Abstract: A liquid crystal display apparatus which has a display section in which a group of scan electrodes and a group of signal electrodes are arranged in a matrix shape and a ferroelectric liquid crystal having a bistability in the direction of an electric field is filled between both of said electrode groups and displays an image or information, comprising: a circuit for sequentially writing gradation information from a pixel having a high threshold value on a scan line by a pulse to completely reset all of pixels on a selected scan electrode into a first stable state and one or a plurality of pulses subsequent to said reset pulse.

Abstract: In a ferroelectric liquid crystal element, which is constituted by holding a chiral smectic liquid crystal exhibiting ferroelectricity between electrode substrates, and in which the liquid crystal presents a plurality of surface stabilization states according to an electric field applied through the electrode substrates, and an alternating electric field having a strength equal to or higher than a constant value is applied during a period for inhibiting transition of the surface stabilization state, and to a corresponding liquid crystal portion, within a range causing no transition, the strength of the alternating electric field to be applied during the period for inhibiting transition of the surface stabilization state, and to the corresponding liquid crystal portion is set to be equal to or lower than a predetermined value which does not cause the liquid crystal to flow.

Abstract: A ferro-electric liquid crystal display is multiplex addressed by blanking and strobe waveforms applied in sequence to each electrode in one set of electrodes coincidentally with data waveforms applied to a second set of electrodes. Liquid crystal material in the display is switched by a d.c. pulse of appropriate polarity, amplitude and time. The strobe waveforms have a pulse pair comprising two pulses of different amplitude and the same or different sign. Data waveforms are rectangular waveforms of opposite sign. The amplitude and ratio of leading pulses to trailing pulses in each strobe pulse pair are adjusted to obtain the desired switching and contrast. Compensation for temperature changes is arranged by measuring the temperature of the liquid crystal material and using the value obtained to adjust the amplitude value of the leading pulse in each strobe pulse pair.

Abstract: A ferroelectric liquid crystal display system suited for use in a matrix liquid crystal display device includes scanning electrodes Lp (p=1, 2, . . . m, wherein m is a positive integer) and signal electrodes arranged so as to intersect with the scanning electrodes in the form of a matrix of columns and rows. Further, a picture element is disposed at each point of intersection between the scanning and signal electrodes. The ferroelectric liquid crystal display system is characterized in the provision of a device for indicating which one of bright and dark displays each picture element on the selected scanning electrode has previously effected.

Abstract: Driving apparatus including scanning electrodes and data electrodes, a liquid crystal assuming first and second optical states according to the polarity of a writing voltage applied thereto and disposed between the scanning and data electrodes, scanning-side and drive-side drivers, and a controller for controlling these drivers. The scanning-side drive supplies first and second scanning selections signals having mutually different voltage wave forms to the scanning electrodes so that the first and second scanning selection signals are applied alternately in respective vertical scanning periods. The data-side driver supplies data pulses to the data electrodes in synchronism with the first and second scanning selection signals so as to form one picture in at least four vertical scanning periods. The controller controls the scanning-side and data-side drivers so as to scroll each picture in at least four vertical scanning periods.

Abstract: In order to realize real-time operativity as the man-machine interface for the display on a liquid crystal display unit, there is provided a display control device for receiving image information having a plurality of graphic events, storing the received image information in an image information storing memory, and partially rewriting the display contents on the display unit by transferring the image information in a varied range by a graphic event to the display unit.

Abstract: A method for driving a ferroelectric liquid crystal panel in which a ferroelectric liquid crystal is disposed between a plurality of scanning and signal electrodes, and a select or a non-select voltage is applied to the scanning electrode whereas a rewriting or a holding voltage is applied to the signal electrode to change the display of each pixel, the method including: dividing all the scanning electrodes into a plurality of groups composed of a plurality of scanning electrodes; selecting a group whose display is to be changed; applying the select voltage to the scanning electrodes of the selected group at once; applying the rewriting voltage to the signal electrodes corresponding to the pixels whose displays are to be changed; applying the select voltage to each scanning electrode of the selected group successively; and applying the rewriting voltage to the signal electrodes corresponding to the pixels whose liquid crystal is to be placed in a second stable state.

Abstract: A liquid crystal device of the type including pixels, comprises a liquid crystal having a first and a second stable state, and which is stably driven for gradation display regardless of a change in threshold characteristic due to a temperature change, etc. The driving method includes the steps of: providing a pixel showing a transmittance (Ts) smaller than a prescribed transmittance (Tm), resetting the pixel to the first stable state and then applying at least two signals of alternating polarities to the pixel to obtain the transmittance (Ts); and providing a pixel showing a transmittance (T1) larger than the prescribed transmittance (Tm), resetting the pixel to the second stable state and then applying at least two signals of alternating polarities to the pixel to obtain the transmittance (T1).

Abstract: A liquid crystal display includes a liquid crystal cell including a pair of substrates opposite to each other, each substrate having an electrode film and an orientation control layer thereon, and a ferroelectric liquid crystal filled between the substrates; and a pair of polarizing plates which are provided opposite to each other in the state of "cross nicol" on both sides of the liquid crystal cell; the ferroelectric liquid crystal being bistable in the liquid crystal cell, the polarizing plates being oriented in such a manner that one of their polarizing directions conforms to one of extinction positions of the ferroelectric liquid crystal under no electric field, the liquid crystal cell being applied with an alternating voltage for changing which has a positive portion which gives an apparent tilt angle from one stable state, and a negative portion which gives an apparent tilt angle relative to the other stable state, resulting in display with gray scale.

Abstract: A driving method for an optical modulation device is applicable to driving of an optical modulation device, e.g. a liquid crystal device having a matrix electrode arrangement comprising a group of scanning electrodes, a group of signal electrodes oppositely spaced from the group of scanning electrodes, and an optical modulation material (e.g. a liquid crystal) showing bistability with respect to an electric filed applied thereto disposed between the groups of scanning electrodes and signal electrodes.

Abstract: An optical modulation device includes scanning electrodes and signal electrodes disposed opposite to and intersecting with the signal electrodes, and an optical modulation material disposed between the electrodes, a pixel being formed at each intersection of the electrodes and showing a contrast depending on the polarity of a voltage applied thereto. The device is driven by a method including in a writing period for writing in all or prescribed pixels among the pixels on a selected scanning electrode, a first phase for applying a voltage of one polarity having an amplitude exceeding a first threshold voltage of the optical modulation material to the all or prescribed pixels, and a second phase for applying a voltage of the other polarity having an amplitude exceeding a second threshold voltage of the optical modulation material to a selected pixel and applying a voltage not exceeding the threshold voltages of the optical modulation material to the other pixels, respectively among the all or prescribed pixels.

Abstract: A method for driving an optical modulation device of a group of scanning electrodes and a group of signal electrodes arranged so that picture elements are defined at the intersections therebetween and a bistable optical modulation material assuming one of two stable states between the groups of electrodes, by in a first phase orienting the bistable material at the picture elements on an N-th scanning electrode to one stable state, and applying a writing signal to the signal electrodes in synchronism with a scanning signal to the N-th scanning electrode and while orienting the bistable material at the picture elements on an N+1-th scanning electrode to the one stable state.

Abstract: A method for driving a spatial light modulator is disclosed. The spatial light modulator includes a ferroelectric liquid crystal layer, a pair of conductive alignment films sandwiching the ferroelectric liquid crystal layer, a pair of electrodes for applying a voltage to the ferroelectric liquid crystal layer for changing the state of the ferroelectric liquid crystal layer, a photoconductive layer disposed between one of the pair of electrodes and one of the pair of conductive alignment films.

Abstract: A technique for driving a liquid crystal apparatus having an effective display area and a non-display unit area is provided. When a bistable liquid crystal element is used, a voltage must be continuously applied to the non-display unit area to maintain a uniform white or black display state. Durability of the non-display unit is particularly desired. In this invention, the non-display unit includes first and second stripe electrodes disposed perpendicular to each other. First and second drive bipolar pulses are respectively applied to the first and second stripe electrodes with a phase difference between these bipolar pulses.

Abstract: A driving method for an optical modulation device is applicable to driving of an optical modulation device, e.g., a liquid crystal device having a matrix electrode arrangement comprising a group of scanning electrodes, a group of signal electrodes oppositely paced from the group of scanning electrodes, and an optical modulation materials showing bistability with respect to an electric field applied thereto disposed between the groups of scanning electrodes and signal electrodes.

Abstract: An electro-optical modulating system comprised of a liquid crystal device with a plurality of pixels each comprising a pair of opposite electrodes, and an optical modulating substance assuming a first molecular orientation state and a second molecular orientation state between the electrodes. The system further comprises voltage application circuit for applying to a pixel among said plurality of pixels a first voltage for resetting the pixel to be occupied with the first molecular orientation state, a second voltage for resetting the pixel into a mixture state, including a minor proportion of the first molecular orientation state and a major proportion of the second molecular orientation state, and then a third voltage for causing a prescribed ratio of the first to second molecular orientation state at the pixel not smaller than the ratio in the mixture state.

Abstract: In an active back-plane co-ordinate addressed liquid crystal cell exhibiting an analogue optical response to the application of an analogue electric potential, refreshing is carried out in two sequential stages in order to avoid cumulative charge imbalance effects. In one stage the pixels are set to their required optical states using the appropriate applied potential differences, and in the other stage the pixels are set with the same potential differences, but applied the other way round.

Abstract: A ferroelectric liquid crystal display for improving switching time and contrast comprising a ferroelectric liquid crystal having a C2U orientation, a negative dielectric anisotropy and driven by a rewriting voltage for turning a pixel on and off which is smaller than the non-rewriting voltage.

Abstract: A display control device for a dot-matrix type liquid-crystal display device with a plurality of common electrodes and data electrodes including a common electrode driver for successively applying a scan pulse to the common electrodes, and a data electrode driver for applying data signals each having black level or white level to the data electrodes. The data electrode drive is adapted to set each of the data signals to one of the black level and white level during a predetermined period of time immediately before the leading and trailing edges of the scan pulse and to the other of the black level and white level during a predetermined period of time immediately after the leading and trailing edges of the scan pulse.

Abstract: An active matrix driving method for driving a display apparatus including a plurality of pixels for receiving image data, a ferroelectric member for controlling the plurality of the pixels, and a plurality of scanning signal lines and a plurality of data signal lines for driving the plurality of the pixels utilizing a memory function caused by spontaneous polarization of the ferroelectric member.

Abstract: Disclosed is a liquid crystal apparatus including a liquid crystal panel having a pair of electrodes and a liquid crystal exhibiting spontaneous polarization and arranged between the pair of electrodes, first means for applying a gradation voltage signal corresponding to gradation information to the pair of electrodes, and second means for applying, a DC component serving as a reverse bias of an internal electric field generated upon application of the gradation voltage signal, to the liquid crystal during one vertical scanning period.

Abstract: A liquid crystal device is driven by employing a two step writing scheme. In the first step, a pixel is cleared to a second orientation state by a clearing pulse and then a voltage for writing the pixel is applied thereto. In the second step, an additional voltage for writing the pixel is applied thereto. By employing a two step writing scheme, it is possible to compensate for the difference in threshold voltage necessary to write, to a first orientation state, a pixel previously in the first orientation state and a pixel previously in the second orientation state without increasing the time between application of a clearing pulse and a writing signal.

Abstract: A display control apparatus of a display device which uses a ferroelectric liquid crystal as an operational medium to display or update image data comprises a data storage unit to store data which is displayed on a display device, a supplying unit to supply data to the data storage unit, a detector to detect a difference between the data supplied to the supplying unit and the data displayed at present on the display device, a memory to store data indicative of the result of the detection by the detector, a controller to supply the data stored in the data storage unit to the display device on the basis of the result of the detection stored in the memory, and a counter to count the number of different bits of the line detected by the detector. The detector detects such a difference for every line of the display device. The controller preferentially supplies the data to the display device in descending order of the number of bits counted for each line.

Abstract: A display control apparatus includes a frame memory for storing first frame video data on CRT image signals at least for one frame portion, a storage device for comparing the first frame video data with displaying pixel data at the same image position in video data for a subsequent frame to identify changes in the display contents on a per pixel basis and for storing address information of the changed pixels on a per pixel or per scanning line basis. Also included is a transfer device for reading displaying pixel data from the frame memory on a per pixel or per scanning line basis, based on the address information, and for transferring the data to a display driving unit of the liquid crystal display device. With this display control apparatus, a highly precise flickerless image display is implemented without any dispersion.

Abstract: A method for driving an antiferroelectric liquid crystal cell suitable for a simple-matrix display, "utilizing" third state .fwdarw.uniform state and "uniform state.fwdarw.third state" switchings, in which the uniform state to third state switching is done within a memory time of uniform to third state switching. The uniform states are employed as the light and dark states.

Abstract: A liquid crystal element includes a plurality of scanning electrodes, a plurality of signal electrodes, and a liquid crystal cell. The scanning and signal electrodes are formed in a matrix configuration. The liquid crystal cell has a pair of substrates provided with a switching device. The switching device has a gate-electrode and a source electrode at a crossing point of the above scanning electrodes and signal electrodes. A ferroelectric liquid crystal fills the liquid crystal cell. Furthermore, the scanning electrode is connected with the gate-electrode of the switching device, and the signal electrode is connected with the source-electrode of the switching device. The scanning electrode transmits a signal to turn on the switching device, and, simultaneously, the signal electrode transmits a multiple-value signal to drive the liquid crystal cell.

Abstract: A method of driving a ferroelectric liquid crystal element which enlarges the effective cone angle. A ferroelectric liquid crystal is held between two substrates such that the helix is suppressed and a chevron layer structure is present. The ferroelectric material has a positive dielectric anisotropy. A first pulse is applied which causes switching from one state to the other, and a subsequent smaller AC pulse is applied which does not cause switching. The second pulse voltage control the effective cone angle, enabling grey scale.

Abstract: A display system includes a display panel provided with matrix electrodes composed of scanning lines and information lines, a first unit for transferring scanning line address information and image information corresponding to the writing into pixels of a scanning line, a second unit for delaying the transfer of the received image information and then latching the image information of a scanning line, and a third unit for designating a scanning line based on the received scanning line address information and storing the designation information of the designated scanning line.

Abstract: In a ferroelectric liquid crystal panel, the switching current of spontaneous polarization is detected from the difference between the current supplied to a selected pixel and the constant multiplication of the current supplied to a non-selected reference pixel, and when the amount of switched spontaneous polarization reaches a desired gray scale level, the applied voltage is changed so that even if any nonuniformity is involved within the panel, a uniform analog gray scale display can be realized.

Abstract: A ferroelectric liquid crystal display device comprising a substrate of a plurality of scanning electrodes and a plurality of signal electrodes in the form of a matrix, a switching device formed at each intersecting point of the electrodes, a liquid crystal cell injected with a ferroelectric liquid crystal and a drive controlling means which can apply a signal having a polarity opposite to that of the signal corresponding to a required display from the signal electrode in synchronization with that the signal is applied from the scanning electrode to turn the switching device ON; apply a signal corresponding to the required display from the signal electrode in synchronization with that the signal is applied again from the scanning electrode after a predetermined period of time to turn the switching device ON; and apply a signal from the signal electrode so that the voltage applied to the liquid crystal may be zero in synchronization with that the signal is applied again from the scanning electrode after a pred

Abstract: A display apparatus includes a matrix of electrodes formed of scanning electrodes and information electrodes. A scanning device uses a plurality of scanning methods for selecting scanning electrodes and performs the scanning methods according to respective priorities, and a driving device changes driving conditions according to the scanning methods or the priorities thereof.

Abstract: A ferroelectric liquid crystal display device is disclosed, which takes a specified period to rewrite the picture elements in one horizontal scanning period, and includes M scanning lines divided into a plurality of groups each containing K scanning lines (K>1, M>1, K, M: positive integers) and elements for supplying scanning signals to the M scanning lines to rewrite an image. The scanning signal-supplying elements output scanning signals to the first scanning line of each group in the first frame, to the second scanning line of each group in the second frame, and to the Kth scanning line of each group in the Kth frame so that the M scanning lines are rewritten by K times of scanning.

Abstract: An interlaced scanning, in which every adjoining plural scanning electrodes are rewritten at the rate of one scanning electrode and all of the picture elements are rewritten in plural fields, is conducted at a constant period. Furthermore, during the transcribing operation of the picture elements, a partial rewriting operation is performed wherein a selective voltage is applied to the scanning electrode where data to be displayed on the picture elements of liquid crystal display device has changed, and a signal voltage is applied to the signal electrode responsive to, whether the picture elements on the selected scanning electrode should be changed from a bright display state to a dark display state, or from the dark display state to the bright display state, or the bright and dark display states are not changed.

Abstract: A method and an apparatus of driving a ferroelectric liquid crystal display device are provided having N scanning electrodes, and M data electrodes arranged in the form of an N.times.M matrix, N and M being positive integers, and a pixel being formed at each intersection of the scanning electrodes and the data electrodes of the matrix. The method comprises the step of applying a selected scanning signal to a Kth selected scanning electrode in a time period, wherein K is a positive integer and K.ltoreq.N. A selected data signal is applied to a data electrode in the time period to form a synthetic voltage at a selected pixel, and an auxiliary signal voltage is applied to a (K-A) scanning electrode in the time period, wherein A is a positive integer and 1<A<N.

Abstract: In a method of driving a matrix of ferroelectric liquid crystal devices in a TDM mode, each strobing signal comprises first and second pulses (20,21) of opposite polarities and of different amplitudes, together with a dc voltage (26) which is applied from the end of the second pulse to the beginning of the first pulse of the next strobing signal on the same strobe line to cancel the dc level which would be caused by the unequal pulses. Data ON signals applied selectively to data lines of the matrix comprise two consecutive pulses (22,23) of opposite polarities. Data OFF signals (24,25) may be the inverse of the data ON signals or may comprise a constant dc level. The combination of the two pulses with a dc level to form each strobing signal means that only two strobe pulse time slots per frame are required for addressing each strobe line, as compared with the conventional systems in which four time slots per frame are required.

Abstract: A liquid crystal apparatus includes: a ferroelectric liquid crystal device comprising an electrode matrix including a plurality of scanning lines and a plurality of data lines intersecting with the scanning lines, and a ferroelectric liquid crystal disposed between the scanning lines and data lines, and a driver for sequentially applying a scanning signal to the scanning lines for selecting a particular scanning line, and for applying data signals for the pixels on the selected scanning line to the data lines. Each of the data signals has a plurality of pulses including a pulse in a controlled phase and a pulse in an auxiliary phase, and the scanning signal for the selected scanning line has a compensation pulse for compensating the pulse in the auxiliary phase of a data signal for a pixel on the selected scanning line.

Abstract: In a method of driving a ferroelectric liquid crystal display, a blanking pulse of width 2t.sub.s followed, after a delay of n.multidot.t.sub.s (where n is an integer), by a writing pulse of width t.sub.s and of opposite polarity to the blanking pulse are applied to successive row address lines at intervals of 2t.sub.s. Pairs of bipolar data pulses of width t.sub.s are applied to column address lines so that the data pulses coincide with the blanking pulse applied to the ith row and the writing pulse applied to row i-(n+1)/2 for odd values of n and to row 1-(n+2)/2 for even values of n. The data pulse amplitude may be varied in order to obtain variable grey levels in the display.

Abstract: An optical modulation device includes scanning electrodes and signal electrodes disposed opposite to and intersecting with the signal electrodes, and an optical modulation material disposed between the electrodes, a pixel being formed at each intersection of the electrodes and showing a contrast depending on the polarity of a voltage applied thereto.