JP2019207398A - Electro-optical device, drive method for electro-optical device, and electronic apparatus - Google Patents

Abstract

To improve the display quality of an electro-optical device.SOLUTION: The electro-optical device comprises: a plurality of scan lines; k signal lines (k is an integer of 3 or greater); a reference line given a reference potential; a pixel arranged in correspondence to each intersection of the plurality of scan lines and the k signal lines, including a holding capacitor connected to the reference lines, and holding the potential corresponding to an image signal in the holding capacitor; an image signal circuit for sequentially supplying the image signal to the k signal lines in k supply periods based on k selection signals for sequentially selecting the k signal lines during a horizontal scan period; a precharge circuit for supplying a precharge signal to a signal line among the k signal lines before being supplied with the image signal by the image signal circuit in a prescribed order during a horizontal scan period; and a control circuit for controlling the k selection signals so that at lease one of first and last supply periods among the k supply periods is extended to be longer than a prescribed supply period except the first and last supply periods among the k supply periods.SELECTED DRAWING: Figure 2

Description

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

  An electro-optical device that displays an image using a liquid crystal element supplies a video voltage based on an image signal designating the gradation of each pixel to each pixel via a data line, thereby transmitting the liquid crystal included in each pixel. The rate is controlled to the transmission based on the video voltage. As a result, the gradation of each pixel is set to the gradation specified by the image signal. In general, each pixel has a storage capacitor connected in parallel with the liquid crystal element. One end of the storage capacitor is connected to the pixel electrode of the liquid crystal element, and the other end is connected to the common electrode of the liquid crystal element via a capacitor line.

  When the supply of video voltage to each pixel is insufficient, such as when sufficient time to supply the video voltage to each pixel cannot be secured, each pixel can accurately display the gradation specified by the image signal. There are cases where it is not possible. For this reason, in the conventional electro-optical device, for example, by performing precharge that precharges the data lines to a predetermined voltage level, measures against insufficient writing of the video voltage to each pixel are taken. For example, in Patent Document 1, a large number of data lines are divided into X blocks including a predetermined number of data lines, and an image signal is applied to the data lines included in the nth block and at the same time included in the n + 1th block. There has been proposed a liquid crystal display device that applies a precharge voltage to a data line.

JP 2000-89194 A

  However, when a video voltage or a precharge voltage is supplied to the data line, a change in the voltage level of the data line is propagated to the capacitor line via the coupling capacitance between the data line and the capacitor line, and noise is generated in the capacitor line. The conventional electro-optical device has a problem in that display unevenness occurs due to the influence of noise generated in the capacitance line.

  In order to solve the above problems, one embodiment of the electro-optical device according to the present invention includes a plurality of scanning lines, k signal lines (k is an integer of 3 or more), a reference line to which a reference potential is applied, and the plurality A pixel that is arranged corresponding to each intersection of the scanning lines and the k signal lines, includes a storage capacitor connected to the reference line, and holds a potential corresponding to an image signal in the storage capacitor; An image signal circuit for sequentially supplying image signals to the k signal lines in the k supply periods based on k selection signals for sequentially selecting the k signal lines in a scanning period; In a scanning period, a precharge circuit that supplies a precharge signal in a predetermined order to a signal line before the image signal circuit supplies an image signal among the k signal lines, and in the horizontal scanning period, the Image signal in order for each of k signal lines At least one of the first supply period and the last supply period of the k supply periods to be supplied is a predetermined supply excluding the first supply period and the last supply period of the k supply periods. And a control circuit for controlling the k selection signals so as to be longer than the period.

  In addition, according to one aspect of the driving method of the electro-optical device according to the invention, a plurality of scanning lines, k signal lines (k is an integer of 3 or more), a reference line to which a reference potential is applied, A pixel that is arranged corresponding to each intersection of a scanning line and the k signal lines, includes a storage capacitor connected to the reference line, and holds a potential corresponding to an image signal in the storage capacitor; and horizontal scanning An image signal circuit for sequentially supplying image signals to the k signal lines in the k supply periods based on k selection signals for sequentially selecting the k signal lines in the period; and the horizontal scanning. A driving method of an electro-optical device, comprising: a precharge circuit that supplies a precharge signal in a predetermined order to a signal line before the image signal circuit supplies an image signal among the k signal lines in the period And in the horizontal scanning period, At least one of the first supply period and the last supply period among the k supply periods for sequentially supplying the image signals to each of the signal lines is defined as the first supply period among the k supply periods. The k selection signals are controlled to be longer than a predetermined supply period excluding the period and the last supply period.

1 is an explanatory diagram of an electro-optical device according to a first embodiment of the invention. FIG. 1 is a block diagram illustrating a configuration of an electro-optical device according to a first embodiment. It is a circuit diagram which shows the structure of a pixel. It is a figure which shows the relationship between the motion of the potential of a signal line, and the motion of the potential of a capacity line. It is a figure which shows the operation timing of a 1st horizontal scanning period. It is a figure which shows the operation timing of the 2nd horizontal scanning period. It is a figure which shows the operation timing of the 3rd horizontal scanning period. It is a figure which shows the operation timing of a 4th horizontal scanning period. It is a figure which shows the operation timing of the 5th horizontal scanning period. It is a figure which shows the operation timing of the 6th horizontal scanning period. It is a figure which shows the operation timing of the 7th horizontal scanning period. It is a figure which shows the operation timing of the 8th horizontal scanning period. 6 is a flowchart illustrating an example of an operation of the electro-optical device according to the first embodiment. It is a figure which shows the operation | movement timing of the 1st horizontal scanning period in 2nd Embodiment of this invention. It is a figure which shows the operation | movement timing of the 1st horizontal scanning period in the modification 1 of 1st Embodiment. It is a figure which shows the operation | movement timing of the 2nd horizontal scanning period in the modification 1. It is explanatory drawing which shows an example of an electronic device. It is explanatory drawing which shows the other example of an electronic device. It is explanatory drawing which shows the other example of an electronic device.

<First Embodiment>
A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an explanatory diagram of an electro-optical device 1 according to the first embodiment of the invention. FIG. 1 shows the configuration of a signal transmission system for the electro-optical device 1. The electro-optical device 1 includes an electro-optical panel 100, a driving integrated circuit 200 such as a driver IC (Integrated Circuit), and a flexible circuit board 300. The electro-optical panel 100 is connected to a flexible circuit board 300 on which the driving integrated circuit 200 is mounted. The electro-optical panel 100 is connected to a host CPU (Central Processing Unit) device (not shown) via the flexible circuit board 300 and the driving integrated circuit 200. The driving integrated circuit 200 is an apparatus that receives an image signal and various control signals for driving control from the host CPU device via the flexible circuit board 300 and drives the electro-optical panel 100 via the flexible circuit board 300. is there.

  The electro-optical device 1 displays an image using a liquid crystal element. For example, the electro-optical device 1 supplies a video voltage based on an image signal designating the gradation of each pixel to each pixel via a signal line, whereby the transmittance of the liquid crystal included in each pixel is based on the video voltage. Control to transmittance. As a result, the gradation of each pixel is set to the gradation specified by the image signal. The electro-optical device 1 employs polarity inversion driving that inverts the polarity of the voltage applied to the liquid crystal element at regular intervals in order to prevent electrical deterioration of the electro-optical material. For example, the electro-optical device 1 inverts the level of the image signal supplied to the pixel via the signal line every vertical scanning period with respect to the center voltage of the image signal. Note that the period for reversing the polarity can be set arbitrarily, and may be, for example, a natural number times the vertical scanning period. In this specification, the case where the voltage of the image signal is higher than the predetermined voltage such as the center voltage is positive, and the case where the voltage of the image signal is lower than the predetermined voltage is negative. .

  FIG. 2 is a block diagram illustrating a configuration of the electro-optical device 1 according to the first embodiment. The electro-optical device 1 includes a plurality of scanning lines 120, a plurality of signal lines 122, a capacitor line 124 to which a reference potential is applied, a plurality of pixels PX, an image signal circuit 140, a precharge circuit 160, a scanning line. A driving circuit 180 and a control circuit 280 are included. For example, among the blocks shown in FIG. 2, the control circuit 280, a signal line drive circuit 240 and a precharge voltage control circuit 260 described later are included in the drive integrated circuit 200. 2, blocks excluding the control circuit 280, the signal line driver circuit 240, and the precharge voltage control circuit 260 are included in the electro-optical panel 100. The capacitor line 124 is an example of a reference line.

  The plurality of signal lines 122 are classified into, for example, a signal line group including k signal lines 122. However, k is an integer of 3 or more. In the example shown in FIG. 2, k is 8, and the total number of signal lines 122 is 4160. Therefore, 4160 signal lines 122 are classified into 520 signal line groups including 8 signal lines 122. In addition, if k is an integer greater than or equal to 3, it will not be limited to 8. Further, the total number of signal lines 122 is not limited to the example shown in FIG. For example, the total number of signal lines 122 may be k. In this case, the number of signal line groups is one.

  Each of the plurality of pixels PX is arranged corresponding to each intersection of the plurality of scanning lines 120 and the plurality of signal lines 122. In the example shown in FIG. 2, the pixels PX are arranged in a matrix of 2160 rows × 4160 columns. The number of pixels PX is not limited to the example shown in FIG. Each pixel PX has a storage capacitor Cst connected to the capacitor line 124 as shown in FIG. In FIG. 2, the row of the pixel PX described at the top of the drawing is the first row, and the column of the pixel PX described at the leftmost of the drawing is the first column. Hereinafter, the scanning line 120 connected to the pixel PX in the m-th row is also referred to as the scanning line 120 in the m-th row, and the signal line 122 connected to the pixel PX in the n-th column is referred to as the n-th column. Also referred to as signal line 122. In the example shown in FIG. 2, m is an integer from 1 to 2160, and n is an integer from 1 to 4160.

  The scanning signal G is supplied to the scanning line 120, and the image signal S or the precharge signal PRC is supplied to the signal line 122. The number at the end of the code of the scanning signal G corresponds to the row number. Further, the numbers at the end of the signs of the image signal S, the write switch SWv and the precharge switch SWp described later correspond to the column numbers. A common voltage Vcom is supplied to the capacitor line 124. The potential of the capacitor line 124 given by the common voltage Vcom, that is, the potential based on the common voltage Vcom is an example of a reference potential.

  The image signal circuit 140 sequentially supplies the image signal S to each of the eight signal lines 122 included in each signal line group, that is, each of the k signal lines 122 in the horizontal scanning period. The horizontal scanning period is a period for writing the video voltage based on the image signal S supplied to the signal line 122 of each column to the pixels PX in one row. The row to be written is selected by the scanning signal G supplied from the scanning line driving circuit 180 to the scanning line 120.

  The image signal circuit 140 includes a plurality of write selection circuits SUv provided corresponding to a plurality of signal line groups, and a signal line drive circuit 240 that outputs the image signal S to each write selection circuit SUv. For example, the write selection circuit SUv1 corresponds to a signal line group including eight signal lines 122 from the first column to the eighth column, and the signal lines 122 to be supplied with the image signal S are arranged from the first column to the eighth column. Up to eight signal lines 122 are selected. The write selection circuit SUv520 corresponds to the signal line group including the eight signal lines 122 from the 4153rd column to the 4160th column, and the signal line 122 to be supplied with the image signal S is changed from the 4153th column to the 4160th column. Up to eight signal lines 122 are selected. The image signal S is supplied to the signal line 122 selected by the write selection circuit SUv.

  Each write selection circuit SUv has eight signal lines 122 included in the corresponding signal line group, that is, k write switches SWv respectively connected to the k signal lines 122. The write switch SWv is an N-channel transistor configured by, for example, a TFT (thin film transistor) or the like, and switches between a conductive state and a non-conductive state according to the level of a write selection signal SEL received at a control terminal such as a gate. Is set to one of the following. Note that the write switch SWv may be a P-channel transistor or a switching element other than a TFT. The configuration of each write selection circuit SUv is the same except that the connection destination of terminals other than the control terminal of the write switch SWv is different for each write selection circuit SUv. For this reason, the following description focuses on the configuration of the write selection circuit SUv1.

  For example, the write selection circuit SUv1 has eight write switches SWv1-SWv8. One end of each of the write switches SWv1 to SWv8 is connected to each of the eight signal lines 122 from the first column to the eighth column. The other ends of the write switches SWv 1 to SWv 8 are connected to each other and receive the image signals S 1 to S 8 in order from the signal line driver circuit 240. Then, in accordance with control from the control circuit 280 described later, among the write switches SWv1 to SWv8, the write switch SWv set to the conductive state is sequentially switched in one horizontal scanning period. As a result, the image signals S <b> 1 to S <b> 8 output in order from the signal line driver circuit 240 are sequentially supplied to the corresponding signal lines 122.

  For example, when the write selection signal SEL1 is set to a selection potential such as a high level, the write switch SWv1 that receives the write selection signal SEL1 transitions to a conductive state. As a result, the image signal S1 is supplied from the signal line driver circuit 240 to the signal line 122 in the first column, and the signal line 122 in the first column is charged to a video voltage based on the image signal S1. Note that the write selection signal SEL1 is also output to the write switch SWv of the same series as the write switch SWv1, for example, the write switch SWv4153 in each write selection circuit SUv other than the write selection circuit SUv1.

  In the example shown in FIG. 2, the write switches SWv having the same value after dividing the last digit of the sign of the write switch SWv by 8 are the same series of write switches SWv, and the common write selection signal SEL is controlled by the control terminal. Receive at. For example, the write switch SWv1 is the same series as the write switch SWv4153, and the write switch SWv8 is the same series as the write switch SWv4160.

  Hereinafter, the write switch SWv controlled by the write selection signal SELi is also referred to as an i-th series write switch SWv. Note that i is an integer of 1 to 8, that is, an integer of 1 to k. The signal line 122 connected to the i-th series write switch SWv is also referred to as an i-th series signal line 122. Therefore, the number at the end of the code of the write selection signal SEL corresponds to the sequence number of the signal line 122 to be controlled. Similarly, the number at the end of the sign of the precharge selection signal PSEL described later also corresponds to the sequence number of the signal line 122 to be controlled.

  The signal line drive circuit 240 outputs the image signal S for 8 pixels, that is, the image signal S for k pixels, to each write selection circuit SUv as a time-series serial signal. For example, the signal line driver circuit 240 sequentially outputs the image signals S1 to S8 to the write selection circuit SUv1 and outputs the image signals S4153 to S4160 to the write selection circuit SUv520 in order. The image signals S supplied to the signal lines 122 of the same series are output in parallel from the signal line driving circuit 240 to the write selection circuits SUv. That is, the signal line driving circuit 240 outputs each image signal S supplied to the signal line 122 of the same series in parallel to each of the plurality of signal line groups.

  The precharge circuit 160 supplies a precharge signal PRC to the signal line 122 before the image signal circuit 140 supplies the image signal S among the k signal lines 122 included in each signal line group in the horizontal scanning period. Supply in order. As a result, the signal line 122 before the image signal S is supplied is charged to a predetermined precharge voltage based on the precharge signal PRC. That is, the precharge circuit 160 performs precharge that charges the signal line 122 before the image signal S is supplied to a predetermined precharge voltage. The predetermined order is a predetermined precharge execution order, which may be the same order as the arrangement order of the signal lines 122 or may be a different order.

  For example, the precharge circuit 160 includes a plurality of precharge selection circuits SUp provided corresponding to a plurality of signal line groups, a precharge voltage control circuit 260 that outputs a precharge signal PRC to each precharge selection circuit SUp, and Have For example, the precharge selection circuit SUp1 corresponds to a signal line group including eight signal lines 122 from the first column to the eighth column, and the signal lines 122 to be supplied with the precharge signal PRC are provided from the first column to the eighth column. Select from eight signal lines 122 up to the column. The precharge selection circuit SUp520 corresponds to the signal line group including the eight signal lines 122 from the 4153rd column to the 4160th column, and the signal line 122 to which the precharge signal PRC is supplied from the 4153th column to the 4160th column. Select from eight signal lines 122 up to the column. A precharge signal PRC is supplied to the signal line 122 selected by the precharge selection circuit SUp.

  Each precharge selection circuit SUp has eight signal lines 122 included in the corresponding signal line group, that is, k precharge switches SWp connected to the k signal lines 122, respectively. The precharge switch SWp is, for example, an N-channel transistor composed of a TFT or the like, and is either in a conductive state or a non-conductive state depending on the level of the precharge selection signal PSEL received at a control terminal such as a gate. Set to Note that the precharge switch SWp may be a P-channel transistor or a switching element other than a TFT. The configurations of the respective precharge selection circuits SUp are the same as each other except that the signal line 122 connected to the precharge switch SWp is different for each precharge selection circuit SUp. For this reason, the following description focuses on the configuration of the precharge selection circuit SUp1.

  For example, the precharge selection circuit SUp1 has eight precharge switches SWp1-SWv8. One end of each of the precharge switches SWp1 to SWp8 is connected to each of the eight signal lines 122 from the first column to the eighth column. The other ends of the precharge switches SWp 1 to SWp 8 are connected to each other and receive a precharge signal PRC from the precharge voltage control circuit 260. Then, the precharge switch SWp set to the conductive state is selected from the precharge switches SWp1 to SWp8 in accordance with control from the control circuit 280 described later. As a result, the precharge signal PRC output from the precharge voltage control circuit 260 is supplied to the signal line 122 connected to the conductive precharge switch SWp.

  For example, when the precharge selection signal PSEL1 is set to a selection potential such as a high level, the first series of precharge switches SWp such as the precharge switch SWp1 that receives the precharge selection signal PSEL1 transition to a conductive state. As a result, the precharge signal PRC is supplied from the precharge voltage control circuit 260 to the first series of signal lines 122, and the first series of signal lines 122 is charged to the precharge voltage based on the precharge signal PRC. The period in which the precharge selection signal PSEL is maintained at the selection potential is an example of a precharge period in which the precharge signal PRC is supplied to the signal line 122.

  The other end of each of the precharge switches SWp1 to SWp8 is also connected to the other end of the precharge switch SWp of the precharge selection circuit SUp other than the precharge selection circuit SUp1. That is, the other ends of precharge switches SWp 1 -SWp 4160 are connected to each other and receive precharge signal PRC from precharge voltage control circuit 260.

  The precharge voltage control circuit 260 supplies a precharge voltage based on the polarity of the image signal S to the signal line 122 based on a set value stored in an external set value storage means or the like (not shown). PRC is output to a plurality of precharge switches SWp.

  The scanning line driving circuit 180 sequentially outputs a scanning signal G for selecting a row to be supplied with the image signal S to the plurality of pixels PX for each row. For example, the scanning line driving circuit 180 changes the potential of the scanning signal G1 to a selection potential such as a high level in the first horizontal scanning period in which the video voltage is written to the pixels PX in the first row.

  The control circuit 280 receives external signals such as a vertical synchronization signal defining a vertical scanning period and a horizontal synchronization signal defining a horizontal scanning period from an external host CPU device (not shown). Then, the control circuit 280 synchronously controls the scanning line driving circuit 180, the image signal circuit 140, and the precharge circuit 160 based on a signal received from the host CPU device.

  For example, the control circuit 280 controls the timing of supplying the image signal S to the eight signal lines 122 included in each signal line group, that is, the k signal lines 122, using the write selection signal SEL or the like. The control circuit 280 outputs write selection signals SEL1 to SEL8 for selecting the signal lines 122 to which the image signal S is supplied to the write switches SWv of each series. For example, when the image signal S is supplied to the first series of signal lines 122, the control circuit 280 changes the potential of the write selection signal SEL1 to the selection potential. As a result, the first series writing switch SWv is changed to the conductive state, and the image signal S output from the signal line driving circuit 240 is supplied to the first series signal line 122.

  Note that the control circuit 280 adjusts the length of the supply period of the image signal S to the signal lines 122 of each series by adjusting the period during which the write selection signal SEL is maintained at the selection potential. In other words, in the horizontal scanning period, the control circuit 280 supplies k signal periods 122 to the eight signal lines 122 included in each signal line group, that is, k signal lines 122 in order to supply the image signal S sequentially. Control the length of For example, the control circuit 280 determines one or more of the first supply period and the last supply period among the k supply periods, excluding the first supply period and the last supply period among the k supply periods. Longer than the predetermined supply period.

  Further, the control circuit 280 outputs precharge selection signals PSEL1 to PSEL8 for selecting the signal line 122 of the series to which the precharge signal PRC is supplied to the precharge switches SWp of each series. For example, when supplying the precharge signal PRC to the second series of signal lines 122, the control circuit 280 transitions the potential of the precharge selection signal PSEL2 to the selection potential. As a result, the second series write switch SWv transitions to the conductive state, and the precharge signal PRC output from the precharge voltage control circuit 260 is supplied to the second series signal line 122. The operation timing of the write selection signal SEL and the precharge selection signal PSEL will be described with reference to FIGS.

  FIG. 3 is a circuit diagram illustrating a configuration of the pixel PX. Each pixel PX includes a liquid crystal element 130, a storage capacitor Cst connected to the capacitor line 124, and a pixel transistor TRh. The liquid crystal element 130 is an electro-optical element that includes a pixel electrode 132 and a common electrode 134 facing each other, and a liquid crystal 136 disposed between the pixel electrode 132 and the common electrode 134. When the transmittance of the liquid crystal 136 changes according to the voltage applied between the pixel electrode 132 and the common electrode 134, the display gradation changes. The common electrode 134 is supplied with a common voltage Vcom, which is a constant voltage, through a common line (not shown).

  The storage capacitor Cst is provided in parallel with the liquid crystal element 130. One terminal of the storage capacitor Cst is connected to the pixel transistor TRh, and the other terminal is connected to the common electrode 134 via the capacitor line 124.

  The pixel transistor TRh is an N-channel transistor configured by, for example, a TFT, and is provided between the liquid crystal element 130 and the signal line 122. The pixel transistor TRh is set to either a conductive state or a non-conductive state according to the level of the scanning signal G supplied to the scanning line 120 connected to the gate. That is, the pixel transistor TRh controls electrical connection between the liquid crystal element 130 and the signal line 122. For example, when the scanning signal Gm is set to the selection potential, the pixel transistors TRh in the pixels PX in the m-th row are changed to the conductive state at the same time or almost simultaneously.

  When the pixel transistor TRh is controlled to be conductive, a video voltage based on the image signal S supplied from the signal line 122 is applied to the liquid crystal element 130. The liquid crystal 136 is set to a transmittance based on the image signal S when a video voltage based on the image signal S is applied. When a light source (not shown) is turned on, light emitted from the light source passes through the liquid crystal 136 of the liquid crystal element 130 included in the pixel PX and is output to the outside of the electro-optical device 1. That is, when the video voltage based on the image signal S is applied to the liquid crystal element 130 and the light source is turned on, the pixel PX displays a gradation based on the image signal S.

  In addition, the storage capacitor Cst provided in parallel with the liquid crystal element 130 is charged with a video voltage applied to the liquid crystal element 130. That is, each pixel PX holds the potential corresponding to the image signal S in the holding capacitor Cst.

  Note that when the pixel transistor TRh is controlled to be in a conductive state, the storage capacitor Cst and the signal line 122 are electrically connected. For this reason, the fluctuation of the potential E122 of the signal line 122 may be propagated to the capacitor line 124 via the storage capacitor Cst. Further, the fluctuation of the potential E122 of the signal line 122 propagates to the capacitor line 124 due to the coupling capacitance between the signal line 122 and the capacitor line 124 (not shown). Although FIG. 2 shows an example of the arrangement of capacitor lines in the row direction, this is particularly noticeable when the capacitor lines 124 are arranged so as to overlap the column direction, that is, the signal lines 122. In this case, a period in which the potential E124 of the capacitor line 124 is unstable occurs. Next, with reference to FIG. 4, the potential fluctuation of the capacitor line 124 accompanying the potential fluctuation of the signal line 122 will be described.

  FIG. 4 is a diagram illustrating the relationship between the movement of the potential E122 of the signal line 122 and the movement of the potential E124 of the capacitor line 124. FIG. 4 shows the relationship between the movement of the potential E122 of the signal line 122 and the movement of the potential E124 of the capacitor line 124 when raster display is executed by positive polarity driving. The potential E122 [i] indicates the potential E122 of the i-th series signal line 122, and the potential E122 [j] indicates the potential E122 of the j-th series signal line 122. In the example illustrated in FIG. 4, the image signal Si is supplied to the i-th series signal line 122, and the precharge signal PRC is supplied to the j-th series signal line 122. The video voltage Vvidp indicates a voltage based on the image signal Si during positive polarity driving, and the precharge voltage Vprcp indicates a voltage based on the precharge signal PRC during positive polarity driving. For example, the video voltage Vvidp is 12V, and the precharge voltage Vprcp is 4V.

  The potential E122 [i] of the i-th series signal line 122 to which the video voltage Vvidp is applied transitions from the precharge voltage Vprcp to the video voltage Vvidp when the image signal Si for applying the video voltage Vvidp is supplied. To do. In this case, the potential E124 of the capacitor line 124 rises from the common voltage Vcom and returns to the common voltage Vcom again.

  The potential E122 [j] of the j-th series signal line 122 to be precharged is supplied from the video voltage Vvidp to the precharge voltage Vprcp when the precharge signal PRC for applying the precharge voltage Vprcp is supplied. Transition to. In this case, the potential E124 of the capacitor line 124 decreases from the common voltage Vcom and returns to the common voltage Vcom again.

  When the precharge signal PRC is supplied, the potential E124 of the capacitor line 124 changes in the opposite or the same amount as the change of the potential E124 of the capacitor line 124 when the image signal Si is supplied. Therefore, by overlapping the precharge period, which is the supply period of the precharge signal PRC, with the supply period of the image signal S, the potential fluctuation of the capacitor line 124, that is, noise superimposed on the capacitor line 124 is canceled. In the following, the effect of canceling noise superimposed on the capacitor line 124 by applying potential fluctuations to the capacitor line 124 that have the same or similar fluctuation amounts and opposite directions of fluctuation is also referred to as a counter noise effect. When the counter noise effect is obtained, the potential fluctuation of the capacitor line 124 is suppressed and the potential E124 of the capacitor line 124 is stabilized early compared to the case where the counter noise effect is not obtained.

  In a natural image or the like, unlike the example shown in FIG. 4, the relationship between the potential fluctuation of the capacitance line 124 when the image signal Si is supplied and the potential fluctuation of the capacitance line 124 when the precharge signal PRC is supplied is different from the counter noise. The effect is not always obtained. However, in a natural image or the like, random elements are stronger than a solid image in which all pixels PX have the same pixel value. For this reason, even if the counter noise effect cannot be obtained in a natural image or the like, there is less visual discomfort than a solid image in which the counter noise effect cannot be obtained.

  FIGS. 5 to 12 show operation timings of the horizontal scanning periods H of the electro-optical device 1 when raster display is executed by positive polarity driving. The number in the brackets of the sign of the potential E122 indicates the series of the signal line 122. For example, the potential E122 [1] indicates the potential E122 of the first series of signal lines 122, and the potential E122 [8] indicates the potential E122 of the eighth series of signal lines 122. In the example shown in FIGS. 5 to 12, the image signal circuit 140 outputs the image signal to one signal line 122 among the k signal lines 122 in each of the k supply periods included in the horizontal scanning period H. S is supplied. In addition, the precharge circuit 160 includes k pieces of precharge periods corresponding to the first to (k−1) th supply periods among the k supply periods included in the horizontal scanning period H. A precharge signal PRC is supplied to one of the signal lines 122. The control circuit 280 uses the first supply period and the kth supply period among the k supply periods included in the horizontal scanning period H as the first supply among the k supply periods. It is made longer than other supply periods excluding the period and the k-th supply period.

  FIG. 5 is a diagram showing the operation timing in the first horizontal scanning period H1. The first horizontal scanning period H1 is a horizontal scanning period H for writing the video voltage Vvidp to the pixels PX in the first row. In the first horizontal scanning period H1, the potential of the scanning signal G1 supplied to the scanning line 120 in the first row is set to a high level. The scanning signals G2-G2160 supplied to the scanning lines 120 other than the first row are maintained at a low level.

  The high level periods of the write selection signals SEL1 to SEL8 are switched in the order of the write selection signals SEL1 to SEL8. That is, supply periods are sequentially assigned to the signal lines 122 of each series from the first series of signal lines 122 to the eighth series of signal lines 122. As a result, the image signal S is sequentially supplied to the signal lines 122 of each series.

  Further, the high level periods of the precharge selection signals PSEL2 to PSEL8 are switched in accordance with the switching of the high level periods of the write selection signals SEL1 to SEL7. For example, the precharge selection signal PSEL2 transitions to a high level in synchronization with the timing at which the write selection signal SEL1 transitions to a high level, and transitions to a low level after a predetermined time has elapsed. Note that the precharge selection signal PSEL1 is maintained at a low level.

  In the first series supply period, that is, in the period in which the write selection signal SEL1 is at a high level, the precharge for the signal line 122 in the first series is not executed, so that the video voltage Vvidp is charged in the display of the previous horizontal scanning period H. The same video voltage Vvidp is applied again to the first series of signal lines 122. For this reason, the potential E122 [1] of the first-series signal line 122 hardly fluctuates. Therefore, the potential fluctuation of the capacitance line 124 due to capacitive coupling between the first-series signal line 122 and the capacitance line 124 hardly occurs. By the way, in order to create a state in which the potential E122 of the signal line 122 hardly fluctuates in the first horizontal scanning period H of each frame, a dummy pixel row that cannot be displayed is provided, and the same image signal S or gray level signal as in the raster display is provided. Is written to the signal line 122. Alternatively, before the first horizontal scanning period H of each frame starts, it is preferable to perform an operation such as writing the same image signal S or gray level signal as the raster display to the signal line 122.

  Further, in the first series supply period, precharge for the second series of signal lines 122 is performed in the second series precharge period in which the precharge selection signal PSEL2 is maintained at a high level. That is, the precharge signal PRC is supplied to the second line signal line 122 during the second line precharge period. Therefore, the potential E122 [2] of the signal line 122 of the second series transits from the video voltage Vvidp to the precharge voltage Vprcp as described with reference to FIG. Then, due to capacitive coupling between the second series signal line 122 and the capacitor line 124, a change in the potential E 122 [2] is propagated to the capacitor line 124, and a potential change occurs in the capacitor line 124. As described with reference to FIG. 4, the potential E <b> 124 of the capacitor line 124 decreases from the common voltage Vcom and returns to the common voltage Vcom again.

  In the second series supply period, that is, the period in which the write selection signal SEL2 is at the high level, the video voltage Vvidp is applied to the second series signal line 122 charged to the precharge voltage Vprcp. Therefore, the potential E122 [2] of the signal line 122 of the second series transits from the precharge voltage Vprcp to the video voltage Vvidp as described with reference to FIG. Then, due to capacitive coupling between the second series signal line 122 and the capacitor line 124, a change in the potential E 122 [2] is propagated to the capacitor line 124, and a potential change occurs in the capacitor line 124.

  However, in the second series supply period, the precharge for the third series signal line 122 is performed in the third series precharge period that overlaps with the second series supply period. For this reason, due to the counter noise effect described with reference to FIG. 4, the fluctuation of the potential E124 of the capacitor line 124 is suppressed compared to the supply period of the first series.

  For example, in the second series supply period, the precharge for the third series signal line 122 is executed while the precharge selection signal PSEL3 is at a high level. For this reason, the potential E122 [3] of the third series signal line 122 transitions from the video voltage Vvidp to the precharge voltage Vprcp. Then, due to capacitive coupling between the third series signal line 122 and the capacitor line 124, the fluctuation of the potential E 122 [3] propagates to the capacitor line 124, and the potential fluctuation occurs in the capacitor line 124. The potential fluctuation of the capacitor line 124 due to the fluctuation of the potential E122 [2] and the potential fluctuation of the capacitance line 124 due to the fluctuation of the potential E122 [3] in the opposite direction to the fluctuation of the potential E122 [2] are superimposed on each other. As described, the noise generated in the capacitor line 124 is canceled out.

  In the second series supply period, since the fluctuation of the potential E124 of the capacitor line 124 is suppressed compared to the first series supply period, the potential E124 of the capacitor line 124 is stabilized earlier. For this reason, the length T2 of the supply period of the second sequence can be made shorter than the length T1 of the supply period of the first sequence. Note that when the supply period ends before the potential E124 of the capacitor line 124 is stabilized, that is, before the potential E124 of the capacitor line 124 returns to the common voltage Vcom, the potential E124 of the capacitor line 124 becomes equal to the common voltage after the supply period ends. Return to Vcom. In this case, the potential of the pixel electrode 132 connected to the storage capacitor Cst also varies after the supply period ends. That is, after the supply period ends, the potential of the pixel electrode 132 changes from the video voltage Vvidp based on the image signal S. In this case, the pixel PX cannot accurately display the gradation specified by the image signal S.

  Therefore, in the first series supply period, the supply period ends before the potential E124 of the capacitor line 124 is stabilized by setting the length T1 of the supply period longer than the length T2 of the second series supply period. Suppress. As a result, the gradation specified by the image signal S can be accurately displayed also in each pixel PX of the first series in which the image signal S is supplied during the supply period of the first series.

  In the third series supply period to the seventh series supply period, similarly to the second series supply period, the fluctuation of the potential E124 of the capacitor line 124 is suppressed compared to the first series supply period due to the counter noise effect. Is done. As described above, the supply period from the second series to the seventh series is a supply period in which the image signal S is supplied to the signal line 122 to which the precharge signal PRC has already been supplied. It includes an overlap period with the precharge period for supplying the charge signal PRC.

  In an eighth series supply period, that is, a period in which the write selection signal SEL8 is at a high level, the video voltage Vvidp is applied to the eighth series signal line 122 charged to the precharge voltage Vprcp. For this reason, the potential E122 [8] of the eighth series signal line 122 transitions from the precharge voltage Vprcp to the video voltage Vvidp. Then, due to capacitive coupling between the signal line 122 and the capacitive line 124 of the eighth series, the fluctuation of the potential E122 [8] propagates to the capacitive line 124, and the potential fluctuation occurs in the capacitive line 124. For example, the potential E124 of the capacitor line 124 rises from the common voltage Vcom and returns to the common voltage Vcom again.

  Note that in the eighth series supply period, precharge for the other series of signal lines 122 is not executed. For this reason, the counter noise effect cannot be obtained in the supply period of the eighth series. As a result, in the supply period of the eighth series, the time until the potential E124 of the capacitor line 124 is stabilized is longer than in the supply period from the second series to the seventh series where the counter noise effect is obtained. Therefore, in the eighth series supply period, the supply period ends before the potential E124 of the capacitor line 124 is stabilized by making the length T3 of the supply period longer than the length T2 of the second series supply period. Suppress. As a result, the gradation specified by the image signal S can be accurately displayed also in each pixel PX of the eighth series in which the image signal S is supplied during the supply period of the eighth series.

  That is, the control circuit 280 makes the length T1 of the first series supply period and the length T3 of the eighth series supply period longer than the length T2 of the supply period from the second series to the seventh series. In the example shown in FIG. 5, the first series supply period is the first supply period among the eight supply periods for sequentially supplying the image signal S to each series of the eight series of signal lines 122. The supply period of the eighth series is the last supply period among the eight supply periods. The supply period from the second series to the seventh series is a supply period excluding the first supply period and the last supply period among the eight supply periods.

  That is, in the example shown in FIG. 5, the supply period of the first series is an example of the first supply period, the supply periods from the second series to the seventh series are examples of the predetermined supply period, and the eighth series The supply period is an example of the last supply period. Therefore, the control circuit 280 sets the lengths T1 and T3 of both the first supply period and the last supply period of the eight supply periods to the first supply period and the last supply of the eight supply periods. It is longer than the length T2 of the predetermined supply period excluding the period. Note that the control circuit 280 may make one of the first supply period and the last supply period of the eight supply periods longer than the predetermined supply period length T2.

  FIG. 6 is a diagram illustrating operation timing in the second horizontal scanning period H2. Detailed descriptions of operations similar to those described in FIG. 5 are omitted. The second horizontal scanning period H2 is a horizontal scanning period H for writing the video voltage Vvidp to the pixels PX in the second row. In the second horizontal scanning period H2, the potential of the scanning signal G2 supplied to the second scanning line 120 is set to a high level. The scanning signals G1, G3-G2160 supplied to the scanning lines 120 other than the second row are maintained at a low level.

  In the second horizontal scanning period H2, the order in which the image signals S are sequentially supplied to the signal lines 122 of each series from the first series to the eighth series is different from that in the first horizontal scanning period H1. For example, the high level periods of the write selection signals SEL1-SEL8 are switched in the order of the write selection signals SEL2-SEL8, SEL1. That is, the control circuit 280 varies the signal line 122 to which the image signal S is supplied in the first supply period in the two horizontal scanning periods H of the first horizontal scanning period H1 and the second horizontal scanning period H2. In addition, the control circuit 280 makes the signal line 122 to which the image signal S is supplied in the last supply period differ in the two horizontal scanning periods H of the first horizontal scanning period H1 and the second horizontal scanning period H2.

  The high-level periods of the precharge selection signals PSEL3-PSEL8 and PSEL1 are sequentially switched in accordance with the switching of the high-level periods of the write selection signals SEL2-SEL8. For example, the precharge selection signal PSEL3 transitions to a high level in synchronization with the timing at which the write selection signal SEL2 transitions to a high level, and transitions to a low level after a predetermined time has elapsed. Further, for example, the precharge selection signal PSEL1 changes to high level in synchronization with the timing at which the write selection signal SEL8 changes to high level, and changes to low level after a predetermined time has elapsed. Note that the precharge selection signal PSEL2 is maintained at a low level.

  Therefore, in the second horizontal scanning period H2, the counter noise effect cannot be obtained in the second series supply period which is the first supply period and the first series supply period which is the last supply period. On the other hand, a counter noise effect is obtained in the supply period from the third series to the eighth series. For this reason, the control circuit 280 makes the length T1 of the second series supply period and the length T3 of the first series supply period longer than the length T2 of the supply period from the third series to the eighth series. As a result, each pixel PX in each series can accurately display the gradation specified by the image signal S. The supply period from the third series to the eighth series shown in FIG. 6 is an example of a predetermined supply period.

  Further, since the electro-optical device 1 makes the signal line 122 to which the image signal S is supplied in the first supply period differ in the two horizontal scanning periods H, the electro-optical device 1 is the pixel PX to which the image signal S is supplied in the first supply period. Even when the gradation is not accurately displayed, it is possible to suppress fixing of the column of the pixels PX where the gradation is not accurately displayed. Similarly, since the electro-optical device 1 makes the signal line 122 to which the image signal S is supplied in the last supply period different in the two horizontal scanning periods H, the pixel PX to which the image signal S is supplied in the last supply period. Even when the gradation is not accurately displayed, it is possible to suppress fixing of the column of the pixels PX where the gradation is not accurately displayed.

  At the operation timings shown in FIGS. 5 and 6, the control circuit 280 performs the second series supply period for supplying the image signal S to the second series signal line 122, and the first supply period in the second horizontal scanning period H2. And assigned to a predetermined supply period in the first horizontal scanning period H1. Then, the control circuit 280 makes the length T1 of the first supply period longer than the length T2 of the predetermined supply period. Further, the precharge circuit 160 does not supply the precharge signal PRC to the second series of signal lines 122 in the second horizontal scanning period H2, and does not supply the second series of signal lines 122 in the first horizontal scanning period H1. To supply the precharge signal PRC. In the example shown in FIGS. 5 and 6, the second series of signal lines 122 is an example of the first signal lines 122 of the k signal lines 122, and the second horizontal scanning period H <b> 2 is 2 This is an example of the first horizontal scanning period H that is one of the two horizontal scanning periods H, and the first horizontal scanning period H1 is an example of the second horizontal scanning period H that is the other of the two horizontal scanning periods H. .

  FIG. 7 is a diagram illustrating the operation timing of the third horizontal scanning period H3. Detailed descriptions of operations similar to those described in FIG. 5 are omitted. The third horizontal scanning period H3 is a horizontal scanning period H for writing the video voltage Vvidp to the pixels PX in the third row. In the third horizontal scanning period H3, the potential of the scanning signal G3 supplied to the third scanning line 120 is set to a high level. The scanning signals G1, G2, and G4-G2160 supplied to the scanning lines 120 other than the third row are maintained at a low level.

  In the third horizontal scanning period H3, the order in which the image signals S are sequentially supplied to the signal lines 122 of each series from the first series to the eighth series is the first horizontal scanning period H1 and the second horizontal scanning period H2. And different. For example, the high level periods of the write selection signals SEL1-SEL8 are switched in the order of the write selection signals SEL3-SEL8, SEL1, SEL2. That is, the control circuit 280 varies the signal line 122 to which the image signal S is supplied in the first supply period in the three horizontal scanning periods H. In addition, the control circuit 280 varies the signal line 122 to which the image signal S is supplied in the last supply period in three horizontal scanning periods H.

  The high-level periods of the precharge selection signals PSEL4-PSEL8, PSEL1, and PSEL2 are sequentially switched in accordance with the switching of the high-level periods of the write selection signals SEL3-SEL8 and SEL1. For example, the precharge selection signal PSEL4 transitions to a high level in synchronization with the timing at which the write selection signal SEL3 transitions to a high level, and transitions to a low level after a predetermined time has elapsed. Further, for example, the precharge selection signal PSEL2 transitions to a high level in synchronization with the timing at which the write selection signal SEL1 transitions to a high level, and transitions to a low level after a predetermined time elapses. Note that the precharge selection signal PSEL3 is maintained at a low level.

  Therefore, in the third horizontal scanning period H3, the counter noise effect cannot be obtained in the third supply period that is the first supply period and the second supply period that is the last supply period. On the other hand, the counter noise effect is obtained in the supply period from the fourth series to the eighth series and the supply period of the first series. For this reason, the control circuit 280 sets the length T1 of the third series supply period and the length T3 of the second series supply period to the supply period from the fourth series to the eighth series and the supply period of the first series. It is longer than the length T2 of each supply period. As a result, each pixel PX in each series can accurately display the gradation specified by the image signal S. The supply period from the fourth series to the eighth series and the supply period of the first series shown in FIG. 7 are examples of the predetermined supply period.

  Further, since the electro-optical device 1 varies the signal line 122 to which the image signal S is supplied in the first supply period in three horizontal scanning periods H, the pixel PX to which the image signal S is supplied in the first supply period. Even when the gradation is not accurately displayed, it is possible to suppress fixing of the column of the pixels PX where the gradation is not accurately displayed. Similarly, since the electro-optical device 1 makes the signal line 122 to which the image signal S is supplied in the last supply period different in the three horizontal scanning periods H, the pixel PX to which the image signal S is supplied in the last supply period. Even when the gradation is not accurately displayed, it is possible to suppress fixing of the column of the pixels PX where the gradation is not accurately displayed.

  FIG. 8 is a diagram illustrating operation timings in the fourth horizontal scanning period H4. Detailed descriptions of operations similar to those described in FIG. 5 are omitted. The fourth horizontal scanning period H4 is a horizontal scanning period H for writing the video voltage Vvidp to the pixels PX in the fourth row. In the fourth horizontal scanning period H4, the potential of the scanning signal G4 supplied to the fourth scanning line 120 is set to a high level. The scanning signals G1-G3 and G5-G2160 supplied to the scanning lines 120 other than the fourth row are maintained at a low level.

  In the fourth horizontal scanning period H4, the order in which the image signals S are sequentially supplied to the signal lines 122 of each series from the first series to the eighth series is the first horizontal scanning period H1 to the third horizontal scanning period H3. It differs from each horizontal scanning period H up to. For example, the high level periods of the write selection signals SEL1-SEL8 are switched in the order of the write selection signals SEL4-SEL8, SEL1-SEL3. That is, the control circuit 280 varies the signal line 122 to which the image signal S is supplied in the first supply period in the four horizontal scanning periods H. Further, the control circuit 280 varies the signal line 122 to which the image signal S is supplied in the last supply period in the four horizontal scanning periods H.

  The high-level periods of the precharge selection signals PSEL5-PSEL8 and PSEL1-PSEL3 are sequentially switched in accordance with the switching of the high-level periods of the write selection signals SEL4-SEL8 and SEL1-SEL2. For example, the precharge selection signal PSEL5 transitions to a high level in synchronization with the timing at which the write selection signal SEL4 transitions to a high level, and transitions to a low level after a predetermined time has elapsed. Further, for example, the precharge selection signal PSEL3 transitions to a high level in synchronization with the timing at which the write selection signal SEL2 transitions to a high level, and transitions to a low level after a lapse of a predetermined time. Note that the precharge selection signal PSEL4 is maintained at a low level.

  Therefore, in the fourth horizontal scanning period H4, the counter noise effect cannot be obtained in the fourth supply period that is the first supply period and the third supply period that is the last supply period. In contrast, the counter noise effect is obtained in the supply period from the fifth series to the eighth series, the first series supply period, and the second series supply period. Therefore, the control circuit 280 sets the length T1 of the fourth series supply period and the length T3 of the third series supply period to the supply period from the fifth series to the eighth series, the supply period of the first series, and It is longer than the length T2 of each supply period of the supply period of the second series. As a result, each pixel PX in each series can accurately display the gradation specified by the image signal S. The supply period from the fifth series to the eighth series, the supply period of the first series, and the supply period of the second series shown in FIG. 8 are examples of predetermined supply periods.

  Further, since the electro-optical device 1 varies the signal line 122 to which the image signal S is supplied in the first supply period in the four horizontal scanning periods H, the pixel PX to which the image signal S is supplied in the first supply period. Even when the gradation is not accurately displayed, it is possible to suppress fixing of the column of the pixels PX where the gradation is not accurately displayed. Similarly, since the electro-optical device 1 makes the signal line 122 to which the image signal S is supplied in the last supply period different in the four horizontal scanning periods H, the pixel PX to which the image signal S is supplied in the last supply period. Even when the gradation is not accurately displayed, it is possible to suppress fixing of the column of the pixels PX where the gradation is not accurately displayed.

  FIG. 9 is a diagram illustrating the operation timing of the fifth horizontal scanning period H5. Detailed descriptions of operations similar to those described in FIG. 5 are omitted. The fifth horizontal scanning period H5 is a horizontal scanning period H for writing the video voltage Vvidp to the pixels PX in the fifth row. In the fifth horizontal scanning period H5, the potential of the scanning signal G5 supplied to the fifth scanning line 120 is set to a high level. The scanning signals G1-G4 and G6-G2160 supplied to the scanning lines 120 other than the fifth row are maintained at a low level.

  In the fifth horizontal scanning period H5, the order in which the image signals S are sequentially supplied to the signal lines 122 of each series from the first series to the eighth series is the first horizontal scanning period H1 to the fourth horizontal scanning period H4. It differs from each horizontal scanning period H up to. For example, the high level periods of the write selection signals SEL1-SEL8 are switched in the order of the write selection signals SEL5-SEL8, SEL1-SEL4. That is, the control circuit 280 varies the signal line 122 to which the image signal S is supplied in the first supply period in five horizontal scanning periods H. In addition, the control circuit 280 varies the signal line 122 to which the image signal S is supplied in the last supply period in five horizontal scanning periods H.

  The high level periods of the precharge selection signals PSEL6 to PSEL8 and PSEL1 to PSEL4 are sequentially switched in accordance with the switching of the high level periods of the write selection signals SEL5 to SEL8 and SEL1 to SEL3. For example, the precharge selection signal PSEL6 transitions to a high level in synchronization with the timing at which the write selection signal SEL5 transitions to a high level, and transitions to a low level after a predetermined time has elapsed. Further, for example, the precharge selection signal PSEL4 transitions to a high level in synchronization with the timing at which the write selection signal SEL3 transitions to a high level, and transitions to a low level after a predetermined time has elapsed. Note that the precharge selection signal PSEL5 is maintained at a low level.

  Therefore, in the fifth horizontal scanning period H5, the counter noise effect cannot be obtained in the fifth supply period, which is the first supply period, and the fourth supply period, which is the last supply period. On the other hand, the counter noise effect is obtained in the supply period from the sixth series to the eighth series and the supply period from the first series to the third series. For this reason, the control circuit 280 sets the length T1 of the fifth series supply period and the length T3 of the fourth series supply period to the supply period from the sixth series to the eighth series and the first series to the third series. The supply period is made longer than the length T2 of each supply period. As a result, each pixel PX in each series can accurately display the gradation specified by the image signal S. The supply period from the sixth series to the eighth series and the supply period from the first series to the third series shown in FIG. 9 are examples of a predetermined supply period.

  Further, since the electro-optical device 1 varies the signal line 122 to which the image signal S is supplied in the first supply period in five horizontal scanning periods H, the pixel PX to which the image signal S is supplied in the first supply period. Even when the gradation is not accurately displayed, it is possible to suppress fixing of the column of the pixels PX where the gradation is not accurately displayed. Similarly, since the electro-optical device 1 varies the signal line 122 to which the image signal S is supplied in the last supply period in five horizontal scanning periods H, the pixel PX to which the image signal S is supplied in the last supply period. Even when the gradation is not accurately displayed, it is possible to suppress fixing of the column of the pixels PX where the gradation is not accurately displayed.

  FIG. 10 is a diagram illustrating the operation timing of the sixth horizontal scanning period H6. Detailed descriptions of operations similar to those described in FIG. 5 are omitted. The sixth horizontal scanning period H6 is a horizontal scanning period H for writing the video voltage Vvidp to the pixels PX in the sixth row. In the sixth horizontal scanning period H6, the potential of the scanning signal G6 supplied to the sixth scanning line 120 is set to a high level. The scanning signals G1-G5 and G7-G2160 supplied to the scanning lines 120 other than the sixth row are maintained at a low level.

  In the sixth horizontal scanning period H6, the order in which the image signals S are sequentially supplied to the signal lines 122 of each series from the first series to the eighth series is the first horizontal scanning period H1 to the fifth horizontal scanning period H5. It differs from each horizontal scanning period H up to. For example, the high-level periods of the write selection signals SEL1-SEL8 are switched in the order of the write selection signals SEL6-SEL8, SEL1-SEL5. In other words, the control circuit 280 varies the signal line 122 to which the image signal S is supplied in the first supply period in the six horizontal scanning periods H. In addition, the control circuit 280 varies the signal line 122 to which the image signal S is supplied in the last supply period in the six horizontal scanning periods H.

  The high-level periods of the precharge selection signals PSEL7, PSEL8, and PSEL1-PSEL5 are sequentially switched in accordance with the switching of the high-level periods of the write selection signals SEL6-SEL8 and SEL1-SEL4. For example, the precharge selection signal PSEL7 transitions to a high level in synchronization with the timing at which the write selection signal SEL6 transitions to a high level, and transitions to a low level after a predetermined time has elapsed. For example, the precharge selection signal PSEL5 transitions to a high level in synchronization with the timing at which the write selection signal SEL4 transitions to a high level, and transitions to a low level after a predetermined time has elapsed. Note that the precharge selection signal PSEL6 is maintained at a low level.

  Therefore, in the sixth horizontal scanning period H6, the counter noise effect cannot be obtained in the sixth series supply period which is the first supply period and the fifth series supply period which is the last supply period. In contrast, the counter noise effect is obtained in the seventh series supply period, the eighth series supply period, and the first to fourth series supply periods. Therefore, the control circuit 280 sets the length T1 of the sixth series supply period and the length T3 of the fifth series supply period from the seventh series supply period, the eighth series supply period, and the first series to the first series. The supply period up to four lines is longer than the length T2 of each supply period. As a result, each pixel PX in each series can accurately display the gradation specified by the image signal S. Note that the seventh series supply period, the eighth series supply period, and the first series to fourth supply periods shown in FIG. 10 are examples of a predetermined supply period.

  Further, since the electro-optical device 1 varies the signal line 122 to which the image signal S is supplied in the first supply period in the six horizontal scanning periods H, the pixel PX to which the image signal S is supplied in the first supply period. Even when the gradation is not accurately displayed, it is possible to suppress fixing of the column of the pixels PX where the gradation is not accurately displayed. Similarly, since the electro-optical device 1 varies the signal line 122 to which the image signal S is supplied in the last supply period in the six horizontal scanning periods H, the pixel PX to which the image signal S is supplied in the last supply period. Even when the gradation is not accurately displayed, it is possible to suppress fixing of the column of the pixels PX where the gradation is not accurately displayed.

  FIG. 11 is a diagram illustrating the operation timing of the seventh horizontal scanning period H7. Detailed descriptions of operations similar to those described in FIG. 5 are omitted. The seventh horizontal scanning period H7 is a horizontal scanning period H for writing the video voltage Vvidp to the pixels PX in the seventh row. In the seventh horizontal scanning period H7, the potential of the scanning signal G7 supplied to the seventh scanning line 120 is set to a high level. The scanning signals G1-G6 and G8-G2160 supplied to the scanning lines 120 other than the seventh row are maintained at a low level.

  In the seventh horizontal scanning period H7, the order in which the image signals S are sequentially supplied to the signal lines 122 of each series from the first series to the eighth series is the first horizontal scanning period H1 to the sixth horizontal scanning period H6. It differs from each horizontal scanning period H up to. For example, the high level periods of the write selection signals SEL1-SEL8 are switched in the order of the write selection signals SEL7, SEL8, SEL1-SEL6. In other words, the control circuit 280 varies the signal line 122 to which the image signal S is supplied in the first supply period in the seven horizontal scanning periods H. In addition, the control circuit 280 varies the signal line 122 to which the image signal S is supplied in the last supply period in the seven horizontal scanning periods H.

  The high level periods of the precharge selection signals PSEL8 and PSEL1 to PSEL6 are sequentially switched in accordance with the switching of the high level periods of the write selection signals SEL7, SEL8 and SEL1 to SEL5. For example, the precharge selection signal PSEL8 transitions to a high level in synchronization with the timing at which the write selection signal SEL7 transitions to a high level, and transitions to a low level after a predetermined time has elapsed. For example, the precharge selection signal PSEL6 transitions to a high level in synchronization with the timing at which the write selection signal SEL5 transitions to a high level, and transitions to a low level after a predetermined time has elapsed. Note that the precharge selection signal PSEL7 is maintained at a low level.

  Therefore, in the seventh horizontal scanning period H7, the counter noise effect cannot be obtained in the seventh series supply period which is the first supply period and the sixth series supply period which is the last supply period. On the other hand, the counter noise effect is obtained in the supply period of the eighth series and the supply periods from the first series to the fifth series. Therefore, the control circuit 280 sets the length T1 of the seventh series supply period and the length T3 of the sixth series supply period to the eighth series supply period and the supply periods from the first series to the fifth series. It is longer than the length T2 of each supply period. As a result, each pixel PX in each series can accurately display the gradation specified by the image signal S. Note that the supply period of the eighth series and the supply period from the first series to the fifth series shown in FIG. 11 are examples of a predetermined supply period.

  Further, since the electro-optical device 1 varies the signal line 122 to which the image signal S is supplied in the first supply period in the seven horizontal scanning periods H, the pixel PX to which the image signal S is supplied in the first supply period. Even when the gradation is not accurately displayed, it is possible to suppress fixing of the column of the pixels PX where the gradation is not accurately displayed. Similarly, since the electro-optical device 1 varies the signal line 122 to which the image signal S is supplied in the last supply period in the seven horizontal scanning periods H, the pixel PX to which the image signal S is supplied in the last supply period. Even when the gradation is not accurately displayed, it is possible to suppress fixing of the column of the pixels PX where the gradation is not accurately displayed.

  FIG. 12 is a diagram showing the operation timing in the eighth horizontal scanning period H8. Detailed descriptions of operations similar to those described in FIG. 5 are omitted. The eighth horizontal scanning period H8 is a horizontal scanning period H for writing the video voltage Vvidp to the pixels PX in the eighth row. In the eighth horizontal scanning period H8, the potential of the scanning signal G8 supplied to the eighth scanning line 120 is set to a high level. The scanning signals G1-G7 and G9-G2160 supplied to the scanning lines 120 other than the eighth row are maintained at a low level.

  In the eighth horizontal scanning period H8, the order when the image signals S are sequentially supplied to the signal lines 122 of each series from the first series to the eighth series is the first horizontal scanning period H1 to the seventh horizontal scanning period H7. It differs from each horizontal scanning period H up to. For example, the write selection signals SEL1 to SEL8 are switched in the order of the write selection signals SEL8 and SEL1 to SEL7 during the high level period. In other words, the control circuit 280 varies the signal line 122 to which the image signal S is supplied in the first supply period in the eight horizontal scanning periods H. In addition, the control circuit 280 varies the signal line 122 to which the image signal S is supplied in the last supply period in the eight horizontal scanning periods H. That is, the control circuit 280 changes the signal line 122 to which the image signal S is supplied in the first supply period in the k horizontal scanning periods H, and the signal line 122 to which the image signal S is supplied in the last supply period. Are different in k horizontal scanning periods H.

  The high level periods of the precharge selection signals PSEL1 to PSEL7 are sequentially switched in accordance with the switching of the high level periods of the write selection signals SEL8 and SEL1 to SEL6. For example, the precharge selection signal PSEL1 transitions to a high level in synchronization with the timing at which the write selection signal SEL8 transitions to a high level, and transitions to a low level after a predetermined time has elapsed. Further, for example, the precharge selection signal PSEL7 transitions to a high level in synchronization with the timing at which the write selection signal SEL6 transitions to a high level, and transitions to a low level after a predetermined time has elapsed. Note that the precharge selection signal PSEL8 is maintained at a low level.

  Therefore, in the eighth horizontal scanning period H8, the counter noise effect cannot be obtained in the eighth series supply period which is the first supply period and the seventh series supply period which is the last supply period. On the other hand, the counter noise effect is obtained in the supply period from the first series to the sixth series. For this reason, the control circuit 280 makes the length T1 of the eighth series supply period and the length T3 of the seventh series supply period longer than the length T2 of the supply period from the first series to the sixth series. As a result, each pixel PX in each series can accurately display the gradation specified by the image signal S. In addition, the supply period from the 1st series to the 6th series shown in FIG. 12 is an example of a predetermined supply period.

  Further, since the electro-optical device 1 changes the signal line 122 to which the image signal S is supplied in the first supply period in the eight horizontal scanning periods H, the pixel PX to which the image signal S is supplied in the first supply period. Even when the gradation is not accurately displayed, it is possible to suppress fixing of the column of the pixels PX where the gradation is not accurately displayed. Similarly, since the electro-optical device 1 makes the signal line 122 to which the image signal S is supplied in the last supply period different in the eight horizontal scanning periods H, the pixel PX to which the image signal S is supplied in the last supply period. Even when the gradation is not accurately displayed, it is possible to suppress fixing of the column of the pixels PX where the gradation is not accurately displayed.

  That is, at the operation timing shown in FIGS. 5 to 12, the control circuit 280 includes the precharge period in the supply period in which the image signal S is supplied to the signal line 122 of the series to which the precharge signal PRC has already been supplied. The supply period not including the overlap period is longer than the supply period including the overlap period with the precharge period. In addition, the control circuit 280 sets the supply period in which the image signal S is supplied to the signal line 122 of the series to which the precharge signal PRC is not supplied, of the supply period including the overlap period with the precharge period. Is longer than the supply period in which the image signal S is supplied to the signal line 122 in the column where the signal is already supplied.

  In the horizontal scanning period H other than the horizontal scanning period H from the first horizontal scanning period H1 to the eighth horizontal scanning period H8, except for the scanning signal G for selecting the row of the pixel PX to which the video voltage Vvidp is to be written, FIG. To any one of the operation timings shown in FIG. The vertical scanning period may include a horizontal scanning period H that operates at an operation timing different from the operation timings shown in FIGS. 5 to 12, for example, a horizontal scanning period H in which precharge is not executed.

  The operation timing of each horizontal scanning period H of the electro-optical device 1 when performing raster display with negative polarity driving is the same as that in the description of FIGS. 5 to 12 with the video voltage Vvidp and the precharge voltage Vprcp at the time of negative polarity driving. This is explained by replacing the video voltage and the precharge voltage respectively. During negative polarity driving, the potential E122 of the signal line 122 hardly fluctuates depending on the gradation.

  FIG. 13 is a flowchart illustrating an example of the operation of the electro-optical device 1 according to the first embodiment. The operation illustrated in FIG. 13 is an example of a driving method of the electro-optical device 1. The operation shown in FIG. 13 is an example of a driving method of the electro-optical device 1 when setting the length of each of eight supply periods, that is, k supply periods in each horizontal scanning period H. . In each horizontal scanning period H, the electro-optical device 1 repeats the operation illustrated in FIG. 13 until all the lengths of the k supply periods are set.

First, in step S100, the electro-optical device 1 determines whether the supply period of the signal line 122 to be driven is the first supply period among the k supply periods. When the supply period of the signal line 122 to be driven is the first supply period, the electro-optical device 1 sets the supply period of the signal line 122 to be driven to the length T1 in step S200. On the other hand, when the supply period of the signal line 122 to be driven is not the first supply period, the operation of the electro-optical device 1 proceeds to step S120.
In step S120, the electro-optical device 1 determines whether the supply period of the signal line 122 to be driven is the last supply period among the k supply periods. When the supply period of the signal line 122 to be driven is the last supply period, the electro-optical device 1 sets the supply period of the signal line 122 to be driven to the length T3 in step S220. On the other hand, when the supply period of the signal line 122 to be driven is not the last supply period, the electro-optical device 1 sets the supply period of the signal line 122 to be driven to a length T2 shorter than the lengths T1 and T3 in step S240. Set to.

  That is, the electro-optical device 1 performs the first supply period and the last supply period among the k supply periods for sequentially supplying the image signal S to each of the k signal lines 122 in each horizontal scanning period H. , Longer than one or a plurality of predetermined supply periods excluding the first supply period and the last supply period among the k supply periods.

  The operation of the electro-optical device 1 is not limited to the example illustrated in FIG. For example, steps S120 and S220 may be omitted. Alternatively, steps S100 and S200 may be omitted. That is, in each horizontal scanning period H, the electro-optical device 1 performs one of the first supply period and the last supply period among the k supply periods, and the first supply period and the last supply period among the k supply periods. It may be longer than one or a plurality of predetermined supply periods excluding the supply period.

  As described above, in the first embodiment, in the horizontal scanning period H, the control circuit 280 includes the first supply period and the last of the k supply periods for sequentially supplying the image signal S to each of the k signal lines 122. Is set to be longer than one or a plurality of predetermined supply periods excluding the first supply period and the last supply period among the k supply periods.

  For example, the predetermined supply period is a supply period in which the image signal S is supplied to the signal line 122 to which the precharge signal PRC has already been supplied, and a precharge period in which the precharge signal PRC is supplied to the other signal lines 122. Including overlapping periods. For this reason, in a predetermined supply period, a counter noise effect that cancels noise superimposed on the capacitor line 124 is obtained.

  Note that the first supply period and the last supply period in which the counter noise effect is not obtained are set longer than the predetermined supply period in which the counter noise effect is obtained as described above. As a result, the electro-optical device 1 can suppress the end of the first supply period and the last supply period in which the counter noise effect cannot be obtained before the capacitance line 124 is stabilized. Accordingly, even in the pixel PX to which the image signal S is supplied in the first supply period and the last supply period, the gradation specified by the image signal S can be accurately displayed. That is, the electro-optical device 1 can suppress display unevenness and improve display quality.

  Even when one of the first supply period and the last supply period is longer than one or a plurality of predetermined supply periods excluding the first supply period and the last supply period of the k supply periods, the supply period The occurrence of display unevenness can be suppressed as compared with the case where the length of the display is not adjusted. That is, the display quality of the electro-optical device 1 can be improved.

  Further, the control circuit 280 varies the signal line 122 to which the image signal S is supplied in the first supply period in two horizontal scanning periods H. For this reason, even when the gradation is not accurately displayed in the pixel PX to which the image signal S is supplied in the first supply period, it is possible to suppress fixing of the column of the pixels PX in which the gradation is not accurately displayed. Similarly, the control circuit 280 varies the signal line 122 to which the image signal S is supplied in the last supply period in the two horizontal scanning periods H. For this reason, even when the gradation is not accurately displayed in the pixel PX to which the image signal S is supplied in the last supply period, it is possible to suppress fixing of the column of the pixels PX in which the gradation is not accurately displayed.

  In addition, the control circuit 280 varies the signal line 122 to which the image signal S is supplied in the first supply period in k horizontal scanning periods H. For this reason, even when the gradation is not accurately displayed in the pixel PX to which the image signal S is supplied in the first supply period, it is possible to suppress fixing of the column of the pixels PX in which the gradation is not accurately displayed. Similarly, the control circuit 280 changes the signal line 122 to which the image signal S is supplied in the last supply period in k horizontal scanning periods H. For this reason, even when the gradation is not accurately displayed in the pixel PX to which the image signal S is supplied in the last supply period, it is possible to suppress fixing of the column of the pixels PX in which the gradation is not accurately displayed.

Second Embodiment
The configuration and operation of the electro-optical device 1 according to the second embodiment are the same as those of the electro-optical device 1 according to the first embodiment described above except for the timing when the control circuit 280 supplies the precharge signal PRC to the signal line 122. .

  FIG. 14 is a diagram showing the operation timing of the first horizontal scanning period H1 in the second embodiment of the present invention. Detailed descriptions of operations similar to those described in FIG. 5 are omitted.

  In the first horizontal scanning period H1, similarly to the operation timing shown in FIG. 5, the high-level periods of the write selection signals SEL1-SEL8 are switched in the order of the write selection signals SEL1-SEL8. Further, the high level periods of the precharge selection signals PSEL2 to PSEL8 are switched in order in accordance with the switching of the high level periods of the write selection signals SEL1 to SEL7. In the example illustrated in FIG. 14, the order in which the high-level periods of the precharge selection signals PSEL2 to PSEL8 are switched is the same as the operation timing illustrated in FIG. 5, but the switching timing is different from the operation timing illustrated in FIG. 5. .

  For example, the precharge selection signal PSEL2 changes in synchronization with the write selection signal SEL1, similarly to the operation timing shown in FIG. However, the precharge selection signal PSEL2 changes to the high level before the write selection signal SEL1 changes to the high level. The precharge selection signal PSEL2 changes to the low level before the write selection signal SEL1 changes to the low level.

  Further, for example, the precharge selection signal PSEL8 changes in synchronization with the write selection signal SEL7, similarly to the operation timing shown in FIG. However, the precharge selection signal PSEL8 transitions to the high level after the transition of the write selection signal SEL6 to the low level and before the write selection signal SEL7 transitions to the high level. Then, the precharge selection signal PSEL8 changes to the low level before the write selection signal SEL7 changes to the low level. Each of the precharge selection signals PSEL3 to PSEL7 also changes at the same timing as the precharge selection signal PSEL8 with respect to the synchronous write selection signal SEL.

  That is, in the second embodiment, the control circuit 280 precedes the first supply period with the precharge period overlapping the first supply period, leaving a period overlapping with the first supply period. In addition, the control circuit 280 precedes a predetermined supply period with a precharge period overlapping with a predetermined supply period such as a second series of supply periods, leaving a period overlapping with the predetermined supply period.

  If the driving capability of the precharge switch SWp is low, the counter noise effect may not be sufficiently obtained. For this reason, in the second embodiment, the time until the fluctuation of the potential E124 of the capacitor line 124 becomes gentler by making the precharge period precede the supply period than in the case where the precharge period is not preceded by the supply period. Secure. As a result, the supply period can be prevented from ending before the potential E124 of the capacitor line 124 is stabilized. Therefore, each pixel PX can accurately display the gradation specified by the image signal S.

<Modification>
Each form illustrated above can be variously modified. Specific modifications are exemplified below. Two or more aspects arbitrarily selected from the following examples can be appropriately combined as long as they do not contradict each other.

<Modification 1>
15 and 16 are diagrams illustrating operation timings of the electro-optical device 1 according to the first modification of the first embodiment. 15 and 16 show the operation timing of the electro-optical device 1 when raster display is executed by positive polarity driving. In the first modification, precharge is performed every other supply period. That is, the precharge may be executed in accordance with one or a plurality of predetermined supply periods excluding the last supply period among the k supply periods. In the example shown in FIGS. 15 and 16, the precharge circuit 160 includes h pieces corresponding to the first to (k−1) th supply periods of the k supply periods included in the horizontal scanning period H. In each of the precharge periods, the precharge signal PRC is supplied to one of the k signal lines 122. However, h is an integer of 2 or more and k-1 or less. Further, the control circuit 280 sets the supply period corresponding to the first precharge period out of the k supply periods included in the horizontal scanning period H from the supply period corresponding to the second precharge period. Lengthen.

  FIG. 15 is a diagram illustrating the operation timing of the first horizontal scanning period H1 in Modification 1 of the first embodiment. Detailed descriptions of operations similar to those described in FIG. 5 are omitted.

  In the first horizontal scanning period H1, similarly to the operation timing shown in FIG. 5, the high-level periods of the write selection signals SEL1-SEL8 are switched in the order of the write selection signals SEL1-SEL8. Further, the high-level periods of the precharge selection signals PSEL3, PSEL5, and PSEL7 are sequentially switched in accordance with the switching of the high-level periods of the write selection signals SEL1, SEL3, and SEL5. That is, in the first horizontal scanning period H1 of Modification 1, the precharge signal PRC is sequentially supplied to the odd-numbered signal lines 122.

  For example, the precharge selection signal PSEL3 transitions to a high level in synchronization with the timing at which the write selection signal SEL1 transitions to a high level, and transitions to a low level after a predetermined time has elapsed. Further, for example, the precharge selection signal PSEL5 transitions to a high level in synchronization with the timing at which the write selection signal SEL3 transitions to a high level, and transitions to a low level after a predetermined time elapses. Further, for example, the precharge selection signal PSEL7 transitions to the high level in synchronization with the timing at which the write selection signal SEL5 transitions to the high level, and transitions to the low level after a lapse of a predetermined time. Note that the precharge selection signals PSEL1, PSEL2, PSEL4, PSEL6, and PSEL8 are maintained at a low level.

  Therefore, in the first horizontal scanning period H1 of the first modification, the counter noise effect is produced in the first series supply period that is the first supply period and the seventh series supply period that is the last supply period in the odd series. I can't get it. On the other hand, the counter noise effect is obtained in the third series supply period and the fifth series supply period. Therefore, the control circuit 280 determines the length T1 of the first series supply period and the length T4 of the seventh series supply period as the length of each supply period of the third series supply period and the fifth series supply period. Longer than T2. As a result, each pixel PX in each series can accurately display the gradation specified by the image signal S. Note that the third series of supply periods and the fifth series of supply periods shown in FIG. 15 are examples of predetermined supply periods.

  In the case of raster display, the potential E122 of the signal line 122 hardly changes during the even-numbered supply period in the first horizontal scanning period H1 of Modification 1. Therefore, the potential E124 of the capacitor line 124 hardly changes. Therefore, the length of the even series supply period, for example, the length T3 of the eighth series supply period, which is the last supply period, is the length of each supply period of the third series supply period and the fifth series supply period. It may be the same as T2.

  FIG. 16 is a diagram illustrating the operation timing of the second horizontal scanning period H2 in the first modification. Detailed descriptions of operations similar to those described in FIGS. 5 and 6 are omitted.

  In the second horizontal scanning period H2, similarly to the operation timing shown in FIG. 5, the high-level periods of the write selection signals SEL1-SEL8 are switched in the order of the write selection signals SEL1-SEL8. Further, the high-level periods of the precharge selection signals PSEL4, PSEL6, and PSEL8 are sequentially switched in accordance with the switching of the high-level periods of the write selection signals SEL2, SEL4, and SEL6. That is, in the second horizontal scanning period H2 of the first modification, the precharge signal PRC is sequentially supplied to the even-numbered signal lines 122.

  For example, the precharge selection signal PSEL4 transitions to a high level in synchronization with the timing at which the write selection signal SEL2 transitions to a high level, and transitions to a low level after a predetermined time has elapsed. Further, for example, the precharge selection signal PSEL6 transitions to a high level in synchronization with the timing at which the write selection signal SEL4 transitions to a high level, and transitions to a low level after a predetermined time elapses. Further, for example, the precharge selection signal PSEL8 transitions to a high level in synchronization with the timing at which the write selection signal SEL6 transitions to a high level, and transitions to a low level after a predetermined time elapses. Note that the precharge selection signals PSEL1, PSEL2, PSEL3, PSEL5, and PSEL7 are maintained at a low level.

  Therefore, in the second horizontal scanning period H2 of the first modification, the counter noise effect is produced in the second series supply period which is the first supply period in the even series and the eighth series supply period which is the last supply period. I can't get it. On the other hand, the counter noise effect is obtained in the fourth series supply period and the sixth series supply period. Therefore, the control circuit 280 sets the length T5 of the second series supply period and the length T3 of the eighth series supply period to the length of each supply period of the fourth series supply period and the sixth series supply period. Longer than T2. As a result, each pixel PX in each series can accurately display the gradation specified by the image signal S. Note that the fourth series supply period and the sixth series supply period shown in FIG. 15 are examples of a predetermined supply period.

  Further, in the case of raster display, the potential E122 of the signal line 122 hardly changes during the odd series supply period in the second horizontal scanning period H2 of Modification 1, and therefore the potential E124 of the capacitor line 124 hardly changes. Therefore, the length of the odd series supply period, for example, the length T1 of the first series supply period, which is the first supply period, is the length of each supply period of the fourth series supply period and the sixth series supply period. It may be the same as T2.

  Also in the modification 1, the same effect as 1st Embodiment mentioned above can be acquired. Note that Modification 1 may be applied to the second embodiment described above. That is, also in the first modification, the control circuit 280 may precede the precharge period with respect to the synchronized write selection signal SEL, leaving an overlapping period.

  Also in the first modification, the control circuit 280 may vary the signal line 122 to which the image signal S is supplied in the first supply period in the odd series in a plurality of horizontal scanning periods H. Further, the control circuit 280 may vary the signal line 122 to which the image signal S is supplied in the first supply period in the even-number series in a plurality of horizontal scanning periods H. Further, the control circuit 280 may vary the signal line 122 to which the image signal S is supplied in the last supply period in the odd series in a plurality of horizontal scanning periods H. Further, the control circuit 280 may change the signal line 122 to which the image signal S is supplied in the last supply period in the even-number series in a plurality of horizontal scanning periods H.

<Modification 2>
FIG. 2 described above illustrates an example in which the other ends of the precharge switches SWp1 to SWp4160 are connected to each other. However, the connection relationship between the other ends of the precharge switches SWp1 to SWp4160 is not limited to the example illustrated in FIG. For example, the other ends of the precharge switches SWp connected to the signal lines 122 in the odd-numbered columns are connected to each other, and the other ends of the precharge switches SWp connected to the signal lines 122 in the even-numbered columns are connected to each other. Also good.

  In this case, in the normal operation of the electro-optical device 1, the precharge voltage control circuit 260 and the other end of the precharge switch SWp connected to the signal line 122 in the odd-numbered column and the signal line 122 in the even-numbered column. The precharge signal PRC is supplied to both of the other ends of the precharge switch SWp connected to. When the electro-optical device 1 is tested, for example, a test circuit (not shown) connects the other end of the precharge switch SWp connected to the signal line 122 in the odd-numbered column to the signal line 122 in the even-numbered column. Is electrically insulated from the other end of the precharge switch SWp. The test circuit is different between the other end of the precharge switch SWp connected to the signal line 122 in the odd-numbered column and the other end of the precharge switch SWp connected to the signal line 122 in the even-numbered column. Supply level test signal. In this case, a short circuit between adjacent signal lines 122 can be easily detected.

<Modification 3>
In FIG. 2 described above, the example in which the plurality of signal lines 122 are classified into the signal line group including the k signal lines 122 is shown. However, the plurality of signal lines 122 are not classified into the plurality of signal line groups. Also good. For example, the electro-optical device 1 may have k signal lines 122 to which the image signal S is sequentially supplied. That is, in the block diagram shown in FIG. 2, the signal lines 122 and the pixels PX from the 9th column to the 4160th column, the write selection circuit SUv other than the write selection circuit SUv1, and the precharge selection other than the precharge selection circuit SUp1 The circuit SUp may be omitted.

<Modification 4>
In the first embodiment and the second embodiment described above, the apparatus using the liquid crystal is exemplified as the electro-optical device, but the present invention is not limited to this. In other words, any electro-optical device using an electro-optical material whose optical characteristics change depending on electric energy may be used. Note that the electro-optical material is a material whose optical characteristics such as transmittance and luminance change when an electric signal such as a current signal or a voltage signal is supplied. For example, the present invention can be applied to a display panel using a light emitting element such as an organic EL (ElecTroLuminescent), an inorganic EL, or a light emitting polymer, similarly to the first embodiment and the second embodiment described above.

  Similarly to the above-described first and second embodiments, an electrophoretic display panel using a microcapsule including a colored liquid and white particles dispersed in the liquid as an electro-optical material is used. The present invention can be applied. Furthermore, the present invention also applies to a twist ball display panel using a twist ball painted in a different color for each region having different polarities as an electro-optical material, as in the first and second embodiments described above. Can be applied. The present invention can also be applied to various electro-optical devices such as a toner display panel using black toner as an electro-optical material, as in the first and second embodiments described above.

<Modification 5>
In the development process of the present invention, the signal line 122 and the capacitor line 124 are visually recognized as display unevenness due to the noise caused by the transition operation in which the precharge switch SWp transitions from the conductive state to the non-conductive state. It is known that there are cases. Hereinafter, the transition operation in which the precharge switch SWp transitions from the conductive state to the nonconductive state is also referred to as an off operation of the precharge switch SWp.
In Modification 5, a method for suppressing the occurrence of display unevenness will be described.

In FIG. 5 of the first embodiment described above, in the first series supply period, precharge for the second series of signal lines 122 is executed in the second series of precharge periods. The end time of the first series supply period, that is, the timing immediately after the write selection signal SEL1 transitions to the low level is the end time of the second series precharge period, that is, the precharge selection signal PSEL2 is at the low level. It is later than the timing immediately after transition to. On the other hand, the end time of the second series supply period and the end time of the third series precharge period are substantially the same.
The inventor of the present application determines that the end time of the nth series supply period is later than the end time of the n + a series precharge period executed in a period overlapping with the nth series supply period. Compared with the case where the end time of the n-th series supply period coincides with the end time of the n + a-th series precharge period executed overlapping with the n-th series supply period, the precharge switch SWp is turned off. As a result, it has been found that the influence of noise on the signal line 122 and the capacitor line 124 is increased. However, n is an integer greater than or equal to 1, and a is an integer greater than or equal to 1. Note that the influence of noise on the signal line 122 and the capacitor line 124 due to the turning-off operation of the precharge switch SWp is executed by overlapping the end time of the nth series supply period with the nth series supply period. It has been found that even if it is earlier than the end time of the n + a series precharge period, it is suppressed.

Therefore, in order to suppress the influence due to noise associated with the off operation of the precharge switch SWp, in FIG. 5, the end time of the second series precharge period is substantially matched with the end time of the first series supply period. Also good. Similarly, in FIG. 6, the end time of the third series precharge period may be substantially matched with the end time of the second series supply period. Similarly, in FIG. 7, the end time of the fourth series precharge period may be substantially matched with the end time of the third series supply period. Similarly, in FIG. 8, the end time of the fifth series of precharge periods may be substantially matched with the end time of the fourth series of supply periods. Similarly, in FIG. 9, the end time of the sixth series precharge period may substantially coincide with the end time of the fifth series supply period. Similarly, in FIG. 10, the end time of the seventh series precharge period may be substantially matched with the end time of the sixth series supply period. Similarly, in FIG. 11, the end time of the eighth series precharge period may substantially coincide with the end time of the seventh series supply period. Similarly, in FIG. 12, the end time of the first series of precharge periods may be substantially matched with the end time of the eighth series of supply periods.
In this way, the time difference between the end time of the supply period for a certain series and the end time of the precharge period executed with overlapping periods is aligned, or the end time of the supply period is executed with overlapping periods. Display unevenness can be suppressed by using a configuration that is earlier than the end time of the precharge period.

<Application example>
The present invention can be used in various electronic devices. 17 to 19 exemplify specific forms of electronic devices to which the present invention is applied.

  FIG. 17 is an explanatory diagram illustrating an example of an electronic device. FIG. 17 is a perspective view of a portable personal computer 2000 that employs the electro-optical device 1. The personal computer 2000 includes an electro-optical device 1 that displays various images, and a main body 2010 on which a power switch 2001 and a keyboard 2002 are installed.

  FIG. 18 is an explanatory diagram illustrating another example of an electronic device. FIG. 18 is a perspective view of the mobile phone 3000. The cellular phone 3000 includes a plurality of operation buttons 3001 and scroll buttons 3002, and the electro-optical device 1 that displays various images. By operating the scroll button 3002, the screen displayed on the electro-optical device 1 is scrolled.

  FIG. 19 is an explanatory diagram illustrating another example of an electronic device. FIG. 19 is a schematic diagram illustrating a configuration of a projection display device 4000 that employs the electro-optical device 1. The projection display device 4000 is a three-plate projector, for example. An electro-optical device 1R shown in FIG. 19 is an electro-optical device 1 corresponding to a red display color, an electro-optical device 1G is an electro-optical device 1 corresponding to a green display color, and an electro-optical device 1B is The electro-optical device 1 corresponds to a blue display color.

  In other words, the projection display device 4000 includes three electro-optical devices 1R, 1G, and 1B that respectively correspond to red, green, and blue display colors. The illumination optical system 4001 supplies the red component r of the light emitted from the illumination device 4002 that is a light source to the electro-optical device 1R, the green component g to the electro-optical device 1G, and the blue component b to the electro-optical device 1B. To supply. Each electro-optical device 1R, 1G, 1B functions as an optical modulator such as a light valve that modulates each monochromatic light supplied from the illumination optical system 4001 in accordance with a display image. The projection optical system 4003 synthesizes light emitted from the electro-optical devices 1R, 1G, and 1B and projects the combined light onto the projection surface 4004. That is, the present invention can also be applied to a liquid crystal projector.

  Note that examples of electronic devices to which the present invention is applied include personal digital assistants (PDAs) in addition to the devices illustrated in FIGS. 1 and 17 to 19. In addition, there are a digital still camera, a television, a video camera, a car navigation device, a vehicle-mounted display (instrument panel), an electronic notebook, electronic paper, a calculator, a word processor, a workstation, a video phone, and a POS terminal. Furthermore, there are a printer, a scanner, a copying machine, a video player, a device equipped with a touch panel, and the like.

  DESCRIPTION OF SYMBOLS 1, 1B, 1G, 1R ... Electro-optical device, 100 ... Electro-optical panel, 120 ... Scanning line, 122 ... Signal line, 124 ... Capacitance line, 130 ... Liquid crystal element, 132 ... Pixel electrode, 134 ... Common electrode, 136 ... Liquid crystal, 140 ... Image signal circuit, 160 ... Precharge circuit, 180 ... Scanning line drive circuit, 200 ... Drive integrated circuit, 240 ... Signal line drive circuit, 260 ... Precharge voltage control circuit, 280 ... Control circuit, 300 ... Flexible circuit board, 2000 ... personal computer, 2001 ... power switch, 2002 ... keyboard, 2010 ... main body, 3000 ... mobile phone, 3001 ... operation button, 3002 ... scroll button, 4000 ... projection type display device, 4001 ... illumination optical system , 4002 ... Illumination device, 4003 ... Projection optical system, 4004 ... Projection surface, Cst Storage capacitor, PX ... pixel, SUp ... precharge selection circuit, SUV ... write select circuit, SWp ... precharge switch, SWv ... write switches, TRh ... pixel transistor.

Claims (15)

A plurality of scan lines;
k signal lines (k is an integer of 3 or more);
A reference line to which a reference potential is applied;
A pixel that is arranged corresponding to each intersection of the plurality of scanning lines and the k signal lines, includes a storage capacitor connected to the reference line, and holds a potential corresponding to an image signal in the storage capacitor; ,
An image signal circuit for sequentially supplying image signals to the k signal lines in k supply periods based on k selection signals for sequentially selecting the k signal lines in a horizontal scanning period;
A precharge circuit for supplying a precharge signal in a predetermined order to a signal line before the image signal circuit of the k signal lines supplies an image signal in the horizontal scanning period;
In the horizontal scanning period, at least one of the first supply period and the last supply period among the k supply periods for sequentially supplying the image signals to the k signal lines is set to the k supply lines. A control circuit for controlling the k selection signals so as to be longer than a predetermined supply period excluding the first supply period and the last supply period in a period;
An electro-optical device comprising: The control circuit controls the k selection signals so that both the first supply period and the last supply period are longer than the predetermined supply period;
The electro-optical device according to claim 1. The predetermined supply period is a supply period for supplying an image signal to a signal line to which a precharge signal has already been supplied, and includes an overlap period with a precharge period for supplying a precharge signal to another signal line.
The electro-optical device according to claim 1 or 2. The control circuit controls the k selection signals so that a signal line to which an image signal is supplied in the first supply period differs between the two horizontal scanning periods;
The electro-optical device according to claim 1, wherein The control circuit controls the k selection signals so that a signal line to which an image signal is supplied in the first supply period differs in the k horizontal scanning periods;
The electro-optical device according to claim 1, wherein The control circuit controls the k selection signals so that a signal line to which an image signal is supplied in the last supply period is different in two horizontal scanning periods;
The electro-optical device according to claim 1, wherein The control circuit controls the k selection signals so that a signal line to which an image signal is supplied in the last supply period varies in the k horizontal scanning periods;
The electro-optical device according to claim 1, wherein The control circuit causes a precharge period overlapping the first supply period to precede the first supply period, leaving a period overlapping the first supply period, and overlapping the predetermined supply period. Controlling the k selection signals so that the period precedes the predetermined supply period, leaving a period overlapping the predetermined supply period;
The electro-optical device according to claim 1, wherein: The control circuit supplies a supply period for supplying an image signal to a first signal line of the k signal lines, and the first supply period in a first horizontal scan period that is one of the two horizontal scan periods. The k selection signals are assigned to the predetermined supply period in the second horizontal scanning period, which is the other of the two horizontal scanning periods, and the first supply period is longer than the predetermined supply period. Control
The precharge circuit does not supply a precharge signal to the first signal line during the first horizontal scanning period, and does not supply a precharge signal to the first signal line during the second horizontal scanning period. Supply,
The electro-optical device according to claim 1, wherein The end time of the supply period and the end time of the precharge period that overlap with the supply period are the same,
The electro-optical device according to claim 1, wherein The end time of the supply period is earlier than the end time of the precharge period overlapping with the supply period,
The electro-optical device according to claim 1, wherein   An electronic apparatus comprising the electro-optical device according to claim 1. A plurality of scan lines;
a plurality of signal lines each including k (k is an integer of 3 or more);
A reference line to which a reference potential is applied;
A pixel that is disposed corresponding to each intersection of the plurality of scanning lines and the plurality of signal lines, includes a storage capacitor connected to the reference line, and holds a potential corresponding to an image signal in the storage capacitor;
An image signal circuit for supplying an image signal to one of the k signal lines in each of the k supply periods included in the horizontal scanning period;
One of the k signal lines in each of the precharge periods corresponding to the 1st to (k-1) th supply periods of the k supply periods included in the horizontal scanning period. A precharge circuit for supplying a precharge signal to the signal line;
One of the first supply period and the kth supply period among the k supply periods included in the horizontal scanning period is defined as the first supply period of the k supply periods. A control circuit for controlling the k supply periods so as to be longer than other supply periods excluding the period and the kth supply period;
An electro-optical device comprising: A plurality of scan lines;
a plurality of signal lines each including k (k is an integer of 3 or more);
A reference line to which a reference potential is applied;
A pixel that is disposed corresponding to each intersection of the plurality of scanning lines and the plurality of signal lines, includes a storage capacitor connected to the reference line, and holds a potential corresponding to an image signal in the storage capacitor;
An image signal circuit for supplying an image signal to one of the k signal lines in each of the k supply periods included in the horizontal scanning period;
Among the k supply periods included in the horizontal scanning period, h precharges corresponding to the first to (k-1) th supply periods (h is an integer not less than 2 and not more than k-1). A precharge circuit for supplying a precharge signal to one of the k signal lines in each of the periods;
Of the k supply periods included in the horizontal scanning period, the k supply periods corresponding to the first precharge period are longer than the supply periods corresponding to the second precharge period. A control circuit for controlling the supply period of
An electro-optical device comprising: Corresponding to each intersection of a plurality of scanning lines, k (k is an integer of 3 or more) signal lines, a reference line to which a reference potential is applied, and the plurality of scanning lines and the k signal lines A pixel that is arranged and includes a storage capacitor connected to the reference line, and stores a potential corresponding to an image signal in the storage capacitor; and k signal lines that sequentially select the k signal lines in a horizontal scanning period. An image signal circuit for sequentially supplying image signals to the k signal lines during the k supply periods based on the selection signal, and the image signal circuit among the k signal lines during the horizontal scanning period. A driving method of an electro-optical device comprising a precharge circuit for supplying a precharge signal in a predetermined order to a signal line before supplying an image signal,
In the horizontal scanning period, at least one of the first supply period and the last supply period among the k supply periods for sequentially supplying the image signals to the k signal lines is set to the k supply lines. Controlling the k selection signals to be longer than a predetermined supply period excluding the first supply period and the last supply period.
A driving method for an electro-optical device.

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