JP6277590B2 - Display control circuit, electro-optical device, and electronic apparatus - Google Patents

Description

  The present invention relates to a display control circuit, an electro-optical device, an electronic apparatus, and a control method for the electro-optical device.

A liquid crystal display device is known as an example of an electro-optical device including an electro-optical element whose optical characteristics change with electric energy. The liquid crystal display device includes a plurality of data lines and a plurality of scanning lines, and a pixel circuit is provided corresponding to the intersection of the data lines and the scanning lines. The pixel circuit includes a selection transistor and a liquid crystal element as an electro-optical element. The selection transistor is controlled to be turned on and off in accordance with a scanning signal supplied through the scanning line. When the selection transistor is turned on, an image signal supplied via the data line is applied to the liquid crystal element, and when the selection transistor is turned off, the voltage of the image signal is held in the liquid crystal element. That is, the voltage of the first written image signal is held in the liquid crystal element from the time the image signal is written to the pixel circuit until the next image signal is written, and the liquid crystal element has a transmittance corresponding to the voltage of the image signal. Be controlled. In driving the electro-optical device, a plurality of scanning lines are sequentially selected, and an image signal is written to the pixel circuit corresponding to the selected scanning line via the data line. For this reason, the voltage of the data line changes every horizontal scanning period.
By the way, the data line and the liquid crystal element are capacitively coupled by stray capacitance. For this reason, if the voltage of the data line fluctuates in the period from writing an image signal to a pixel circuit corresponding to a certain scanning line until writing the next image signal, the image signal held in the liquid crystal element by capacitive coupling The voltage will fluctuate. As a result, the quality of the display image is degraded. In particular, the liquid crystal display device employs polarity inversion driving that inverts the polarity of an image signal at a predetermined period (for example, one field) around a reference level. For this reason, the voltage of the data line greatly fluctuates and a phenomenon called so-called vertical crosstalk may occur.
Therefore, in order to improve vertical crosstalk, image data for one field is stored in a large-capacity memory, and so-called vertical crosstalk correction that corrects vertical crosstalk based on the image data for one field accumulated in the memory. The technique regarding is known (for example, patent document 1 and 2).
Further, in the liquid crystal display device that displays the same image in the first field and the second field, two small-capacity memories are used, vertical crosstalk correction is not performed for the first field, and vertical crossing is performed only for the second field. A technique for correcting the talk is known (for example, Patent Document 3).

JP 2003-330093 A Japanese Patent No. 3869464 Japanese Patent No. 4816031

However, the techniques of Patent Documents 1 and 2 have a problem that a large-capacity memory is required, which increases the circuit scale and decreases the yield and reliability.
Further, since the technique described in Patent Document 3 does not execute vertical crosstalk correction in the first field, the correction amount in the vertical crosstalk correction executed in the second field is set to both the first field and the second field. This is larger than the correction amount when vertical crosstalk correction is performed. As a result, there is a problem that flicker due to a luminance difference between the first field and the second field occurs in a pixel that is subject to vertical crosstalk correction, and display quality is deteriorated.

  The present invention has been made in view of the above-described circumstances, and it is an object of the present invention to suppress vertical crosstalk while minimizing display quality degradation without requiring a large-capacity frame memory.

  In order to solve the above problems, a control method of an electro-optical device according to the present invention is a control method of an electro-optical device including a data line and a pixel circuit provided corresponding to the data line. In the first unit period of the display period, the electro-optical device is controlled so that the pixel corresponding to the pixel circuit displays black, and the second of the display period following the first unit period. In the unit period, based on input image data supplied from the start of the display period to the present, the current input image data is corrected to generate image data, and the image signal is generated based on the image data. Then, the generated image signal is supplied to the pixel circuit via the data line.

According to the present invention, even when there is a high possibility of occurrence of vertical crosstalk such as polarity inversion driving, the second unit period is based on the input image data supplied from the start of the display period to the present. Therefore, the occurrence of vertical crosstalk can be suppressed. Further, in the present invention, since the screen is displayed in black in the first unit period, the occurrence of a situation in which a luminance difference between the first unit period and the second unit period occurs in some pixels is suppressed. As a result, the occurrence of flicker can be suppressed. Further, in the present invention, since the correction only needs to be performed in the second unit period, the circuit scale and the manufacturing cost are reduced as compared with the case where the correction is performed in both the first unit period and the second unit period. be able to.
In the present invention, “black display” may mean that a light source (backlight) is turned off, or an image signal designating a gradation corresponding to black display is supplied to a pixel. It may be.

  In the control method of the electro-optical device described above, the first unit period, the second unit period, a third unit period following the second unit period, and the third unit period are continued. Including a fourth unit period, based on the input image data supplied from the start of the display period to the present in the third unit period and the fourth unit period of the display period, Correcting the current input image data to generate image data, generating the image signal based on the image data, and supplying the generated image signal to the pixel circuit via the data line; It may be characterized by.

  The display control circuit according to the present invention is provided in an electro-optical device including a data line, a pixel circuit provided corresponding to the data line, and a light source, and the pixel circuit is provided via the data line. A display control circuit that supplies an image signal to the light source and controls the operation of the light source, wherein the light source is turned off in the first unit period of the display period, and the first unit period of the display period A light source control unit that controls the operation of the light source so as to turn on the light source in a second unit period, and an input supplied from the start of the display period to the present in the second unit period. An integration unit that generates integration data corresponding to an integration value obtained by integrating the voltage of the image signal supplied to the data line from the past to the present for one unit period based on the image data; and the second unit In a period, based on the integrated data, a correction unit that corrects the current input image data to generate image data, and generates the image signal based on the image data. And a drive unit that supplies the pixel circuit via a data line.

According to the present invention, even when there is a high possibility of occurrence of vertical crosstalk such as polarity inversion driving, in the second unit period, the current value is based on integration data that is an integration value for one unit period of the image signal. Therefore, the occurrence of vertical crosstalk can be suppressed.
In the present invention, since the light source is turned off in the first unit period, deterioration of the light source and deterioration of the pixel circuit and the like can be suppressed, and the life of the electro-optical device can be extended. In addition, since the light source is turned off in the first unit period, occurrence of a situation in which a luminance difference between the first unit period and the second unit period occurs in some pixels can be suppressed, and as a result. Generation of flicker can be suppressed.
Further, in the present invention, since the correction only needs to be performed in the second unit period, the circuit scale and the manufacturing cost are reduced as compared with the case where the correction is performed in both the first unit period and the second unit period. be able to.

  In the display control circuit described above, the display period includes the first unit period, the second unit period, a third unit period following the second unit period, and the third unit period. And the light source control unit is configured to maintain the light source in an on state during a period from the start of the second unit period to the end of the fourth unit period. The operation of the light source is controlled, and the integration unit is configured to perform the data operation based on input image data supplied from the start of the display period to the present in the third unit period and the fourth unit period. Generating integrated data corresponding to an integrated value obtained by integrating the voltage of the image signal supplied to the line from the past to the present by one unit period, and the correction unit includes the third unit period and the fourth unit period. In the unit period, Based on the data, to generate image data by correcting the input image data of the current may be characterized in that.

  In the display control circuit described above, the correction unit generates image data based on the current input image data in the first unit period, and the driving unit performs reference at a predetermined cycle in the display period. The image signal is generated so that the polarity of the signal is inverted around the level, and the integration unit performs one of addition and subtraction of the input image data according to the polarity of the image signal in the display period. Thus, the integrated image data may be generated by integrating the input image data from the start of the display period to the present.

According to this aspect, since polarity inversion driving that inverts the polarity of the signal at a predetermined period is employed, occurrence of burn-in or the like can be prevented.
Further, when polarity inversion driving is adopted, there is a high possibility that vertical crosstalk will occur. However, in the second unit period, the current image data is based on integrated data that is an integrated value for one unit period of the image signal. Therefore, the occurrence of vertical crosstalk can be suppressed.

  In the display control circuit described above, the predetermined period is a period of the unit period, and the integration unit includes a storage unit that stores the integration data, and current input image data in the first unit period. And the data read from the storage unit are added to the storage unit to update the storage content of the storage unit, and the end of the first unit period of the display period In a later period, the storage content of the storage unit is updated by writing new integration data calculated based on the integration data read from the storage unit and the current input image data to the storage unit, A calculation unit that initializes the storage contents of the storage unit at the end of the display period, and the driving unit inverts the polarity of the image signal for each unit period It may be characterized in.

  Further, in the display control circuit described above, the driving unit includes a polarity of the image signal in a first unit period of one display period, and a first unit period of another display period following the one display period. The image signal may be generated so that the polarity of the image signal is opposite.

  In the above-described display control circuit, the first unit period includes a first partial period and a second partial period, and the driving unit transmits the image signal to the data line in the first partial period. And supplying a predetermined precharge potential to the data line in the second partial period.

In the display control circuit described above, when the second unit period starts, the light source control unit increases the luminance of the light source beyond a predetermined luminance, and starts the predetermined period from the start of the second unit period. When time elapses, the light source may be turned on so that the luminance of the light source converges to the predetermined luminance.
According to this aspect, even when the light source is turned off in the first unit period, the luminance of the light source exceeds the predetermined luminance before the predetermined time elapses from the start of the second unit period. The average value of the luminance of the light source in the entire display period can be brought close to the average value of the luminance when the light source is turned on in both the first unit period and the second unit period, and the screen becomes dark. Can be prevented.

  In addition, a display control circuit according to the present invention is provided in a display device including a data line and a pixel circuit provided corresponding to the data line, and outputs an image signal to the pixel circuit via the data line. A display control circuit for supplying, in a second unit period following the first unit period in the display period, based on input image data supplied from the start of the display period to the present time. An integration unit that generates integration data obtained by integrating the input image data from the start to the present, and image data corresponding to the image signal in which the pixels corresponding to the pixel circuit display black in the first unit period. A correction unit that generates and generates image data by correcting the current input image data based on the accumulated data in the second unit period, and based on the image data Generating an image signal, the generated image signal, and a driver for supplying to the pixel circuit through the data line, characterized in that.

  In the display control circuit described above, the display period includes the first unit period, the second unit period, a third unit period following the second unit period, and the third unit period. And the integration unit is configured to, based on input image data supplied from the start of the display period to the present in the third unit period and the fourth unit period. Generating integrated data corresponding to an integrated value obtained by integrating the voltage of the image signal supplied to the data line from past to present for one unit period, and the correction unit includes the third unit period, and In the fourth unit period, image data may be generated by correcting the current input image data based on the integrated data.

  An electro-optical device according to the present invention is an electro-optical device including the display control circuit described above, a data line, a pixel circuit provided corresponding to the data line, and a light source, and the pixel. The circuit includes a liquid crystal element, and the light source emits light with a predetermined luminance in an ON state, and a time at which the luminance of the light source becomes the predetermined luminance in the second unit period corresponds to the pixel circuit. The pixel transmittance is earlier than the time when the transmittance corresponding to the image signal is reached.

  The electro-optical device according to the present invention includes a data line, a pixel circuit provided corresponding to the data line, and a pixel corresponding to the pixel circuit in the first unit period of the display period. Controlling the electro-optical device so that, in a second unit period following the first unit period in the display period, based on input image data supplied from the start of the display period to the present, A display control circuit that corrects current input image data to generate image data, generates the image signal based on the image data, and supplies the generated image signal to the pixel circuit via the data line And comprising.

  According to another aspect of the invention, an electronic apparatus includes the electro-optical device including any one of the display control circuits described above, or the electro-optical device including any one of the above-described display control circuits. Examples of such electronic devices include a car navigation device, a personal computer, a television, a projection display device, and a mobile phone.

1 is a block diagram of an electro-optical device according to a first embodiment of the invention. FIG. It is a circuit diagram of a pixel circuit. It is a block diagram which shows the structure of a signal generation circuit. 6 is a timing chart for explaining the operation of the signal generation circuit. It is explanatory drawing for demonstrating the integration data memorize | stored in a memory | storage part. It is explanatory drawing for demonstrating the process which updates integration data. It is explanatory drawing for demonstrating vertical crosstalk correction | amendment. 6 is a timing chart for explaining the operation of the signal generation circuit according to Comparative Example 1; It is explanatory drawing for demonstrating vertical crosstalk correction | amendment. It is a timing chart for demonstrating operation | movement of the signal generation circuit which concerns on 2nd Embodiment of this invention. It is a timing chart for demonstrating operation | movement of a light source and a liquid crystal. 6 is a timing chart for explaining operations of a light source and a liquid crystal according to Comparative Example 2; 10 is a timing chart for explaining the operation of the signal generation circuit according to Modification 1; 10 is a timing chart for explaining the operation of a signal generation circuit according to Modification 3. 10 is a timing chart for explaining the operation of a signal generation circuit according to Modification 3. 6 is a timing chart for explaining operations of a light source and a liquid crystal according to Comparative Example 4; It is a perspective view of an electronic device (projection type display device). It is a perspective view of an electronic device (personal computer). It is a perspective view of an electronic device (cellular phone).

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. However, in each figure, the size and scale of each part are appropriately changed from the actual ones. Further, since the embodiments described below are preferable specific examples of the present invention, various technically preferable limitations are attached thereto. However, the scope of the present invention is particularly limited in the following description. Unless otherwise stated, the present invention is not limited to these forms.

<A. First Embodiment>
FIG. 1 is a block diagram of an electro-optical device 1 according to the first embodiment of the present invention. The electro-optical device 1 includes an electro-optical panel 10 and a signal generation circuit 20. The electro-optical panel 10 includes a display unit 30 in which a plurality of pixel circuits PX are arranged, a drive circuit 40 that drives each pixel circuit PX, and a light source 12. The signal generation circuit 20 and the drive circuit 40 are collectively referred to as a display control circuit 50.

  The display unit 30 is formed with M scanning lines 32 extending in the x direction and N data lines 34 extending in the y direction intersecting the x direction (M and N are natural numbers). The plurality of pixel circuits PX are arranged in a matrix of vertical M rows × horizontal N columns corresponding to each intersection of the scanning lines 32 and the data lines 34 in the display unit 30. In the present embodiment, the pixel circuit PX is arranged at all of the M × N intersections formed by the M scanning lines 32 and the N data lines 34, but one of these M × N intersections. You may arrange | position to a part.

The drive circuit 40 is a circuit that supplies an image signal VD [n] for controlling the display gradation of the pixel corresponding to each pixel circuit PX to each pixel circuit PX, and includes a scanning line drive circuit 42, a data line drive circuit 44, and the like. It comprises.
The scanning line driving circuit 42 sequentially selects the scanning lines 32 by supplying the scanning signals Y [1] to Y [M] corresponding to the scanning lines 32. The scanning signal Y [m] (m = 1 to M) is set to a predetermined selection potential (that is, the mth scanning line 32 is selected), whereby the mth scanning line 32 is selected.
The data line driving circuit 44 supplies the image signals VD [1] to VD [N] to each of the N data lines 34 in synchronization with the selection of the scanning line 32 by the scanning line driving circuit 42. The image signal VD [n] (n = 1 to N) is variably set according to the display gradation specified by the input image data Din, which will be described later, for the pixel corresponding to each pixel circuit PX.
In the present embodiment, in order to prevent so-called burn-in, polarity inversion driving is employed in which the polarity of a voltage applied to the liquid crystal element 60 described later is inverted at a predetermined period. In this example, the signal level of the image signal VD [n] is inverted every unit period around a predetermined reference potential Vref.
Here, the unit period is a period that is one unit of an operation for driving the pixel circuit PX. In this embodiment, the unit period is a vertical scanning period. However, the unit period can be arbitrarily set, and may be a natural number times the vertical scanning period, for example.

  The light source 12 is configured using, for example, an LED (Light Emitting Diode). The light source 12 is provided at a position overlapping the display unit 30 when the electro-optical panel 10 is viewed in plan from the observation side. In FIG. 1, for convenience of description, it is shown below the display unit 30 in the drawing.

  FIG. 2 is a circuit diagram of each pixel circuit PX. As shown in FIG. 2, each pixel circuit PX includes a liquid crystal element 60 and a selection switch SW. The liquid crystal element 60 is an electro-optical element composed of a pixel electrode 62 and a common electrode 64 facing each other and a liquid crystal 66 between both electrodes. The transmittance (display gradation) of the liquid crystal 66 changes according to the voltage applied between the pixel electrode 62 and the common electrode 64. A configuration in which an auxiliary capacitor is connected in parallel to the liquid crystal element 60 may also be employed. The selection switch SW is composed of, for example, an N-channel type transistor whose gate is connected to the scanning line 32, and is provided between the liquid crystal element 60 and the data line 34 to provide electrical connection (conduction / insulation) between them. Control. By setting the scanning signal Y [m] to the selection potential, the selection switches SW in the pixel circuits PX in the m-th row are simultaneously turned on.

  When the scanning line 32 corresponding to the pixel circuit PX is selected and the selection switch SW of the pixel circuit PX is controlled to be in the ON state, the liquid crystal element 60 of the pixel circuit PX has the data line 34 to the pixel circuit PX. A voltage corresponding to the supplied image signal VD [n] is applied, and the liquid crystal 66 of the pixel circuit PX is set to a transmittance corresponding to the image signal VD [n]. Further, when the light source 12 is turned on (lighted) and light is emitted from the light source 12, the light passes through the liquid crystal 66 of the liquid crystal element 60 included in the pixel circuit PX and travels to the viewer side. That is, when a voltage corresponding to the image signal VD [n] is applied to the liquid crystal element 60 and the light source 12 is turned on, the pixel corresponding to the pixel circuit PX corresponds to the image signal VD [n]. The displayed gradation is displayed.

After the voltage corresponding to the image signal VD [n] is applied to the liquid crystal element 60 of the pixel circuit PX, when the selection switch SW is turned off, an applied voltage corresponding to the image signal VD [n] is ideally applied. Retained. Therefore, ideally, each pixel displays a gradation corresponding to the image signal VD [n] in a period from when the selection switch SW is turned on to when it is next turned on.
However, actually, as shown in FIG. 2, there is no gap between the data line 34 and the pixel electrode 62 (or between the data line 34 and the wiring that electrically connects the pixel electrode 62 and the selection switch SW). , Parasitic capacitance Ca. For this reason, while the selection switch SW is in the OFF state, the potential fluctuation of the data line 34 propagates to the pixel electrode 62 through the capacitor Ca, and the applied voltage of the liquid crystal element 60 may fluctuate. In this case, the pixel cannot accurately display the gradation corresponding to the image signal VD [n].

Returning to FIG.
As shown in FIG. 1, input image data Din is supplied to the signal generation circuit 20 from a host device (not shown) in synchronization with a synchronization signal.
Here, the input image data Din is data defining the gradation to be displayed by the pixel corresponding to each pixel circuit PX. For example, the input image data Din is digital data that defines the gradation to be displayed in each pixel by 8 bits. Hereinafter, among the input image data Din, the input image data Din that designates the gradation for the M pixel circuits PX located in the n-th column is referred to as input image data Din [n], and The input image data Din that designates the gradation for one pixel circuit PX located in the mth row and the nth column may be referred to as input image data Din [m] [n].
The synchronization signal is a signal including a vertical synchronization signal, a horizontal synchronization signal, and a dot clock signal, for example.

The signal generation circuit 20 generates a control signal Ctr that is a signal for controlling the operation of the electro-optical panel 10 based on the synchronization signal supplied from the host device, and supplies the generated control signal Ctr to the drive circuit 40. To do. Here, the control signal Ctr is a signal including, for example, a pulse signal, a clock signal, an enable signal, and the like. The control signal Ctr may include a polarity signal P described later.
Further, the signal generation circuit 20 generates image data Dx based on the input image data Din and supplies it to the data line driving circuit 44. In the present embodiment, the image data Dx is a digital signal, but may be an analog signal. In the following, among the image data Dx, the image data Dx generated based on the input image data Din [n] is referred to as image data Dx [n], and the input image data Din [m] [n] The image data Dx generated based on this may be referred to as image data Dx [m] [n].
In addition, the signal generation circuit 20 generates a light source control signal Lc for controlling the operation of the light source 12 based on a signal generated based on the synchronization signal, and supplies this to the light source 12.

FIG. 3 is a functional block diagram showing the configuration of the signal generation circuit 20. As shown in this figure, the signal generation circuit 20 includes a control unit 21, a light source control unit 22, an integration unit 23, and a correction unit 26.
The control unit 21 generates a control signal Ctr based on the synchronization signal supplied from the host device, supplies the control signal Ctr to the drive circuit 40, and reset signal RES based on the generated control signal Ctr or the synchronization signal. Is generated. The reset signal RES is a signal for initializing the contents stored in the storage unit 25 described later. Further, the control unit 21 generates a polarity signal P that is a signal representing the polarity of the image signal VD [n] based on the control signal Ctr or the synchronization signal.
The light source control unit 22 generates a light source control signal Lc based on the polarity signal P (or control signal Ctr) generated by the control unit 21 and supplies this to the light source 12.

  The integrating unit 23 generates integrated data DS [1] to DS [N] corresponding to each of the N data lines 34. The integrated data DS [n] (n = 1 to N) is used when vertical crosstalk correction is performed on the input image data Din [n] corresponding to the pixel circuit PX in the nth column of the input image data Din. Data used. The input image data Din [n] is composed of input image data Din [1] [n] to Din [M] [n]. Therefore, in the following, among the integration data DS [n], the integration data DS [n] corresponding to the input image data Din [m] [n] may be expressed as integration data DS [m] [n].

The integration unit 23 includes a storage unit 25 that stores integration data DS [1] to DS [N], and a calculation unit 24.
The computing unit 24 updates the accumulated data DS [n] stored in the storage unit 25 based on the input image data Din [n] and the polarity signal P supplied from the control unit 21, and the updated accumulated data. Data DS [n] is output. In addition, the calculation unit 24 initializes the storage contents of the storage unit 25 based on the reset signal RES supplied from the control unit 21.
Details of the update and initialization of the integration data DS [n] executed in the integration unit 23 will be described later.

When the polarity of the image signal VD [n] indicated by the polarity signal P is negative, the correction unit 26 corrects the vertical crosstalk with respect to the input image data Din [n] based on the integrated data DS [n]. To generate image data Dx [n]. More specifically, when the polarity indicated by the polarity signal P is negative, the correction unit 26 applies the input image data Din [m] [n] based on the integrated data DS [m] [n]. Image data Dx [m] [n] is generated by performing vertical crosstalk correction.
On the other hand, when the polarity indicated by the polarity signal P is positive, the correction unit 26 generates image data Dx [n] based on the input image data Din [n] without performing vertical crosstalk correction. .

FIG. 4 is a timing chart showing the operation of the signal generation circuit 20.
As shown in the figure, the operation period of the electro-optical device 1 includes a plurality of display periods F. Each display period F includes a unit length P1 having a predetermined length (an example of “first unit period”) and a unit period P2 having a predetermined length following the unit period P1 (an example of “second unit period”). It is divided.

Further, as described above, the data line driving circuit 44 generates the image signal VD [n] in which the signal level is inverted around a predetermined reference potential Vref for each unit period based on the image data Dx [n]. . More specifically, the data line driving circuit 44 generates a positive-polarity image signal VD [n] having a voltage higher than the predetermined reference potential Vref in the unit period P1, and in the unit period P2, A negative-polarity image signal VD [n] that is a low voltage with respect to the reference potential Vref is generated.
The polarity signal P generated by the control unit 21 represents the polarity of such an image signal VD [n]. That is, when the polarity signal P is high level, the image signal VD [n] has a positive polarity, and when the polarity signal P is low level, the image signal VD [n] has a negative polarity.

  The reset signal RES is the timing at which the display period F starts, that is, the unit period P2 of one display period F ends, and the unit period P1 of another display period F subsequent to the one display period F starts. It is a signal that becomes high level at the timing. When the value indicated by the reset signal RES supplied from the control unit 21 becomes a high level, the calculation unit 24 initializes the contents of the integration data DS [1] to DS [N] stored in the storage unit 25.

As illustrated in FIG. 4, the correction unit 26 does not perform vertical crosstalk correction in the unit period P1 (that is, when the polarity indicated by the polarity signal P is positive), and does not perform the vertical crosstalk correction. Based on the above, image data Dx [n] is generated. More specifically, the correction unit 26 may use the input image data Din [n] as it is as the image data Dx [n] in the unit period P1, or a lookup table (illustrated) showing the VT characteristics of the electro-optical panel 10. The image data Dx [n] may be generated by performing gamma correction on the input image data Din [n] with reference to (omitted).
On the other hand, in the unit period P2 (that is, when the polarity indicated by the polarity signal P is negative), the correction unit 26 uses the integrated data DS [n] to perform vertical crosstalk with respect to the input image data Din [n]. Image data Dx [n] is generated by performing the correction. For example, in the unit period P2, the correction unit 26 adds the value “k * DS [n]” obtained by multiplying the value indicated by the integrated data DS [n] by the negative coefficient k and the input image data Din [n]. Thus, the image data Dx [n] may be generated, or the image data Dx [n] may be generated by further performing gamma correction on the added value.
Details of the integrated data DS will be described later.

  As shown in FIG. 4, the light source control signal Lc indicates a value LcL for controlling the light source 12 to the off state when the polarity indicated by the polarity signal P is positive, and when the polarity is negative, A value LcH for controlling 12 to the ON state is shown.

  Thus, the signal generation circuit 20 generates the image data Dx without turning off the light source 12 and performing the vertical crosstalk correction on the input image data Din in the unit period P1. Further, in the unit period P2, the signal generation circuit 20 turns on the light source 12 and generates image data Dx by performing vertical crosstalk correction on the input image data Din.

Hereinafter, update (generation) and initialization of the integration data DS [n] executed in the integration unit 23 will be described with reference to FIGS. 5 and 6.
FIG. 5 is an explanatory diagram showing an example of the contents of the integrated data DS [n] stored in the storage unit 25. FIG. 6 is an explanatory diagram for explaining the update of the integrated data DS [n] executed by the calculation unit 24. In these drawings, it is assumed that M = 6, that is, a case where six (six rows) pixel circuits PX are provided corresponding to each data line 34.

As shown in FIG. 5, when the reset signal RES is supplied at the timing when the display period F is started, the calculation unit 24 initializes the storage contents of the storage unit 25.
In the present embodiment, the initialization is a process of setting a predetermined initial value, for example, “0” to the value of the integrated data DS [n] stored in the storage unit 25. However, the initialization may be, for example, a process of erasing the storage content of the storage unit 25 (or setting a Null value).

When the display period F is started, the calculation unit 24 adds or subtracts the input image data Din [n] with respect to the integration data DS [n] stored in the storage unit 25, whereby the integration data DS [n] ] Is updated. Whether the calculation unit 24 performs the addition or the subtraction is determined based on the polarity indicated by the polarity signal P.
Hereinafter, details of the process of updating (generating) the integrated data DS [n] performed by the calculation unit 24 will be described.

As shown in FIG. 5, the arithmetic unit 24 adds the input image data Din [n] to the integrated data DS [n] stored in the storage unit 25 in the unit period P1 in which the polarity signal P is positive. As a result, the integrated data DS [n] is updated.
Specifically, the calculation unit 24 first sets an initial value “0” to the integrated data DS [n] stored in the storage unit 25 at the timing when the unit period P1 is started.
Next, when the input image data Din [1] [n], which is the input image data Din [n] supplied first in the unit period P1, is supplied to the calculation unit 24, the input image data Din [1] [ n] is added to the value “0” of the accumulated data DS [n] stored in the storage unit 25, and the added value “d11” is added to the storage unit 25 as the accumulated data DS [n]. The accumulated data DS [n] is updated by storing them.
Next, when the input image data Din [2] [n] is supplied, the arithmetic unit 24 receives the value “d12” indicated by the input image data Din [2] [n] and the integrated data stored in the storage unit 25. The accumulated data DS [n] is updated by adding the value “d11” of DS [n] and storing the added value “d11 + d12” in the storage unit 25 as accumulated data DS [n]. Thereafter, the calculation unit 24 repeats the same process until the unit period P1 ends.

Thus, when the unit period P1 ends, the storage unit 25 stores the integrated value S0 obtained by integrating the input image data Din [n] from the past to the present for one unit period, as shown in FIG. (= D11 + d12 + d13 + d14 + d15 + d16), that is, the total value of the values “d11” to “d16” indicated by the input image data Din [1] [n] to Din [6] [n] It is stored as integrated data DS [n]. In other words, the integration data DS [n] stored in the storage unit 25 when the unit period P1 ends corresponds to an integration value obtained by integrating the image signal VD [n] from the past to the present for one unit period. .
As described above, in the unit period P1, the correction unit 26 does not execute the vertical crosstalk correction using the integrated data DS [n] updated by the calculation unit 24. For this reason, the correction unit 26 discards the integrated data DS [n] supplied from the calculation unit 24.

As shown in FIG. 5, in the unit period P2 in which the polarity signal P has a negative polarity, the calculation unit 24 calculates the value indicated by the input image data Din [n] from the integrated data DS [n] stored in the storage unit 25. The accumulated data DS [n] is updated by subtracting the multiplied value.
Specifically, when the unit period P2 is started and the input image data Din [1] [n], which is the first input image data Din [n] supplied in the unit period P2, is supplied to the calculation unit 24. Then, the value “d11 + d12 + d13 + d14 + d15 + d16” of the integrated data DS [n] stored in the storage unit 25 is obtained by doubling the value “d21” indicated by the input image data Din [1] [n]. ”And the subtraction value“ d11 + d12 + d13 + d14 + d15 + d16−2 * d21 ”is stored in the storage unit 25 as new integration data DS [1] [n], so that the integration data DS [ Update n].
Next, when the input image data Din [2] [n] is supplied, the arithmetic unit 24 stores a value obtained by doubling the value “d22” indicated by the input image data Din [2] [n], in the storage unit 25. Is subtracted from the accumulated data DS [n] value “d11 + d12 + d13 + d14 + d15 + d16-2 * d21” stored in the memory and the subtraction value “d11 + d12 + d13 + d14 + d15 + d16−2 *” The accumulated data DS [n] is updated by storing “d21-2 * d22” in the storage unit 25 as new accumulated data DS [2] [n].
Thereafter, the calculation unit 24 repeats the same process until the unit period P2 ends. Then, the calculation unit 24 sets an initial value “0” to the integrated data DS [n] stored in the storage unit 25 at the timing when the unit period P2 ends or at the timing after the unit period P2 ends.

When the image displayed on the display unit 30 is a still image, the display gradation specified in the unit period P1 and the display gradation specified in the unit period P2 for a pixel having the input image data Din are equal.
Further, even when the image displayed on the display unit 30 is a moving image and the display gradation of each pixel changes with the movement of the image, the display gradation of each pixel in the unit period (or display period). In general, the change is sufficiently small so that it can be considered that there is no change in the display gradation. Therefore, even when the image displayed on the display unit 30 is a moving image, normally, the display gradation specified in the unit period P1 and the unit period P2 are specified for a certain pixel of the input image data Din. It can be considered that the display gradation is equal.

Thus, the value “d11” indicated by the input image data Din [1] [n] in the unit period P1 is equal to the value “d21” indicated by the input image data Din [1] [n] in the unit period P2. Can be seen.
Therefore, as shown in FIGS. 6A and 6B, the value “d11 + d12 + d13 + d14 + d15 +” indicated by the integrated data DS [n] stored in the storage unit 25 at the start of the unit period P2. The value obtained by subtracting the value “d21” indicated by the input image data Din [1] [n] from “d16 (= integrated value S0)” is considered to be equal to the value “d12 + d13 + d14 + d15 + d16”. Can do. The value obtained by subtracting the value “d21” from the value “d12 + d13 + d14 + d15 + d16” is the integral value S1 = “d12 + d13 + d14 + d15 + d16−d21” shown in FIG. Can be regarded as equal. That is, the integrated value S1 and the integrated data DS [1] [n] can be regarded as being equal as shown in the following formula (1).
DS [1] [n] ≒ S1 (= d12 + d13 + d14 + d15 + d16-d21) ...... Equation (1)

Similarly, as shown in FIG. 6 or the following formulas (2) to (6), integrated data DS [2] [n] to DS [6] [n] generated by the calculation unit 24 in the unit period P2 Can be considered to be equal to the integral values S2 to S6.
DS [2] [n] ≒ S2 (= d13 + d14 + d15 + d16-d21-d22) ...... Equation (2)
DS [3] [n] ≒ S3 (= d14 + d15 + d16-d21-d22-d23) ...... Equation (3)
DS [4] [n] ≒ S4 (= d15 + d16-d21-d22-d23-d24) ...... Equation (4)
DS [5] [n] ≒ S5 (= d16-d21-d22-d23-d24-d25) ...... Equation (5)
DS [6] [n] ≒ S6 (= -d21-d22-d23-d24-d25-d26) ...... Equation (6)

  As described above, the value indicated by the integrated data DS [n] generated by the calculation unit 24 in the unit period P2 is equal to the integrated value obtained by integrating the input image data Din [n] from the past to the present for one unit period. It can be regarded as being. In other words, the integration data DS [n] generated by the calculation unit 24 in the unit period P2 corresponds to an integration value obtained by integrating the image signal VD [n] from the past to the present for one unit period.

As described above, the electro-optical device 1 according to this embodiment performs vertical crosstalk correction. The effect of performing the vertical crosstalk correction will be described with reference to FIG. In FIG. 7, it is assumed that the electro-optical device 1 is in a normally black mode in which the pixels display black when no voltage is applied to the liquid crystal element 60.
When an image representing a white window Ar2 in a gray background Ar1 as shown in FIG. 7A is displayed on the display unit 30 of the electro-optical device 1 without performing vertical crosstalk correction, FIG. Vertical crosstalk as shown in FIG.

More specifically, as shown in FIG. 7B, a lighter color is displayed in the upper region Ar1a of the window Ar2 as compared to gray that should be originally displayed. This is because when the image signal VD2 is supplied to the pixel circuit located in the window Ar2, the image signal VD1a held by the pixel circuit located in the upper region Ar1a has the same polarity as the image signal VD2. to cause.
Further, as shown in FIG. 7B, a darker color is displayed in the lower area Ar1b of the window Ar2 as compared to the gray that should be displayed. This is because when the image signal VD2 is supplied to the pixel circuit located in the window Ar2, the image signal VD1b held by the pixel circuit located in the lower region Ar1b has a polarity opposite to that of the image signal VD2. to cause.

On the other hand, in this embodiment, vertical crosstalk correction is performed.
Specifically, in the electro-optical device 1 according to the present embodiment, by adding a value obtained by multiplying the value indicated by the integrated data DS [n] by a negative coefficient k from the input image data Din [n], an image is obtained. Data Dx [n] is generated, and an image signal VD [n] generated based on the image data Dx [n] is supplied to each pixel circuit PX.
As is clear from FIG. 6, integrated data DS [n] (for example, integrated data DS [1] [n]) corresponding to the pixel circuit PX located at the top of the display unit 30 is displayed at the bottom of the display unit 30. The positive value is larger than the integrated data DS [n] (for example, integrated data DS [6] [n]) corresponding to the pixel circuit PX located.
Therefore, for example, in the example shown in FIG. 7, the pixel circuit located in the upper region Ar1a is supplied with the image signal VD1a that displays a darker color than gray that should be displayed, and is located in the lower region Ar1b. The pixel circuit is supplied with an image signal VD1a that displays a lighter color than gray to be originally displayed. As a result, it is possible to suppress the occurrence of vertical crosstalk as shown in FIG. 7B, and to display an image that should be displayed as shown in FIG. 7A.

  In addition, as shown in FIG. 4, the signal generation circuit 20 according to the present embodiment turns off the light source 12 in the unit period P1, turns on the light source 12 in the unit period P2, and performs vertical crosstalk correction. The operation of the optical device 1 is controlled. The effect of performing such control will be described with reference to FIGS.

FIG. 8 is a timing chart showing the operation of the electro-optical device according to the comparative example 1.
As shown in this figure, the electro-optical device according to the comparative example 1 maintains the light source in the on state in both the unit period P1 and the unit period P2. Further, the electro-optical device according to the comparative example 1 does not perform the vertical crosstalk correction in the unit period P1. The electro-optical device according to the comparative example 1 is more powerful than the electro-optical device 1 according to the present embodiment in the unit period P2 in order to suppress the vertical crosstalk generated in the unit period P1 from being visually recognized. N ”Perform vertical crosstalk correction. Here, “strong” vertical crosstalk correction means that the magnitude of the correction value used in the correction is large.

For example, when the vertical crosstalk correction to be performed on the input image data Din in the present embodiment is expressed by the following expression (7), the vertical crosstalk correction to be performed in the electro-optical device according to the contrast 1 is larger than 1. It can be expressed by the following formula (8) using the coefficient α.
Dx [n] = Din [n] + k * DS [n] (7)
Dx [n] = Din [n] + α * k * DS [n] (8)
That is, the absolute value | α * k * DS [n] | of the correction amount in the correction performed by the electro-optical device according to the proportional 1 in the unit period P2 is the same as that in the unit period P2. The absolute value of the correction amount in the correction to be performed is larger than | k * DS [n] |.

When displaying an image having a white window on a gray background as shown in FIG. 7A, in the electro-optical device according to the comparative example 1, as shown in FIG. 9A, in the upper region Ar1a, A color brighter than the original gray is displayed in the unit period P1, and a color darker than the original gray is displayed in the unit period P2. In the lower region Ar1b, a color darker than the original gray is displayed in the unit period P1, and a lighter color than the original gray is displayed in the unit period P2.
For this reason, in the electro-optical device according to the comparative example 1, flicker due to the gradation difference between the unit period P1 and the unit period P2 occurs in the upper region Ar1a and the lower region Ar1b.

On the other hand, also in the electro-optical device 1 according to the present embodiment, when attention is paid to a certain pixel, the gradation is changed between the unit period P1 and the unit period P2, similarly to the electro-optical device according to the comparative example 1. Change.
However, as shown in FIG. 9B, the electro-optical device 1 turns off the light source 12 for the entire surface of the display unit 30 in the unit period P1 and displays the entire screen displayed on the display unit 30 as black display. A gradation change between the unit period P1 and the unit period P2 also occurs in the entire screen. Therefore, unlike the case where a change in gradation occurs in a part of the screen, the change in gradation does not stand out, and the change in gradation does not appear as flicker. Therefore, in the present embodiment, it is possible to prevent the gradation difference between the unit period P1 and the unit period P2 from being visually recognized as flicker.
In addition, since the electro-optical device 1 according to the present embodiment turns off the light source 12 during a half of the display period F, the light source 12 is prevented from being deteriorated and the electro-optical panel 10 including the pixel circuit PX is deteriorated. The life of the electro-optical device 1 can be extended as compared with the comparative 1 in which the light source 12 is turned on in the entire display period F.

When the image displayed on the display unit 30 is a moving image, the display gradation specified by the input image data Din for a certain pixel in the unit period P1 and the input image data Din for the certain pixel are The display gradation specified in the unit period P2 may differ greatly. In this case, the value indicated by the integrated data DS [n] is different from the integrated value obtained by integrating the input image data Din [n] from the past to the present for one unit period. That is, in this case, even if vertical crosstalk correction is performed on the input image data Din using the integrated data DS [n], occurrence of vertical crosstalk cannot be effectively suppressed.
However, the electro-optical device 1 according to the present embodiment initializes the storage contents of the storage unit 25 at the start (or end) timing of the display period F. Therefore, the value indicated by the integrated data DS [n] is different from an integrated value obtained by integrating the input image data Din [n] from the past to the present for one unit period, that is, a value not suitable for vertical crosstalk correction. However, the integrated data DS [n] is discarded at the end of the display period F. Therefore, even if accurate vertical crosstalk correction cannot be performed in a certain display period F because the integrated data DS [n] is a value that is not suitable for correction, In the subsequent display period F, accurate vertical crosstalk correction can be executed based on the new integrated data DS [n]. In other words, it is possible to prevent the correction based on the inaccurate integrated data DS [n] from being continuously performed over a plurality of display periods F.

Incidentally, in the electro-optical device 1 according to the present embodiment, the vertical crosstalk correction is performed only in the unit period P2 by turning off the light source 12 in the unit period P1, but the unit period P1 and the unit period P2 are performed. A mode in which vertical crosstalk correction is executed in both cases is also assumed.
However, when the vertical crosstalk correction is executed in both the unit period P1 and the unit period P2, the calculation unit 24 for calculating and storing integrated data DS [n] used for the vertical crosstalk correction executed in the unit period P1. And two storage units 23 including a storage unit 25 and a calculation unit 24 and a storage unit 25 for calculating and storing integrated data DS [n] used for vertical crosstalk correction executed in the unit period P2. It will be necessary.
On the other hand, since the electro-optical device 1 according to the present embodiment performs the vertical crosstalk correction only in the unit period P2, the integrated data DS [n] used for the vertical crosstalk correction executed in the unit period P2 is used. Only one integrating unit 23 for calculating and storing is required, and the circuit scale and manufacturing cost can be reduced as compared with the case where the vertical crosstalk correction is executed in both the unit period P1 and the unit period P2.

<B. Second Embodiment>
The electro-optical device 1 according to the first embodiment is a so-called double speed drive in which the display period F is divided into two unit periods of a unit period P1 and a unit period P2.
In contrast, the electro-optical device according to the second embodiment is different from the electro-optical device 1 according to the first embodiment in that the display period F is a so-called quadruple speed drive in which the display period F is divided into four unit periods. To do. Hereinafter, the electro-optical device according to the second embodiment will be described with reference to FIG.

The electro-optical device according to the second embodiment is the same as that shown in FIGS. 1 to 3 except that the electro-optical device is operated by quadruple speed driving as shown in FIG. 10 instead of the double speed driving shown in FIG. The configuration is the same as that of the electro-optical device 1 according to the embodiment.
In the following, with respect to the electro-optical device according to the second embodiment, elements having the same functions and functions as those of the first embodiment will be described in detail using the reference numerals referred to in the description of the first embodiment. It abbreviate | omits suitably (it is the same also about each form illustrated below).

FIG. 10 is a timing chart illustrating the operation of the signal generation circuit 20 provided in the electro-optical device according to the second embodiment.
As shown in this figure, each of the plurality of display periods F constituting the operation period of the electro-optical device according to the second embodiment includes a unit period P1, a unit period P2 subsequent to the unit period P1, and a unit period P2. Unit period P3 (an example of “third unit period”) and unit period P4 (an example of “fourth unit period”) subsequent to unit period P3. It is divided.

As shown in FIG. 10, in the second embodiment, the polarity signal P becomes a high level in the unit period P1 and the unit period P3, and becomes a low level in the unit period P2 and the unit period P4. That is, the data line driving circuit 44 according to the second embodiment generates the positive image signal VD [n] in the unit period P1 and the unit period P3, and the negative image signal VD in the unit period P2 and the unit period P4. Generate [n].
In the second embodiment, the reset signal RES is generated when the display period F is started, that is, the other display period following the one display period F after the end of the unit period P4 of the one display period F. It becomes high level at the timing when the unit period P1 of F starts. Further, the calculation unit 24 according to the second embodiment initializes the contents of the integration data DS [1] to DS [N] stored in the storage unit 25 at the timing when the reset signal RES becomes high level.

The light source control unit 22 according to the second embodiment generates a light source control signal Lc based on the control signal Ctr generated by the control unit 21 and supplies this to the light source 12.
As shown in FIG. 10, in the second embodiment, the light source control signal Lc indicates a value LcL for controlling the light source 12 to be turned off in the unit period P1, and the unit period P4 ends from the start of the unit period P2. A value LcH for controlling the light source 12 to be in an on state during the period until this is shown. Therefore, the light source 12 according to the second embodiment is turned off in the unit period P1, and is turned on in the period from the start of the unit period P2 to the end of the unit period P4.

As illustrated in FIG. 10, the correction unit 26 according to the second embodiment performs vertical crosstalk correction in a period during which the light source 12 is on (unit period P2, unit period P3, and unit period P4). During the period when the light source 12 is off (unit period P1), vertical crosstalk correction is not performed.
In the unit period P1, the integration unit 23 according to the second embodiment adds the input image data Din [n] to the integration data DS [n] stored in the storage unit 25, as in the unit period P1 of FIG. As a result, the integrated data DS [n] is updated, and during the period from the start of the unit period P2 to the end of the unit period P4, the integrated data DS [n] stored in the storage unit 25 is stored as in the unit period P2 of FIG. ], The integrated data DS [n] is updated by subtracting a value obtained by doubling the value indicated by the input image data Din [n].

In the electro-optical device 1 according to the first embodiment described above, the light source 12 is turned on in one unit period among the two unit periods constituting the display period F. That is, the period during which the light source 12 is on is only a half of the operation period of the electro-optical device 1.
On the other hand, the electro-optical device according to the second embodiment turns on the light source 12 in three unit periods among the four unit periods constituting the display period F. In other words, in the second embodiment, the light source 12 is maintained in the on state during a period of about 75% of the operation period of the electro-optical device. Therefore, the electro-optical device according to the second embodiment can increase the brightness of the image displayed by the display unit 30 as compared to the first embodiment.

In addition, the electro-optical device according to the second embodiment includes a light source 12 using LEDs, similarly to the electro-optical device 1 according to the first embodiment. The effect of the electro-optical device 1 including the light source 12 using LEDs will be described with reference to FIGS. 11 and 12.
FIG. 11 is a timing chart showing operations of the light source 12 and the liquid crystal 66 according to the second embodiment.
As shown in FIG. 11A, after the image signal VD [n] corresponding to the image data Dx is supplied to the pixel circuit PX, the transmittance of the liquid crystal 66 of the pixel circuit PX is the image data. The time until the transmittance Tdx corresponding to the gradation designated by Dx is reached is time Δtb. Further, as shown in FIG. 11B, when the luminance of the light source 12 in the ON state is L1, the time until the light source 12 becomes a light emitting state with the luminance L1 from the OFF state is defined as time Δta. Usually, the response speed of the LED is faster than the response speed of the liquid crystal 66. Therefore, the time Δta is shorter than the time Δtb. Therefore, as in the second embodiment (and the first embodiment), even when the light source 12 is turned off in the unit period P1, the light source 12 can be turned on promptly when the unit period P2 is started. it can.
Also, as shown in FIG. 11, the time ta when the light source 12 emits light with luminance L1 is earlier than the time tb when the transmittance of the liquid crystal 66 becomes the transmittance Tdx corresponding to the image data Dx, and the unit period P2 Is the time after the start. Therefore, the gradation displayed by the pixel is the gradation specified by the image data Dx at time tb.

FIG. 12 is a timing chart illustrating operations of the light source and the liquid crystal included in the electro-optical device according to the comparative example 2. The electro-optical device according to contrast 2 includes a light source using a cathode tube.
As shown in FIG. 12B, the electro-optical device according to the contrast 2 maintains the light source in the on state. Therefore, the gradation displayed by the pixel becomes the gradation specified by the image data Dx at time tb.

In the electro-optical device according to the comparative example 2, the time length of the period Δtx2 from the start of the display period F until the pixel displays the gradation specified by the image data Dx is longer than the time length of one unit period. . In the period Δtx2, since each pixel cannot accurately display the gradation specified by the image data Dx, the display becomes unclear when a moving image is displayed on the display unit of the electro-optical device according to the proportional 2 or the like. .
On the other hand, in the electro-optical device according to the second embodiment, from when the light source 12 is turned on and the pixels can display a color other than black, until the gradation specified by the image data Dx is displayed. The period Δtx1 is shorter than the period Δtx2. For this reason, in the electro-optical device according to the second embodiment, even when the gradation displayed by the pixel changes for each display period F, such as when a moving image is displayed on the display unit 30, the electro-optical device according to the comparative 2. Compared with the device, the gradation after the change can be accurately displayed, and a clear display is possible.
Note that the electro-optical device 1 according to the first embodiment also includes the light source 12 using LEDs. Therefore, the effect of the electro-optical device according to the second embodiment including the light source 12 using the LED also applies to the electro-optical device 1 according to the first embodiment.

<C. Modification>
Each of the above forms can be variously modified. Specific modifications are exemplified below. Two or more aspects arbitrarily selected from the following examples can be appropriately combined within a range that does not contradict each other.

<Modification 1>
In the embodiment described above, the light source 12 is turned off in the unit period P1, but the present invention is not limited to such a mode, and instead of turning off the light source 12 in the unit period P1, the pixel May display black.

FIG. 13 is a timing chart illustrating the operation of the signal generation circuit included in the electro-optical device according to the first modification.
The electro-optical device according to the modification 1 is different from the first embodiment in that, instead of generating the image data Dx based on the input image data Din, the image data Dx corresponding to black display is generated in the unit period P1. This is different from the electro-optical device 1. Further, the electro-optical device according to the modified example 1 is different from the electro-optical device 1 according to the first embodiment in that the light source control signal Lc is set to the value LcH in the unit period P1 instead of the value LcL. To do. Except for these two differences, the electro-optical device according to the modified example 1 is configured in the same manner as the electro-optical device 1 according to the first embodiment shown in FIGS. 1 to 3. Therefore, in the modification 1, it demonstrates using the code | symbol shown in FIG. 1 thru | or FIG.

As illustrated in FIG. 13, the electro-optical device according to the first modification performs control so that the vertical crosstalk correction is not performed in the unit period P1, and the light source 12 is turned on in the unit period P1.
In the electro-optical device according to the first modification, in the unit period P1, the correction unit 26 generates image data Dx indicating the value Dblk corresponding to black display, thereby displaying black on the pixels included in the display unit 30. Thus, the vertical crosstalk can be prevented from being visually recognized in the unit period P1.
Further, since the correction unit 26 of the electro-optical device according to the modification 1 does not perform the vertical crosstalk correction in the unit period P1, but performs the vertical crosstalk correction only in the unit period P2, the correction unit 26 stores the timing at the start of the unit period P1. The unit 25 can be initialized, and the correction based on the inaccurate integrated data DS [n] can be prevented from being continuously performed over a plurality of display periods F.
Further, since the electro-optical device according to the modification 1 performs the vertical crosstalk correction only in the unit period P2, compared with the case where the vertical crosstalk correction is performed in both the unit period P1 and the unit period P2, the circuit scale and Manufacturing cost can be reduced.
It should be noted that the integration unit 23 of the electro-optical device according to the modified example 1 uses the integration data DS based on the input image data Din and the like in the unit period P1 and the unit period P2, similarly to the integration unit 23 according to the first embodiment. Update [n]. Therefore, the correction unit 26 can perform vertical crosstalk correction using the integration data DS [n] generated by the integration unit 23 in the unit period P2.

<Modification 2>
The data line driving circuit 44 according to the embodiment and the modification described above receives the image signal VD [n] generated based on the image data Dx for each pixel circuit PX via the data line 34 in the unit period P1. However, the present invention is not limited to such a mode, and a predetermined precharge potential or a predetermined reset potential is applied to the data line in part or all of the unit period P1. 34 may be supplied.

<Modification 3>
The electro-optical device according to the embodiment and the modification described above periodically inverts the polarity of the image signal VD [n]. However, the present invention is not limited to such a mode, What is necessary is just to reverse the polarity of the image signal VD [n] based on the rule.
For example, in each display period F, the polarity of the image signal VD [n] is inverted at the period of the unit period, and the polarity of the image signal VD [n] in the unit period P1 of the odd-numbered display period F1 The polarity of the image signal VD [n] may be inverted so that the polarity of the image signal VD [n] in the unit period P1 of the display period F2 is opposite.

FIG. 14 is a timing chart illustrating the operation of the signal generation circuit included in the electro-optical device according to the third modification.
The electro-optical device according to the modified example 3 is different from the image signal VD [n] in that the polarity (the value indicated by the polarity signal P) is inverted based on a predetermined rule instead of being inverted at the period of the unit period. The configuration is the same as that of the electro-optical device 1 according to the first embodiment shown in FIGS. 1 to 3. Therefore, in the modification 3, it demonstrates using the code | symbol shown in FIG. 1 thru | or FIG.

As shown in FIG. 13, in the electro-optical device according to the modification 3, the value indicated by the polarity signal P becomes a high level in the unit period P1 of the odd-numbered display period F1, and the unit period P2 of the odd-numbered display period F1. Becomes the low level in the unit period P1 of the even-numbered display period F2, and becomes the high level in the unit period P2 of the even-numbered display period F2.
For example, as in Modification 2, when a predetermined precharge potential or a predetermined reset potential is supplied to the data line 34 in the unit period P1, the image signal VD in the unit period P1 of all display periods F is supplied. When the polarity of [n] is positive, the polarity balance in the display unit 30 is lost and the display quality is lowered.
On the other hand, as in the third modification example, by changing the polarity of the unit period P1 for each display period F, a predetermined precharge potential or the like is applied to the data line 34 in the unit period P1. In addition, the polarity balance in the display unit 30 can be kept good.

Note that the example shown in FIG. 14 assumes the case of double speed driving, but the electro-optical device according to Modification 3 can also be applied to quadruple speed driving as shown in FIG.
In the example shown in FIG. 15, as in FIG. 14, the polarity of the image signal VD [n] in the unit period P1 of the odd-numbered display period F1 and the image signal VD [n] in the unit period P1 of the even-numbered display period F2. Is the opposite polarity. For this reason, it is possible to keep the polarity balance of the display unit 30 good.

In the case of the example shown in FIG. 14, for example, in the period ΔP1 from the start of the unit period P2 of a certain display period F to the end of the unit period P1 of the display period F following the certain display period F, the image signal VD [n] is maintained at the same polarity (for example, negative polarity). Since the period ΔP1 is a period having the same length as the display period F, there is a concern that image sticking or the like may occur and the display quality of the display unit 30 may deteriorate.
On the other hand, in the case of the example shown in FIG. 15, the image signal VD in the period ΔP2 from the start of the unit period P4 of a certain display period F to the end of the unit period P1 of the display period F subsequent to the certain display period F. Although [n] is maintained at the same polarity, the period ΔP2 is a period shorter than the display period F, so that the probability of occurrence of image sticking or the like can be suppressed, and the display quality can be reduced. Can be deterred.

<Modification 4>
The electro-optical device according to the embodiment and the modification described above controls the light source 12 so that the luminance of the light source 12 gradually increases to a predetermined luminance L1 when the light source 12 is turned on. As shown in FIG. 16B, when the light source 12 is turned on, first, the light source 12 emits light with a luminance L2 higher than the luminance L1, and then the unit period. When the predetermined time Δtc has elapsed from the start of P2, the light source 12 may be controlled so that the luminance of the light source 12 converges to the luminance L1. That is, the electro-optical device may control the luminance of the light source 12 so as to cause overshoot when the light source 12 is turned on.
In the electro-optical device according to the modified example 4, as shown in FIG. 16C, the brightness of the image displayed on the display unit 30 as compared with the case where no overshoot as shown in FIG. Can be brightened, and sufficient brightness can be ensured even when the light source 12 is turned off in the unit period P1.

<D. Application example>
The electro-optical device 1 exemplified in the above embodiments can be used in various electronic apparatuses. 17 to 19 exemplify specific forms of electronic devices that employ the electro-optical device 1.

  FIG. 17 is a schematic diagram of a projection display device (three-plate projector) 4000 to which the electro-optical device 1 is applied. The projection display device 4000 includes three electro-optical devices 1 (10R, 10G, and 10B) corresponding to different display colors (red, green, and blue). The illumination optical system 4001 supplies the red component r of the light emitted from the illumination device (light source) 4002 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 1 functions as a light modulator (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 the emitted light from each electro-optical device 1 and projects it onto the projection surface 4004. An observer visually recognizes an image projected on the projection surface 4004.

  FIG. 18 is a perspective view of a portable personal computer 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. 19 is a perspective view of a mobile phone to which the electro-optical device 1 is applied. 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.

  Note that electronic devices to which the electro-optical device according to the invention is applied include the devices exemplified in FIGS. 17 to 19, personal digital assistants (PDAs), digital still cameras, televisions, video cameras, Car navigation devices, in-vehicle displays (instrument panels), electronic notebooks, electronic paper, calculators, word processors, workstations, videophones, POS terminals, printers, scanners, copiers, video players, equipment with touch panels, etc. Can be mentioned.

DESCRIPTION OF SYMBOLS 1 ... Electro-optical apparatus, 10 ... Electro-optical panel, 12 ... Light source, 20 ... Signal generation circuit, 21 ... Control part, 22 ... Light source control part, 23 ... Integration part, 24 ... Calculation part , 25... Storage unit, 26... Correction unit, 30... Display unit, 32... Scanning line, 34... Data line, 40. Drive circuit 50... Display control circuit 60... Liquid crystal element 66.

Claims (10)

An electro-optical device including a data line, a pixel circuit provided corresponding to the data line, and a light source, supplies an image signal to the pixel circuit via the data line, and A display control circuit for controlling operation,
The operation of the light source is performed such that the light source is turned off in a first unit period of the display period, and the light source is turned on in a second unit period of the display period following the first unit period. A light source controller to control;
In the second unit period, the voltage of the image signal supplied to the data line is integrated from the past to the present for one unit period based on the input image data supplied from the start of the display period to the present. An integration unit for generating integration data corresponding to the integral value;
A vertical crosstalk correction unit that corrects current input image data and generates image data based on the integrated data in the second unit period;
A drive unit that generates the image signal based on the image data, and supplies the generated image signal to the pixel circuit via the data line;
The drive unit generates the image signal based on the image data that has not been corrected by the vertical crosstalk correction unit in the first unit period, and the vertical crosstalk correction in the second unit period. A display control circuit that generates the image signal based on the image data corrected by a unit . An electro-optical device including a data line, a pixel circuit provided corresponding to the data line, and a light source, supplies an image signal to the pixel circuit via the data line, and A display control circuit for controlling operation,
The operation of the light source is performed such that the light source is turned off in a first unit period of the display period, and the light source is turned on in a second unit period of the display period following the first unit period. A light source controller to control;
In the second unit period, the voltage of the image signal supplied to the data line is integrated from the past to the present for one unit period based on the input image data supplied from the start of the display period to the present. An integration unit for generating integration data corresponding to the integral value;
A correction unit that corrects current input image data to generate image data based on the accumulated data in the second unit period;
A drive unit that generates the image signal based on the image data, and supplies the generated image signal to the pixel circuit via the data line;
With
The display period is
Including the first unit period, the second unit period, a third unit period following the second unit period, and a fourth unit period following the third unit period,
The light source controller is
Controlling the operation of the light source so as to maintain the light source in an on state in a period from the start of the second unit period to the end of the fourth unit period;
The integrating unit is
In the third unit period and the fourth unit period, the voltage of the image signal supplied to the data line is set to 1 based on the input image data supplied from the start of the display period to the present. Generate integration data corresponding to the integration value integrated from the past to the present for the unit period,
The correction unit is
In the third unit period and the fourth unit period, based on the integration data, the current input image data is corrected to generate the image data.
A display control circuit. The correction unit is
In the first unit period,
An image signal is generated based on the input image data of
The drive unit is
In the display period, the image signal is generated so that the polarity of the signal is inverted around a reference level in a predetermined cycle,
The integrating unit is
In the display period, by performing one of addition and subtraction of the input image data according to the polarity of the image signal, the input image data from the start of the display period to the present is integrated, and the integrated data Generate
The display control circuit according to claim 1, wherein the display control circuit is a display control circuit. The predetermined cycle is a cycle of the unit period,
The integrating unit is
A storage unit for storing the integrated data;
In the first unit period, by writing the data obtained by adding the current input image data and the data read from the storage unit to the storage unit, the storage content of the storage unit is updated,
Of the display period, in the period after the end of the first unit period, new accumulated data calculated based on the accumulated data read from the storage unit and current input image data is stored in the storage unit. Update the storage content of the storage unit by writing to
A calculation unit that initializes the storage content of the storage unit at the end of the display period;
With
The drive unit is
Reversing the polarity of the image signal for each unit period;
The display control circuit according to claim 3, wherein: The drive unit is
The polarity of the image signal in the first unit period of one display period and the polarity of the image signal in the first unit period of another display period following the one display period are opposite to each other. Generating the image signal;
The display control circuit according to claim 4, wherein: The first unit period is
It consists of a first partial period and a second partial period,
The drive unit is
Supplying the image signal to the data line in the first partial period;
In the second partial period, a predetermined precharge potential is supplied to the data line.
The display control circuit according to claim 2, wherein the display control circuit is a display control circuit. When the second unit period starts, the light source control unit increases the luminance of the light source beyond a predetermined luminance, and when a predetermined time elapses from the start of the second unit period, the luminance of the light source Turning on the light source to converge to the predetermined brightness;
The display control circuit according to claim 2, wherein the display control circuit is any one of claims 2 to 6. A display control circuit that is provided in a display device including a data line and a pixel circuit provided corresponding to the data line, and that supplies an image signal to the pixel circuit via the data line;
In the second unit period following the first unit period in the display period,
Based on input image data supplied from the start of the display period to the present, an integration unit that generates integrated data obtained by integrating the input image data from the start of the display period to the present;
In the first unit period, the pixel data corresponding to the pixel circuit generates image data corresponding to the image signal that displays black, and in the second unit period, based on the integrated data, the current input A correction unit that corrects image data to generate image data;
A drive unit that generates the image signal based on the image data and supplies the generated image signal to the pixel circuit via the data line;
The display period is
Including the first unit period, the second unit period, a third unit period following the second unit period, and a fourth unit period following the third unit period,
The integrating unit is
In the third unit period and the fourth unit period, the voltage of the image signal supplied to the pixel circuit is set to 1 based on input image data supplied from the start of the display period to the present. Generate integration data corresponding to the integration value integrated from the past to the present for the unit period,
The correction unit is
In the third unit period and the fourth unit period, based on the integrated data, current input image data is corrected to generate image data.
A display control circuit. A display control circuit according to any one of claims 1 to 7,
A data line, a pixel circuit provided corresponding to the data line, a light source,
An electro-optical device comprising:
The pixel circuit includes a liquid crystal element,
The light source emits light with a predetermined brightness in an on state,
In the second unit period, the time when the luminance of the light source becomes the predetermined luminance is earlier than the time when the transmittance of the pixel corresponding to the pixel circuit becomes the transmittance corresponding to the image signal.
An electro-optical device.   An electronic apparatus comprising the electro-optical device according to claim 9.

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