JP4501637B2 - Electro-optical device, driving circuit thereof, driving method, and electronic apparatus - Google Patents

Description

The present invention relates to a technique for displaying an image using an electro-optic material, and more particularly, to a technique for charging / discharging (precharging) a data line to which a data potential corresponding to a gradation of a pixel is supplied prior to the supply. .

In Patent Document 1, a precharge potential of a level corresponding to a halftone is set immediately before a period in which one scanning line is selected and a data potential (a potential corresponding to the gradation of a pixel) is applied to each data line. A technique for applying all data lines simultaneously is disclosed. According to this configuration, since the amount of charge / discharge when a data potential is applied to each data line can be reduced, display quality deterioration due to charge / discharge when the data potential is applied is suppressed. The Patent Document 2 discloses a precharge potential when a positive data potential is applied and a precharge potential when a negative data potential is applied. The precharge potential corresponding to the negative polarity is set to be asymmetrical with respect to the central potential of the negative data potential and the central potential between the highest and lowest negative data potentials. A configuration with a low potential is disclosed. According to this configuration, even if a charge leak occurs as a result of irradiating light to a switching element (for example, a TFT (Thin Film Transistor) element) that controls a potential applied to the pixel, a vertical leak caused by this is caused. There is an advantage that direction crosstalk (hereinafter referred to as “optical crosstalk”) is suppressed.
Japanese Patent Laid-Open No. 7-295521 (paragraph 0013 and FIG. 1) Japanese Patent Laying-Open No. 2003-202847 (paragraph 0062, paragraph 0063 and FIG. 2)

Incidentally, for example, in an electro-optical device used as a display device connected to a personal computer, a plurality of images having different characteristics may be displayed on one screen. For example, an artificial image such as a window frame or icon (hereinafter referred to as “data-related image”) and a complex image such as a still image or moving image obtained by capturing a natural object (hereinafter referred to as “natural-image-related image”) are simultaneously displayed. It is displayed. Here, the optimum precharge potential differs between the data image and the natural image. However, in the conventional technology, a common precharge potential is applied to all data lines in one period. Since the voltage is applied, the optimum precharge voltage cannot be applied for each image. Therefore, there is a limit in improving the display quality by applying the precharge potential. The present invention has been made in view of such circumstances, and an object thereof is to improve display quality by precharging even when a plurality of images having different characteristics are displayed in a display area.

In order to solve this problem, a first feature of the drive circuit according to the present invention is that a pixel corresponds to each intersection of a plurality of scanning lines and a plurality of data lines divided into blocks every predetermined number. In the circuit for driving the arranged electro-optical device, a scanning line driving circuit for sequentially selecting each of the plurality of scanning lines for each selection period, and for each data output period corresponding to each block in one selection period, For each data line belonging to the block, a data line driving circuit for supplying a data potential corresponding to the gradation of the pixel corresponding to the intersection of the data line and the scanning line selected by the scanning line driving circuit, and for each block In the pre-charge period immediately before the data output period in which the data potential is supplied to the data line of each block and the voltage output circuit that outputs the pre-charge potential of the block in time division, the voltage output circuit Tsu is the precharge potential outputted for click in the provision of the precharge means for supplying to the data lines of the block.
According to this configuration, since the data line is precharged to a separate precharge potential for each block, even when a plurality of images having different characteristics are displayed in the display area, the display quality is effectively improved by the precharge. Can be improved. In addition, the specific form which concerns on a 1st characteristic is later mentioned as 1st Embodiment.

A second feature of the drive circuit according to the present invention is that the electro-optical device has pixels arranged corresponding to each intersection of a plurality of scanning lines and a plurality of data lines divided into blocks every predetermined number. And a scanning line driving circuit that sequentially selects each of the plurality of scanning lines for each selection period, and each of the plurality of data lines in the data output period included in one selection period. A data line driving circuit that supplies a data potential corresponding to the gradation of a pixel corresponding to the intersection of the line and the scanning line selected by the scanning line driving circuit, and a plurality of precharge potentials corresponding to different blocks in parallel The voltage output circuit to output and the pre-output output from the voltage output circuit for the block for the data lines belonging to each of the plurality of blocks in the precharge period immediately before the data output period. In providing the precharge means for supplying over di potential.
Also in this configuration, since the data line is precharged to a separate precharge potential for each block, an effect similar to that of the drive circuit according to the first feature is achieved. Further, the drive circuit according to the first feature requires a configuration (for example, the shift register 52 shown in FIG. 1) that distributes the precharge potential output in time division to the data lines of each block. In contrast,
Since such a configuration can be eliminated in the drive circuit according to the second feature, the configuration of the drive circuit can be simplified (for example, the frame region can be narrowed). A specific form according to the second feature will be described later as a second embodiment.

The present invention is also specified as a drive circuit having both the first feature and the second feature. That is, the third feature of the drive circuit according to the present invention is that the electro-optical device has pixels arranged corresponding to each intersection of a plurality of scanning lines and a plurality of data lines divided into blocks for each predetermined number. A scanning line driving circuit for sequentially selecting each of the plurality of scanning lines for each selection period, and for each data output period corresponding to each of a block group composed of a plurality of blocks in one selection period. A data line driving circuit for supplying, to each data line belonging to the block group, a data potential corresponding to the gradation of the pixel corresponding to the intersection of the data line and the scanning line selected by the scanning line driving circuit; A voltage output circuit for outputting the precharge potential of each block belonging to the group in parallel for each block group in a time division manner, and a data output period in which the data potential is supplied to the data line of each block group In previous precharge period, to the data lines belonging to each block in the block group, in the provision of the precharge means for supplying a precharge potential to the voltage output circuit outputs for that block.
Also in this configuration, since the data line is precharged to a separate precharge potential for each block, an effect similar to that of the drive circuit according to the first feature is achieved. A specific form according to the third feature will be described later as a third embodiment.

The precharge means may be realized as a circuit separate from the data line driving circuit (first to third embodiments to be described later), or may be realized as a circuit integrated with the data line driving circuit ( For example, the configuration of FIG. Further, in the present invention, the “precharge period immediately before the data output period” means a period before a data output period and a period after the data output period before the data output period. However, even if it is “immediately before”, it is not essential that the precharge period and the data output period are completely continuous on the time axis.

In a preferred aspect of the drive circuit according to the first to third features, a determination unit that determines the characteristics of the image displayed by the plurality of pixels for each block is provided, and the voltage output circuit includes:
A potential corresponding to the characteristic determined by the determining unit for each block is output as a precharge potential of the block. According to this aspect, since the data line of the block can be precharged with a precharge potential that matches the characteristics of the image displayed in each block, the optimum precharge potential for the actually displayed image is set. This can be used to further improve the display quality.

In another aspect, the data line driving circuit includes a negative data potential between the first potential and a second potential higher than the first potential (eg, the negative data potential range shown in FIG. 3); Each data is a positive data potential between a third potential higher than the second potential and a fourth potential higher than the third potential (for example, the positive data potential range shown in FIG. 3). The voltage output circuit supplies the potential between the third potential and the fourth potential (for example, the potential VH1 in FIG. 3) in the precharge period immediately before the data output period in which the positive data potential is supplied. ) And the third
One of the potentials lower than the potential (for example, the potential VH2 in FIG. 3) is selected for each block and output as the precharge potential, while the precharge period immediately before the data output period in which the negative data potential is supplied. , A potential between the first potential and the second potential (for example, potential VL1 or potential VL2 in FIG. 3) is output as a precharge potential. The potential between the third potential and the fourth potential and the potential between the first potential and the second potential (particularly, the potential VL1 in FIG. 3) until the potential of each data line reaches the intended data potential. This is suitable as a precharge potential for shortening the time (see Patent Document 1). On the other hand, a potential lower than the third potential and a potential between the first potential and the second potential (particularly, a potential lower than the center potential between the first potential and the second potential, such as the potential VL2 in FIG. 3). ) Is suitable as a precharge potential for suppressing optical crosstalk (see Patent Document 2). If such a potential is selectively output as a precharge potential, the effect of shortening the time until the potential of each data line reaches the intended data potential and the effect of suppressing optical crosstalk are selectively achieved. Can get to.
More specifically, each of these potentials is desirably selected according to the characteristics of the image. In this desirable mode, there is provided determination means for determining whether an image displayed by a plurality of pixels is a natural image type image or a data type image for each block, and the data line driving circuit includes: A negative data potential between the potential and the second potential higher than the first potential; and a positive electrode between the third potential higher than the second potential and the fourth potential higher than the third potential. The data output is supplied to each data line, and the voltage output circuit determines whether the determination means is a natural image image in the precharge period immediately before the data output period in which the positive data potential is supplied. A potential between the third potential and the fourth potential is determined for the determined block, and a potential lower than the center potential of the third potential and the fourth potential is determined for the block determined by the determination means as a data system image, or Lower than 3 potential A potential higher than the central potential of the first potential and the fourth potential is output as the precharge potential of the block, respectively, and in the precharge period immediately before the data output period in which the negative data potential is supplied Is determined as a natural image-based image, a potential between the first potential and the second potential, and a block determined by the determining means as a data-related image is a central potential between the first potential and the second potential. Lower potential,
Each is output as a precharge potential of the block. According to this aspect, when the image is a natural image image, the time until the potential of each data line reaches the expected data potential can be shortened, and the image is a data image. In some cases, optical crosstalk can be effectively suppressed. The relationship between the precharge potential and the image characteristics is selected in this way because the light crosstalk is not so noticeable in the natural image system, so the charge / discharge of the data line should be given priority. This is because the suppression of the optical crosstalk should be given priority in order to make the optical crosstalk particularly apparent in the image.
Note that a natural image is typically an image of natural objects such as landscapes and animals and plants, and focusing on the gradation of each pixel, the gradation of adjacent pixels is often different. Or it is an image which has the characteristic that there are many times when the gradation of each pixel of a continuous image on a time axis is different. On the other hand, a data system image is typically an image such as an icon or a window frame generated by an information processing apparatus such as a personal computer. When attention is paid to the gradation of each pixel, pixels adjacent to each other are displayed. This is an image having a characteristic that the number of times that the gradation is different is small, or the number of times that the gradation of each pixel of the continuous image on the time axis is different is small.

The drive circuit according to the present invention is employed as a circuit for driving a pixel in an electro-optical device. An electro-optical device is a device that uses an electro-optical material. An electro-optical material is a material whose optical characteristics (transmittance and luminance) change when electrical energy is applied. A typical example of the electro-optical material is a liquid crystal, but the present invention is naturally also applied to an electro-optical device using another electro-optical material. This type of electro-optical device is employed as a display device for various electronic devices. Examples of electronic devices to which the present invention is applied include a projection display device and a mobile phone. The first to third features of the present invention are also applied to a method for driving an electro-optical device.

<A: First Embodiment>
First, the configuration of the electro-optical device according to the first embodiment of the invention will be described with reference to FIG.
This electro-optical device is a liquid crystal device in which liquid crystal as an electro-optical material is sealed in a gap between an element substrate and a counter substrate. As shown in the figure, the electro-optical device D1 includes m scanning lines 12 extending in the X direction and connected to the scanning line driving circuit 20, and extending in the Y direction orthogonal to the X direction. 4n data lines 14 connected to the data line driving circuit 40 (m and n are both natural numbers). These data lines 14 are divided into four blocks B in units of n adjacent to each other.
1 to B4. In addition, when it is not necessary to specify any of the blocks B1 to B4, they are simply expressed as “block B”.

A pixel P is disposed at the intersection of the scanning line 12 and the data line 14. Accordingly, these pixels P are arranged in a matrix of m rows × 4n columns across the X and Y directions in the display area Ad. As shown in FIG. 2, one pixel P includes a pixel capacitor 71 and a switching element 73. Among these, the pixel capacitor 71 is a capacitor including a pixel electrode 711 formed on the element substrate, a counter electrode 713 formed on the counter substrate, and a liquid crystal 712 sandwiched between the gaps. On the other hand, the switching element 73 is, for example, an n-channel TFT element formed on the surface of the element substrate. The switching element 73 has a gate electrode connected to the scanning line 12, a source electrode connected to the data line 14, and a drain electrode connected to the pixel electrode 711. Note that a storage capacitor that supplementarily holds a voltage applied to the liquid crystal 712 may be arranged in parallel with the pixel capacitor 71.

The scanning line driving circuit 20 shown in FIG. 1 is a circuit that sequentially selects each of the m scanning lines 12 in each vertical scanning period (1F). More specifically, as shown in FIG. 4, the scanning line driving circuit 20 applies scanning signals Y1, Y2,..., Ym that sequentially become active levels for each selection period (horizontal scanning period) to each scanning line 12. Output to. When the scanning signal Yi (i is an integer satisfying 1 ≦ i ≦ m) becomes an active level, the scanning line 12 in the i-th row is selected, and 4n switching elements 73 connected to the scanning line 12 are simultaneously turned on. It becomes a state. At this time, a potential X (hereinafter referred to as “data potential”) X applied to the data line 14 is held in the pixel capacitor 71 of each pixel P in the i-th row via each switching element 73, and according to this voltage. A gradation corresponding to the data potential X is displayed by changing the alignment direction of the liquid crystal 712 of the pixel capacitor 71. In the electro-optical device D1 according to the present embodiment, when no voltage is applied to the pixel capacitor 71, the gradation of the pixel P becomes white (that is, the brightest gradation), and the larger the voltage applied to the pixel capacitor 71, the higher the pixel. This is a normally white mode display device in which the gradation of P becomes dark.
However, the present embodiment is similarly applied to a normally black mode display device.

In this embodiment, as shown in FIG. 4, each selection period (1H) is divided into four periods (hereinafter referred to as “block periods”) Tb1 to Tb4 corresponding to the total number of blocks B. Each block period Tbk (k is a natural number satisfying 1 ≦ k ≦ 4) is a period from the start point until a predetermined time length elapses (hereinafter referred to as “precharge period”) Tp and an end point of the precharge period Tp. And a period (hereinafter referred to as “data output period”) Td until the end of the block period Tbk. The precharge period Tp of the block period Tbk is a period for applying a precharge potential to the n data lines 14 belonging to the block Bk. Meanwhile, the block period T
The bk data output period Td is a period for sequentially applying the data potential X to each of the n data lines 14 belonging to the block Bk. As described above, in the present embodiment, the precharge is executed for each data line 14 of each block Bk at a separate timing within the selection period. In addition, when it is not necessary to specify any one of the block periods Tb1 to Tb4, it is simply expressed as “block period Tb”.

The data line driving circuit 40 shown in FIG. 1 has the scanning line 1 selected by the scanning line driving circuit 20.
2 is a means for applying the data potential X corresponding to the gradation of each pixel P connected to 2 to each data line 14 in the data output period Td. The data potential X applied to each data line 14 is periodically inverted from one of positive polarity and negative polarity to the other with respect to a predetermined potential (for example, potential applied to the counter electrode 713) VC. Is done. “Positive polarity” is the polarity on the higher side than the potential VC, and “negative polarity” is the polarity on the lower side than the potential VC. As a method for inverting the polarity of the data potential X, for example, a frame inversion method in which the polarity is inverted every vertical scanning period, or a row inversion in which the polarity is inverted every scanning line 12 adjacent to each other (in other words, every selection period). In this embodiment, the case where the latter row inversion method is adopted is assumed.

FIG. 3 is a diagram schematically showing the range of the data potential X. As shown in FIG. As shown in the figure, the positive data potential X is determined according to the gradation of the pixel P from the range from the potential VWH to the potential VH ("positive data potential range" shown in FIG. 3). . The potential VWH is higher than the potential VC, and the potential VH is higher than the potential VWH. On the other hand, the negative data potential X is determined in accordance with the gradation of the pixel P from the range from the potential VL to the potential VWL (“negative data potential range” shown in FIG. 3). The potential VWL is a potential lower than the potential VC, and the potential VL is a potential lower than the potential WL. The potential VH and the potential VL, and the potential VWH and the potential VWL are symmetrical about the potential VC, respectively.

On the other hand, the precharge potential applied to the data line 14 of each block Bk during the precharge period Tp is divided into four potentials (VH1, VL1) according to the image displayed in the block Bk and the polarity of the data potential X. , VH2, VL2). In the present embodiment, when a natural image image is displayed in the block Bk, either the precharge potential VH1 or VL1 is selected according to the polarity of the data potential X, and each data line 14 of the block Bk is selected. When a data system image is displayed in each block Bk, one of the precharge potentials VH2 and VL2 is selected according to the polarity of the data potential X, and each block Bk is selected. It is used for precharging the data line 14. A natural image is an image obtained by photographing a natural object such as a landscape or an animal, and a data image is a linear or artificial image such as an icon or a window displayed on a computer display device. It is a typical image.

The precharge potentials VH1 and VL1 are based on the viewpoint that the time until the potential of the data line 14 reaches the intended data potential X is shortened by charging and discharging the data line 14 prior to the application of the data potential X. (See Patent Document 1). On the other hand, the precharge potentials VH2 and VL2 are selected based on the viewpoint of suppressing optical crosstalk caused by leakage of the switching element 73 due to light irradiation (see Patent Document 2). When displaying an image of a natural image system, the optical crosstalk due to the leakage of the switching element 73 is not so conspicuous. Therefore, from the viewpoint of rapidly changing the potential of the data line 14, in the present embodiment, the natural image system is displayed. Each data line 14 of the block Bk for displaying the image is precharged by the precharge potential VH1 or VL1. on the other hand,
When displaying a data system image, optical crosstalk becomes particularly noticeable in view. In this embodiment, each data line 14 of the block Bk displaying a data system image is connected to the precharge potential VH2 or VL2. Precharged by The relationship between the specific level of each potential and the polarity of the data potential is as follows.

The precharge potential VH1 is applied to each data line 14 of the block Bk on which a natural image image is displayed.
Is a potential applied to these data lines 14 in the precharge period Tp immediately before the positive data potential X is applied. The precharge potential VH1 is a potential within the positive data potential range, and is more preferably selected as a center potential between the potential VH and the potential VWH (that is, a potential for displaying gray in gray on the pixel P). The Further, the precharge potential VL1 is the data line 1 in the precharge period Tp immediately before a negative data potential is applied to each data line 14 of the block Bk on which a natural image image is displayed.
4 is an electric potential applied to 4. The precharge potential VL1 is a potential within the negative data potential range, and is more preferably selected as a center potential between the potential VL and the potential VWH (that is, a potential for displaying gray in gray on the pixel P). The As shown in FIG. 3, the precharge potential VH1 and the precharge potential VL1 are symmetrical with respect to the potential VC.

On the other hand, the precharge potential VH2 is applied to the data lines 14 in the immediately preceding precharge period Tp when a positive data potential is applied to each data line 14 of the block Bk on which the data image is displayed. Potential. For example, the precharge potential VH2 is selected to be the same as or slightly higher than the potential VC, and more preferably lower than the potential VWH. The precharge potential VL2 is applied to these data lines 14 in the precharge period Tp immediately before the negative data potential is applied to each data line 14 of the block Bk on which the data system image is displayed. Potential. The precharge potential VL2 is selected to be lower than the center potential between the potential VWL and the potential VL (that is, the potential VL1 that is the center of the negative data potential range), and more preferably higher than the potential VL. The As shown in FIG. 3, precharge potential VH2 and precharge potential VL2
Is an asymmetric potential around the potential VC.

The control circuit 30 shown in FIG. 1 is a means for controlling the overall operation of the electro-optical device D1, and sends various signals to the scanning line drive circuit 20, the data line drive circuit 40, and the precharge circuit 50. Output. Specific waveforms of signals output from the control circuit 30 to the respective units are as follows. First, as shown in FIG. 4, the precharge pulse PG is a pulse signal that rises at the start point of each selection period, and has a pulse width corresponding to one precharge period Tp. The precharge clock PCK is H in a cycle corresponding to the time length of the block period Tb.
This is a clock signal that fluctuates from one of the level and the L level to the other (that is, a signal whose half cycle corresponds to the time length of the block period Tb), and the inverted precharge clock / PCK inverts the logic level of the precharge clock PCK Signal.

As shown in FIG. 1, the control circuit 30 includes a voltage output circuit 31 that generates a precharge signal Spre and outputs it to the precharge signal line 61. The precharge signal Spre is
As shown in FIG. 4, in each block period Tbk, a signal that becomes a precharge potential corresponding to the block Bk (more specifically, a potential corresponding to the image displayed in the block Bk and the polarity of the data potential X). is there. Therefore, the voltage output circuit 31 is specified as means for outputting the precharge potential corresponding to each block Bk in a time division manner for each block period Tbk (more precisely, the precharge period Tp).

The start pulse DX shown in FIG. 4 is a pulse signal output at the start point of the data output period Td of the first block period Tb1 in each selection period. On the other hand, the clock signal CLX0
The so-called dot clock is a clock signal that changes from one of the H level and the L level to the other in a period corresponding to the time length during which the data potential X is applied to one data line 14 in the data output period Td. . The control signal CTL shown in FIG. 4 is a signal for designating the data output period Td (or precharge period Tp) to the data line driving circuit 40, and is active level from the start point to the end point of the data output period Td. On the other hand, the inactive level (L level) is maintained during the precharge period Tp. Although the details will be described later, the data line driving circuit 40 controls the control signal CTL.
The output of the data potential X to each data line 14 is stopped in a period during which is at the L level (that is, the precharge period Tp).

The image signal Vid is a voltage signal that designates the gradation of each pixel P by time division. The image signal Vid in the present embodiment has a potential corresponding to the gradation of one pixel P in a time length corresponding to a half cycle of the clock signal CLX0. As shown in FIG. 1, image data D is input to the control circuit 30 from an external device. The image data D is digital data that designates the gradation of each pixel P. The control circuit 30 synchronizes the image data D for one screen (one frame) input from an external device and written in the frame memory 33 in synchronization with the clock signal CLX0.
The image signal Vid is generated by performing A / A conversion and appropriately inverting the polarity according to the polarity of the data potential X, and this is output to the image signal line 63.

On the other hand, the control circuit 30 determines, based on the image data D stored in the frame memory 33, whether the image displayed in each block Bk of the display area Ad is a natural image system or a data system. 35. Various known techniques are employed as the determination method, but the control circuit 30 in the present embodiment is adapted to the difference in gradation of adjacent pixels P and the change in gradation of each pixel P over time. Based on this, the characteristics of the image are determined. The details of these determination methods are as follows.

The first method is a method for determining image characteristics according to the frequency with which the gradations of adjacent pixels P in each block Bk are different. The determination circuit 35 selects all the pixels P belonging to one block Bk in order. Then, the determination circuit 35 has one pixel P (hereinafter “
Each time a target pixel P) is selected, whether or not the image data D of each pixel P adjacent to the target pixel P in the X direction and the Y direction is different from the image data D of the target pixel P. Judgment is made and the number of times judged to be different is accumulated. When this process is completed for all the pixels P belonging to the block Bk, the determination circuit 35 compares the accumulated value of the number of times it is determined that the gradations are different with a predetermined threshold value, and the accumulated value sets the threshold value. If it exceeds, it is determined that the image displayed in the block Bk is a natural image, whereas if the accumulated value is below the threshold, the image displayed in the block Bk is a data image. judge. In this determination, a natural image is often different in gradation between adjacent pixels P, and a data image is often continuous in the same gradation over a wide range of pixels P. Based on trends.

The second method is a method for determining image characteristics according to the frequency with which the gradation of each pixel P changes over time. The determination circuit 35 determines whether or not the image data D of each pixel P in a certain frame is different from the image data D of the pixel P in the immediately following frame, and calculates the number of times it is determined that they are different. . Then, the determination circuit 35 compares the number of times that the gradation is determined to be different from a predetermined threshold, and if this number exceeds the threshold, the block B
While it is determined that the image displayed at k is a natural image (particularly a moving image), the image displayed at block Bk is determined to be a data image when it is below the threshold. In this determination, the tone of each pixel P often changes momentarily in a natural image moving image, and the tone of each pixel P often does not change for a long time in a data image. Based on general trends.

As is clear from the above description, even if the image displayed in the block Bk is determined to be a natural image, the natural image does not occupy the entire area of the block Bk. This means that natural images are likely to occupy many parts.
The same applies to the case where the image is determined to be a data image. The determination circuit 35 determines whether the image displayed in each block Bk is a natural image system or a data system by executing the above processing for each block Bk. Then, the voltage output circuit 31 receives the data potential X
When it is determined that a natural image image is displayed in the block Bk in the selection period in which the positive polarity is set to the positive polarity, the precharge signal Spre is set to the precharge potential VH1 in the block period Tbk, while the data system Is determined to be displayed, the precharge signal Spre is set to the precharge potential VH2 in the block period Tbk. Similarly, in the selection period in which the data potential X is negative, when it is determined that the image is a natural image, the block period T
The precharge signal Spre is set to the precharge potential VL1 at bk, and if it is determined that the image is a data image, the precharge signal Spre is set to the precharge potential VL2 at the block period Tbk.

As shown in FIG. 1, the control signal CTL output from the control circuit 30 is branched into two systems. One of these systems is supplied to the data line driving circuit 40, and the other system is input to the AND circuit 651 together with the clock signal CLX0 output from the control circuit 30. The AND circuit 651 outputs a clock signal CLX corresponding to the logical product of both signals. As described above, since the control signal CTL becomes L level in the precharge period Tp, the clock signal CLX output from the AND circuit 651 has a dot clock cycle in the data output period Td as shown in FIG. While the level inversion is repeated, the inversion stops during the precharge period Tp. As shown in FIG. 1, the clock signal CLX and an inverted clock signal / CLX obtained by inverting the logic level by an inverter 652 are input to the data line driving circuit 40.

As shown in FIG. 1, the data line driving circuit 40 includes a sampling circuit 41 and a shift register 42. Among these, the sampling circuit 41 has 4n sampling switches 411 each corresponding to a different data line 14. The drain electrode of each sampling switch 411 is connected to the end of the data line 14 corresponding thereto, and each source electrode is connected in common to the image signal line 63. On the other hand, the shift register 42 has a configuration in which 4n-stage unit circuits 421 corresponding to the total number of data lines 14 are arranged. Each unit circuit 421 uses the start pulse DX supplied from the preceding unit circuit 421 (or the control circuit 30 in the first stage unit circuit 421) as the rising and rising edges of the clock signal CLX and the inverted clock signal / CLX. The data is output to the subsequent unit circuit 421 at the downstream timing. Each unit circuit 4
The signal output from the output terminal 21 is a sampling signal S (S1_1, S1_2,... S1_n, S2
_1,..., S4_n) is supplied to the gate electrode of each sampling switch 411. FIG.
As shown in FIG. 4, the sampling signals Sk_1, Sk_2,..., Sk_n are in the block period Tbk.
In the data output period Td, the active level is sequentially changed to the active level, while the inactive level is maintained in the precharge period Tp in which the clock signal CLX and the inverted clock signal / CLX stop inversion. When the sampling signal Sk_j becomes an active level, the sampling switch 411 in the j-th column belonging to the block Bk is turned on, and the image signal Vid supplied to the image signal line 63 at that time is applied to the data line 14 as the data potential X. Applied.

Of the n sampling switches 411 corresponding to each of the blocks B 1 to B 3, the gate electrode of the sampling switch 411 at the final stage (n-th column) is connected to the output terminal of the AND circuit 44. The AND circuit 44 includes a unit circuit 421 corresponding to each block Bk.
Sampling signal Sk_n output from the nth unit circuit 421 and the control circuit 30.
The control signal CTL output from is input. Therefore, in the precharge period Tp in which the control signal CTL is at the L level, the sampling switch 411 is turned off regardless of the level of the sampling signal Sk_n. According to this configuration, all the sampling switches 411 corresponding to the block Bk can be reliably turned off in the precharge period Tp of the block period Tbk.

On the other hand, the precharge circuit 50 is similar to the data line drive circuit 40 in that it includes a sampling circuit 51.
And a shift register 52. Among these, the sampling circuit 51 has 4n sampling switches 511 each corresponding to a different data line 14. The drain electrode of each sampling switch 511 is connected to the end of the corresponding data line 14 opposite to the data line driving circuit 40, and each source electrode is connected in common to the precharge signal line 61. The On the other hand, the shift register 52 has a configuration in which four unit circuits 521 corresponding to the total number of blocks B are arranged. Each unit circuit 521 uses the precharge pulse PG supplied from the previous unit circuit 521 (or the control circuit 30 in the first stage unit circuit 521) for a time length (corresponding to a half cycle of the precharge clock PCK). That is, it is delayed by the block period Tbk) and output to the next unit circuit 521. The signal input to the k-th unit circuit 521 is supplied to the n sampling switches 511 corresponding to the block Bk as the sampling signal Pk. As shown in FIG. 4, the sampling signal Pk becomes an active level in the k-th precharge period Tp included in one selection period. Therefore, in the k-th precharge period Tp, the n sampling switches 511 corresponding to the block Bk are turned on at the same time, and the precharge signal Spre supplied to the precharge signal line 61 at that time is precharged. The charge potential is applied to all the data lines 14 in the block Bk.

Next, the operation of the electro-optical device D1 will be described with particular attention to the application of the precharge potential.
Now, as shown in FIG. 5, it is assumed that the window W is displayed so as to occupy most of the blocks B2 and B3 in the display area Ad, and a natural image image is displayed in the window W. . In the area outside the window W, icons and other windows are displayed. In this case, the determination circuit 35 determines that a natural image image is displayed in the blocks B2 and B3 and a data image is displayed in the blocks B1 and B4. Therefore, as shown in FIG. 4, the precharge signal Spre becomes the precharge potential VH2 in the block periods Tb1 and Tb4 in the selection period in which the data potential X is positive. Block period T
The precharge potential VH1 is reached at b2 and Tb3.

As a result of supplying such a precharge signal Spre, the precharge circuit 50 executes precharge for each block period Tbk as follows. First, in the precharge period Tp of the block period Tb1, the sampling signal P1 becomes an active level, and the precharge potential VH2 of the precharge signal Spre supplied to the precharge signal line 61 at that time is all data of the block B1. Applied to line 14. At this time, since all the sampling switches 411 corresponding to the block B1 are in the OFF state, the data potential X is not applied to any data line 14 of the block B1. In the precharge period Tp of the block period Tb2, the sampling signal P2 becomes active level and the precharge potential VH1 is applied to all the data lines 14 in the block B2, and similarly in the precharge period Tp of the block period Tb3. The precharge potential VH1 is applied to all data lines 14 in the block B3.
To be applied. In the precharge period Tp of the block period Tb4, the precharge potential VH2 is applied to all the data lines 14 in the block B4. Further, since the data potential X is negative in the next selection period, the potential of the precharge signal Spre changes in the order of VL2->VL1->VL1-> VL2 for each block Bk. Accordingly, all the data lines 14 belonging to the blocks B1 and B4 are precharged potential VL2 corresponding to the data system image.
And all the data lines 14 belonging to the blocks B2 and B3 are precharged to a precharge potential VL1 corresponding to a natural image image. Each precharge period T
As described above, the data potential X is sequentially applied to the data line 14 of each block Bk in the data output period Td sandwiched between p.

As described above, in the present embodiment, the pre-applied to the data line 14 of the block Bk according to the characteristic of the image displayed by each block Bk (whether it is a natural image system or a data system). Since the charge potential changes, even when a plurality of images having different characteristics (for example, the window W and its background shown in FIG. 5) are displayed in the display area Ad, precharging according to the characteristics of the image is performed. Display quality can be improved. In particular, in the present embodiment, the precharge potential VH1 or VL1 is applied to the data line 14 of the block Bk on which a natural image image is displayed, so that the pixel P can be quickly displayed without degrading the display quality. Data can be written, and high-quality display with suppressed optical crosstalk is realized by applying the precharge potential VH2 or VL2 to the data line 14 of the block Bk on which a data image is displayed.

<B: Second Embodiment>
Next, an electro-optical device according to a second embodiment of the invention will be described. In the electro-optical device according to this embodiment, the same elements as those in the first embodiment are denoted by common reference numerals, and the description thereof is omitted as appropriate.

FIG. 6 is a block diagram illustrating the configuration of the electro-optical device according to the present embodiment, and FIG. 7 is a timing chart illustrating the operation of the electro-optical device. As shown in FIG. 7, in the present embodiment, unlike the first embodiment, all 4n data lines in the precharge period Tp from the start point until a predetermined time length elapses in the selection period. 14 are precharged all at once. For this reason, the electro-optical device D2 according to this embodiment does not use the control signal CTL described in the first embodiment with respect to the application of the data potential X to the data line 14. The control circuit 30 outputs a clock signal CLX corresponding to a dot clock (clock signal CLX0 of the first embodiment) and an inverted clock signal / CLX in which the logic level is inverted to the data line driving circuit 40. Therefore, in the data output period Td of each selection period, the sampling switches 411 of the first data line 14 belonging to the block B1 to the sampling switches 411 of the nth data line 14 belonging to the block B4 are precharged. Without turning on the period Tp, the power supply device is sequentially turned on, and the data potential X is applied to each data line 14 via the sampling switch 411 that has been turned on.

Further, the voltage output circuit 31 of the control circuit 30 generates four types of precharge signals Spre1 to Spre4 each corresponding to a different block Bk, and each of them generates a separate precharge signal line 6.
Output to 1. Each precharge signal Sprek has four potentials (VH1, VL1, and VH1, shown in FIG. 3) according to the characteristics of the image displayed in the block Bk and the polarity of the data potential.
VH2 or VL2). However, in this embodiment, all the data lines 14
Are precharged simultaneously, one precharge signal Sprek maintains the same precharge potential from the start point to the end point of the selection period, as shown in FIG. However, the precharge signals Spre1 to Spre4 are essentially required to maintain the precharge potential in the precharge period Tp, and the potentials in other periods are arbitrary.

On the other hand, the precharge circuit 50 includes 4n sampling switches 511 each corresponding to a different data line 14. The drain electrode of each sampling switch 511 is connected to the corresponding data line 14. The n sampling switches 511 corresponding to one block Bk are connected to the precharge signal line 6 to which the precharge signal Sprek is supplied.
1 is commonly connected. Further, the precharge pulse PG output from the control circuit 30 is supplied to the gate electrodes of all the sampling switches 511. The precharge pulse PG has the same waveform as that of the first embodiment, and is a pulse signal that becomes an active level in the precharge period Tp starting from the start point of each selection period, as shown in FIG.

Next, the operation of the electro-optical device D2 will be described with reference to FIG. Here, as in the first embodiment, it is assumed that the image shown in FIG. 5 is displayed in the display area Ad. Therefore, the determination circuit 35 of the control circuit 30 determines that the data system image is displayed in the blocks B1 and B4, and determines that the natural image system image is displayed in the blocks B2 and B3.

In this case, the precharge signal Spre1 corresponding to the block B1 and the precharge signal Spre4 corresponding to the block B4 correspond to data-related images in the selection period (the selection period on the left side in FIG. 7) in which the data potential X is positive. The precharge potential VH2 is maintained and becomes the precharge potential VL2 in the next selection period (the central selection period in FIG. 7) in which the data potential X is negative. On the other hand, the precharge signal Spre2 corresponding to the block B2 and the precharge signal Spre3 corresponding to the block B3 are set to the precharge potential VH1 corresponding to the natural image image during the selection period in which the data potential X is positive. In the selection period in which the data potential X is negative, the precharge potential VL1. Therefore, in the precharge period Tp in which the precharge pulse PG is at the active level, the blocks B1 and B1
Each data line 14 of 4 is precharged to precharge potential VH2 or VL2, while each data line 14 of blocks B2 and B3 is precharged to precharge potential VH1 or VL1.

As described above, also in the present embodiment, since the precharge potential applied to the block Bk is selected according to the image characteristics of each block Bk, the same effect as in the first embodiment can be obtained. Furthermore, in this embodiment, since it is not necessary to provide the precharge period Td for each block Bk, the shift register 52 and the control signal CT described in the first embodiment are used.
L can be eliminated, and there is an advantage that the configuration of the electro-optical device D2 is simplified.

<C: Third Embodiment>
Next, an electro-optical device according to a third embodiment of the invention will be described. The first embodiment exemplifies a configuration in which the potential of the precharge signal Spre of one system becomes the precharge potential of each block Bk in a time division manner. In the second embodiment, the precharge potential of each block Bk is illustrated. A configuration for generating a plurality of precharge signals Spre1 to Spre4 is illustrated.
The electro-optical device according to this embodiment has a configuration in which these modes are combined. In the electro-optical device according to this embodiment, the same elements as those in the first embodiment or the second embodiment are denoted by the same reference numerals, and the description thereof is omitted as appropriate.

FIG. 8 is a block diagram illustrating a configuration of the electro-optical device according to the present embodiment. As shown in the figure, the control circuit 30 of the electro-optical device D3 includes a precharge signal Spre1 that becomes a precharge potential corresponding to the blocks B1 and B3 and a precharge potential that corresponds to the blocks B2 and B4. The charge signal Spre2 is generated and output to the precharge signal line 61 in parallel. For example, as shown in FIG. 5, it is assumed that a data system image is displayed in each of the blocks B1 and B4 and a natural image system image is displayed in each of the blocks B2 and B3. In this case, as shown in FIG. 9, the precharge signal Spre1 is precharged corresponding to the image of the block B1 in the block period Tb1, which is the first half of the selection period (here, the selection period in which the data potential X is positive). It becomes the potential VH2, and in the block period Tb2 immediately after that, it becomes the precharge potential VH1 corresponding to the image of the block B3. Similarly, the precharge signal Spre2 becomes the precharge potential VH1 corresponding to the block B2 in the block period Tb1, and becomes the precharge potential VH2 corresponding to the block B4 in the block period Tb2. As shown in FIG. 8, blocks B1 and B3 in the precharge circuit 50 are shown.
Are connected in common to the precharge signal line 61 to which the precharge signal Spre1 is supplied, and the source electrodes of the sampling switches 511 corresponding to the blocks B2 and B4 are precharge signals. Commonly connected to the precharge signal line 61 to which Spre2 is supplied.

On the other hand, the sampling signal P1 is supplied from the unit circuit 521 to the gate electrodes of the sampling switches 511 corresponding to the blocks B1 and B2 in the precharge circuit 50, and the gate electrodes of the sampling switches 511 corresponding to the blocks B3 and B4 are supplied to the gate electrodes. The sampling signal P2 is supplied from the unit circuit 521. As shown in FIG. 9, the sampling signal P1 becomes active level during the precharge period Tp of the block period Tb1, and the sampling signal P2 is half of the precharge clock PCK and the inverted precharge clock / PCK from the start point of the block period Tb1. At the timing delayed by the length of time corresponding to the period (
That is, it becomes an active level (in the precharge period Tp of the block period Tb2). In the data output period Td of the block period Tb1, the data potential X is sequentially applied to the data lines 14 belonging to the blocks B1 and B2. In the data output period Td of the block period Tb2, the data potential X belongs to the blocks B3 and B4. A data potential X is applied to each data line 14 in order.

With the above configuration, in the precharge period Tp of the block period Tb1, the block B
The sampling switches 511 corresponding to 1 and B2 are simultaneously turned on by the sampling signal P1, and the precharge potentials of the precharge signals Spre1 and Spre2 at that time are supplied to the blocks B1 and B2 via these sampling switches 511. Data line 1
4 respectively. More specifically, in this precharge period Tp, the precharge potential VH2 of the precharge signal Spre1 is applied to all the data lines 14 in the block B1, and all the data lines 14 in the block B2 are applied. Precharge signal Spre2
The precharge potential VH1 is applied. By repeating the same operation in the precharge period Tp of the block period Tb2, the precharge potential VH1 of the precharge signal Spre1 is applied to each data line 14 of the block B3, and to each data line 14 of the block B4. A precharge potential VH2 of the precharge signal Spre2 is applied. Similar to the first embodiment, the potentials of the precharge signals Spre1 and Spre2 are determined according to the polarity of the data potential X, and the application of the data potential X to the data line 14 is stopped in each precharge period Tp. is there.

In this embodiment, the same effects as those of the first and second embodiments can be obtained. In the present embodiment, the data lines 14 of the group including the blocks B1 and B2 are precharged in a common precharge period Tp, and the data lines 14 of the group including the blocks B3 and B4 are shared. A configuration in which precharging is performed in the period Tp is illustrated. In this way, the group consisting of a plurality of blocks that are simultaneously precharged in a common precharge period is referred to as “
Corresponds to “block group”.

<D: Modification>
Various modifications are added to each embodiment. An example of a specific modification is as follows. In addition, you may combine each following aspect suitably.

(1) In each embodiment, the case where the 4n data lines 14 are divided into four blocks is illustrated, but the total number of blocks B and the number of data lines 14 belonging to each block B are arbitrary. Therefore, the total number of block periods Tb included in one selection period in the first embodiment, the total number of precharge signals Spre generated by the control circuit 30 in the second embodiment,
Furthermore, the total number of block groups and the total number of blocks B belonging to each block group in the third embodiment are arbitrarily changed. Further, the number of data lines 14 belonging to each block B may be different from each other. Further, in each embodiment, it is assumed that n data lines 14 adjacent to each other are a block B. However, a configuration in which data lines belonging to one block B are distributed in the column direction is also employed. The

(2) In each embodiment, the configuration in which each data line 14 is precharged by the precharge circuit 50 arranged separately from the data line drive circuit 40 is illustrated. However, the data line drive circuit 40 uses the image signal Vid as the image signal Vid. Based on this, it may be configured to execute precharge (so-called video precharge) of each data line 14. FIG. 10 is a block diagram illustrating a configuration of an electro-optical device according to this modification. As shown in the figure, the electro-optical device D4 does not include the precharge circuit 50 shown in the first to third embodiments. Instead, the data line driving circuit 40 has a total of 4n OR circuits 44 each corresponding to the sampling switch 411. The output terminal of each OR circuit 44 is connected to the gate electrode of the sampling switch 411 corresponding thereto. On the other hand, the control circuit 30 has four precharge pulses PG1 to PG.
G4 is output in parallel. These precharge pulses PG1 to PG4 have a selection period of 4
This signal is an active level in turn for each precharge period Tp located at the beginning of the equally divided block periods Tb1 to Tb4 (thus, these waveforms are similar to the sampling signals P1 to P4 shown in FIG. 4). N OR circuits 44 corresponding to each block Bk
Is connected in common to a signal line 67 to which a precharge pulse PGk corresponding to the block Bk is supplied. The other input terminal of each OR circuit 44 is connected to the output terminal of the corresponding unit circuit 421.

On the other hand, the image signal Vid output from the control circuit 30 is common to each embodiment in that it is at the data potential X in the data output period Td, but the precharge potential of the block Bk in the precharge period Tp of each block period Tbk. This is different from the image signal Vid of each embodiment. For example, the image signal Vid is a precharge potential (for example, data potential X) to be applied to each data line 14 of the block B1 in the precharge period Tp of the block period Tb1 (that is, the period in which the precharge pulse PG1 is at the active level). When the image of FIG. 5 is displayed in the selection period in which is positive, the precharge potential VH2). Under this configuration,
When the precharge pulse PGk becomes an active level in the precharge period Tp of each block period Tbk and the n sampling switches 411 corresponding to the block Bk are turned on at the same time, the potential of the image signal Vid at that time (that is, (Precharge potential) is applied to all the data lines 14 belonging to the block Bk. Even with this configuration,
The same effect as each embodiment is produced. Here, the electro-optical device D according to the first embodiment
Although the mode in which 1 is modified is illustrated, the electro-optical device D2 of the second embodiment is similarly modified to the electro-optical device D3 of the third embodiment.

(3) The configuration of the pixel P is not limited to that shown in FIG. For example, instead of a TFT element as a three-terminal switching element, a TFD (Thin Film Diode) as a two-terminal switching element
May be adopted as the switching element of each pixel P.

(4) In the second embodiment, the configuration in which the precharge potential is applied to each data line 14 in the period in which the scanning line 12 is selected and the switching element 73 is turned on is exemplified.
A configuration in which a precharge potential is applied to each data line 14 in a gap period of each selection period (that is, a horizontal blanking period in which the scanning signal Yi maintains an inactive level) may be employed. In this case, since the switching element 73 is turned off when the precharge potential is applied, the precharge potential is not written in the pixel capacitor 71. Therefore, there is an advantage that flickering of the screen can be effectively suppressed.

(5) In each embodiment, the configuration in which the voltage output circuit 31, the frame memory 33, and the determination circuit 35 are included in the control circuit 30 is illustrated, but these circuits are separate circuits from the control circuit 30. A configuration and a configuration integrated with other circuits (for example, the scanning line driving circuit 20, the data line driving circuit 40, and the precharge circuit 50) are also employed.

(6) In each embodiment, the configuration in which the characteristics of the image are determined by the arithmetic processing on the image data D is exemplified, but the method for determining the characteristics of the image is arbitrary. For example, when the user operates the input device (not shown) to input the characteristics of each block Bk (for example, whether the image is a natural image or a data image), the determination circuit is based on this input. 35
A configuration in which the image characteristics are determined is also employed.

(7) In the above, the electro-optical devices D1 to D4 using the liquid crystal 712 as the electro-optical material have been exemplified. However, the present invention is also applicable to devices using an electro-optical material other than the liquid crystal. For example, a display device using an OLED (Organic Light Emitting Diode) element such as an organic EL or a light-emitting polymer as an electro-optical material, or a microcapsule containing a colored liquid and white particles dispersed in the liquid is electro-optical. An electrophoretic display device used as a material, a twist ball display using a twist ball painted differently for each region of different polarity as an electro-optical material, a toner display using black toner as an electro-optical material,
Alternatively, the present invention is applied to various electro-optical devices such as a plasma display panel using a high-pressure gas such as helium or neon as an electro-optical material as in the embodiments.

<E: Electronic equipment>
Next, as an example of the electronic apparatus according to the invention, the configuration of a projection display device (projector) that uses the electro-optical devices D1 to D4 as light valves will be described. FIG. 11 is a plan view showing the configuration of the projection display device. As shown in this figure, the projection display device 2100
Is provided with a lamp unit 2102 made of a white light source such as a halogen lamp. The projection light emitted from the lamp unit 2102 is R (red), G (green), and two dichroic mirrors 2108 disposed inside.
The three primary colors B (blue) are separated and guided to the light valves 100R, 100G, and 100B corresponding to the primary colors, respectively. Note that B light has a longer optical path than other R and G colors, and therefore, in order to prevent the loss, B light passes through a relay lens system 2121 including an incident lens 2122, a relay lens 2123, and an exit lens 2124. Led.

Here, the configuration of the light valves 100R, 100G and 100B is the same as that of the electro-optical device D1.
Thru | or D4, it is the structure similar to either, and R, G, supplied from a processing circuit (illustration omitted)
It is driven by image data D corresponding to each color of B. The lights modulated by the light valves 100R, 100G, and 100B are incident on the dichroic prism 2112 from three directions. In the dichroic prism 2112, the R and B light beams are refracted at 90 degrees, while the G light beam travels straight. Therefore, after the images of the respective colors are combined, a color image is projected onto the screen 2120 by the projection lens 2114.

The light valves 100R, 100G, and 100B include a dichroic mirror 2
Since light corresponding to the primary colors of R, G, and B is incident by 108, there is no need to provide a color filter. In addition, the transmission images of the light valves 100R and 100B are projected after being reflected by the dichroic prism 2112, whereas the transmission image of the light valve 100G is projected as it is, so the horizontal scanning direction by the light valves 100R and 100B is The left-right reversed image is displayed in the direction opposite to the horizontal scanning direction by the light valve 100G.

In addition to the projection display device shown in FIG. 11, the electronic apparatus in which the electro-optical device according to the invention can be used includes a mobile phone, a portable personal computer, a digital video camera, a liquid crystal television, a viewfinder. Type (or monitor direct view) video recorder,
Car navigation devices, pagers, electronic notebooks, calculators, word processors, workstations, videophones, POS terminals, devices equipped with touch panels, and the like.

1 is a block diagram illustrating a configuration of an electro-optical device according to a first embodiment of the invention. FIG. It is a circuit diagram which shows the structure of each pixel. It is a figure which shows the relationship between a data potential and each precharge potential. 6 is a timing chart illustrating an operation of the electro-optical device according to the first embodiment. It is a figure which illustrates the relationship between the image displayed on a display area, and each block. FIG. 6 is a block diagram illustrating a configuration of an electro-optical device according to a second embodiment of the invention. 12 is a timing chart illustrating an operation of the electro-optical device according to the second embodiment. FIG. 10 is a block diagram illustrating a configuration of an electro-optical device according to a third embodiment of the invention. 12 is a timing chart illustrating an operation of the electro-optical device according to the third embodiment. FIG. 10 is a block diagram illustrating a configuration of an electro-optical device according to a modification. It is a figure which shows the structure of the projection type display apparatus which is an example of the electronic device which concerns on this invention.

Explanation of symbols

D1, D2, D3, D4: electro-optical device, Ad: display area, P: pixel, 12: scanning line, 14: data line, 20: scanning line drive circuit, 30: control circuit, 31 ... Voltage output circuit, 33 ... Frame memory, 35 ... Determination circuit, 40 ... Data line drive circuit, 50 ...
Precharge circuit, 411, 511... Sampling switch, Bk (B1, B2, B3, B
4)... Block, Tbk (Tb1, Tb2, Tb3, Tb4)... Block period, Tp... Precharge period, Td.

Claims (12)

A drive circuit for an electro-optical device having a display area in which pixels are arranged corresponding to each intersection of a plurality of scanning lines and a plurality of data lines,
A scanning line driving circuit for sequentially selecting each of the plurality of scanning lines for each selection period;
In a data output period included in one selection period, for each of the plurality of data lines, data corresponding to the gradation of the pixel corresponding to the intersection of the data line and the scanning line selected by the scanning line driving circuit A data line driving circuit for supplying a potential;
A determination circuit that divides the display area into a plurality of blocks and determines whether the image displayed in the block is an image in which the same gradation is continuous over a wide range of pixels, for each block;
A drive circuit for an electro-optical device, comprising: a precharge voltage output circuit that outputs a precharge potential corresponding to each of the plurality of blocks to a data line belonging to the block based on the determination result. The determination circuit determines a difference in gradation between adjacent pixels. If the same gradation continues over a wide range of pixels, the determination circuit determines that the image is a data image, and in the other case, the image is a natural image image. The drive circuit of the electro-optical device according to claim 1, wherein the determination is performed. A drive circuit for an electro-optical device having a display area in which pixels are arranged corresponding to each intersection of a plurality of scanning lines and a plurality of data lines,
A scanning line driving circuit for sequentially selecting each of the plurality of scanning lines for each selection period;
In a data output period included in one selection period, for each of the plurality of data lines, data corresponding to the gradation of the pixel corresponding to the intersection of the data line and the scanning line selected by the scanning line driving circuit A data line driving circuit for supplying a potential;
A determination circuit that divides the display area into a plurality of blocks and determines whether or not an image displayed in the block is a moving image, for each block;
A drive circuit for an electro-optical device, comprising: a precharge voltage output circuit that outputs a precharge potential corresponding to each of the plurality of blocks to a data line belonging to the block based on the determination result. The drive circuit of the electro-optical device according to claim 3, wherein the determination circuit determines a change with time in gradation of a pixel. The precharge voltage output circuit includes:
In the precharge period immediately preceding the data output period, to the data line belonging to the block, the electro-optic according to any one of claims 1 or et請 Motomeko 3, characterized in that for supplying the precharge potential Device drive circuit. The precharge voltage output circuit includes:
6. The electro-optical device according to claim 5, wherein, in the precharge period, the plurality of blocks are sequentially selected, and a precharge potential corresponding to the block is output to a data line belonging to the selected block. Driving circuit. The precharge voltage output circuit includes:
6. The electro-optic according to claim 5, wherein, in the precharge period, all data lines belonging to the plurality of blocks are selected and a precharge potential corresponding to the block is output for each of the plurality of blocks. Device drive circuit. An electro-optical device including a display area in which pixels are arranged corresponding to each intersection of a plurality of scanning lines and a plurality of data lines,
A scanning line driving circuit for sequentially selecting each of the plurality of scanning lines for each selection period;
In a data output period included in one selection period, for each of the plurality of data lines, data corresponding to the gradation of the pixel corresponding to the intersection of the data line and the scanning line selected by the scanning line driving circuit A data line driving circuit for supplying a potential;
A determination circuit that divides the display area into a plurality of blocks and determines whether the image displayed in the block is an image in which the same gradation is continuous over a wide range of pixels, for each block;
An electro-optical device comprising: a precharge voltage output circuit that outputs a precharge potential corresponding to each of the plurality of blocks to a data line belonging to the block based on the determination result. An electro-optical device including a display area in which pixels are arranged corresponding to each intersection of a plurality of scanning lines and a plurality of data lines,
A scanning line driving circuit for sequentially selecting each of the plurality of scanning lines for each selection period;
In a data output period included in one selection period, for each of the plurality of data lines, data corresponding to the gradation of the pixel corresponding to the intersection of the data line and the scanning line selected by the scanning line driving circuit A data line driving circuit for supplying a potential;
A determination circuit that divides the display area into a plurality of blocks and determines whether or not an image displayed in the block is a moving image, for each block;
An electro-optical device comprising: a precharge voltage output circuit that outputs a precharge potential corresponding to each of the plurality of blocks to a data line belonging to the block based on the determination result.   An electronic apparatus comprising the electro-optical device according to claim 8. A driving method of an electro-optical device including a display area in which pixels are arranged corresponding to each intersection of a plurality of scanning lines and a plurality of data lines,
Sequentially selecting each of the plurality of scan lines for each selection period;
In a data output period included in one selection period, for each of the plurality of data lines, data corresponding to the gradation of the pixel corresponding to the intersection of the data line and the scanning line selected by the scanning line driving circuit Supplying a potential;
Dividing the display area into a plurality of blocks, and determining for each block whether or not the image displayed in the block is an image in which the same gradation is continuous over a wide range of pixels;
And a step of outputting a precharge potential corresponding to each of the plurality of blocks to a data line belonging to the block based on the determination result. A driving method of an electro-optical device including a display area in which pixels are arranged corresponding to each intersection of a plurality of scanning lines and a plurality of data lines,
Sequentially selecting each of the plurality of scan lines for each selection period;
In a data output period included in one selection period, for each of the plurality of data lines, data corresponding to the gradation of the pixel corresponding to the intersection of the data line and the scanning line selected by the scanning line driving circuit Supplying a potential;
Dividing the display area into a plurality of blocks, and determining for each block whether or not an image displayed in the block is a moving image;
And outputting a precharge potential corresponding to each of the plurality of blocks to a data line belonging to the block based on the determination result.

Images