摘要:
Disclosed is a driving method for a thin-film electroluminescent element of a three-layer construction which emits light and exhibits the hysteresis phenomenon within the light emission versus applied voltage characteristics. The light intensity is maintained and memorized at a predetermined value in the element by the application of a train of sustaining pulses of alternating voltage, the amplitude thereof being chosen at the voltage level appearing at the point in the hysteresis loop characteristics where the difference between the maximum light brightness on the voltage decreasing curve and the minimum light brightness on the voltage increasing curve is considerably large. The sustaining light brightness is controlled by varying the amplitude or the pulse width of the sustaining pulses. The information may be written, memorized and eliminated in the EL element as variations of the light brightness. To write or eliminate the information in the EL element, it is also effective to utilize external light excitation.
摘要:
The present disclosure is directed toward a drive method and circuit for a memory matrix panel which comprises a light-emitting body having hysteresis behavior responsive to application of a desired AC voltage, a plurality of horizontal electrodes disposed on a first major surface of the light-emitting body and a plurality of vertical electrodes disposed on a second major surface of the light-emitting body, each cross point of the both electrodes providing a light-emitting unit point in a matrix array. A period of the applied AC voltage includes at least three sections wherein, prior to the writing, erasing or reading of information, a horizontal maintenance pulse having an amplitude necessary to maintain light emittance is applied to the plurality of horizontal electrodes during the first section thereof and a vertical maintenance pulse having an amplitude necessary to maintain light emittance is applied to the vertical electrodes during the second section thereof. In order to perform the writing, erasing or reading of information on a selected cross point, the vertical (or horizontal) electrode associated with such point receives an enable pulse having the shape identical with that of the horizontal maintenance pulse but the phase shifted into the third section, whereas the associated horizontal (or vertical) electrode receives write, erase or read out each having a predetermined amplitude necessary to perform the write, erase or read operation, the respective amplitude being superimposed on the enable pulse.
摘要:
A coil is serially connected to a capacitive display unit, such as an EL display panel, which includes an insulating display element sandwiched between a pair of electrodes. The coil and the electrostatic capacitance of the display unit function, in combination, to form an LC resonance circuit, which limits transient current flowing through the insulating display element and enables the display unit to operate in a low power dissipation mode. An alternating driving signal to be applied to the display unit has an intermediate potential period on which a writing pulse is superimposed, thereby to minimize high voltage requirement of the writing circuit.
摘要:
Disclosed is a photo-image memory panel composed of an electroluminescent element which exhibits electrical polarization effects upon light excitation. Under the conditions when the panel is biased by DC voltage or DC offset voltage, light irradiation is applied to the panel to establish a light-activated polarized electric field of which the intensity is controllable in dependence upon a photo-image desired to be written into the panel. Then, the photo-image written into the panel is held while maintaining the polarized electric field. Thereafter, application of a predetermined voltage pulse enables the reading out of the photo-image in the form of light emission. Alternatively, in case of an electroluminescent element of which the light emission versus applied voltage characteristics involve the hysteresis phenomenon, a train of alternating current pulses are employed as reading-out pulses to maintain light emission corresponding to the read-out image.
摘要:
Disclosed is a photo-image memory panel composed of an electroluminescent element which exhibits electrical polarization effects upon light excitation. Under the conditions when the panel is biased by DC voltage or DC offset voltage, light irradiation is applied to the panel to establish a light-activated polarized electric field of which the intensity is controllable in dependence upon a photo-image desired to be written into the panel. Then, the photo-image written into the panel is held while maintaining the polarized electric field. Thereafter, application of a predetermined voltage pulse enables the reading out of the photo-image in the form of light emission. Alternatively, in case of an electroluminescent element of which the light emission versus applied voltage characteristics involve the hysteresis phenomenon, a train of alternating current pulses are employed as reading-out pulses to maintain light emission corresponding to the read-out image.
摘要:
A thin-film electroluminescent display panel is sealed by a pair of glass substrates for protecting itself from the environment. A protective liquid is introduced between a counter glass substrate and a substrate for supporting the electroluminescent display panel. The protective liquid comprises silicon oil or grease which assures the thin-film electroluminescent panel of preservation of the electroluminescent display panel. The counter glass substrate is bonded to the substrate through an adhesive of, for example, photocuring resin. A capillary tube is provided within the substrate for injecting the liquid under vacuum conditions. The counter glass substrate can be plate-shaped thereby eliminating a spacer. The liquid has the ability of spreading into pin holes generated on dielectric layers, and is resistant to high voltage, high humidity and high temperature, and is inert to layers constituting the thin-film electroluminescent display panel and has a small vapor pressure and a small coefficient of thermal expansion.
摘要:
A drive circuit for a thin-film electroluminescent (EL) matrix display panel includes an odd side N-ch high voltage MOS driver, and an odd side P-ch high voltage MOS driver connected to odd number scanning electrodes of the thin-film electroluminescent (EL) matrix display panel. Even number scanning electrodes of the thin-film electroluminescent (EL) matrix display panel are connected to an even side N-ch high voltage MOS driver and an even side P-ch high voltage MOS driver. The four MOS drivers are effectively controlled to perform an alternating current driving of the thin-film electroluminescent (EL) matrix display panel. A source level switching circuit is connected to the odd side and even side N-ch high voltage MOS drivers so as to switch the source voltage in synchronization with the field driving of the thin-film electroluminescent (EL) matrix display panel.
摘要:
A display device includes an EL panel including an array of scan electrodes, an array of data electrodes crossing the scan electrodes and a plurality of pixels each lying sandwiched between a respective one of the scan electrodes and a respective one of data electrodes, a circuit for applying sequentially a write pulse voltage V.sub.W to the scan electrodes in a line scanning fashion and a circuit for applying a refresh pulse voltage V.sub.R of a polarity opposite that of the write pulse voltage V.sub.W throughout the panel upon completion of field scanning. A circuit is further provided for applying throughout the display panel upon completion of field scanning a pulse voltage having the same polarity as that of the refresh pulse V.sub.R and an amplitude insufficient to cause electroluminescence. Alternatively, a pulse voltage having a polarity opposite that of the refresh pulse V.sub.R and an amplitude insufficient to cause electroluminescence may be applied after the application of the refresh pulse V.sub.R is completed.
摘要:
A drive device for driving a matrix-type LCD apparatus comprises a voltage signal supply means for outputting a plurality of voltage signals with different levels. The voltage signals have alternately positive and negative levels with respect to an AC reference voltage applied to a counter-electrode of the LCD apparatus. The AC reference voltage is approximately 180.degree. out-of-phase with the voltage signals. The drive device also comprises a signal electrode drive means which selects one of the voltage signals depending upon an input digital video signal, and which supplies the selected voltage signal to a signal electrode of the LCD apparatus.