Abstract: A method of driving a gray scale and a drive circuit therefor are provided in which the simplification and reduction of the operating speed of a circuit for generating display voltages in a matrix display device are promoted, and low cost and multi-color display of high minuteness are simultaneously realized. The display circuit for generating the display voltages is composed of an image signal processing circuit for dividing an input digital image signal into plural bit groups, a first display voltage generating circuit for generating the display voltages corresponding to the first bit group obtained by the division, a second display voltage generating circuit for generating the display voltages corresponding to the second bit group obtained by the division, and a line-at-a-time timing circuit. The first and second display voltage generating circuits are operated in parallel to combine the outputs thereof with one another, thereby to generate a gray scale displaying voltage.

Abstract: A liquid crystal display includes a liquid crystal matrix panel for displaying information having a plurality of liquid crystal pixels which are arranged in a matrix and to which driving voltages are applied from X electrodes and Y electrodes, a driving circuit for supplying the driving voltages to the Y electrodes, and a circuit for superimposing a compensating voltage for masking waveform distortion of a liquid crystal driving voltage by constantly changing the waveform thereof on at least one of the X electrode driving circuit and the Y electrode driving circuit.

Abstract: A gray scale display, which is provided with a liquid crystal panel consisting of switching elements and a liquid crystal layer superposed thereon; a digital-time function transforming device for transforming digital signals including gray scale information into time function signals; and a time function-gray scale transforming device for sampling a brightness reference signal varying with respect to time, responding to the time function signals and generating gray scale signals corresponding to the signal voltage applied to the switching elements. The time function-gray scale transforming device, in which the brightness reference signal is inputted, samples the signal, responding to time function signals such as a pulse phase signal, a pulse width signal, etc., to obtain a signal voltage. In this way it is possible to reduce the size of a signal voltage generating circuit and to lower signal speed of the operation of the circuit.

Abstract: A high-speed scanning method uses a K(K.gtoreq.3)-number of semiconductor switch elements each having a first main electrode responsive to an input signal, a second main electrode, and a control electrode responsive to a control signal for controlling the transmissive and intransmissive states of said input signal from the first main electrode to the second main electrode; and capacitive loads connected respectively with the second main electrode of each of said K-number of semiconductor switch elements, for shifting one of the K-number of semiconductor switch elements sequentially with a predetermined period from the transmissive state to the intransmissive state or vice versa, wherein, the time, for which an arbitary L(K>L.gtoreq.

Abstract: In a matrix display device, a signal drive circuit comprises selection means for sequentially selecting at least one of display information signals corresponding to a plurality of signal electrodes when at least one of a plurality of scan electrodes is selected, hold means for holding the display information signal selected by the selection means until selection of at least corresponding scan electrode is completed, and voltage conversion means for selecting one of a plurality of voltage levels in accordance with the display information signal held by the hold means and supplying the selected voltage level to the signal electrodes. Since the display information signal is held by the hold means until the selection of at least corresponding scan electrode is completed, one of the plurality of voltage levels is always applied to the signal electrodes and the switching elements do not assume the high impedance state.

Abstract: An information holding device comprising a pair of substrates whose opposing surfaces are formed with electrodes on one side and electrodes on the other side so that they may oppose and that opposing parts between the electrodes on the one side and those on the other side may form a matrix as a whole, a dielectric which is held between said pair of substrates, means to change a capacitance of the dielectric in any desired one of the opposing parts, and detection means to simultaneously detect the capacitances of at least two of the opposing parts between the electrodes on the one side and those on the other side.

Abstract: An information input/output display device comprising a dielectric which is held in a portion between one electrode and the other electrode opposite to each other and which has at least a first state and a second state of unequal capacitances, means to change the capacitance of the dielectric, capacitance holding means to hold at least temporarily a value of the capacitance of the dielectric in the first state, and means to compare the value of the capacitance of the dielectric with the value of the capacitance held by the capacitance holding means, whereby information can be read out without being affected by fluctuations in a distance d between the electrodes or/and in an ambient temperature T.

Abstract: A color liquid crystal display device wherein a nematic liquid crystal to which a dichroic dye and an optically active substance have been added is used as the liquid crystal layer and the amount of said optically active substance added is so selected as to fall in a range making steep the threshold voltage characteristics of the liquid crystal.

Abstract: An apparatus and a method for driving a guest-host type phase transition liquid crystal in matrix is disclosed in which X and Y electrodes in matrix comprising a guest-host liquid crystal made by adding a pleochroic dye to the cholesteric-nematic phase transition liquid crystal or chiralnematic phase transition liquid crystal are impressed with an X electrode selecting voltage, an X electrode non-selecting voltage, a Y electrode selecting voltage and a Y electrode non-selecting voltage selectively thereby to apply a holding voltage for holding the display condition of the liquid crystal cells of the liquid crystal display elements and a write-in voltage for new write-in. The region where the display condition is to be erased is designated in the liquid crystal display panel.

Abstract: A driving device for a matrix-type display panel using a guest-host type liquid crystal made by adding a pleochroic dye to a nematic-cholesteric phase transition liquid crystal or a chiralnematic phase transition liquid crystal is disclosed in which the display plane of a display panel is divided into a plurality of blocks in such a manner that each block includes a plurality of scanning lines, that is, a plurality of regions are formed, only one of the regions is selected to be used a scanning region, the one-line-at-a-time scanning operation is repeated many times in the scanning region in order to write and display information to perfection, and the regions are selected successively and cyclically to be used as the scanning region.