JP2008102223A - Light emission period controlling device, self-luminous display device, electronic equipment and computer program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve such a problem that complicated signal processing is generally supposed to be necessary to suppress image persistence. <P>SOLUTION: A signal having a blunt rising waveform is supplied as a light emission period control signal to regulate a light emission period in a frame period. By inputting a light emission period control signal having a blunt rising waveform, the light emission period of a more degraded self-luminous element can be reduced compared to a less degraded self-luminous element. Thereby, difference in degradation quantity between the more degraded self-luminous element and the less degraded self-luminous element can be automatically reduced. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The invention described in this specification relates to a technique for suppressing or improving a burn-in phenomenon through light emission period control of a self-luminous display device. The invention proposed by the inventor has aspects as a light emission period control device, a self-luminous display device, an electronic device, and a computer program.

  The self-luminous display element has a characteristic that the light emission luminance decreases in proportion to the light emission amount and time. This decrease in light emission luminance is caused by deterioration in light emission characteristics. As the deterioration of the light emission characteristics proceeds, the luminance gradually decreases even under the same driving conditions, and the initial luminance cannot be maintained.

  By the way, the decrease in emission luminance generally does not proceed uniformly, and the emission characteristics deteriorate within the screen. This is because display contents are not uniform. The state in which the variation in luminance deterioration is visually recognized is called “burn-in phenomenon”.

Conventionally, in order to suppress the image sticking phenomenon, it has been considered most preferable to extend the light emitting lifetime of the light emitting element material.
However, even if the light emitting element material has a long light emission life, the occurrence of the image sticking phenomenon cannot be eliminated in principle, and only video signals that are likely to cause image sticking may be input continuously.

Therefore, a mechanism for delaying the occurrence of burn-in or making the generated burn-in inconspicuous has been studied.
JP 2003-228329 A

  However, existing techniques generally require a frame memory and complicated signal processing.

  Therefore, the inventor proposes a mechanism for supplying a signal having a dull rising waveform as a light emission period control signal that defines a light emission period within a frame period.

  The inventor supplies a signal having a dull rising waveform as a light emission period control signal to the self-light-emitting element, and introduces a mechanism in which the self-light-emitting element whose deterioration has progressed autonomously increases the time until the light emission starts. That is, the light emission time of the self-luminous element that has deteriorated is relatively shorter than the light emission time of the self-light-emitting element that has not deteriorated.

  This means that the deterioration rate of the self-luminous element that has progressed deterioration is lower than the deterioration rate of the self-luminous element that has little progress. Therefore, the continuation of the light emission control state acts in a direction to reduce the deterioration difference between the self light emitting elements, and the image sticking phenomenon is suppressed or improved.

Hereinafter, embodiments of the light emission period control device according to the invention will be described.
In addition, the well-known or well-known technique of the said technical field is applied to the part which is not illustrated or described in particular in this specification.
Moreover, the form example demonstrated below is one form example of invention, Comprising: It is not limited to these.

(A) Form example 1
In this embodiment, a case where the light emission period control device is mounted on an organic EL panel module will be described.

(A-1) Functional Configuration FIG. 1 shows a functional configuration example of the organic EL display panel module 1. The organic EL display panel module 1 includes a timing generator 3, a data line driver 5, a scan driver 7, a light emission period control driver 9, and an organic EL display panel 11.

  The timing generator 3 functions as a device that generates various timing signals necessary for screen display based on a timing signal included in the video signal. For example, a write pulse is generated.

  The data line driver 5 functions as a device that drives the data lines of the organic EL display panel 11. The data line driver 5 is composed of a digital / analog converter that converts the gradation value that specifies the light emission luminance of each pixel into an analog voltage value and executes an operation of supplying the analog voltage value.

  The scan driver 7 functions as a device that is used to select a horizontal line for which gradation values are to be written. The scan driver 7 generates a write pulse for selecting the gate lines wired in the horizontal direction in a line-sequential manner and supplies it to the organic EL display panel 11.

  The light emission period control driver 9 is a device that supplies a pulse signal having a dull rising waveform to the power supply line 33 (FIG. 3) dedicated to the organic EL element as the light emission period control signal VCP that defines the light emission period within the frame period.

  FIG. 2 shows a configuration example of the light emission period control driver 9 used in this embodiment. The light emission period control driver 9 includes a light emission period control pulse generator 21 and a low-pass filter 23. The light emission period control pulse generator 21 generates a rectangular pulse signal that defines a light emission period within one frame period.

  The low-pass filter 23 functions as a circuit that blunts the rise of the rectangular pulse signal. In the case of FIG. 2, the low-pass filter 23 includes a resistor R0 and a capacitor C0. Here, the resistance value R0 and the capacitance value C0 are set to a time constant τ sufficient to blunt the rising waveform. However, in an actual circuit, a circuit configuration that can obtain an optimum rising waveform is adopted.

  In the case of this embodiment, the light emission period control drivers 9 are arranged one by one on one horizontal line. The light emission period control signal VCP corresponding to each horizontal line is generated in synchronization with the horizontal synchronization signal. The light emission period control signal VCP corresponding to each horizontal line defines the light emission period of one frame period from the writing of the video signal to the corresponding horizontal line.

  The organic EL display panel 11 is a self-luminous display device in which organic EL elements are arranged in a matrix. The organic EL display panel 11 is for color display. Accordingly, one pixel (pixel) on the display is composed of pixels (subpixels) corresponding to the three colors of RGB.

(A-2) Configuration of Pixel Circuit FIG. 3 shows a connection relationship between the pixel circuit 31 formed at the intersection of the data line and the selection line and the peripheral circuit.
The pixel circuit 31 includes a switch element T1, a capacitor C1, a current supply element T2, and an organic EL element D1.

  Here, the switch element T1 is a transistor that executes the capturing (writing) of an analog voltage value applied through the data line. The write pulse is supplied through the write line at a timing synchronized with the horizontal synchronization signal HS.

  The capacitor C1 is a storage element that holds the analog voltage value written for each pixel for one frame period. By using the capacitor C1, even when data writing is executed by the line-sequential scanning driving method, the same light emission mode as that of the surface-sequential scanning driving method can be realized.

  The current supply element T2 is a transistor that supplies a drive current corresponding to the analog voltage value held in the capacitor C1 to the organic EL element D1. The supply and stop of the drive current by the current supply element T2 is controlled by the light emission period control signal VCP supplied to the power supply line 33. That is, the organic EL element D1 is turned on and off by the light emission period control signal VCP supplied to the power line 33.

  Specifically, the drive current flows to the organic EL element D1 only during a period in which a positive voltage is applied as the light emission period control signal VCP, and the supply of the drive current is stopped in other periods. That is, the organic EL element D1 is controlled to be lit only during a period in which a positive voltage is applied as the light emission period control signal VCP.

(A-3) Burn-in suppression effect by supplying light emission period control signal Hereinafter, it will be described that burn-in can be suppressed by supplying the light emission period control signal VCP having a dull rising waveform.
First, the light emission control operation in the case where the existing light emission period control signal VCP is supplied will be described with reference to FIG.

FIG. 4A shows a waveform example of a video signal applied to the data line. The video signal is supplied from the data line driver 5 as an analog voltage value for each horizontal line period.
FIG. 4B shows an input example of the write pulse WS for a certain horizontal line.
FIG. 4C shows the horizontal synchronization signal HS.

  4D and 4F are waveform examples of a general light emission period control signal VCP currently used. The light emission period control signal VCP shown in FIG. 4 has a rectangular shape with a steep rising waveform. Of course, if a very short time scale is found, there is a transition time until the waveform of the light emission period control signal VCP rises, but it is sufficiently short with respect to the horizontal line period.

4E and 4G show voltage changes generated between the electrodes of the organic EL element D1. As shown in FIGS. 4E and 4G, the rising waveform of the voltage V _EL generated between the electrodes of the organic EL element D1 becomes a dull waveform.

  4D and 4E show signal waveform relationships in a state where the deterioration of the organic EL element D1 has not progressed, and FIGS. 4F and 4G show the deterioration of the organic EL element D1. The signal waveform relationship in the advanced state is shown.

  As can be seen by comparing FIGS. 4E and 4G, even when the same light emission period control signal VCP is applied, the time for the deteriorated organic EL element D1 to reach the ON voltage becomes longer. That is, even when the same light emission period control signal VCP is given, the light emission time of the organic EL element D1 that has deteriorated is shorter than the light emission time of the organic EL element D1 that has not deteriorated.

This is because the IV characteristic of the organic EL element D1 changes as the deterioration progresses.
FIG. 5 shows the IV characteristics of the organic EL element D1. As indicated by a broken line in FIG. 5, in the organic EL element D1 that has deteriorated, the IV characteristic changes to a state tilted to the right as compared with the IV characteristic of the organic EL element D1 that has not deteriorated. . Therefore, even if the same current value i is supplied, in the organic EL element D1 that has deteriorated, the voltage V _EL increases by ΔV as compared to the case where the deterioration has not progressed.

This means that the resistance component of the organic EL element D1 increases as the deterioration progresses. That is, it means that the time constant τ increases as the deterioration progresses.
Therefore, the rise time and fall time of the voltage V _EL generated between the electrodes of the organic EL element D1 become longer as the deterioration progresses.

  Paying attention to these characteristics, the inventor generates the light emission period control signal VCP with the rising waveform intentionally blunted as described above and supplies it to the power supply line 23, and the deterioration of the organic EL element D1 and the deterioration. The rise time difference that occurs with the organic EL element D1 that has not advanced is expanded. That is, the light emission time difference is expanded.

The light emission control operation by the light emission period control signal VCP having a dull rising waveform will be described with reference to FIG.
FIG. 6A shows a waveform example of a video signal applied to the data line. The video signal is supplied from the data line driver 5 as an analog voltage value for each horizontal line period.
FIG. 6B shows an input example of the write pulse WS for a certain horizontal line.
FIG. 6C shows the horizontal synchronization signal HS.

  6D and 6F are waveform examples of the light emission period control signal VCP used in this embodiment. As shown in FIG. 6, a waveform in which the rising waveform and falling waveform of the light emission period control signal VCP are greatly dull is used.

FIGS. 6E and 6G show voltage changes that occur between the electrodes of the organic EL element D1. As shown in FIGS. 6E and 6G, the rising waveform and falling waveform of the voltage V _EL generated between the electrodes of the organic EL element D1 are duller than the waveform of the light emission period control signal VCP. .

  6D and 6E show signal waveform relationships in a state where the deterioration of the organic EL element D1 is not progressing, and FIGS. 6F and 6G show the deterioration of the organic EL element D1. The signal waveform relationship in the advanced state is shown.

  6E and 6G, even when the same light emission period control signal VCP is applied, the time for the deteriorated organic EL element D1 to reach the on-voltage V is increased. It takes longer than the time for the organic EL element D1 not to reach the ON voltage V.

  In the case of the first embodiment, the time difference until the ON voltage is reached is greatly increased as compared with the case where the rectangular light emission period control signal VCP (FIG. 4) is supplied. Therefore, even in the case of controlling with the same light emission period control signal VCP at the same drive timing, the light emission period difference between the pixels can be increased depending on the progress of deterioration.

Incidentally, as described above, the progress of the deterioration of the organic EL element D1 is proportional to the light emission time. Accordingly, the organic EL element D1 that has progressed deterioration acts to shorten the light emission time, and the organic EL element D1 that progresses less deterioration acts to increase the light emission time.
As a result, this light emission period difference exhibits an effect of autonomously reducing the deterioration amount difference between the organic EL elements D1.

  FIG. 7 shows how the image sticking phenomenon is suppressed. FIG. 7 is a diagram showing the progress of deterioration of a certain two pixels by the transition of light emission luminance. The transition diagram of the light emission luminance corresponding to each pixel represents the light emission luminance when 100% luminance is input at each time point. In FIG. 7, it is assumed that the existing light emission period control signal VCP (FIG. 4) is given until time T2.

In the case of FIG. 7, the deterioration of the two pixels proceeds in the same state until time T1. However, a difference in the degree of progress of deterioration occurs depending on the light emission state between time T1 and time T2, and a large luminance difference occurs at time T2.
The dotted line shown in FIG. 7 shows the transition of light emission luminance when the supply of the existing light emission period control signal VCP continues until time T3. As indicated by the dotted line, the luminance difference between the pixels becomes larger and the burn-in phenomenon is perceived on the screen.

  However, as shown by the solid line in FIG. 7, when the light emission period control signal VCP having a dull rising waveform is supplied, a pixel that has not deteriorated more than a pixel that has deteriorated has the same light emission condition. Since the deterioration further proceeds, the luminance difference between the pixels changes in the direction of reduction. That is, it means that the burn-in phenomenon can be suppressed or improved.

(A-4) Effect As described above, by supplying the light emission period control signal VCP having a dull waveform to the power supply line 33 dedicated to the organic EL element, the light emission time can be reduced according to the degree of deterioration of the organic EL element D1. It can be optimized autonomously. That is, the light emission time of the organic EL element D1 in which deterioration has progressed can be shortened compared to the light emission time of the organic EL element D1 in which deterioration has not progressed.

As a result, it is possible to control in a direction to shorten the deterioration amount difference between the organic EL elements D1 without requiring any complicated signal processing.
In the case of this embodiment, the light emission period control signal VCP having a dull waveform rising from the beginning of use of the organic EL panel module 1 is supplied. Therefore, it is difficult to enlarge the difference in deterioration amount between pixels until the burn-in phenomenon is perceived. That is, the occurrence of the image sticking phenomenon can be suppressed.

  Further, the organic EL display panel module 1 shown in the embodiment can be realized only by adding the required number of low-pass filters 23 to the existing panel structure. The circuit area of these low-pass filters 23 is very small, and the existing panel structure can be used almost as it is.

That is, no layout change or mounting space change is required. For this reason, it is advantageous also in terms of manufacturing cost.
For example, even when the screen size increases, the calculation amount and system scale do not increase. Further, for example, even when mounted on a portable electronic device having a small screen size, there is no significant change in the mounting space, which is advantageous for mounting.

(B) Other embodiment examples (B-1) Other light emission period control signal examples In the above-described embodiment example 1, the case where the power supply line 33 dedicated to the organic EL element is driven by the light emission period control signal VCP has been described.
However, the light emission period control signal can be realized as a drive signal (duty pulse signal DS) of the light emission period control element T3 connected in series with the organic EL element D1.

  FIG. 8 shows a configuration example of the pixel circuit 41 corresponding to this case. In the case of FIG. 8, a constant power supply voltage is always supplied to the power supply line 43. Further, the light emission period control element T3 is connected between the power supply line 43 and the current supply element T2. The light emission period control element T3 can also be connected between the current supply element T2 and the organic EL element D1. In the case of FIG. 8, the light emission period control element T3 is composed of an N-channel FET.

The light emission control operation by the light emission period control signal DS will be described with reference to FIG.
FIG. 9A shows a waveform example of a video signal applied to the data line. The video signal is supplied from the data line driver 5 as an analog voltage value for each horizontal line period.
FIG. 9B shows an input example of the write pulse WS for a certain horizontal line.
FIG. 9C shows the horizontal synchronization signal HS.

FIGS. 9D and 9F are waveform examples of the light emission period control signal DS used in this embodiment. Also in this case, the rising waveform of the light emission period control signal DS uses a greatly dull waveform.
FIGS. 9E and 9G show voltage changes generated between the electrodes of the organic EL element D1. As shown in FIGS. 9E and 9G, the rising waveform of the voltage V _EL generated between the electrodes of the organic EL element D1 becomes a waveform duller than the waveform of the light emission period control signal DS.

  9D and 9E show signal waveform relationships in a state where the deterioration of the organic EL element D1 has not progressed, and FIGS. 9F and 9G show the deterioration of the organic EL element D1. The signal waveform relationship in the advanced state is shown.

As can be seen by comparing FIGS. 9E and 9G, even when the same light emission period control signal DS is applied, the time for the deteriorated organic EL element D1 to reach the on-voltage does not progress. It takes longer than the time for the organic EL element D1 to reach the ON voltage.
The relationship of the on-voltage is the same as that described in the first embodiment. That is, as in Embodiment 1, it is possible to autonomously reduce the deterioration amount difference between pixels and suppress or improve the occurrence of burn-in.

(B-2) Other Pixel Circuit Example In the case of the above-described embodiment 1, one electrode of the capacitor C1 is connected to the connection midpoint of the switch element T1 and the current supply element T2, and the other electrode is connected to the power supply line. Explained the case.
However, as shown in FIG. 8, the structure of the pixel circuit is not limited to this.

  For example, as in the pixel circuit 51 shown in FIG. 10, one electrode of the capacitor C1 is connected to a connection midpoint between the switch element T1 and the current supply element T2, and the other electrode is connected between the current supply element T2 and the organic EL element D1. You may connect to the midpoint of connection.

(B-3) Supply Range of Light-Emitting Period Control Signal In the above-described first embodiment, the case where the light-emitting period control signal having a dull rising waveform is supplied to all horizontal lines has been described.
However, a light emission period control signal having a dull rising waveform may be supplied only for a part of the display range where burn-in easily occurs.

  FIG. 11 shows a supply example. FIG. 11 shows an example in which an emission period control signal having a dull rising waveform is supplied only to the display range in the upper part of the screen where the high-intensity fixed pattern is displayed like the current time.

  However, FIG. 11 is an example. For example, depending on the display contents, there may be other display areas where burn-in is likely to occur. Accordingly, it is desirable to freely change the supply range of the light emission period control signal having a dull rising waveform in accordance with the usage mode.

(B-4) Other Setting Examples of Light-Emitting Period In Embodiment 1 described above, the case where one light-emitting period is set within one frame period has been described.
However, as shown in FIG. 12C, a plurality of light emission periods may be set within one frame period.

FIG. 12A shows a waveform example of a video signal applied to the data line. FIG. 12B shows an input example of the write pulse WS for a certain horizontal line. FIG. 12D is an example of a voltage change generated between the electrodes of the organic EL element D1.
If a plurality of light emission periods are set in one frame, the number of rises is also multiple.

  That is, the effect of shortening the light emission period is expanded to a plurality of times in the case of the first embodiment. Therefore, the difference in the light emission time corresponding to the degree of progress of deterioration is further expanded, and the burn-in suppression effect can be enhanced.

(B-5) Another Configuration Example of Light-Emitting Period Control Driver In the above-described first embodiment, the light-emission period control driver 9 is composed of a light-emission period control pulse generator 21 and a low-pass filter 23 as shown in FIG. Explained the case.
However, the light emission period control signal having a dull rising waveform can be realized by other circuit configurations.

  FIG. 13 shows another configuration example of the light emission period control driver 9. As shown in FIG. 14, the light emission period control driver 9 shown in FIG. 13 generates a light emission period control signal with a slow rise by sequentially turning on the transistors T11 to T13. Note that the timing for turning on the power supply voltages V1 to V3 and each transistor is selected according to the dullness of the rising waveform to be realized.

Even if the transistors T11 to T13 are controlled to be turned on, a certain time is actually required until the charge is accumulated in the capacitor C2, so that the rising waveform of the light emission period control signal gradually increases.
In the case of this circuit configuration, the timing for turning on the transistors T11 to T13 can be realized through control by a computer program. In the case of a computer program, the shape of the rising waveform can be optimized by adjusting the timing of on-control.

  In Embodiment 1 described above, the case where the low-pass filter 23 is arranged to blunt the rising waveform of the rectangular pulse signal has been described. However, the low-pass filter is configured equivalently to the transmission path of the light emission period control signal. If the output stage to be used is used in the light emission period control pulse generator 21, the light emission period control signal having the same rising waveform can be generated.

(B-6) Variable control of rising waveform according to deterioration amount difference In the first embodiment, the case where the same signal waveform is basically used from the start of use has been described.
However, the rising waveform of the light emission period control signal may be changed according to the state of the deterioration amount difference that causes the burn-in phenomenon to be perceived.

FIG. 15 shows another configuration example of the organic EL display panel module 1. The organic EL display panel module 1 includes a deterioration amount difference detection unit 61, a light emission period control driver 9, and an organic EL display panel 11.
The deterioration amount difference detection unit 61 is a processing device that detects a deterioration amount difference between pixels based on a video signal. A known circuit configuration is applied to the deterioration amount difference detection unit 61.

For example, the deterioration amount may be calculated for each pixel, and the difference between the maximum value and the minimum value of the deterioration amount may be detected as the deterioration amount difference. Further, for example, the deterioration amount difference of each pixel may be calculated on the basis of the screen average value of the input video signal, and the maximum value of the deterioration amount difference may be detected.
The deterioration amount difference detection unit 61 compares a plurality of determination thresholds with the detected deterioration amount difference, and outputs a signal waveform change signal based on the comparison result.

  FIG. 16 shows a configuration example of the low-pass filter 23 suitable for this embodiment. The low pass filter 23 constitutes the light emission period control driver 9 together with the light emission period control pulse generator 21.

  The low pass filter 23 shown in FIG. 16 includes transistors T11 to T13 that are turned on / off based on a signal waveform change signal, and capacitors C11 to C13 corresponding to the transistors. Only one transistor T11 to T13 may be ON-controlled at the same time, or a plurality of transistors T11-T13 may be ON-controlled at the same time.

In any case, the capacitance value is changed by turning on the transistors T11 to T13, and the time constant τ is varied. Basically, the control is performed so that the rising waveform becomes duller as the deterioration amount difference becomes larger (so that the time constant τ becomes larger).
FIG. 17 shows an example of changing the signal waveform. As shown in FIG. 17, it can be seen that the rising waveform becomes dull at a certain point in time.

  When the deterioration amount difference is reduced, control is performed so that the rising waveform becomes duller each time a smaller determination threshold is exceeded.

(B-7) Rise Waveform Variable Control According to Use Time In the first embodiment, the case where the same signal waveform is basically used from the start of use has been described.
However, the rising waveform of the light emission period control signal may be changed according to the usage time.

FIG. 18 shows another configuration example of the organic EL display panel module 1. The organic EL display panel module 1 includes a use time timer 71, a light emission period control driver 9, and an organic EL display panel 11.
The usage time timer 71 is a processing device that measures the usage time of the organic EL display panel module 1. The usage time timer 71 measures, for example, a period during which the power button is on.

The usage time timer 71 compares a plurality of determination threshold values with the count value of the timer, and outputs a signal waveform change signal based on the comparison result.
The light emission period control driver 9 here can also employ the configuration shown in FIGS.

  In FIG. 19, an existing light emission period control signal (rectangular pulse signal) is used within a certain period from the start of use, and the light emission period control signal having a dull waveform after the timer count value exceeds a certain determination threshold. A control example in the case of using is shown.

However, the light emission period control signal having a dull rising waveform from the beginning may be used to increase the dullness of the rising waveform according to the usage time.
When a plurality of determination threshold values are used, control may be performed so that the degree of dullness of the rising waveform of the light emission period control signal gradually increases every time a larger determination threshold value is exceeded.

(B-8) Other Mounting Examples In the above-described Embodiment 1, the case where the light emission period control driver 7 is mounted on the organic EL display panel module 1 (self-luminous display device) has been described.
However, the light emission period control driver 9 can be mounted on various electronic devices equipped with a self-luminous display device.

FIG. 20 shows a functional configuration example of the electronic device 81. The electronic device 81 includes a light emission period control driver 9, an organic EL display panel 11, and a signal processing unit 83. The processing content executed by the signal processing unit 83 differs depending on the electronic device 81.
As this type of electronic device 81, for example, a broadcast wave receiving device, an audio device, a communication device, an imaging device, an information processing device, and other devices are assumed.

For example, the product form of the broadcast wave receiver is assumed to be a television program receiver, a radio program receiver, a portable electronic device equipped with a broadcast wave reception function, or the like.
Further, for example, portable music equipment, mobile phones, and the like are assumed as product forms of audio devices.

Further, for example, as a product form of the communication device, a stationary phone, a mobile phone, a portable electronic device having a communication function, and the like are assumed.
Further, for example, as a product form of the imaging device, a digital camera, a video camera, a portable electronic device equipped with an imaging function, and the like are assumed.

  Further, for example, a game machine, an electronic book, an electronic dictionary, a computer, a measuring device, and the like are assumed as the product form of the information processing apparatus.

(B-9) Other Display Device Examples In Embodiment 1 described above, the case where the display device is the organic EL display panel module 1 has been described.
However, the display device can also be applied to other EL displays. For example, the present invention can be applied to an inorganic EL display device and a display device in which LEDs are arranged. The display device may be an FED display device, a PDP display device, or other self-luminous display device.

(B-10) Control Device Configuration In the above description, the case where the light emission period control signal VCP or DS is generated in hardware has been described.
However, the light emission period control signal VCP or DS may be generated by software processing or a combination of hardware and software.

(B-11) Others Various modifications can be considered for the above-described embodiments within the scope of the gist of the invention. Various modifications and applications created or combined based on the description of the present specification are also conceivable.

It is a figure which shows the function structural example of an organic electroluminescence display panel module. It is a figure which shows the function structural example of the light emission period control driver. It is a figure explaining the structural example of a pixel circuit. It is a figure explaining the relationship between the existing light emission period control signal and the voltage generate | occur | produced between the electrodes of an organic EL element. It is a figure which shows the change of the IV characteristic accompanying deterioration of an organic EL element. It is a figure explaining the relationship between the light emission period control signal with which the rising waveform dulled, and the voltage generate | occur | produced between the electrodes of an organic EL element. It is a figure explaining the inhibitory effect of the image sticking phenomenon. It is a figure explaining the other structural example of a pixel circuit. It is a figure explaining the other relationship of the light emission period control signal with which the rising waveform dulled, and the voltage generate | occur | produced between the electrodes of an organic EL element. It is a figure explaining the other structural example of a pixel circuit. It is a figure which shows the example of the supply range of a light emission period control signal. It is a figure which shows the other example of a setting of light emission period. It is a figure which shows the other structural example of the light emission period control driver. It is a figure which shows the example of a generation | occurrence | production of the light emission period control signal with a dull rise. It is a figure which shows the example of an apparatus which can vary a rising waveform according to a degradation amount difference. It is a figure which shows the structural example of a low-pass filter of a time constant variable type. It is a figure explaining the change of the rising waveform according to a degradation amount difference. It is a figure which shows the example of an apparatus which can vary a rising waveform according to use time. It is a figure explaining the change of the rising waveform according to use time. It is a figure explaining the example of mounting to an electronic device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic EL panel module 9 Light emission period control driver 21 Light emission period control pulse generator 23 Low pass filter 61 Degradation amount difference detection part 71 Usage time timer

Claims (14)

A light emission period control device, characterized in that a signal with a dull rising waveform is supplied as a light emission period control signal for defining a light emission period within a frame period. In the light emission period control device according to claim 1,
The light emission period control device is characterized in that the light emission period control signal is a drive signal of a transistor connected in series with the self light emitting element. In the light emission period control device according to claim 1,
The light emission period control signal is a drive signal for a power supply line connected to a self light emitting element. The light emission period control device according to claim 1,
A pulse generator for generating a rectangular pulse signal with a sharp rising waveform;
A light emission period control device comprising: a low pass filter that generates the light emission period control signal from the pulse signal. The light emission period control device according to claim 1,
A light emission time control device comprising an output stage that constitutes a low-pass filter equivalent to a transmission path of the light emission period control signal. The light emission time control device according to claim 1,
Until the usage time of the self-luminous display device exceeds the determination threshold, supply a light emission period control signal with a short rise time,
A light emission time control device that supplies a light emission period control signal having a dull waveform after a usage time of a self-luminous display device exceeds a determination threshold. The light emission time control device according to claim 6,
A light emission time control device, characterized in that control is performed so that the dullness of the rising waveform gradually increases every time the use time exceeds a larger determination threshold. The light emission time control device according to claim 1,
A light emission time control device, characterized in that control is performed so that the dullness of the rising waveform gradually increases with the passage of time of use of the self light emitting display device. The light emission time control device according to claim 1,
Until the detected deterioration amount difference exceeds the determination threshold, a light emission period control signal with a short rise time is supplied,
A light emission time control device characterized by supplying a light emission period control signal having a dull rising waveform after the detected deterioration amount difference exceeds a determination threshold. The light emission time control device according to claim 9,
Each time the deterioration amount difference exceeds a larger determination threshold, the dullness of the rising waveform is controlled to be gradually increased. The light emission time control device according to claim 1,
The light emission time control device, characterized in that the light emission period control signal having a dull rising waveform is supplied only to a specific region of the self light emitting display device. A display panel in which self-luminous elements are arranged in a matrix;
A self-luminous display device comprising: a light emission period control unit that supplies a signal having a dull waveform as a light emission period control signal that defines a light emission period within a frame period of the display panel. A display panel in which self-luminous elements are arranged in a matrix;
A light emission period control unit that supplies a signal with a dull rising waveform as a light emission period control signal that defines a light emission period within a frame period of the display panel;
An electronic device comprising: a signal processing unit for information displayed on the display panel. A computer program for causing a computer to execute a process of supplying a self-luminous display device with a light emission period control signal that defines a light emission period within a frame period and has a dull waveform.

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