KR20020025775A - Method of driving electrooptic apparatus, electrooptic apparatus, and electronic equipment - Google Patents

Abstract

PURPOSE: A driving method for electro-optical device, electro-optical device and electronic apparatus are provided to implement a gray-scale display of an electro-optical device according to a time ratio gray-scale method without providing reset lines. CONSTITUTION: A first scanning signal SS(S1) is supplied to the first scanning line (S1). A second scanning signal SS(S2) is supplied to the second scanning line(S2). A third scanning signal SS(S3) is supplied to the third scanning line(S3). A first data signal DS(D1) is supplied to the first data line (D1). A second data signal DS(D2) is supplied to the second data line (D2). A third data signal DS(D3) is supplied to the third data line (D3). The switching transistor(ST11), the driving transistor(D11) and the reset transistor(RT11) are n-type, p-type and p-type, respectively. Accordingly, a high-potential scanning signal serves as an on-signal for causing the switching signal to enter the conducting state. Then, a low-potential set signal is supplied in accordance with the on-signal for the switching transistor. According to this setting step, the driving transistor enters the conducting state so as to cause the luminescent element to emit light. In contrast, the low-potential scanning signal serves as an on-signal for the reset transistor. According to this resetting step, a high potential is applied to the p-type driving transistor from the power line via the reset transistor so as to cause the driving transistor to enter the non-conducting state. Thus, the luminescence element enters the non-luminescence state.

Description

METHOD OF DRIVING ELECTROOPTIC APPARATUS, ELECTROOPTIC APPARATUS, AND ELECTRONIC EQUIPMENT}

The present invention relates to a method of driving an organic electro luminescence display device and a method and method for driving an electro-optical device most suitable for a display device such as an organic electro luminescence display device, and these electro-optical devices. An electronic device having a device.

An organic electroluminescent display device using an organic material as a light emitting material of a light emitting element is excellent in optical viewing angle, and is thinner, lighter in weight, smaller in size, and lower in power consumption. It has recently been noted as having the potential to adequately respond to requests from the market.

Unlike conventional liquid crystal display devices, the organic electroluminescent display device needs to control the light emitting state of the light emitting device by electric current. One of such methods is the Conductance Contro1 method (T. Shimoda, M. Kimura, et. al., Proc. Asia Display 98, 217, M. Kimura, et al., IEEE Trans.Elec. Dev. 46, 2282 (1999), M. Kimura, et al., Proc.IDW 99, 171, M. Kimura, et al., Dig. AM-LCD 2000, to be published). This method is a method of analoguely controlling the light emitting state of a light emitting element by a current value, and is specifically implemented by changing the potential applied to the gate electrode of a driving transistor which is involved in driving a light emitting element. However, in the case of using a thin film transistor which is likely to cause variations in current characteristics, the difference in current characteristics of each transistor may be directly reflected as the light emission state nonuniformity of the light emitting element.

Thus, area gradation method (M. Kimura, et al., Proc. Euro Display '99 Late-News Papers, 71, JP 11-073158, M. Kimura, et al., Proc. IDW 99 , 171, M. Kimura, et al., J. SID, to be published, M. Kimura, et al., Dig. AM-LCD 2000, to be published. Unlike the Conductance Contro1 method described above, the area gradation method is a method of controlling the light emission state of a light emitting element without using the light emission state of intermediate luminance. That is, the pixels arranged in a matrix form are divided into a plurality of sub pixels, and either one of a complete light emitting state or a completely non-light emitting state of a light emitting element included in these sub pixels is selected, and a plurality of sub pixels are selected. The gray scale display is performed by changing the total area of the sub-pixels in the complete light emission state among the pixels. In the area gray scale method, it is not necessary to set an intermediate current value corresponding to the light emission state of the intermediate luminance, so that the influence of the current characteristics of the transistor for driving the light emitting element is reduced, thereby improving the uniformity of the image quality. However, this method has a problem that the pixel structure is complicated because the number of gray scales is limited by the number of sub pixels, and in order to further increase the number of gray scales, the pixels need to be divided into more sub pixels.

In this regard, time gradation method (M. Kimura, et al., Proc. IDW 99, 171, M. Kimura, et al., Dig. AM-LCD 2000, to be published, M. Mizukami, et al., Dig SID 2000, 912, K. Inukai, et al., Dig. SID 2000, 924). The time gradation method is a method of obtaining a gradation by changing the period in which the light emitting element is in a complete light emission state in one frame. Therefore, it is not necessary to provide a large number of sub pixels in order to increase the number of gradations like the area gradation method, and it is also possible to use the area gradation method in combination, so that it is expected as a promising method for digitally displaying gradations. It is becoming.

However, `` K. Inukai, et al., Dig. SID (Sim 2000, 924), a time gray scale method called SES (Simultaneous-Erasing-Scan), requires a reset line in addition to the scan line, thereby reducing the light emitting area.

Accordingly, a first object of the present invention is to provide a method for obtaining a gradation of an electro-optical device without providing a reset line, and in particular, a time gradation method for gradation of an electro-optical device such as an organic electroluminescent display device. Is to provide a way to get by. It is also a second object to provide an electro-optical device driven by this driving method.

1 shows a pixel equivalent circuit of an electro-optical device according to an embodiment of the invention.

2 illustrates a pixel arrangement of an electro-optical device according to an embodiment of the present invention.

3 illustrates a method of driving an electro-optical device according to an embodiment of the present invention.

4 is a diagram showing current characteristics of a light emitting device according to an embodiment of the present invention;

5 shows a part of a manufacturing process of an electro-optical device according to an embodiment of the present invention.

FIG. 6 shows a part of a manufacturing process of an electro-optical device according to an embodiment of the present invention. FIG.

Fig. 7 is a diagram showing an example in which the electro-optical device according to one embodiment of the present invention is applied to a mobile personal computer.

8 is a diagram showing an example in the case where an electro-optical device according to an embodiment of the present invention is applied to a display portion of a cellular phone.

FIG. 9 illustrates a perspective view of a digital still camera in which an electro-optical device according to an embodiment of the present invention is applied to a finder portion. FIG.

* Explanation of symbols for main parts of the drawings

V: power line

A: cathode

L11: light emitting element

DT11: Driving Transistor

ST11: Switching Transistor

C11: Capacitor

S1: first scanning line

S2: second scanning line

S3: third scanning line

D1: first data line

D2: second data line

SS (S1): Scanning signal of the first scanning line

SS (S2): scan signal of the second scan line

SS (S3): Scanning signal of the third scanning line

DS (D1): data signal of the first data line

DS (D2): data signal of the second data line

DS (D3): data signal of the third data line

E1 (11): first light emission period of the pixel 11

E2 (11): second emission period of the pixel 11

E3 (11): third light emission period of the pixel 11

E1 (21): First light emission period of the pixel 21

E2 (21): Second emission period of the pixel 21

E3 (21): Third light emission period of the pixel 21

E1 (31): First light emission period of the pixel 31

E2 (31): Second emission period of the pixel 31

E3 (31): Third light emission period of the pixel 31

Vsig: Control Potential

IIep: Current value

1: glass substrate

2: polycrystalline silicon layer

3: gate insulating film

4: gate electrode

5a: p-type transistor

5b: n-type transistor

6: first interlayer insulating film

7: source electrode and drain electrode

8: second interlayer insulating film

9: pixel electrode

10: adhesion layer

11: interlayer

12: hole injection layer

13: light emitting layer

14: cathode

15: sealing layer

In order to achieve the first object, a driving method of the first electro-optical device of the present invention includes an electro-optical element, a driving transistor for driving the electro-optical element, and a driving transistor corresponding to the intersection of the scan line and the data line. A driving method of an electro-optical device having a switching transistor for controlling a switching transistor and a reset transistor for resetting the driving transistor in a non-conductive state, the method comprising: driving an on-signal for turning the switching transistor on; A set step of supplying a set signal for supplying the switching transistor via the data signal and the switching transistor to the driving transistor via the data line and the switching transistor in response to a period during which the on signal is supplied; The reset transistor is turned on. And a reset step of resetting the driving transistor to a non-conductive state by supplying an ON signal to the reset transistor via the scan line. That is, by supplying the ON signal of the switching transistor and the ON signal of the reset transistor via the same scan line, the light emission period can be appropriately set without providing the reset line. Here, the electro-optical element and the electro-optical device mean an element and a device in which the light emission state or the optical characteristic is controlled electrically, respectively. As a specific example of an electro-optical device, display apparatuses, such as a light emitting display device, a liquid crystal display device, an electrophoretic display device, are mentioned, for example.

In addition, in the present specification, "a set signal for supplying an on signal to the switching transistor via the scanning line, and correspondingly selecting the conduction or non-conduction of the driving transistor to correspond to the driving transistor via the data line and the switching transistor. And a step of resetting the driving transistor to a non-conductive state by supplying an on signal for turning on the reset transistor to the reset transistor via the scan line. "Is defined as a" reset step. "

The method for driving a second electro-optical device of the present invention is the method for driving the electro-optical device, wherein the electro-optical device further includes a power supply line for supplying current to the electro-optical element via the driving transistor. One end of the reset transistor is connected to this power supply line.

The driving method of the third electro-optical device of the present invention is the driving method of the electro-optical device, wherein the conductive type of the switching transistor and the conductive type of the reset transistor are different from each other. This means, for example, that the reset transistor is p-type when the switching transistor is n-type and the reset transistor is n-type when the switching transistor is p-type. Thereby, the switching transistor and the reset transistor can be complementarily operated by appropriately selecting the high potential and low potential signals.

In the method of driving the fourth electro-optical device of the present invention, in the method of driving the electro-optical device, the conductive types of the switching transistor, the driving transistor, and the reset transistor are n-type, p-type, and p, respectively. It is characterized by being a type. That is, since the switching transistor can be turned on by supplying the high potential scan signal and the reset transistor can be turned on by supplying the low potential scan signal, the switching transistor and the reset transistor can be complementarily operated. Can be.

In the method for driving a fifth electro-optical device of the present invention, in the method for driving an electro-optical device, the voltage value VS corresponding to an on signal for turning on the switching transistor and the reset transistor are turned on. The voltage value VR corresponding to the on signal and the voltage value VO corresponding to the off signal for turning off the switching transistor and the reset transistor together satisfy the relational expression of VS> VO> VR.

The driving method of the sixth electro-optical device of the present invention is characterized in that in the driving method of the electro-optical device described above, a relational expression of -VsV VR and VO = 0V (volts) is satisfied. By the driving method of the electro-optical device according to claims 5 and 6 of the claims, the on-off operation of the switching transistor and the on-off operation of the reset transistor are merely set by setting three voltage values of VS, VO, and VR. OFF operation can be performed.

In the driving method of the seventh electro-optical device of the present invention, in the driving method of the electro-optical device, the period for turning on the switching transistor is to turn off the reset transistor, and to reset the reset transistor. The period for turning on is characterized in that the switching transistor is turned off. Thereby, the state selection of the electro-optical element and the period for maintaining the selected state can be clearly set.

The driving method of the eighth electro-optical device of the present invention is the driving method of the electro-optical device, characterized in that the gradation is obtained by setting a time interval between the set step and the reset step. That is, since the time interval between the set step and the reset step corresponds to the holding period of the selected state of the electro-optical element, the gradation can be obtained by setting this time interval appropriately.

A driving method of the ninth electro-optical device of the present invention is the driving method of the electro-optical device described above, wherein obtaining a gray scale by repeating the set-reset operation defined by the set step and the reset step a plurality of times. It features. Since the state of the electro-optical element is selected in the set step, and the holding period of the selected state is determined in the reset step, it is possible to obtain multiple gradations by repeating this set-reset operation a plurality of times. Become. Further, in the present specification, the set-reset operation is defined as an operation defined by the set step and the reset step defined above.

In the driving method of the tenth electro-optical device of the present invention, in the driving method of the electro-optical device, the time interval between the set step and the reset step in the set-reset operation repeated a plurality of times is respectively. It is characterized by being different.

In the method for driving an eleventh electro-optical device of the present invention, in the method for driving an electro-optical device, the time interval between the set step and the reset step of the set-reset operation repeated a plurality of times is different. And the ratio of these time intervals is approximately 1: 2:... Based on the minimum time interval among the time intervals. It is characterized in that it is set to be: ²ⁿ (n is an integer of 1 or more). For example, when performing two set-reset operations in which the ratio of the time intervals is 1: 2, four gray scale displays of 0, 1, 2, and 3 are possible. On the other hand, when performing two set-reset operations in which the ratio of the time intervals is 1: 1, there are three gray levels of 0, 1, and 2. That is, in this method of driving the electro-optical device, the maximum number of gradations can be obtained by the minimum repetition of the set-reset operation. Further, the ratio of time intervals must be exactly 1: 2:... : 2 ⁿ (n is an integer of 1 or more) does not need to be accurate enough to cope with the required gradation accuracy.

The driving method of the twelfth electro-optical device of the present invention is the driving method of the electro-optical device, wherein the set signal determines the conduction state of the driving transistor instead of selecting the conduction or non-conduction of the driving transistor. Characterized in that the signal. This means that in addition to the two states of conduction and non-conduction of the driving transistor, an intermediate conduction state can be selected, and the set signal is a signal having three or more values set continuously or discretely. The supply can be realized. This driving method is an effective method for realizing a large number of gradations.

The drive method of a thirteenth electro-optical device of the present invention is the drive method of the electro-optical device, wherein the electro-optical element is an organic electroluminescent element. An organic electroluminescent element is a light emitting element which uses an organic substance as an electroluminescent material.

The first electro-optical device of the present invention is characterized by being driven by the driving method of the electro-optical device. That is, in this electro-optical device, by supplying the ON signal of the switching transistor and the ON signal of the reset transistor via the same scanning line, the state holding period of the electro-optical element selected by the set step is appropriately set without providing the reset line. Can be.

According to the second electro-optical device of the present invention, an electro-optical element, a driving transistor for driving the electro-optical element, a switching transistor for controlling the driving transistor, and the driving transistor are non-corresponding to the intersection of the scan line and the data line. An electro-optical device having a reset transistor for resetting to a conductive state, the electro-optical device comprising: generating a signal for turning on or off the switching transistor and the reset transistor, and in response to a signal for turning the switching transistor on; And at least one driving circuit for generating a signal for setting the driving transistor. Here, only one driving circuit generates a signal for turning on or off the switching transistor and the reset transistor, and generates a signal for setting the driving transistor in response to a signal for turning the switching transistor on. It is not necessarily necessary, and can also be performed by a plurality of drive circuits.

According to the third electro-optical device of the present invention, an electro-optical element, a driving transistor for driving the electro-optical element, a switching transistor for controlling the driving transistor, and the driving transistor are non-corresponding to the intersection of the scanning line and the data line. An electro-optical device having a reset transistor for resetting to a conductive state, comprising: a scan line driver for supplying a signal for turning on or off the switching transistor and the reset transistor to the scan line, and an operation of the scan line driver. And a data line driver for supplying a signal for setting the driving transistor to the data line.

According to the fourth electro-optical device of the present invention, an electro-optical element, a driving transistor for driving the electro-optical element, a switching transistor for controlling the driving transistor, and the driving transistor are non-corresponding to the intersection of the scan line and the data line. An electro-optical device having a reset transistor for resetting to a conductive state, comprising: an on signal for performing a set step of setting a display state of the electro-optical element, supplied to the switching transistor via the scanning line, and An on signal for performing a reset step of resetting the display state is supplied to the reset transistor via the scan line. In addition, the meaning of a "set step" and a "reset step" here is substantially the same meaning as the set step and reset step in Claim 1 of a claim, respectively.

The fifth electro-optical device of the present invention is the electro-optical device, wherein the electro-optical device further includes a power supply line for supplying current to the electro-optical element via the driving transistor, and one end of the reset transistor. It is characterized by being connected to this power supply line. Therefore, the first to fifth electro-optical devices of the present invention do not require a reset line for performing the time gradation method. Therefore, there is an advantage that a sufficient display area can be secured. In addition, when a larger number of gradations is required, combined use with the area gradation method is also possible if a sub-pixel is provided in the pixel of this electro-optical device.

The sixth electro-optical device of the present invention is the electro-optical device, wherein the electro-optical element is an organic electroluminescent element.

The first electronic device of the present invention is an electronic device in which the electro-optical device is mounted.

Hereinafter, preferred embodiments of the present invention will be described.

The basic circuit according to the embodiment of the present invention includes a polycrystalline silicon thin film transistor (low temperature poly-Si TFT) formed in a low temperature process of 600 degrees or less. The low-temperature poly-Si TFT can be formed on a large-area and inexpensive glass substrate, and a drive circuit can be built in the panel, which is suitable for manufacturing an electro-optical device such as a light emitting display. In addition, since the current supply capability is high even at a small size, the present invention is also suitable for high-precision current light emitting display elements. In addition to the low temperature poly-Si TFT, the present invention is also applicable to an electro-optical device driven by an amorphous silicon thin film transistor (a-Si TFT), a silicon-based transistor, or a so-called organic thin film transistor using an organic semiconductor.

1 shows a pixel equivalent circuit of the electro-optical device according to the embodiment of the present invention. In this embodiment, the scan line S1, the data line D1 and the power supply line V are formed, and corresponding to the intersection of the scan line S1 and the data line D1, the light emitting element L11 and the light emitting element ( A driving transistor DT11 for driving L11, a switching transistor ST11 for controlling the driving transistor DT11, a reset transistor RT11 for resetting the driving transistor DT11, and a capacitor C11. It is an electro-optical device provided with one end of the light emitting element L11 connected to the cathode A. Since the driving transistor DT11 is of p type, the conduction of the driving transistor DT11 is selected by the low potential data signal, and the light emitting element L11 is brought into a light emitting state. On the other hand, the non-conduction of the driving transistor DT11 is selected by the high potential data signal, and the light emitting element is in the non-light emitting state. In the pixel equivalent circuit shown in this figure, the switching transistor ST11, the driving transistor DT11, and the reset transistor RT11 are n-type, p-type, and p-type, respectively, but are not limited thereto.

2 is a diagram illustrating wiring and pixel arrangement of an electro-optical device according to an exemplary embodiment of the present invention. A plurality of scan lines S1, S2, ..., and a plurality of data lines D1, D2, ... form a pixel, and pixels are formed corresponding to the intersections of the scan lines and the data lines. For example, the pixel 11 is provided corresponding to the intersection of S1 and D1. The pixel basically includes a switching transistor ST11, a reset transistor RT11, a capacitor C11, a driving transistor DT11, and a light emitting element L11 as shown in FIG. It may also include a pixel. In addition, the power supply line V is abbreviate | omitted in this figure.

3 shows a method of driving an electro-optical device having the circuit and pixel arrangement shown in FIGS. 1 and 2 according to an embodiment of the invention. The first scan signal SS (S1) is supplied to the scan line S1, the second scan signal SS (S2) is supplied to the second scan line S2, and the third scan is supplied to the third scan line S3. The signal SS (S3) is supplied. The first data signal DS (D1) is supplied to the first data line D1, the second data signal DS (D2) is supplied to the second data line D2, and the third data line D3 is supplied. ) Is supplied with the third data signal DS (D3).

In the present embodiment, since the switching transistor ST11, the driving transistor DT11, and the reset transistor RT11 are n-type, p-type, and p-type, respectively, the high potential scan signal functions as an on signal of the switching transistor. The switching transistor is brought into a conductive state. In response to the ON signal of the switching transistor, the set step of supplying the low potential set signal as indicated by the hatched portion causes the driving transistor to be in a conductive state, and the light emitting element emits light. On the other hand, the low potential scan signal functions as an on signal of the reset transistor, and by this reset step, a high potential is applied to the p-type driving transistor from the power supply line through the reset transistor, and the driving transistor is in a non-conductive state. The light emitting element is in a non-light emitting state.

The light emission periods E1, E2, E3 of the light emitting element are defined by the time interval between the set step and the reset step. Here, the length ratio of the light emission periods E1, E2, E3 is set to be approximately 1: 2: 4, whereby eight gradations of 0, 1, 2, 3, 4, 5, 6, and 7 are obtained. . In addition, in this embodiment, although the time interval between the set step and the reset step is performed sequentially from the short set-reset operation, it is not necessary to first perform the set-reset operation with the short time interval, and sets having different time intervals are used. The order in which the reset operations are performed may be selected depending on the usage situation or specification. In addition, since the transistor or the light emitting element may need some time to respond to the signal, as shown in this figure, the start time and end time of the light emission period are respectively determined by the start time and the reset step of the set step. There may be a difference from the start time. In this figure, the period for supplying the ON signal of the switching transistor and the period for supplying the set signal are completely overlapped, but it may not necessarily be completely overlapped depending on the use situation or specification.

4 is a diagram illustrating current characteristics of a light emitting device according to an exemplary embodiment of the present invention. The horizontal axis represents the control potential Vsig applied to the gate electrode of the driving transistor, and the vertical axis represents the current value IIep in the organic electroluminescent device. Since the current value and the light emission luminance in the organic electroluminescent device are approximately in proportion to each other, the vertical axis may be considered to correspond to the light emission luminance. In the present embodiment, it is preferable to control the organic electroluminescent device in either a fully on state or a completely off state. Therefore, in the fully on state or the completely off state, since the current value IIep is almost constant even if the transistor characteristics fluctuate, the current value in the light emitting element hardly changes, and the light emission luminance is also substantially constant. Therefore, it becomes possible to realize image quality uniformity.

5 is a view showing a thin film transistor manufacturing process of the electro-optical device according to the embodiment of the present invention. First, amorphous silicon is formed on the glass substrate 1 by PECVD using SiH ₄ or LPCVD using Si ₂ H ₆ . Amorphous silicon is polycrystallized by laser irradiation or solid phase growth of an excimer laser or the like to form a polycrystalline silicon layer 2 (FIG. 5A). After patterning the polycrystalline silicon layer 2, the gate insulating film 3 is formed, and the gate electrode 4 is further formed (FIG. 5B). Impurities, such as phosphorus or boron, are injected into the polycrystalline silicon layer 2 in a self-aligned manner using the gate electrode 4 to form the MOS transistors 5a and 5b. Further, 5a and 5b are p-type driving transistors and n-type switching transistors, respectively. In addition, the reset transistor is omitted in FIG. After forming the first interlayer insulating film 6, the contact hole is opened, and a source electrode and a drain electrode 7 are further formed (FIG. 5C). Next, after forming the second interlayer insulating film 8, the contact hole is opened to further form a pixel electrode 9 made of ITO (Fig. 5 (d)).

6 is a view showing a pixel manufacturing process of the electro-optical device according to the embodiment of the present invention. First, the adhesion layer 10 is formed, and an opening is formed corresponding to the light emitting area. After the interlayer layer 11 is formed, an opening is formed (FIG. 6A). Next, the wettability of the substrate surface is controlled by performing plasma treatment such as oxygen plasma or CF ₄ plasma. Thereafter, the hole injection layer 12 and the light emitting layer 13 are spin-coated, a squeegee coating, a liquid phase process such as an inkjet process, or a vacuum process such as sputtering or vapor deposition. And the cathode 14 containing a metal such as aluminum is further formed. Finally, the sealing layer 15 is formed and the organic electroluminescent element is completed (FIG. 6B). The role of the adhesion layer 10 is to improve the adhesion between the substrate and the interlayer layer 11 and to obtain an accurate light emitting area. The role of the interlayer layer 11 is to keep the cathode 14 away from the gate electrode 4 or the source electrode and the drain electrode 7 to reduce the parasitic capacitance, and the hole injection layer 12 or the light emitting layer in the liquid phase process. In forming (13), the wettability of the surface is controlled to perform accurate patterning.

Next, some examples of the electronic apparatus to which the above-mentioned electro-optical device is applied will be described. 7 is a perspective view showing the configuration of a mobile personal computer to which the above-mentioned electro-optical device is applied. In FIG. 7, the personal computer 1100 is constituted by a main body portion 1104 having a keyboard 1102 and a display unit 1106, which display unit 1106 includes the electro-optical device 100 described above. Doing.

8 is a perspective view showing the configuration of a cellular phone in which the above-mentioned electro-optical device 100 is applied to the display unit. In FIG. 8, the cellular phone 1200 includes the above-described electro-optical device 100 together with the receiver 1204 and the talker 1206 in addition to the plurality of operation buttons 1202.

9 is a perspective view which shows the structure of the digital still camera which applied the above-mentioned electro-optical device 100 to the finder. 9 also briefly shows a connection with an external device. Here, the conventional camera is used to photograph the film by the optical image of the subject, while the digital still camera 1300 photoelectrically converts the optical image of the subject by an imaging device such as a charge coupled device (CCD) to capture an image signal. Create The electro-optical device 100 described above is provided on the back of the case 1302 in the digital still camera 1300, and is configured to display based on an image pickup signal by a CCD, and the electro-optical device 100 is a subject. It functions as a finder to display. Further, a light receiving unit 1304 including an optical lens, a CCD, or the like is provided on the observation side (back side in the drawing) of the case 1302.

When the photographer checks the subject image displayed on the electro-optical device 100 and presses the shutter button 1306, the CCD imaging signal at that time is transmitted and stored in the memory of the circuit board 1308. In this digital still camera 1300, a video signal output terminal 1312 and an input / output terminal 1314 for data communication are provided on the side surface of the case 1302. As shown in FIG. As shown in the figure, a television monitor 1430 is connected to the former video signal output terminal 1312 and a personal computer 1430 is connected to the latter data communication input / output terminal 1314 as necessary. In addition, the imaging signal stored in the memory of the circuit board 1308 by a predetermined operation is output to the television monitor 1430 or the personal computer 1440.

As the electronic apparatus to which the electro-optical device 100 of the present invention is applied, in addition to the personal computer of FIG. 7, the mobile phone of FIG. 8, and the digital still camera of FIG. 9, a liquid crystal television, a viewfinder type, and a monitor direct view type Video tape recorders, car navigation devices, portable handheld pagers, electronic organizers, calculators, word processors, workstations, video phones, POS terminals, and devices with touch panels. The above-described electro-optical device 100 can be applied as a display portion of these various electronic devices.

As described above, according to the present invention, gradation of an electro-optical device such as an organic electroluminescent display device can be obtained by a time gradation method without providing a reset line.

Claims (20)

Corresponding to the intersection of the scan line and the data line, the electro-optical element, a driving transistor for driving the electro-optical element, a switching transistor for controlling the driving transistor, and the driving transistor are in a non-conductive state. A driving method of an electro-optical device having a reset transistor to reset, A set signal for supplying an on signal for turning on the switching transistor to the switching transistor via the scan line and selecting conduction or non-conduction of the driving transistor in response to a period for supplying the on signal; A set step of supplying the driving transistor via a data line and the switching transistor; A reset step of resetting the driving transistor to a non-conductive state by supplying an on signal for turning on the reset transistor to the reset transistor via the scan line; Method of driving an electro-optical device comprising a. The method of claim 1, The electro-optical device further includes a power supply line for supplying current to the electro-optical element via the driving transistor, and one end of the reset transistor is connected to the power supply line. . The method according to claim 1 or 2, And a conductive type of the switching transistor and a conductive type of the reset transistor are different from each other. The method according to claim 1 or 2, And the conductive types of the switching transistor, the driving transistor, and the reset transistor are n-type, p-type, and p-type, respectively. The method of claim 4, wherein A voltage value VS corresponding to an on signal for turning on the switching transistor, a voltage value VR corresponding to an on signal for turning on the reset transistor, and the switching transistor and the reset transistor together in an off state. A drive method for an electro-optical device, wherein a voltage value VO corresponding to an off signal satisfies a relation of VS> VO> VR. The method of claim 5, A driving method for an electro-optical device, which satisfies a relation of VSVVR and VO = 0V (volts). The method according to claim 1 or 2, A period in which the switching transistor is in an on state, and a reset transistor in an off state, and a period in which the reset transistor is in an on state, turns the switching transistor in an off state. . The method according to claim 1 or 2, The gray level is obtained by setting a time interval between the set step and the reset step. The method according to claim 1 or 2, The gradation is obtained by repeating the set-reset operation defined by the set step and the reset step a plurality of times. The method of claim 9, And a time interval between the set step and the reset step in the set-reset operation repeated a plurality of times is different from each other. The method of claim 9, The time intervals between the set step and the reset step of the set-reset operation repeated a plurality of times are all different, and the ratio of these time intervals is approximately 1: 2 based on the minimum time interval of the time intervals. :… : 2 ⁿ (n is an integer of 1 or more), the driving method of the electro-optical device characterized by the above-mentioned. The method according to claim 1 or 2, And the set signal is a signal for determining a conduction state of the driving transistor, instead of selecting conduction or non-conduction of the driving transistor. The method according to claim 1 or 2, And said electro-optical element is an organic electroluminescent element. It is driven by the driving method of the electro-optical device as described in any one of Claims 1-13. The electro-optical device characterized by the above-mentioned. Corresponding to the intersection of the scan line and the data line, an electro-optical element, a driving transistor for driving the electro-optical element, a switching transistor for controlling the driving transistor, and a reset transistor for resetting the driving transistor in a non-conductive state are provided. Equipped with an electro-optical device, At least one driving circuit for generating a signal for turning on the switching transistor and the reset transistor in an on state or an off state and generating a signal for setting the driving transistor in response to a signal for turning the switching transistor on; Electro-optical device, characterized in that. Corresponding to the intersection of the scan line and the data line, an electro-optical element, a driving transistor for driving the electro-optical element, a switching transistor for controlling the driving transistor, and a reset transistor for resetting the driving transistor in a non-conductive state are provided. Equipped with an electro-optical device, A scan line driver for supplying a signal for turning on the switching transistor and the reset transistor to an on state or an off state to the scan line; And a data line driver for supplying a signal for setting the driving transistor to the data line in response to an operation of the scan line driver. Corresponding to the intersection of the scan line and the data line, an electro-optical element, a driving transistor for driving the electro-optical element, a switching transistor for controlling the driving transistor, and a reset transistor for resetting the driving transistor in a non-conductive state are provided. Equipped with an electro-optical device, An on signal for performing the set step of setting the electro-optical element is supplied to the switching transistor via the scanning line, and And an on signal for performing a reset step of resetting the electro-optical element is supplied to the reset transistor via the scan line. The method according to any one of claims 15 to 17, And the electro-optical device further comprises a power supply line for supplying current to the electro-optical element via the driving transistor, wherein one end of the reset transistor is connected to this power supply line. The method according to any one of claims 15 to 17, The electro-optical device is an organic electroluminescent device. An electronic device comprising the electro-optical device according to any one of claims 14 to 19 mounted thereon.