Abstract: A precharge voltage Vp is applied in period A. The precharge voltage Vp is generated by applying a constant current Iw to a pixel driving transistor of a display panel and using gate terminal voltage of the driving transistor which passes the constant current Iw. The gate terminal potential is held in memory. When displaying images on a display panel, the gate terminal potential is read out of memory, and used as the precharge voltage Vp after arithmetic processing. By the application of the precharge voltage Vp, a source signal line is charged and discharged quickly so that an almost target tone current will flow through the driving transistor. Furthermore, a more accurate program current is written into the pixel during period B.

Abstract: In order to charge and discharge parasitic capacitance of a source signal line sufficiently and program a predetermined current value into a pixel transistor, it is necessary to output a relatively large current from the source driver circuit. However, if such a large current is passed through the source signal line, the value of this current is programmed into the pixel, causing a larger than desired current to flow through an EL element. For example, if a 10 times larger current is used for programming, a 10 times larger current flows through the EL element, and thus the EL element illuminates 10 times more brightly. To obtain predetermined emission brightness, the time during which the current flows through the EL element can be reduced to 1/10 of one frame (1 F). This way, the parasitic capacitance of the source signal line can be charged and discharged sufficiently and the predetermined emission brightness can be obtained.

Abstract: To provide a drive method capable of maintaining gradation display performance regardless of screen display brightness. Reference numeral 491R denotes a regulator used to control reference current for red (R). By adjusting a reference current for R linearly, it is possible to linearly vary a current flowing through a transistor 472a which constitutes a current mirror with a transistor 471R. This changes a current flowing through a transistor 472b which has received a current-based delivery from the transistor 472a in a transistor group 521a. This in turn causes changes to a transistor 473a in a transistor group 521b which constitutes a current mirror with the transistor 472b, resulting in changes to a transistor 473b which has received a current-based delivery from the transistor 473a. Thus, since drive current of the unit transistor 484 changes, programming current can be changed linearly.

Abstract: In order to charge and discharge parasitic capacitance of a source signal line sufficiently and program a predetermined current value into a pixel transistor, it is necessary to output a relatively large current from the source driver circuit. However, if such a large current is passed through the source signal line, the value of this current is programmed into the pixel, causing a larger than desired current to flow through an EL element. For example, if a 10 times larger current is used for programming, a 10 times larger current flows through the EL element, and thus the EL element illuminates 10 times more brightly. To obtain predetermined emission brightness, the time during which the current flows through the EL element can be reduced to 1/10 of one frame (1 F). This way, the parasitic capacitance of the source signal line can be charged and discharged sufficiently and the predetermined emission brightness can be obtained.

Abstract: To provide a drive method capable of maintaining gradation display performance regardless of screen display brightness. Reference numeral 491R denotes a regulator used to control reference current for red (R). By adjusting a reference current for R linearly, it is possible to linearly vary a current flowing through a transistor 472a which constitutes a current mirror with a transistor 471R. This changes a current flowing through a transistor 472b which has received a current-based delivery from the transistor 472a in a transistor group 521a. This in turn causes changes to a transistor 473a in a transistor group 521b which constitutes a current mirror with the transistor 472b, resulting in changes to a transistor 473b which has received a current-based delivery from the transistor 473a. Thus, since drive current of the unit transistor 484 changes, programming current can be changed linearly.

Abstract: In order to charge and discharge parasitic capacitance of a source signal line sufficiently and program a predetermined current value into a pixel transistor, it is necessary to output a relatively large current from the source driver circuit. However, if such a large current is passed through the source signal line, the value of this current is programmed into the pixel, causing a larger than desired current to flow through an EL element. For example, if a 10 times larger current is used for programming, a 10 times larger current flows through the EL element, and thus the EL element illuminates 10 times more brightly. To obtain predetermined emission brightness, the time during which the current flows through the EL element can be reduced to 1/10 of one frame (1 F). This way, the parasitic capacitance of the source signal line can be charged and discharged sufficiently and the predetermined emission brightness can be obtained.

Abstract: A drive method of an EL display apparatus that includes a switching element that turns on and off a current path between a driver transistor and an EL element. The drive method aggregates image data input to the EL display apparatus, and determines a period to turn off the switching element according to an amount of the aggregate data. With the method, suppression of peak current and expansion of contrast and so on is realized.

Abstract: In a display panel, a dummy pulse of a predetermined voltage signal is superimposed on a data signal and the dummy pulse has an amplitude much larger than the amplitude of the data signal, and thus a signal waveform applied to a light modulation layer such as LC layer is changed to a high frequency wave. The applying position of the dummy pulse is varied according to each color of R, G and B, or varied according to frame or field. By performing a MLS drive with the dummy pulse superimposed on the data signal, the amplitude difference between the selection signal and the data signal can be reduced. Thus, a common driver IC and a segment driver IC can be formed as one semiconductor chip to be placed on one side, constructing a three side free type.

Abstract: An EL display device includes: a source driver circuit to output a video signal voltage; a gate driver circuit to select a pixel in a display screen; a first capacitor to maintain the video signal voltage; and a drive transistor to supply current to an EL element of a pixel. The video signal voltage is applied to the drive transistor to perform a predetermined operation, and written into the first capacitor. The video signal voltage maintained in the first capacitor is used to perform an offset cancel operation.

Abstract: A drive method of an EL display apparatus that includes a display screen in which pixels each of which includes an EL element are provided in a form of a matrix. The drive method includes: aggregating or processing by use of a histogram an image signal applied to the EL display apparatus, and controlling a current flowing in the display panel according to at least one of a result of the aggregating the image signal or a result of the processing by use of the histogram.

Abstract: The EL display apparatus according to this invention is provided with an EL light emitting element, a current driving device for driving the EL light emitting element by a current responsive to a source signal represented by a current, and a signal current source (634) for outputting the source signal in response to image signal to the current driving device via a source signal line, the EL display apparatus being further provided with a precharge voltage source (631) for outputting a predetermined voltage and a switching and connecting unit (636, 637) capable of selectively connecting either the signal current source or the precharge voltage source to the source signal line (638).

Abstract: A switch being turned off using an output open function of a power supply circuit, a cathode voltage Vss is not transmitted, an output terminal takes on a high impedance condition and, a probing being done into a pad of the cathode voltage Vss output terminal with a probe, an ammeter which measures a current is disposed between the probe 304 and an external power source Vsst, making an adjustment time cathode voltage Vsst equal to an image display time cathode voltage Vss.

Abstract: A switching transistor is controlled to turn on or off depending on a turn-on voltage or a turn-off voltage applied to a gate signal line. A driver transistor is supplied with an image signal applied to a source signal line through a switching transistor. A voltage based on the supplied image signal is retained by a capacitor. The driver transistor supplies a light-emitting current to an EL element based on the voltage retained in the capacitor. A capacitor is formed between one terminal of the capacitor (that is, a gate terminal of the driver transistor) and a gate signal line. The capacitor causes the gate terminal voltage of the driver transistor to be varied depending on variation of the potential on the gate signal line.

Abstract: Common signals VCOM during a black voltage writing period are set to be larger than common signals VCOM during a video writing period. The common voltage signals VCOM is VmH or VmL during the black voltage writing periods. The common voltage signals VCOM is VcH or VcL during video writing periods and video holding periods. The polarity of the common voltage signals VCOM is inverted alternately from frame to frame. A backlight is extinguished in the black voltage writing period.

Abstract: A driving method of an electroluminescent (EL) display device for driving the EL display device having EL elements placed in a matrix state thereon, has when a pixel line selected to write a video signal matches with a pixel line selected to supply a current to the EL elements, deselecting at least one of the pixel line selected to write the video signal and the pixel line selected to supply a current to the EL elements.

Abstract: The EL display apparatus according to this invention is provided with an EL light emitting element, a current driving device for driving the EL light emitting element by a current responsive to a source signal represented by a current, and a signal current source (634) for outputting the source signal in response to image signal to the current driving device via a source signal line, the EL display apparatus being further provided with a precharge voltage source (631) for outputting a predetermined voltage and a switching and connecting unit (636, 637) capable of selectively connecting either the signal current source or the precharge voltage source to the source signal line (638).

Abstract: An EL display apparatus in which pixels having EL elements are formed in a matrix, has a constant current circuit which generates a predetermined constant current; and a gradation voltage circuit which generates a gradation voltage; wherein the constant current generated by the constant current circuit is supplied to the pixels via a source signal line; and the gradation voltage generated by the gradation voltage circuit is supplied to the pixels via the source signal line.

Abstract: It is difficult to obtain a good image display by using an organic EL display panel. An EL display apparatus includes EL elements 15 and driving transistors 11a placed like a matrix, a voltage gradation circuit 1271 for generating a program voltage signal, a current gradation circuit 164 for generating a program current signal, and a drive circuit means of applying a signal to the driving transistors 11a, having switches 151a and 151b for switching between the program voltage signal and the program current signal.

Abstract: A precharge voltage Vp is applied in period A. The precharge voltage Vp is generated by applying a constant current Iw to a pixel driving transistor of a display panel and using gate terminal voltage of the driving transistor which passes the constant current Iw. The gate terminal potential is held in memory. When displaying images on a display panel, the gate terminal potential is read out of memory, and used as the precharge voltage Vp after arithmetic processing. By the application of the precharge voltage Vp, a source signal line is charged and discharged quickly so that an almost target tone current will flow through the driving transistor. Furthermore, a more accurate program current is written into the pixel during period B.

Abstract: The invention provides a plane display device having a display area divided into a plurality of processing blocks, the processing blocks each having a plurality of photosensor pixels 27, and the plane display device includes a precharge signal supply unit for supplying precharge signals to the respective photosensor pixels 27, a reading unit for acquiring reading signals outputted from the respective photosensor pixels 27 according to intensities of light beams irradiated on the respective photosensor pixels 27 in a state in which the precharge signals are supplied to the respective photosensor pixels 27, and a storage unit for storing data relating to the precharge signals for the plurality of photosensor pixels 27 in the corresponding processing blocks, and the precharge signal supply unit supplies the precharge signals to the respective photosensor pixels 27 on the basis of the data.