Unlock instant, AI-driven research and patent intelligence for your innovation.

Active matrix drive type display device

A display device and active matrix technology, applied in the direction of lighting devices, light sources, electric light sources, etc., can solve the problems of not being proportional to the size of the data voltage, increasing power consumption, and deteriorating image quality, so as to prevent uneven display and save energy. Effects of power consumption and suppression of ineffective power

Inactive Publication Date: 2004-08-04
SANYO ELECTRIC CO LTD
View PDF1 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, even after the Figure 52 In the organic EL display device composed of pixels 51 as shown, it is unavoidable that dispersion deviation occurs in the characteristics of the plurality of transistors constituting the comparator 9. As a result, the time when the comparator 9 becomes a low value, that is, the organic EL element The time for the current to flow within 50 cannot be correctly proportional to the magnitude of the data voltage, and there are problems of uneven display and image quality degradation
Furthermore, in the display device disclosed in Patent Document 2 or Patent Document 4, the current flowing through the comparator is of a non-negligible magnitude compared with the current flowing through the organic EL element, and there is a problem of increased power consumption.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Active matrix drive type display device
  • Active matrix drive type display device
  • Active matrix drive type display device

Examples

Experimental program
Comparison scheme
Effect test

no. 1 Embodiment

[0088] The display panel 5 is configured by arranging pixels 51 of the circuit configuration shown in FIG. 2 in a matrix. Each pixel 51 includes: an organic EL element 50; a driving transistor TR2 for turning on / off the energization to the organic EL element 50 according to an on / off control signal input to the gate; The writing transistor TR1 turned on by scanning the scanning voltage of the driver; the capacitive element C1 to which the data voltage from the data driver is applied when the writing transistor TR1 is turned on; The supplied ramp voltage RAMP is used by the pulse width modulation control circuit 90 for performing pulse width modulation on the output voltage of the capacitive element C1. Both ends of the capacitive element C1 are connected to the drain of the writing transistor TR1 and the ramp voltage supply line, respectively. The pulse width modulation control circuit 90 is provided with the on-control transistor TR3 for on-drive transistor TR2, and the off-...

no. 2 Embodiment

[0099] Such as Figure 4 As shown, in the circuit configuration of each pixel 51, the pulse width modulation control circuit 90 includes an on-control transistor TR3 for on-driving transistor TR2 and an off-control transistor for off-drive transistor TR2. TR4, but in addition to supplying the output voltage (data voltage) of the capacitive element C1 to the gate of the on-control transistor TR3 and supplying the ramp voltage RAMP to the gate of the off-control transistor TR4, the capacitive element is connected in parallel with the opposing transistor TR5 Except for C3, it has the same configuration as that of the first embodiment.

[0100] In an organic EL display device composed of pixels 51, such as Figure 5 As shown, during the light-emitting period, the ramp voltage RAMP rises, and with this point A voltage rises, and the low-potential power supply voltage V SS When the difference increases, and exceeds the threshold level Vth between the gate and the source of the on-...

no. 3 Embodiment

[0106] As shown in FIG. 6, the pulse width modulation control circuit 90 of each pixel 51 includes an on-control transistor TR3 for turning on the driving transistor TR2, and an off-control transistor TR4 for turning off the driving transistor TR2. In the organic EL display 2, a high-potential power supply V common to each pixel 51 is provided. DD with a low potential supply V SS , at a high potential supply V DDThe source of the driving transistor TR2 of each pixel 51 is connected to the top. The on-control transistor TR3 and the off-control transistor TR4 are connected in parallel with each other between the power supply V DD with V SS At the same time, the transistor TR5 and the capacitive element C4 are interposed in series with each other, and the connection point B between the transistor TR5 and the capacitive element C4 is connected to the gate of the driving transistor TR2.

[0107] The ramp voltage RAMP is supplied to the gate of the on-control transistor TR3, and...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention provides a display device of the active matrix drive type wherein each of pixels (51) comprises an organic EL display element (50), a drive transistor (TR2) for energizing or deenergizing the EL display element (50), a write transistor (TR1) to be brought into conduction when impressed with scanning voltage, a capacitance element (C1) to be impressed with data voltage by the conduction of the write transistor (TR1), and a pulse-width modulation control circuit (90) for on / off-controlling the drive transistor (TR2) by pulse-width-modulating the output voltage of the capacitance element (C1) with ramp voltage. The modulation control circuit (90) comprises an on-control transistor (TR3) and an off-control transistor (TR4).

Description

technical field [0001] The present invention relates to a display device, such as an organic electroluminescent display device, including a display panel configured by arranging a plurality of pixels in a matrix. Background technique [0002] In recent years, the development of organic electroluminescent displays (hereinafter referred to as organic EL displays) has been progressing, for example, the use of organic EL displays in mobile phones has been investigated. As driving methods for organic EL displays, there are known a passive matrix driving method using time-division driving of scan electrodes and data electrodes, and an active matrix driving method of maintaining light emission of each pixel within one vertical scanning period. [0003] In an active-driven organic EL display, such as Figure 51 As shown, each pixel 52 is equipped with an organic EL element 50, a drive transistor TR2 for controlling energization to the organic EL element 50, a write transistor TR1 tu...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): H01L51/50G09G3/20G09G3/30G09G3/32G09G5/00H05B33/00H05B33/14
CPCG09G2310/0251G09G3/3258G09G2300/0809G09G2300/0852G09G2320/045G09G2300/0819G09G2300/0876G09G3/2014G09G2300/0842G09G3/3233G09G2310/066G09G3/3291G09G2330/021G09G2310/0259A47J36/06Y10S220/912
Inventor 山下敦弘野口幸宏
Owner SANYO ELECTRIC CO LTD