2932 results about "Electroluminescent display" patented technology

A photosensor is disposed in each pixel, and the brightness is adjusted for each pixel depending on the light quantity of an organic EL element. The adjustment of brightness is realized by making the current amount of a pixel with a high brightness small in accordance with a pixel with a small light emission amount. Thus, low power consumption can be achieved, and the unevenness of brightness can be corrected. By disposing the photosensor to configure a photoreceptor circuit in each pixel, the unevenness of brightness is corrected. Further, it becomes possible to correct brightness in a brightness half-life. Hence, a longer lifetime can be achieved.

Novel materials for electron injection/transportation and emitting layers can greatly improve the stability of an organic electroluminescent display. Electroluminescent displays incorporating these materials produce blue light at low voltage levels. These novel organic materials include compounds in which 1 to 2 imidazole functional groups are introduced in the 2 or 2,6-site of 9,10 substituted anthracene. An organic electroluminescent display with an organic compound layer of these materials has high efficiency, thermal stability, operationally stability and maintains driving voltage before and after operation.

An active matrix electroluminescent display device has a current sampling resistor within each pixel in series with the display element. A feedback signal represents the voltage drop across the current sampling resistor and the pixel drive signals are modified in dependence on the feedback signal to control the current driven through the display element. In this way, threshold compensation is provided, whilst enabling a single voltage-driven drive transistor to be employed.

In an active-type electroluminescent (EL) display, a conductor interconnecting a cathode (55) of an EL panel (30, 40) and a connection terminal of a signal input substrate (35) has a multilayer structure formed of a cathode material and a conductive material used in a thin-film transistor forming step. The conductor may be formed of a conductive material used in a thin film transistor forming step. A metal material for a gate electrode or drain electrode is preferably used as the conductive material. The connection conductor structure can reduce the electrical resistance of the connection conductor, thus preventing a decrease in display intensity of an EL display.

The invention provides an organic EL display device fabrication system comprising a loading side normal-pressure delivery chamber 11 including a first substrate delivery means 61 for delivering a substrate with no film formed thereon, and a loading chamber 21 connected thereto for introducing the substrate from loading side normal-pressure delivery chamber 11 at normal pressure into a vacuum delivery chamber 31 at a vacuum. The vacuum delivery chamber 31 is connected to loading chamber 21 and includes a second substrate delivery means 62 for delivering the substrate in a vacuum, and has one or two or more film formation chambers 32 to 35 connected thereto. The system further comprises an unloading chamber 41 connected thereto for delivering the substrate out of vacuum delivery chamber 31 at a vacuum into an unloading side normal-pressure delivery chamber 51 at normal pressure. The unloading side normal-pressure delivery chamber 51 is connected to unloading chamber 41 and includes a third substrate delivery means 63 for delivering a substrate with films formed thereon. An inert gas atmosphere having a moisture content of up to 100 ppm is maintained in both unloading chamber 41 and unloading side normal-pressure delivery chamber 51 at normal pressure. The invention also provides an organic EL display device fabrication process using this fabrication system.

An electroluminescent device including a transparent substrate, a securing layer, a light scattering layer, an electroluminescent unit including a transparent electrode layer, a light emitting element including at least one light emitting layer, and a reflecting electrode layer in that order, wherein the light scattering layer includes one monolayer of inorganic particles having an index of refraction larger than that of the light emitting layer and wherein the securing layer holds the inorganic particles in the light scattering layer.

Disclosed is a transparent carbon nanotube (CNT) electrode using a conductive dispersant. The transparent CNT electrode comprises a transparent substrate and a CNT thin film formed on a surface the transparent substrate wherein the CNT thin film is formed of a CNT composition comprising CNTs and a doped dispersant. Further disclosed is a method for producing the transparent CNT electrode.

The transparent CNT electrode exhibits excellent conductive properties, can be produced in an economical and simple manner by a room temperature wet process, and can be applied to flexible displays. The transparent CNT electrode can be used to fabricate a variety of devices, including image sensors, solar cells, liquid crystal displays, organic electroluminescence (EL) displays and touch screen panels, that are required to have both light transmission properties and conductive properties.

A controller for use with a multi-segment electroluminescent display 1. Control signals C1–CN control a plurality of half H-bridges H and Hc, the terminals of the half H-bridges being connected respectively to ground and to a high voltage DC supply 9. One of said half H-bridges provides a common output Vcommon and the remaining H-bridges provide drive voltages V1–VN for the segments of the display. The H bridges are driven by an oscillator 14 so that an AC voltage is selectively applied to the segments of the display. A power supply 24 provides a predetermined amount of power per unit area of the display. This is controlled by an area summation engine 22 having a segment data input, a segment counter and a memory containing area data corresponding to the segment(s) of the display. Based on the input from the segment data input, the area(s) of the segment(s) that are to be lit are obtained from the memory and summed to provide the total area to be lit. This is fed to the power supply 24, which then feeds the correct amount of power to display 1 via the half H-bridges.

Subpixels on an electroluminescent (EL) display panel, such as an organic light-emitting diode (OLED) panel, are compensated for initial nonuniformity (“mura”) and for aging effects such as threshold voltage V_th shift, EL voltage V_oled shift, and OLED efficiency loss. The drive current of each subpixel is measured at one or more measurement reference gate voltages to form status signals representing the characteristics of the drive transistor and EL emitter of those subpixels. Current measurements are taken in the linear region of drive transistor operation to improve signal-to-noise ratio in systems such as modern LTPS PMOS OLED displays, which have relatively small V_oled shift over their lifetimes and thus relatively small current change due to channel-length modulation. Various sources of noise are also suppressed to further increase signal-to-noise ratio.

An organic electroluminescent display device including first to fourth pixel regions each including red, green and blue sub-pixel regions, each of the first to fourth pixel regions being divided into first and second column, and the first column being divided into first and second rows, wherein a red sub-pixel region and a green sub-pixel region are respectively arranged in the first and second rows, and a blue sub-pixel region is arranged in the second column; a red emitting layer formed in the red sub-pixel region; a green emitting layer formed in the green sub-pixel region; and a blue emitting layer formed in the blue sub-pixel region.

The invention discloses pixel driving circuit and method of an active organic electroluminescent display. The pixel driving circuit comprises a driving transistor, four switch transistors, a coupling capacitor, a storage capacitor and a light-emitting diode, wherein a drain electrode of the first transistor is connected with a data wire, a grid electrode of the first transistor is connected with a first scanning control wire, and a source electrode of the first transistor is connected with the C end of the coupling capacitor; a drain electrode of the second transistor is connected with source electrodes of the third transistor and the fourth transistor, a grid electrode of the second transistor is connected with the A ends of the coupling capacitor and the storage capacitor and a drain electrode of the third transistor, and a source electrode of the second transistor is connected with a drain electrode of the fifth transistor and the B end of the storage capacitor and is grounded through the organic light-emitting diode; a grid electrode of the third transistor is connected with a second scanning control wire; a drain electrode of the fourth transistor is connected with a power wire, and a grid electrode of the fourth transistor is connected with a light-emitting control wire; and a grid electrode of the fifth transistor is connected with the first scanning control wire, and a source electrode is grounded. The invention can effectively compensate the unevenness of threshold voltages of the transistors and the degradation of a start voltage of the OLED (Organic Light Emitting Diode), ensures that the brightness of an image displayed by the OLED is even and realizes high contrast.

A method for increasing ambient light contrast ratio within an electroluminescent device, including: a reflective electrode and a transparent electrode having an EL unit formed there-between. The EL unit includes a light-emitting layer containing quantum dots. Additionally, the method includes locating a contrast enhancement element on a side of the transparent electrode opposite the EL unit. The contrast enhancement element includes a patterned reflective layer and a patterned light-absorbing layer whose patterns define one or more transparent openings, so that light emitted by the light-emitting layer passes through the one or more transparent openings. The patterned reflective layer is located between the patterned light absorbing layer and the transparent electrode.

An electroluminescent device comprising a first electrode and a second electrode having an EL unit formed there-between, wherein the EL unit comprises a light-emitting layer containing quantum dots, and the first and second electrodes define one or more light-emitting areas; wherein at least a portion of the second electrode is transparent and light emitted by the EL unit is viewed from a first side of the electroluminescent device that is nearer the second electrode; and one or more reflective elements that are electrically-conductive and are formed as part of the second electrode or in electrical communication with the second electrode; and wherein the reflective elements are located at least partially within the light emitting areas.

To reduce the influence of generation of heat at scan driver ICs during the application of a scan signal with reduced time of charge and discharge and to eliminate the problem of a rush current, in an EL display where scan driver Ics sequentially apply a scan signal to a plurality of scan electrodes and data driver IC applies a data signal to data electrodes to selectively cause EL elements to emit light responsive to the scan signal and data signal, constant current control circuits are provided to control charge and discharge currents at constant currents during the application of the scan signal to the scan electrodes by the scan driver ICs.

An organic electroluminescent display device includes a driving TFT and pixels which are formed by organic electroluminescent elements and provided in a pattern on a substrate of the TFT. The driving TFT includes at least a substrate, a gate electrode, a gate insulating film, an active layer, a source electrode, and a drain electrode; the driving TFT further includes a resistive layer between the active layer and at least one of the source electrode and the drain electrode; and the pixels are formed in a pattern by a laser transfer method. A patterning method by a laser transfer method for producing the fine pixels is also provided.