Fujitsu Corporation

Yoshinori Kiyota

Toshiaki Yoshihara

Tetsuya Makino

Hironori Shiroto

Shinji Tadaki

Keiichi Betsui

Shigeo Kasahara

Akihiro Mochizuki

In a liquid crystal display device that uses a liquid crystal material having spontaneous polarization and is actively driven by a TFT, a voltage corresponding to image data is applied twice by driving the TFT of each pixel electrode on a line by line basis of a liquid crystal panel, during writing in one frame. During erasure in one frame, voltage application to liquid crystal by batch selection of all the pixel electrodes is performed three times. With this three times of voltage application, it is possible to achieve a black display state in each pixel and make the stored charge amount at the liquid crystal in each pixel substantially zero.

Driving method of liquid crystal display device and liquid crystal display device

A liquid crystal display device displays an image by stacking a plurality of liquid crystal panels, and by controlling a light transmittance with voltage application to liquid crystal of each panel, wherein during execution of voltage application to the liquid crystal of one of the panels, a voltage to the liquid crystal of the other panel serves as a non-display voltage. No image is displayed simultaneously on the two or more stacked liquid crystal panels. In the liquid crystal panel to which no voltage is applied and on which no image is displayed, the longitudinal axial direction of liquid crystal molecules coincides with the polarizing axial direction of polarizers, or is orthogonal to the polarizing axial direction; therefore, no influence is exerted on the overall double refraction, and the overall voltage-transmitted light intensity characteristic corresponds to the sum of the voltage-transmitted light intensity characteristics of the respective panels.

Liquid crystal display device and display method

A liquid crystal panel includes a glass substrate with pixel electrodes that are arranged in a matrix shape, TFTs that are connected to the pixel electrodes, and a glass substrate with an opposing electrode and color filters that are arranged in a matrix shape. A liquid crystal layer is formed in a space between the glass substrates by filling a ferroelectric liquid crystal into the space. When writing display data, and when deleting display data that has been written, a voltage, not including 0V, that becomes a voltage potential, or in other words, a voltage that is greater than a threshold voltage at which the optical characteristic of the filled ferroelectric liquid crystal changes is applied between the opposing electrode and pixel electrodes. An image is displayed over all gradation numbers, including the low-gradation side, and the display characteristic is improved.

Drive method for liquid crystal display device and liquid crystal display device

Liquid crystal display device having spontaneous polarization

A liquid crystal material is used in which the maximum angle of the optical axis change by liquid crystal molecule when a voltage of one polarity is applied is larger than 45 degrees and a condition of |2Ps&#xb7;A|&#x3e;|5(V)Clc&#xb7;A| is satisfied where Ps (nC/cm) is the magnitude of the spontaneous polarization per unit area, A (cm) is the electrode area of the pixel and Clc (nF/cm) is the liquid crystal capacity per unit area. The transmittance in the liquid crystal part is increased and excellent display can be performed without the provision of a storage capacitor. Consequently, the storage capacitor is unnecessary, so that the aperture ratio of the liquid crystal panel can be increased.

Liquid crystal display device

There is provided a liquid crystal display including a panel using a liquid crystal material having spontaneous polarization, such as ferroelectroic liquid crystal (FLC), having a faster response time suitable to display dynamic images. The FLC has the disadvantage caused by the incomplete memory effect at during driving for displaying 'black' in several frames, where the light transmittance is preferably desired zero. The panel in the display are driven signals so that the driving signals are applied across the picture element, where the signals are positively or negatively offset to reference voltage of the panel.

Display panel including liquid crystal material having spontaneous polarization

Although portions of electrodes in proximity to a driver IC are covered with an insulating film, part of the electrodes is not covered with the insulating film. Thus, this insulating film absent region functions as an external voltage supply region that receives, from the outside, application of a voltage which is different from an output voltage from a driving unit. When the alignment of the initial state is disarranged, an alignment process is performed by short-circuiting all electrodes of the driving unit and applying a voltage from the outside, through the external voltage supply region, whereby the alignment is restored to the initial state with the driving unit being mounted on a liquid crystal panel.

Liquid crystal display device and alignment process method

A liquid crystal display device comprising: a peripheral electrodethat is formed around the outside of a display regionon a liquid crystal paneland that generates an orientation state that is equivalent to that of the display region; and an inverted electrodethat is formed around the outside of the peripheral electrodeand that generates an orientation state that has polarity opposite to that of the display region; wherein the peripheral electrodeand the inverted electrodehave bipectinate construction and are arranged on both sides of a non-oriented buffer region. Orientation defects that are generated in a seal are trapped inside the buffer regiondue to the existence of the peripheral electrodeand inverted electrodethat have different growth directions, so the orientation defects do not intrude into the display region

Liquid crystal display device and orientation processing method

A voltage corresponding to desired image data is applied to a ferroelectric liquid crystal having a spontaneous polarization at a predetermined cycle to rewrite the displayed image (period A), and then, all voltages applied to the ferroelectric liquid crystal are removed (timing C) to retain the displayed image before the removal (period B). A gate selection period (voltage application period to the ferroelectric liquid crystal) tbefore stopping the voltage application is set longer than a gate selection period (voltage application period to the ferroelectric liquid crystal) tin the normal display. Increasing the voltage application period to the ferroelectric liquid crystal provides a sufficient response of the liquid crystal during the gate selection period, thereby realizing high memory ability.

After rewriting the displayed image by applying a voltage corresponding to desired image data to a ferroelectric liquid crystal through TFTs at a predetermined cycle, the application of voltage to the ferroelectric liquid crystal is stopped, and the image displayed just before stopping the application of voltage is retained. In this memory display period, a gate-off voltage is applied to turn off the TFTs. In this memory display period, the emission intensity of a back-light is lowered compared to that in a normal display period. Before stopping the application of voltage to the ferroelectric liquid crystal, a voltage corresponding to an image to be displayed after stopping the application of voltage is applied. Before resuming the application of voltage corresponding to the image data to the ferroelectric liquid crystal, a voltage for causing all pixels to display black image is applied.

In a liquid crystal display device, one or a plurality of partition walls adhering to the two substrates are provided in a region between the adhesive member for sealing the peripheral portions of the two substrates and a display region located inside the adhesive member so as to reduce stress applied to the liquid crystal substance. Even when stress is applied to the liquid crystal substance in the peripheral portion of the substrate, the stress is reduced by the partition wall and is not transmitted to the display region on the opposite side of the partition wall. Therefore, even when a crack occurs in the peripheral portion of the substrate due to the stress, the propagation of the crack is stopped by the partition wall, and the crack does not enter the display region.

Liquid crystal display device and method of manufacturing liquid crystal display device for preventing defects in liquid crystal

There is provided a liquid crystal display including a panel using a liquid crystal material having spontaneous polarization, such as ferroelectroic liquid crystal (FLC); having a faster response time suitable to display dynamic images. The FLC has the disadvantage caused by the incomplete memory effect at during driving for displaying 'black' in several frames, where the light transmittance is preferably desired zero. The panel in the display are driven signals so that the driving signals are applied across the picture element, where the signals are positively or negatively offset to reference voltage of the panel.

In a liquid crystal display device which is constructed by sealing a liquid crystal having spontaneous polarization in an active matrix panel including a coloring member and displays an image on a frame by frame basis by repeating a data writing process and a data erasing process for the active matrix panel, the frequency in the data writing process is set at least twice higher than a frame frequency and the data writing process and the data erasing process are completed within one frame time so that time taken for transmission of light through the coloring member is not more than a half of one frame time. The coloring member is in a non-light-transmitting state during a period of not shorter than a half of one frame, and the blurred outline section of a moving image is reduced.

Liquid crystal display device and liquid crystal display method

The present invention provides a manufacturing method of a liquid crystal display device capable of achieving uniform alignment of monostable ferroelectric liquid crystal having spontaneous polarization, and provides the liquid crystal display device. The liquid crystal (monostable ferroelectric liquid crystal having spontaneous polarization) showing a phase sequence, either isotropic liquid phase-cholesteric phase-chiral smectic C phase, isotropic liquid phase-chiral nematic phase-chiral smectic C phase, or isotropic liquid phase-cholesteric phase-smectic A phase-chiral smectic C phase, from a high temperature side to a low temperature side, is sandwiched between two glass substrates having transparent electrodes and alignment films whose pretilt angle is not more than 2&#xb0; and rubbing directions are parallel. In an alignment treatment which is performed to obtain a monostable state after heating the liquid crystal, an electric field with electric field strength of not less than 2 V/&#x3bc;m is applied in the vicinity of the transition temperature from a higher temperature phase than chiral smectic C phase to the chiral smectic C phase.

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Kawasaki, Japan

Yoshinori Kiyota