel circuit, or one photoelectric conversion element may be provided for a plurality of pixel circuits.

  According to this invention, the photoelectric conversion element that receives light from the light source to generate electric power and supplies the generated electric power to the volatile memory of the pixel circuit is provided. Therefore, when the power is turned off, the operation when the power is turned on is as follows. When the power is turned off, the power of the pixel circuit is first turned off. In this state, since the backlight is lit, the volatile memory holds the contents by the power supplied from the photoelectric conversion element. . Thereafter, when the power of the backlight is turned off, power is not supplied from the photoelectric conversion element to the volatile memory, so that the contents of the volatile memory are erased and the electro-optical material is reset. As a result, the potentials of all the pixel electrodes become equal, and the display screen becomes uniform. After that, even if the power is turned on, the electro-optic material is reset, so that the light from the backlight passes through the reset electro-optic material, and noise and sandstorms are generated. Can be prevented.

  Therefore, it is possible to prevent the occurrence of noise, sandstorm, and the like automatically without changing the sequence when the electro-optical device is turned on / off. Further, if the position of the photoelectric conversion element is adjusted as appropriate, power can be supplied to the volatile memory using unnecessary light emitted from the backlight without newly providing a power supply circuit, which is economical. .

  Moreover, it is preferable that the said photoelectric conversion element is provided under the light-shielding area | region which prevents incidence | injection of external light. Here, the light shielding region may be formed in the electro-optical device, or may be formed in a housing in which the electro-optical device is accommodated. Under the light-shielding region, external light is prevented from entering, but light from the light source is incident. Therefore, when a photoelectric conversion element is provided under the light-shielding region, the photoelectric conversion element can be reliably operated based only on / off of the light source regardless of external light. Further, since the photoelectric conversion element can operate by receiving unnecessary light from the light source, electric power can be effectively utilized.

  In addition, it is preferable that a display area including a plurality of pixels corresponding to the pixel circuit is provided, and the light shielding area is provided around the display area. In this case, unnecessary light from the light source can be received more reliably and effectively used.

  The photoelectric conversion element is preferably formed in the pixel circuit. In order to supply electric power from the photoelectric conversion element to the pixel circuit, it is necessary to wire power supply lines for supplying the VDD and VSS potentials from the photoelectric conversion element to the respective pixel circuits. Therefore, when the photoelectric conversion element is formed in the pixel circuit, a power supply line for supplying at least one potential can be arranged in the pixel circuit, and thus at least one wiring reaching the pixel circuit can be reduced.

  Furthermore, it is preferable that the photoelectric conversion element is formed on the first substrate. In this case, for example, the photoelectric conversion element can be formed on the same substrate as the thin film transistor constituting the pixel circuit or the peripheral driver circuit in the same process. As a result, since the photoelectric conversion element can be built in a so-called TFT substrate, the process of the electro-optical device can be simplified and the number of components can be reduced.

According to another aspect of the invention, an electronic apparatus includes the above-described electro-optical device.
In addition, the driving method of the electro-optical device according to the invention includes a light source, a plurality of scanning lines, a plurality of data lines, and a plurality of pixel circuits provided corresponding to intersections of the scanning lines and the data lines. A first substrate, a second substrate provided opposite to the first substrate, and an electricity provided between the first substrate and the second substrate for controlling light from the light source The pixel circuit includes a volatile memory, causes the photoelectric conversion element to receive light from the light source, generates electric power, and generates the generated electric power as the volatile memory. The volatile memory is driven by supplying to the volatile memory.

<1. First Embodiment>
FIG. 1 is a perspective view showing a configuration of an electro-optical device 1 according to the first embodiment of the present invention, and FIG. 2 is a ZZ ′ cross-sectional view in FIG. The electro-optical device 1 is accommodated in a housing 300 (indicated by a broken line in FIG. 2). The electro-optical device 1 includes an element substrate 151 as a first substrate on which the pixel electrode 406 and the like are formed, and a counter substrate as a second substrate that is disposed opposite to the element substrate 151 and on which the common electrode 158 and the like are formed. 152, a liquid crystal 155 as an electro-optical material provided between the element substrate 151 and the counter substrate 152, and a liquid crystal 155 which is provided below the element substrate 151 (on the side opposite to the counter substrate 152) and irradiates light. And a backlight 50 as a light source. The element substrate 151 is formed of glass, a semiconductor, or the like, and various circuits and the like are formed on the element substrate 151 using TFTs (Thin Film Transistors). The counter substrate 152 is formed of a transparent material such as glass.

  A seal member 154 that seals the gap between the element substrate 151 and the counter substrate 152 is provided on the outer periphery of the counter substrate 152. The seal member 154 forms a space in which the liquid crystal 155 is sealed together with the element substrate 151 and the counter substrate 152. A spacer 153 is mixed in the seal member 154 in order to maintain a distance between the element substrate 151 and the counter substrate 152. Note that an opening for sealing the liquid crystal 155 is formed in the seal member 154, and the opening is sealed with a sealing material 156 after the liquid crystal 155 is sealed.

  Here, a decoding circuit 300A for driving a data line (described later) extending in the Y direction is formed on the surface of the element substrate 151 on the counter substrate 152 side and outside one side of the seal member 154. Further, a plurality of connection electrodes 157 are formed on one side, and various signals and image signals from a control circuit described later are input through the connection electrodes 157. Further, on both sides of the one side of the seal member 154, a scanning line driving circuit 100 for driving a scanning line, which will be described later, extending in the X direction is formed.

  FIG. 3 is a partial plan view of the counter substrate 152 constituting the electro-optical device 1. On the surface of the counter substrate 152 facing the element substrate 151, a display region 152A configured by arranging a plurality of pixels, and a light shielding region 152B provided around the display region 152A to prevent the incidence of external light. A light shielding region 152C provided in the gap between the pixels in the display region 152A is formed (see FIG. 2).

  The light-shielding region 152B prevents external light from entering, and surrounds the display region 152A at the inner peripheral edge and extends to the edge of the counter substrate 152. Specifically, the light shielding region 152B is configured by a black matrix that is a film body. The black matrix is formed of various materials having a light shielding property, such as a single metal such as chromium, an alloy containing the single metal as a main component, or a resin material colored black by dispersion of carbon black. The display area 152A is composed of color filters. The color filter has three colors of R (red), G (green), and B (blue) corresponding to sub-pixels described later. The light shielding region 152C has the same configuration as the light shielding region 152B, and is formed in the gap between the subpixels in order to prevent the incidence of external light and the light leakage of the backlight 50. One solar cell 413 as a photoelectric conversion element described later is provided on the counter substrate 152 side of the element substrate 151 and below the light shielding region 152B.

  Although not shown, a protective film is formed on the above color filter and black matrix, and a common electrode 158 is formed on the protective film. The common electrode 158 is electrically connected to the element substrate 151 via a conductive material provided in at least one of the four corners of the element substrate 151. In addition, an alignment film or the like that has been rubbed in a predetermined direction is provided on the opposing surface side of the element substrate 151 and the opposing substrate 152, and a polarizing plate that corresponds to the alignment direction is provided on each back surface side. .

  The backlight 50 includes two edge lights 51 and a planar light guide plate 52 that emits surface light from the light emitted from the edge lights 51. The edge light 51 is a rod-shaped cold cathode fluorescent tube. Although not shown, a prism sheet is provided on the element substrate 151 side of the planar light guide plate 52 in order to improve luminance, and diffusion for diffusing light emitted from the edge light 51 is provided on the prism sheet. A plate is provided. A reflective plate is provided on the opposite side of the planar light guide plate 52 from the element substrate 151.

  FIG. 4 is a block diagram illustrating a schematic configuration of the electro-optical device 1. The electro-optical device 1 includes a display panel AA and a control circuit 600. The control circuit 600 generates various control signals and image signals Dr, Dg, Db. These image signals Dr, Dg, and Db are binary signals. The control signal includes a common potential VCOM, a polarity signal FR, and an inverted polarity signal FRX. Among these control signals, the common potential VCOM is a signal that is supplied to the common electrode and is inverted in one frame cycle. The polarity signal FR is a signal synchronized with the common potential VCOM. The inverted polarity signal FRX is a signal obtained by inverting the polarity signal FR. The above control signals and image signals Dr, Dg, Db are taken into the display panel AA through a plurality of input terminals formed at the end of the display panel AA.

  Specifically, the display panel AA includes a display area A, a scanning line driving circuit 100, a sampling circuit 200A, and a decoding circuit 300A. Among these, in the display area A, n sets of scanning lines 101 and 102 are formed in parallel with the X direction, and 3 m data lines 103 are formed in parallel with the Y direction orthogonal to the X direction. In the display area A, pixel circuits 400 are provided corresponding to the intersections of the scanning lines 101 and 102 and the data lines 103, respectively. A signal supply line (not shown) is formed in the display area A, and the polarity signal FR and the inverted polarity signal FRX are supplied to each pixel circuit 400 via the signal supply line.

  The scanning line driving circuit 100 generates scanning signals Vg1, Vg2, Vg3,..., Vgn and inverted scanning signals Vg1X, Vg2X, Vg3X,. The scanning signals Vg1 to Vgn are generated by sequentially transferring the Y transfer start pulse SPY in synchronization with the Y clock signal CLKY. The inverted scanning signals Vg1X, Vg2X, Vg3X,..., Vgn are obtained by inverting the logic levels of the scanning signals Vg1, Vg2, Vg3,.

  The scanning signal Vg1 is a pulse having a width corresponding to one horizontal scanning period (1H) from the first timing of one vertical scanning period (1F), and is supplied to the scanning line 101 in the first row. Thereafter, the pulses are sequentially shifted and supplied as scanning signals Vg2, Vg3,..., Vgn to the scanning lines 101 in the second, third,. In general, when the scanning signal Vgi supplied to the scanning line 101 in the i-th row (i is an integer satisfying 1 ≦ i ≦ n) becomes H level, the scanning line 101 is selected.

  The pixel circuit 400 is a sub pixel corresponding to any one of the R color, the G color, and the B color, and one pixel is configured by the R color, the G color, and the B color sub pixels. In FIG. 1, the symbols [R] [G] [B] shown in the pixel circuit 400 correspond to the R color, G color, and B color. The sampling circuit 200A includes m sampling units 20U, and one sampling unit 20U corresponds to one pixel. The decode circuit 300A decodes the address signal ADR to generate a decode signal. This decode signal is composed of selection signals d1 to dm. The selection signals d1 to dm are signals that designate one pixel.

  FIG. 5 is a circuit diagram showing a configuration of the decode circuit 300A. In the following description, it is assumed that the display area A is configured by 2 rows and 15 columns in order to simplify the description. In this case, one row is composed of 5 pixels, and m = 5. Since the address signal ADR needs to designate the selection of one pixel from among the five pixels, 3-bit addressing is required. For this reason, the address signal ADR is composed of bit0, bit0X, bit1, bit1X, bit2, and bit2X, and the number of bits N is 3. Note that bit0X, bit1X, and bit2X are signals obtained by inverting bit0, bit1, and bit2.

  The decoding circuit 300A includes three-input NAND circuits 301, 302, 303, 304, and 305. NAND circuits 301 to 305 output selection signals d1 to d5 that become active (L level) when the address value designated by the address signal ADR is 0 to 4, respectively. For example, the NAND circuit 301 sets the logic level of the selection signal d0 to L level when all of bit0X, bit1X, and bit2X are “1”. That is, when the address value designated by the address signal ADR is “0”, the selection signal d1 that is active at the L level is generated.

  FIG. 6 is a circuit diagram showing a configuration of the sampling unit 20U. The sampling unit 20U is supplied with a selection signal d1 corresponding to the first pixel. The other sampling units 20U are configured similarly. The sampling unit 20U includes a subunit 20R corresponding to the R color, a subunit 20G corresponding to the G color, and a subunit 20B corresponding to the B color. The subunits 20R, 20G, and 20B are supplied with image signals Dr, Dg, and Db from the control circuit 600 through image signal supply lines Lr, Lg, and Lb.

  Hereinafter, although the subunit 20R will be described, the subunit 20G and the subunit 20B are configured in the same manner as the subunit 20R. The subunit 20R includes a transfer gate 220, a latch circuit including a clocked inverter 231 and an inverter 232, and an inverter 260. When the selection signal d1 becomes active, the subunit 20R samples the image signal Dr supplied via the image signal supply line Lr and takes it into the latch circuit. The sampled image signal Dr is supplied to the data line 103 as the data line signal X1r via the inverter 260. As described above, the image signal Dr is a binary signal, and the data line signal X1r is also a binary signal.

  FIG. 7 is a circuit diagram showing a configuration of the pixel circuit 400. The pixel circuit 400 is located in the first row and the first column, and is opposed to the transfer gate 401, the volatile memory 410 including the inverters 402 and 403, the transfer gates 404 and 405, and the common electrode of the counter substrate. And a pixel electrode 406.

  FIG. 8 is a circuit diagram at the transistor level including the power source of the volatile memory 410. The inverters 402 and 403 of each volatile memory 410 are each composed of two complementary MOS transistors, and power is supplied to the inverters 402 and 403 from the solar cell 413 described above.

  The common electrode is supplied with a common potential VCOM whose polarity is inverted at the frame period. That is, if the common potential VCOM becomes high in a certain frame, the common potential VCOM becomes low in the next frame. Therefore, a voltage corresponding to the potential difference between the pixel electrode 406 and the common potential VCOM is applied to the liquid crystal.

  When the scanning signal Vg1 and the inverted scanning signal Vg2 supplied via the scanning lines 101 and 102 become active, the transfer gate 401 takes in the data line signal X1r supplied via the data line 103. The inverters 402 and 403 operate as a storage circuit and store the logic level of the captured data line signal X1r.

  The transfer gate 404 is turned on when the logic level of the connection point P1 is H level, and is turned off when the logic level of the connection point P1 is L level. On the other hand, the transfer gate 405 is turned on when the logic level of the connection point P1 is L level, and is turned off when the logic level of the connection point P1 is H level. Therefore, when the data line signal X1r is at the H level, the inverted polarity signal FRX is taken into the pixel electrode 406 via the transfer gate 404. On the other hand, when the data line signal X1r is at the L level, the polarity signal FR is taken into the pixel electrode 406.

  Here, the polarity signal FR and the common potential VCOM have the same polarity, and the inverted polarity signal FRX and the common potential VCOM have opposite polarities. Therefore, if the logic level of the data line signal X1r is H level, a potential of the inverted polarity signal FRX having a polarity opposite to the common potential VCOM is generated in the pixel electrode 406, and as a result, a voltage is applied to the liquid crystal layer of the pixel. The On the other hand, if the logic level of the data line signal X1r is L level, a potential of the polarity signal FR having the same polarity as the common potential VCOM is generated in the pixel electrode 406. As a result, no voltage is applied to the liquid crystal layer of the pixel. In the present embodiment, the liquid crystal layer employs normally white display. Therefore, “black” is displayed when the data line signal X1r is at the H level, and “white” is displayed when the data line signal X1r is at the L level.

  According to the pixel circuit 400, the written logic level can be continuously held by the memory circuit. Therefore, when displaying a still image, the operation of the sampling circuit 200A can be stopped to reduce power consumption. However, if a voltage having the same polarity is continuously applied to the liquid crystal layer, the characteristics are deteriorated. Therefore, it is necessary to reverse the voltage polarity of the liquid crystal layer. Therefore, the common potential VCOM, the polarity signal FR, and the inverted polarity signal FRX are inverted every frame.

When the electro-optical device 1 is turned off, the operation when the power is turned on is as follows. When the power of the electro-optical device 1 is turned off, first, the power of the pixel circuit 400 is turned off. In this state, since the backlight 50 is lit, the volatile memory is powered by the power supplied from the solar cell 413. 410 holds the contents. Thereafter, when the power of the backlight 50 is turned off, no power is supplied from the solar cell 413 to the volatile memory 410, so the contents of the volatile memory 410 are erased and the liquid crystal 155 is reset. As a result, the potentials of all the pixel electrodes 406 become equal, and the display screen becomes uniform.
After that, even when the power is turned on, the liquid crystal 155 is reset, so that light from the backlight 50 is transmitted through the reset liquid crystal 155 to prevent noise, sandstorms, and the like from occurring. it can.

  FIG. 9 is a timing chart for explaining the operation of the electro-optical device. In this example, a display area A of 2 rows and 15 columns (5 pixels) is assumed. As shown in FIG. 10, black (shaded portion) is displayed on the first row and white is displayed on the second row. To do. In the first half writing frame shown in FIG. 6, the image signals Dr, Dg, and Db are written to the pixel circuit 400, and the writing operation is not performed in the second holding frame. That is, it is assumed that there is no change in the image in the holding frame. Since the display area A in this example is composed of two rows, one frame period is composed of two horizontal periods, but the present invention is not limited to this and may be composed of a large number of horizontal periods. .

  The address signal ADR changes its address value from 0 to 4 in one horizontal period. Thereby, five pixels are designated. In one horizontal period of the first half of the writing frame, since the image signals Dr, Dg, and Db are at the H level, the inverted polarity signal FRX is selected, and the pixel electrode 406 of each pixel circuit 400 in the first row and the first column. Becomes a low potential. At this time, since the common potential VCOM is a high potential, the applied voltage VL (1, 1) of the liquid crystal is a negative voltage −ΔV with respect to the potential of the pixel electrode 406. As described above, since the liquid crystal of the present embodiment is normally white display, black is displayed when a voltage is applied. When the common potential VCOM is inverted in the holding frame, the inversion polarity signal FRX is also inverted, so that black is also displayed in the holding frame.

  According to this embodiment, there are the following effects. Since the solar cell 413 that receives light from the backlight 50 and generates power in the electro-optical device 1 and supplies the generated power to the volatile memory 410 is provided, the sequence when the electro-optical device 1 is turned on / off is changed. It is possible to prevent the occurrence of noise, sandstorm, etc. automatically without changing. In addition, if the position of the solar cell 413 is adjusted as appropriate, power can be supplied to the volatile memory 410 using unnecessary light emitted from the backlight 50 without newly providing a power supply circuit. It is.

  In addition, since the solar cell 413 is provided under the light shielding region 152B, the solar cell 413 can be reliably operated based only on / off of the backlight 50 regardless of external light. In addition, since the solar cell 413 can operate by receiving unnecessary light from the backlight 50, power can be effectively utilized.

  In addition, since the solar cell 403 is formed on the counter substrate 152 side of the element substrate 151, the solar cell 403 can be formed on the same substrate as the thin film transistors constituting the pixel circuit 400 and the peripheral driver circuit, for example, in the same process. As a result, since the solar cell 403 can be built in a so-called TFT substrate, the process of the electro-optical device 1 can be simplified and the number of components can be reduced.

<2. Second Embodiment>
In the present embodiment, the configuration of the solar cell 413A is different from that of the first embodiment. In the following description of the embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted or simplified. FIG. 11 is a plan view of the counter substrate 152 constituting the electro-optical device 1A according to the second embodiment of the present invention. That is, one solar cell 413A is provided in each pixel circuit on the element substrate under the light shielding region 152C.

  Therefore, according to this embodiment, there are the following effects. Since the solar cell 413A is formed in the pixel circuit 400, a power supply line for supplying at least one potential can be arranged in the pixel circuit 400. Therefore, at least one wiring reaching the pixel circuit 400 can be reduced.

<3. Modification>
The present invention is not limited to the above-described embodiment, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention. For example, in each of the embodiments described above, the present invention is applied to the electro-optical device 1 using the liquid crystal 155 as the electro-optical material. . For example, an electrophoretic display panel using a microcapsule containing a colored liquid and white particles dispersed in the liquid as an electro-optical material, and a twist ball that is separately applied to different colors for areas of different polarity Various electro-optical devices such as a twist ball display panel used as an electro-optical material, a toner display panel using black toner as an electro-optical material, or a plasma display panel using a high-pressure gas such as helium or neon as an electro-optical material. In contrast, the present invention can be applied similarly to the above embodiment.

  In each of the above embodiments, the backlight 50 is used as a light source. However, the present invention is not limited to this, and a reflective liquid crystal display device may be configured using a front light. Further, in each of the embodiments, the solar cells 413 and 413A are formed on the counter substrate 152 side of the element substrate 151. However, the present invention is not limited to this, and may be formed between the element substrate 151 and the backlight 50. In each of the above embodiments, the solar cells 413 and 413A are formed under the light shielding regions 152B and 152C. However, the present invention is not limited to this, and any location can be used as long as the light from the backlight 50 can be received. A light-shielding region may be provided, and a solar cell may be provided inside the light-shielding region of the housing 300.

  In each of the above embodiments, the present invention is applied to the pixel circuit as shown in FIG. 7, but the present invention is not limited to this. For example, the present invention is applied to a pixel circuit having a first transistor, a volatile memory, and a pixel electrode. May be. Here, each pixel includes a pixel electrode, a counter electrode formed on a counter substrate, and a liquid crystal provided between these electrodes. This pixel circuit is arranged near the intersection of the scanning line and the data line, the gate of the first transistor is connected to the scanning line, the source is connected to the data line, and the drain is connected to the pixel electrode. Further, a volatile memory is connected between the drain of the first transistor and the pixel electrode.

<4. Application example>
Next, electronic devices to which the electro-optical device 1 according to the above-described embodiments and modifications are applied will be described. FIG. 12 is a perspective view illustrating a configuration of a mobile personal computer to which the electro-optical devices 1 and 1A are applied. The personal computer 2000 includes the electro-optical device 1 as a display unit and a main body 2010. The main body 2010 is provided with a power switch 2001 and a keyboard 2002.

  FIG. 13 is a perspective view illustrating a configuration of a mobile phone to which the electro-optical devices 1 and 1A are applied. A cellular phone 3000 includes a plurality of operation buttons 3001, scroll buttons 3002, and the electro-optical device 1 as a display unit. By operating the scroll button 3002, the screen displayed on the electro-optical device 1 is scrolled.

  FIG. 14 is a perspective view showing a configuration of a portable information terminal (PDA: Personal Digital Assistants) to which the electro-optical devices 1 and 1A are applied. The information portable terminal 4000 includes a plurality of operation buttons 4001, a power switch 4002, and the electro-optical device 1 as a display unit. When the power switch 4002 is operated, various types of information such as an address book and a schedule book are displayed on the electro-optical device 1.

  Note that electronic devices to which the electro-optical device 1 is applied include digital still cameras, liquid crystal televisions, viewfinder type, monitor direct-view type video tape recorders, car navigation devices, pagers, and electronic devices in addition to those shown in FIGS. Examples include a notebook, a calculator, a word processor, a workstation, a videophone, a POS terminal, and a device equipped with a touch panel. The electro-optical device described above can be applied as the display unit of these various electronic devices.

1 is a perspective view illustrating a configuration of an electro-optical device according to a first embodiment of the invention. It is ZZ 'sectional drawing in FIG. 2 is a partial plan view of a counter substrate of the same electro-optical device. FIG. FIG. 2 is a block diagram illustrating a schematic configuration of the electro-optical device. It is a circuit diagram which shows the structure of the decoding circuit of the same electro-optical device. It is a circuit diagram which shows the structure of the sampling unit of the same electro-optical device. FIG. 3 is a circuit diagram illustrating a configuration of a pixel circuit of the electro-optical device. 2 is a transistor level circuit diagram of a volatile memory of the same electro-optical device. FIG. 6 is a timing chart for explaining the operation of the electro-optical device. It is a figure for demonstrating an example of the display pattern of the display area. FIG. 6 is a plan view of a counter substrate of an electro-optical device according to a second embodiment of the invention. FIG. 14 is a perspective view illustrating a configuration of a mobile personal computer to which the above-described electro-optical device is applied. It is a perspective view which shows the structure of the mobile telephone to which the electro-optical device mentioned above is applied. It is a perspective view which shows the structure of the information portable terminal to which the electro-optical device mentioned above is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1A ... Electro-optical device, 50 ... Backlight (light source), 101 ... Scanning line, 103 ... Data line, 151 ... Element board | substrate (1st board | substrate), 152B, 152C ... Light-shielding area, 152 ... Opposite board | substrate (1st) 2 substrate), 152A ... display region, 155 ... liquid crystal (electro-optical material), 400 ... pixel circuit, 410 ... volatile memory, 413, 413A ... solar cell (photoelectric conversion element).

Claims (7)

A first substrate having a light source, a plurality of scanning lines, a plurality of data lines, and a plurality of pixel circuits provided corresponding to the intersections of the scanning lines and the data lines, and facing the first substrate An electro-optic device comprising: a second substrate provided; and an electro-optic material provided between the first substrate and the second substrate to control light from the light source,
The pixel circuit includes a volatile memory,
An electro-optical device comprising: a photoelectric conversion element that receives light from the light source to generate electric power and supplies the generated electric power to the volatile memory.   The electro-optical device according to claim 1, wherein the photoelectric conversion element is provided under a light-shielding region that prevents incidence of external light. A display area comprising a plurality of pixels corresponding to the pixel circuit;
The electro-optical device according to claim 2, wherein the light shielding region is provided around the display region.   The electro-optical device according to claim 1, wherein the photoelectric conversion element is formed in the pixel circuit.   The electro-optical device according to claim 1, wherein the photoelectric conversion element is formed on the first substrate.   An electronic apparatus comprising the electro-optical device according to claim 1. A first substrate having a light source, a plurality of scanning lines, a plurality of data lines, and a plurality of pixel circuits provided corresponding to the intersections of the scanning lines and the data lines, and facing the first substrate A driving method of an electro-optical device, comprising: a second substrate provided as a first substrate; and an electro-optical material provided between the first substrate and the second substrate and controlling light from the light source. There,
The pixel circuit includes a volatile memory,
A driving method of an electro-optical device, wherein the photoelectric conversion element receives light from the light source to generate electric power, supplies the generated electric power to the volatile memory, and drives the volatile memory.

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