JP6322933B2 - Electro-optical device, electronic apparatus, and control method of electro-optical device - Google Patents

Description

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

  The liquid crystal display device is configured to sandwich a liquid crystal between a pixel electrode and a common electrode. It is known that when a DC voltage is applied to the liquid crystal capacitor, an afterimage is generated, which deteriorates display quality and deteriorates long-term reliability. One possible reason is that a small amount of an ionic substance is mixed in the process of sealing the liquid crystal between the electrodes when the liquid crystal display device is manufactured. Even if the ionic substance is sealed, the ionic substance does not accumulate on the electrodes and does not affect the alignment of the liquid crystal molecules if an ideal alternating current signal is applied between the electrodes.

  However, if a direct current component is included in the voltage applied between the electrodes, the ionic substance is attracted to one of the electrodes and accumulated on the electrodes. When ionic substances are accumulated on the electrodes in this way, the voltage applied to the liquid crystal is influenced by the ionic substances accumulated on the electrodes even if an AC signal corresponding to the gradation to be displayed is applied between the electrodes. Therefore, the alignment of the liquid crystal molecules is controlled by a voltage different from the actual voltage. For this reason, when a large amount of the ionic substance is superimposed on the electrode, the voltage applied to the liquid crystal changes greatly, and the luminance difference from other pixels where the ionic substance is not superimposed on the electrode becomes large. This is visually recognized as an afterimage.

  By the way, when the user turns off the power of the liquid crystal display device, the supply of various signals (scanning line drive signal, data line drive signal, etc.) to the liquid crystal display panel is cut off and stored in the liquid crystal capacity of the liquid crystal display panel. The external discharge path of the charged charge is interrupted. Thereafter, the charge gradually decreases due to self-discharge, and the display image is gradually cleared. However, if the state in which the charge is accumulated in the liquid crystal capacitor is held for a long time, an afterimage is generated.

  In order to solve such a problem, Patent Document 1 discloses data of a predetermined potential in order to forcibly discharge the charge accumulated in the liquid crystal capacitor for a predetermined time after detecting the non-input state of the input signal. A technique for shortening the time for applying a DC voltage to a liquid crystal by writing a signal to a pixel electrode is disclosed.

JP 2001-209355 A

By the way, the degree to which the ionic substance that causes burn-in is accumulated on the pixel electrode and the common electrode varies depending on the use conditions such as temperature and use time. However, in the conventional liquid crystal display device, the electric charge accumulated in the liquid crystal capacitance is discharged for a certain time regardless of the usage situation, so that the discharge is not sufficient and ionic substances that cause burn-in remain on the electrode. Alternatively, there is a possibility that a data signal is written unnecessarily even after the discharge of electric charge has been completed.
The present invention has been made in view of the above-described circumstances, and an object of the present invention is to appropriately discharge charges accumulated in various capacitors when the power is turned off.

  In order to solve the above-described problem, an aspect of the electro-optical device according to the present invention includes a pixel electrode, a common electrode, and an electro-optical material sandwiched between the pixel electrode and the common electrode. A timing unit that counts a usage time from when the power source is turned on until a signal indicating that the power source is transitioned to the off state is detected, and the potential of the pixel electrode and the potential of the common electrode, And a control unit that executes an off-sequence process for bringing the time closer to the predetermined time according to the usage time.

  According to one aspect of the electro-optical device, the time for performing the off-sequence process is varied according to the usage time, so that the charge accumulated in the capacitor between the pixel electrode and the common electrode can be reliably discharged. it can. In addition, even if an ionic substance is sealed in the electro-optical device in the manufacturing process and an amount corresponding to the usage time is accumulated on the electrode, the off-sequence processing is executed only for the time corresponding to the usage time, so that the display quality and device Reliability can be improved.

  Here, it is preferable that the control unit increases the time for executing the off sequence process as the usage time increases. This is because the amount of ionic substance that accumulates on the electrode increases as the use time increases. Further, the electro-optical material is a material whose optical characteristics are changed by electric energy, and examples thereof include liquid crystal and organic EL.

  Another aspect of the electro-optical device according to the present invention includes a pixel electrode, a common electrode, and an electro-optical material sandwiched between the pixel electrode and the common electrode, and the power is turned off. The temperature detection unit that detects the temperature at the time of detecting the signal indicating that the signal is to be shifted to, and the off-sequence process that brings the potential of the pixel electrode and the potential of the common electrode closer according to the temperature detected by the temperature detection unit And a control unit that executes only for a predetermined time.

According to another aspect of the electro-optical device, the time for performing the off-sequence process is varied according to the temperature, so that the charge accumulated in the capacitor between the pixel electrode and the common electrode can be reliably discharged. it can. In addition, even if an ionic substance is sealed in the electro-optical device in the manufacturing process and an amount corresponding to the temperature is accumulated on the electrode, the off-sequence process is performed for a time corresponding to the temperature, so that the display quality and device reliability are improved. Can be improved.
Here, it is preferable that the control unit lengthens the time for performing the off sequence process as the temperature increases. This is because the higher the temperature, the greater the amount of ionic substance that accumulates on the electrode.

Another aspect of the electro-optical device according to the present invention includes a pixel electrode, a common electrode, and an electro-optical material sandwiched between the pixel electrode and the common electrode, and the power supply is in an on state. Detects the temperature at the time of detecting the signal indicating that the power source is changed to the OFF state, and the time measuring unit that measures the usage time until the signal indicating that the power source is changed to the OFF state is detected. A temperature detection unit; and a control unit that executes an off-sequence process for bringing the pixel electrode potential and the common electrode potential close to each other for a time corresponding to the use time and the temperature detected by the temperature detection unit. It is characterized by.
According to this aspect, since the off sequence process is executed only for the time corresponding to both the usage time and the temperature, the display quality and the reliability of the apparatus can be further improved.

Next, an aspect of the electronic apparatus according to the invention includes a plurality of electro-optical panels and a control unit, and each of the plurality of electro-optical panels is provided between the pixel electrode and the common electrode. An electro-optical material sandwiched between and a temperature detection unit that detects a temperature at the time of detecting a signal indicating that the power supply is turned off, and the control unit is provided in each of the plurality of electro-optical panels. Among the temperatures detected by the temperature detection unit provided, the plurality of electrical operations are performed so as to execute an off-sequence process that brings the potential of the pixel electrode and the potential of the common electrode closer for a time corresponding to the highest temperature. Control the optical panel.
According to one aspect of this electronic apparatus, the temperature varies depending on the use state of each of the plurality of electro-optical panels, but the off-sequence process is executed for a time corresponding to the highest temperature. Accumulation of substances on the electrode can be eliminated.

Next, another electronic apparatus according to the present invention includes a plurality of electro-optical panels including an electro-optical panel corresponding to G color, and a control unit, and each of the plurality of electro-optical panels includes: A pixel electrode, a common electrode, and an electro-optical material sandwiched between the pixel electrode and the common electrode, and the electro-optical panel corresponding to the G color includes a temperature detection unit that detects temperature, The control unit brings the potential of the pixel electrode and the potential of the common electrode close to each other for a time corresponding to the temperature detected by the temperature detection unit at the time of detecting a signal indicating that the power supply is switched to the off state. The plurality of electro-optical panels are controlled so as to perform off-sequence processing.
The electro-optical panel corresponding to the G color has a higher brightness than the other colors, so that the temperature is highest, but according to the other electronic device according to the present invention, the G color electric Although the optical device is provided with a temperature detection unit to detect the temperature, it is not necessary to provide a temperature detection unit for other electro-optical devices. Therefore, the configuration of the electronic device can be simplified.

Next, an aspect of the method for controlling the electro-optical device according to the invention includes an electro-optical device including a pixel electrode, a common electrode, and an electro-optical material sandwiched between the pixel electrode and the common electrode. A method of controlling, detecting a use situation from when a power source is turned on until a signal indicating that the power source is transitioned to an off state is detected, and the potential of the pixel electrode and the potential of the common electrode The off-sequence process for bringing the two close to each other is executed only for a time corresponding to the detected use state.
According to this aspect, since the off-sequence process is executed for a time corresponding to the usage situation, the charge accumulated in the capacitor between the pixel electrode and the common electrode can be reliably discharged. In addition, even if an ionic substance is sealed in the electro-optical device in the manufacturing process and an amount corresponding to the usage state is accumulated on the electrode, the off-sequence processing is performed for a time corresponding to the usage state, so that the display quality and device Reliability can be improved.

1 is a block diagram illustrating a configuration of an electro-optical device according to an embodiment of the invention. FIG. It is a circuit diagram which shows an example of a structure of the image display area A in liquid crystal panel AA. 3 is a timing chart showing an example of operations of a scanning line driving circuit 100 and a data line driving circuit 200 of the same device. It is a flowchart which shows operation | movement of the control circuit of the apparatus. It is a timing chart for explaining off sequence processing. It is the external appearance perspective view which looked at the digital camera which concerns on an application example from the back side. It is a block diagram which shows the electric constitution of the digital camera which concerns on an application example. It is explanatory drawing which shows the structure of the projection type display apparatus which concerns on an application example. It is a block diagram which shows the electric constitution of the projection type display apparatus which concerns on an application example. It is explanatory drawing for demonstrating the off sequence time which concerns on a modification.

<Embodiment>
FIG. 1 shows a configuration of an electro-optical device 1 using a liquid crystal panel AA. The electro-optical device 1 includes a liquid crystal panel AA and a drive control unit D. The liquid crystal panel AA is bonded to an element substrate on which a thin film transistor (hereinafter referred to as “TFT”) is formed as a switching element and a counter substrate with the electrode formation surfaces facing each other and maintaining a certain gap. However, liquid crystal is sandwiched between the gaps. The liquid crystal panel AA includes an image display area A, a scanning line driving circuit 100, a data line driving circuit 200, and a temperature sensor 60 on the element substrate. In the image display area A, a plurality of pixel circuits P1 are formed in a matrix, and the transmittance can be controlled for each pixel circuit P1. Light from a backlight (not shown) is emitted through the pixel circuit P1. Thereby, gradation display by light modulation becomes possible. The temperature sensor 60 is provided outside the image display area A so as not to affect the display image, but is formed on the element substrate so that the temperature of the liquid crystal can be detected.

In the image display area A, as shown in FIG. 2, m (m is a natural number of 2 or more) scanning lines 2 are formed in parallel along the X direction, while n (n is (Natural number of 2 or more) number of data lines 3 are arranged in parallel along the Y direction. In the vicinity of the intersection of the scanning line 2 and the data line 3, the gate of the TFT 50 is connected to the scanning line 2, while the source of the TFT 50 is connected to the data line 3 and the drain of the TFT 50 is connected to the pixel electrode 6. Connected. Each pixel includes a pixel electrode 6, a counter electrode (described later) formed on the counter substrate, and a liquid crystal sandwiched between the two electrodes. As a result, the pixels are arranged in a matrix corresponding to each intersection of the scanning line 2 and the data line 3.
Further, scanning signals Y1, Y2,..., Ym are applied in a pulse-sequential manner to each scanning line 2 to which the gate of the TFT 50 is connected. Therefore, when a scanning signal is supplied to a certain scanning line 2, the TFT 50 connected to the scanning line is turned on, so that the data signals X1, X2,..., Xn supplied from the data line 3 at a predetermined timing are After being written in order to the corresponding pixels, they are held for a predetermined period.

In the pixel circuit P1, since the alignment and order of liquid crystal molecules change according to the voltage level applied to each pixel, gradation display by light modulation is possible. For example, in the normally white mode, the amount of light passing through the liquid crystal is limited as the applied voltage increases, whereas in the normally black mode, the amount of light is reduced as the applied voltage increases. As a whole, light having contrast according to the image signal is emitted for each pixel. For this reason, a predetermined display becomes possible.
In order to prevent the held image signal from leaking, a storage capacitor 51 is added in parallel with a liquid crystal capacitor formed between the pixel electrode 6 and the counter electrode. For example, the voltage of the pixel electrode 6 is held by the storage capacitor 51 for a time that is three orders of magnitude longer than the time when the source voltage is applied, so that the holding characteristics are improved, so that a high contrast ratio is realized.

  Next, the drive control unit D will be described. As shown in FIG. 1, the drive control unit D supplies power to each component of the time measuring circuit 500 that measures time, the control circuit 600 that controls the entire electro-optical device 1, the liquid crystal panel AA, and the drive control unit D. In addition, a power supply circuit 700 that supplies a common potential Vcom to the common electrode of the liquid crystal panel AA, a timing generation circuit 800 that generates various timing control signals, and an image that performs gamma correction on the input image data Din to generate an image signal VID The signal generation circuit 900 includes a table TBL that stores temperature and use time in association with off-sequence time.

  The control circuit 600 is supplied with a power operation signal Cdi indicating a result of detecting that the user has operated the power switch to switch from on to off. The power operation signal Cdi changes from L level to H level when the user performs power on operation with the power off, and from H level when the user performs power off operation with the power on. Changes to L level.

  FIG. 3 shows a timing chart of the scanning line driving circuit 100 and the data line driving circuit 200. The scanning line driving circuit 100 sequentially shifts the Y transfer start pulse DY of one frame (1F) cycle in accordance with the Y clock signal YCK to generate the scanning signals Y1, Y2,. The scanning signals Y1 to Ym are sequentially activated in each horizontal scanning period (1H). The data line driving circuit 200 transfers the X transfer start pulse DX of the horizontal scanning period in accordance with the X clock signal XCK, and internally generates sampling signals S1, S2,. Then, the data line driving circuit 200 samples the image signal VID using the sampling signals S1, S2,... Sn to generate data signals X1, X2,.

The control circuit 600 sets the common potential Vcom supplied to the common electrode to the ground potential and supplies the ground potential to the pixel electrode 51 instead of immediately shutting off the power even when the user operates the power switch to turn off. The off sequence process is executed. The charge accumulated in the liquid crystal capacitor is discharged by the off-sequence process, and burn-in can be prevented.
The cause of image sticking is that the ionic substance mixed in the process of encapsulating the liquid crystal is accumulated on the common electrode or the pixel electrode 6 by direct current application. That is, the orientation of the liquid crystal molecules is controlled by the accumulated ionic substance at a voltage different from the actual voltage. Here, the degree to which the ionic substance is accumulated on the pixel electrode 6 and the common electrode varies depending on the use situation such as temperature and use time. When the temperature is high, the degree of integration increases, and when the operating time is long, the degree of integration also increases.
In the present embodiment, the off sequence time for executing the off sequence process is determined according to the usage situation. More specifically, the control circuit 600 determines the off sequence time based on the temperature of the liquid crystal detected by the temperature sensor 60 and the usage time measured by the time measuring circuit 500.

  FIG. 4 is a flowchart showing the operation of the control circuit. The control circuit 600 monitors the power operation signal Cdi, determines whether or not the user's power-on operation is detected (step S1), and repeats until the power-on operation is detected. When the power operation signal Cdi transitions from the L level to the H level, the control circuit 600 detects a power on operation and executes a power on process (step S2). In the power-on process, the control circuit 600 supplies the power supply circuit 700 with a power supply control signal Vc instructing to start power supply. Then, the power supply circuit 700 supplies a common potential Vcom to the common electrode and supplies power to each unit. Next, the control circuit 600 causes the timer circuit 500 to start measuring time (step S3). Thereby, the time measuring circuit 500 starts measuring the time after the power is turned on.

  Thereafter, the control circuit 600 monitors the power operation signal Cdi, determines whether or not the user's power-off operation is detected (step S4), and repeats the process until the power-off operation is detected. When the power operation signal Cdi transitions from the H level to the L level, the control circuit 600 detects a power off operation. Next, the control circuit 600 acquires the usage time with reference to the time measuring circuit 500 (step S5). Subsequently, the control circuit 600 acquires the temperature of the liquid crystal based on the temperature signal output from the temperature sensor 60 (step S6).

  Next, the control circuit 600 determines the off sequence time based on the use time and temperature (step S7). Specifically, the control circuit 600 reads the off sequence time stored in association with the use time and the temperature with reference to the table TBL. If the use time is the same, the off sequence time becomes longer as the temperature becomes higher, and if the temperature is the same, the off sequence time becomes longer as the use time becomes longer.

  Next, the control circuit 600 starts off-sequence processing. Specifically, the control circuit 600 causes the timer circuit 500 to start timing. The control circuit 600 controls the power supply circuit 700 so as to supply the ground potential as the common potential Vcom and also controls the image signal generation circuit 900 so as to supply the ground potential as the image signal VID. That is, in the off sequence process, a process of bringing the potential of the pixel electrode close to the potential of the common electrode is performed.

  As shown in FIG. 5, when the power operation signal Cdi falls at time t0, the off sequence process starts. A control signal CTL is supplied to the image signal generation circuit 900. The control signal CTL is at the H level during the off sequence time. The image signal generation circuit 900 generates a ground potential as the image signal VID while the control signal CTL is at the H level. As a result, the ground potential is written to the pixel electrode 6 of each pixel circuit P1 through the data line 3 during the off sequence time. On the other hand, in this example, the common potential Vcom is a ground potential during a period in which the data potential corresponding to the gradation to be displayed is written to the pixel circuit P1, and thus the ground potential is maintained during the off sequence time. In consideration of the characteristics of the selection transistor 50, the common potential Vcom may be slightly offset from the ground potential in the period in which the data potential is written to the pixel circuit P1. In this case, the ground potential is supplied to the common electrode and the pixel electrode during the off sequence time. This is because when the power supply is turned off, the potential of the pixel electrode and the potential of the common electrode gradually approach the ground potential due to discharge.

  Returning to FIG. When step S8 ends, the control circuit 600 determines whether or not the off sequence time has elapsed (step S9). Specifically, the timing result of the timing circuit 500 is monitored, and it is determined whether or not this matches the off sequence time. When the off sequence time has elapsed, the determination result in step S9 is YES, and the control circuit 600 supplies the power supply control signal Vc instructing the power supply circuit 700 to turn off the power. The power supply circuit 700 detects the falling edge of the power supply control signal Vc and stops the supply of power.

  As described above, according to the present embodiment, the off sequence time is set according to the usage situation such as the usage time and the temperature. Therefore, when the usage time is long or the temperature is high, the off sequence time is lengthened to the electrode. Thoroughly eliminate accumulated ionic substances. On the other hand, when the usage time is short or the temperature is low, the off-sequence time is shortened, so that power consumption can be reduced and user convenience can be improved.

<Application example>
The electro-optical device 1 described above can be applied to various electronic devices.
FIG. 6 is an external perspective view of the digital camera 1000 (imaging device) using the electro-optical device 1 according to the embodiment of the present invention as seen from the back side, and FIG. 7 is a block diagram of the digital camera 1000. As shown in the figure, the digital camera 1000 includes a lens 11, an image sensor 12, a processing circuit 13, a display unit 16, a storage unit 17, an operation unit 18, and a CPU 15 that controls each unit. The image sensor 12 receives an optical image from a subject captured by the lens 11 and converts it into an electrical signal. The processing circuit 13 converts the electrical signal output from the image sensor 12 into a digital image signal. Under the control of the CPU 15, the digital image is sent to the display unit 16, the storage unit 17, a memory card (not shown), and the like for processing.

The display unit 16 is an LCD (Liquid Crystal Display) display unit disposed on the back of the digital camera 1000, and displays an observation image (captured image) of a subject at the time of shooting, or a shot image recorded on a memory card. Is used for playback display.
The storage unit 17 includes a nonvolatile memory (for example, a flash memory) and a volatile memory (for example, a RAM: Random Access Memory). The former stores a camera program for causing the camera to perform various operations, and the latter is used as a work area of the CPU 15.
The operation unit 18 includes a release button 18a, a power button 18b, a cursor button / decision button 18c, and other operation buttons (not shown), and the CPU 15 performs power on / off control based on instructions from various buttons. Various controls such as display image switching on the display unit 16 are performed.

  An eyepiece 20a for a photographer to look into is provided on the back of the digital camera 1000, and an electronic view finder (EVF) 20 is provided inside the main body corresponding to the eyepiece 20a. Is provided. The EVF 20 includes a liquid crystal panel AA and a drive control unit D that drives the liquid crystal panel AA, and corresponds to the electro-optical device 1 described above.

  FIG. 8 is a schematic diagram illustrating a configuration of a projection display device (three-plate projector) 4000 using the electro-optical device 1 according to the embodiment of the invention, and FIG. 9 is an electrical diagram of the projection display device 4000. It is a block diagram which shows the principal part of a structure. The projection display device 4000 includes three electro-optical devices 1R, 1G, and 1B that respectively correspond to different display colors R, G, and B. However, the electro-optical devices 1R, 1G, and 1B are configured by removing the table TBL, the control circuit 600, and the timing circuit 500 from the electro-optical device 1 shown in FIG.

  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 1R, 1G, and 1B functions as an optical 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 the electro-optical devices 1R, 1G, and 1B and projects the synthesized light onto the projection surface 4004.

  As shown in FIG. 9, the control circuit 600 and the table TBL are provided in common to the electro-optical devices 1R, 1G, and 1B. Here, the electro-optical devices 1R, 1G, and 1B have common use times, but have different temperatures. Accordingly, the off-sequence times corresponding to the electro-optical devices 1R, 1G, and 1B are also different. The control circuit 600 sets the off sequence time of each device to the longest off sequence time. For example, the off-sequence time of the electro-optical device 1R corresponding to the R color is 100 frames, the off-sequence time of the electro-optical device 1G corresponding to the G color is 220 frames, and the off-sequence time of the electro-optical device 1B corresponding to the B color In the case of 130 frames, the off sequence time of all the electro-optical devices 1R, 1G, and 1B is set to 220 frames.

  Thus, the reason why the longest off-sequence time is adopted is as follows. Since each RGB color has different off sequence times, even if the off sequence times are set separately, the power supply of the entire apparatus is not turned off until the longest off sequence time ends. On the other hand, even if the off-sequence process is executed so as to align with the longest off-sequence time, there is no inconvenience because the discharge of the liquid crystal capacitance is repeated.

  Incidentally, among the electro-optical devices 1R, 1G, and 1B corresponding to RGB colors, the temperature of the electro-optical device 1G corresponding to the G color is often the highest. This is because the sensitivity of the human eye is higher for the G color than the R and B colors, and the luminance of the electro-optical device 1G is higher than that of the electro-optical devices 1R and 1B. Therefore, the off sequence time determined based on the temperature of the electro-optical device 1G may be applied to the electro-optical devices 1R and 1B. In this case, it is not necessary to provide the temperature sensor 60 in the electro-optical devices 1R and 1B. Therefore, the configuration can be simplified.

<Modification>
The present invention is not limited to the embodiments and application examples described above, and various modifications described below are possible. Moreover, you may combine each embodiment, each application example, and each modification suitably.
(1) In the above-described embodiment, the temperature at the time of detecting the signal indicating that the power source is changed to the off state has been described as an example of the usage state, but the present invention is not limited to this. The time for executing the off sequence process may be determined according to the temperature history from when the power source is turned on until the signal indicating that the power source is transitioned to the off state is detected. For example, it is assumed that the temperature history is given by the function T (t), changes as shown in FIG. 10, the power source is turned on at time t0, and a signal for switching the power source to the off state is detected at time t1. In this case, the off sequence time may be determined according to the area of the hatched portion shown in FIG. More specifically, the off sequence time is determined according to Equation 1 shown in FIG. Also in this case, it is preferable to increase the off sequence time as the use time is longer and the temperature is higher.

(2) In the above-described embodiment, the off-sequence time is determined based on two factors such as the use time and the temperature. However, the present invention is not limited to this, and the off-sequence time is based on either one. Time may be determined. For example, the off-sequence time may be determined according to the usage time, or the off-sequence time may be determined according to the temperature. In this case, it is preferable to increase the off sequence time as the use time becomes longer, and to increase the off sequence time as the temperature becomes higher.

(3) In the above-described embodiment, the usage time and temperature have been described as examples of usage situations. However, the present invention is not limited to this, and off-sequence processing is performed according to the usage status of the electro-optical device. You may define the time to perform. The usage status may be the physical properties of the liquid crystal as an electro-optical material or the manufacturing process. In short, as long as the electro-optical device is used in connection with the accumulation of ionic substances, any device may be measured, and the off-sequence processing time may be determined according to the measurement result.
In the above-described embodiment, the off sequence time is determined with reference to the table TBL. However, the present invention is not limited to this, and the off sequence time may be determined by calculation.

(4) In the embodiment and the modification, it is assumed that the liquid crystal panel AA is used. However, the present invention is not limited to this, and an off sequence is performed between the end of image display and power off. The present invention can be applied to a display panel that preferably performs processing. For example, an organic EL panel using organic EL (Electroluminescence) as an electro-optical material whose optical characteristics change depending on electric energy may be used.
A pixel of the organic EL panel includes an organic EL element and a driving transistor that supplies current to the organic EL element. The current flowing through the organic EL element is determined by the gate voltage of the driving transistor. For this reason, it is preferable to set the gate voltage to a predetermined voltage in the off-sequence process.
That is, the present invention can be applied to an electro-optical panel including an electro-optical material such as a liquid crystal panel AA or an organic EL panel.

DESCRIPTION OF SYMBOLS 2 ... Scan line, 3 ... Data line, 6 ... Pixel electrode, 20 ... EVF, 100 ... Scan line drive circuit, 200 ... Data line drive circuit, 500 ... Time measuring circuit, 600 ... Control circuit (control part), 700 ... Power supply Circuit, 800 ... Timing generation circuit, 900 ... Image signal generation circuit, TBL ... Table, AA ... Liquid crystal panel, Cdi ... Power supply operation signal, D ... Drive control unit, P1 ... Pixel circuit, 1000 ... Digital camera, 4000 ... Projection type Display device.

Claims (8)

An electro-optical device having a pixel electrode, a common electrode, and a liquid crystal sandwiched between the pixel electrode and the common electrode,
A timing unit that counts the usage time from when the power source is turned on until a signal indicating that the power source is transitioned to the off state is detected;
A control unit that executes an off-sequence process of bringing the potential of the pixel electrode and the potential of the common electrode closer to each other according to the usage time;
An electro-optical device comprising: Wherein the control unit, as the said operating time becomes longer, a longer time to perform the off-sequence process, the electro-optical device according to claim 1, characterized in that. An electro-optical device having a pixel electrode, a common electrode, and a liquid crystal sandwiched between the pixel electrode and the common electrode,
A temperature detection unit that detects a temperature at the time of detecting a signal indicating that the power supply is shifted to an off state;
A control unit that performs off-sequence processing for bringing the potential of the pixel electrode and the potential of the common electrode closer to each other for a time corresponding to the temperature detected by the temperature detection unit;
Bei to give a,
The control unit increases the time for performing off-sequence processing as the temperature increases.
An electro-optical device. An electro-optical device having a pixel electrode, a common electrode, and a liquid crystal sandwiched between the pixel electrode and the common electrode,
A timing unit that counts the usage time from when the power source is turned on until a signal indicating that the power source is transitioned to the off state is detected;
A temperature detection unit that detects a temperature at the time of detecting a signal indicating that the power supply is shifted to an off state;
A control unit that executes off-sequence processing for bringing the potential of the pixel electrode and the potential of the common electrode closer to each other according to the use time and the temperature detected by the temperature detection unit;
An electro-optical device comprising: An electronic device including a plurality of electro-optical panels and a control unit,
Each of the plurality of electro-optic panels is
A pixel electrode, a common electrode, and a liquid crystal sandwiched between the pixel electrode and the common electrode;
A temperature detection unit that detects a temperature at the time of detecting a signal indicating that the power supply is transitioned to an off state;
The control unit includes a potential of the pixel electrode and a potential of the common electrode for a time corresponding to the highest temperature among the temperatures detected by the temperature detection unit provided in each of the plurality of electro-optical panels. Controlling the plurality of electro-optic panels to perform an off-sequence process for bringing
An electronic device characterized by that. An electronic apparatus including a plurality of electro-optical panels including an electro-optical panel corresponding to G color, and a control unit,
Each of the plurality of electro-optical panels includes a pixel electrode, a common electrode, and a liquid crystal sandwiched between the pixel electrode and the common electrode.
The electro-optical panel corresponding to the G color includes a temperature detection unit that detects temperature,
The control unit brings the potential of the pixel electrode and the potential of the common electrode close to each other for a time corresponding to the temperature detected by the temperature detection unit at the time of detecting a signal indicating that the power supply is switched to the off state. Controlling the plurality of electro-optic panels to perform off-sequence processing;
An electronic device characterized by that. A control method of an electro-optical device having a pixel electrode, a common electrode, and a liquid crystal sandwiched between the pixel electrode and the common electrode,
Obtain the usage time from when the power is turned on to when the signal indicating that the power is turned off is detected ,
Off sequence process to approach the potential of said common electrode of said pixel electrodes, executes for a time corresponding to between the time for obtaining beneath used,
A control method for an electro-optical device. A control method of an electro-optical device having a pixel electrode, a common electrode, and a liquid crystal sandwiched between the pixel electrode and the common electrode,
Obtain the temperature at the time of detecting the signal indicating that the power supply is turned off ,
An off sequence process for bringing the potential of the pixel electrode and the potential of the common electrode closer to each other is executed for a time corresponding to the acquired temperature,
The higher the temperature, the longer the time for performing the off-sequence process.
A control method for an electro-optical device.

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