摘要:
A display device includes a liquid crystal panel, a controller, a common driver and a segment driver. The common driver is powered by a high power supply voltage and outputs row driving waveforms having predetermined voltage levels, which are relatively high. The segment driver is powered by a low power supply voltage and outputs column driving waveforms having predetermined voltage levels, which are relatively low. By this construction, it is not necessary for both the segment and common drivers to be high withstand voltage integrated circuit devices.
摘要:
A liquid crystal display panel gray shade driving device comprises first circuitry for applying row signals represented by a set of orthonormal functions to a group of row electrodes throughout one frame by set sequential scanning for each of selecting periods, and second circuitry for sequentially carrying out a dot product computation between the set of orthonormal functions and a set of pixel data consisting of bits, and applying a column signal having a voltage level corresponding to a result of the computation to each of a group of column electrodes in synchronization with the set sequential scanning for each of the selecting periods. The first circuitry has a vertical driver for applying the row signal, by doubling the rate thereof, to the group of row electrodes and repeating the same set sequential scanning at least for two frames of previous and subsequent frames. The second circuitry has a frame memory for holding the pixel data in each frame while dividing it according to a significance of each bit and a dot product computing circuit for reading out the set of held pixel data per significance of each bit and carrying out the dot product computation to generate a column signal component corresponding to the significance of each bit. A horizontal driver divides the column signal components into a significant bit component and a less significant bit component, and distributes one component to the previous frame and the other to the subsequent frame to generate a column signal which is applied to the group of column electrodes.
摘要:
A display device includes a vertical driver for applying to row electrodes a set of row signals represented by a set of orthogonal functions supplied by an orthogonal function generator at each selection period by group-sequential scanning within one frame. A dot product processor successively carries out a dot product computation between the set of orthogonal functions and a set of pixel data. A horizontal driver applies to column electrodes column signals having voltage levels determined by the results of the dot product computation at each selection period in synchronization with the group-sequential scanning. A frame memory stores the pixel data for each frame in divided bit form. The dot product processor reads out the set of stored pixel data in divided bit form and executes the dot product computation to produce a column signal component for each respective bit. The horizontal driver arranges a plurality of column signal components corresponding to the respective bits subjected to either pulse modulation or frame-rate modulation within one frame period to produce the column signal that is applied to the column electrodes. A memory controller controls the writing of the pixel data into the frame memory. Bit data subjected to the pulse modulation are written to the frame memory for every frame, while bit data subjected to frame-rate modulation are selectively written to the frame memory only at frames specified by the frame-rate modulation.
摘要:
In order to prevent signal distortion using a multiple line selection driving technique when using pulse width modulation to achieve a half-tone display in a liquid crystal display panel, respective bits of column signals are arranged in a descending pulse width order and a voltage generating circuit is used to lower level differences in adjacent bits. An orthonormal function generating circuit generates a plurality of row signals to drive a group of row electrodes through a vertical driver. A dot product computation circuit computes a dot product of the orthonormal functions and pixel display data to generate a column signal in the above manner. A horizontal driver applies the column signal to a group of column electrodes. Pixel data is stored in a frame memory, each datum being represented by a series of bits corresponding to a gray scale. The dot product computation circuit divides the pixel data into the respective bits, and individually carries out the dot product computation for each bit. The horizontal driver arranges the column signal components in order of descending pulse width. A voltage level circuit lowers the voltage level between the column components to reduce distortion caused by the high switching speed between the components and the low response time of the liquid crystal material.
摘要:
A reflective liquid crystal display device comprises a transparent first substrate having formed thereon a transparent electrode, a first filter having a first color, and a second filte having a second color. A second substrate is disposed opposite and spaced-apart from the first substrate. A reflection layer is disposed on the second substrate. A polymer dispersed liquid crystal layer is disposed between the transparent electrode and the reflection layer and is formed by exposure to an ultraviolet ray in a preselected wavelength range. A ratio of a transmissivity of the first filter for the ultraviolet ray to a transmissivity of the second filter for the ultraviolet ray is 3.0 or less.
摘要:
A reflection type liquid crystal display device according to the present invention is constructed to include: a light modulation layer having a light scattering state changed when a voltage is applied between electrode faces; at least one kind of color separation layer arranged at the back of the liquid crystal; and a reflection layer arranged at the back of the color separation layer. The light modulation layer is a polymer network type polymer scattered liquid crystal layer or a phase conversion type liquid crystal layer, and the color separation mirror is a cholesteric liquid crystal polymer layer or a dielectric multi-layered thin film characterized to reflect a light within a predetermined wavelength range in the visible light region selectively. A reflection preventing layer and an ultraviolet ray cut-off layer are further arranged on the surfaces of the electrode faces.
摘要:
A reflection type liquid crystal display device comprises a pair of substrates having electrodes, a light scattering type liquid crystal layer interposed between the substrates, a reflection layer disposed over a rear surface of the light scattering type liquid crystal layer, and a light absorbing layer disposed over a rear surface of the reflection layer for absorbing a light passed through the reflection layer. The light scattering type liquid crystal layer changes into a scattering state or a transparent state in accordance with a change in a voltage level between the electrodes, and transmits 60% or more of incident light irrespective of the change in the voltage level between the electrodes. The reflection layer has a reflectivity within a range of 10 to 50% for reflecting a forward scattered light passed through the light scattering type liquid crystal layer.
摘要:
A reflective type liquid crystal display device has a first transparent substrate, a second transparent substrate, and a light scattering liquid crystal layer disposed between the first and second transparent substrates. A solar cell is disposed on the second transparent substrate. A portion of the solar cell comprises an active element for driving the light scattering liquid crystal layer.
摘要:
The liquid crystal display device is comprised of a matrix panel 1, a common driver 2 and a segment driver 3. A liquid crystal layer is interposed between rows of the scanning electrodes 4 and columns of signal electrodes 5. A frame memory 6 stores an inputted dot data each frame. An orthonormal signal generator 7 generates a set of orthonormal signals to sequentially feed the same in a desired combination pattern to the common driver 2 to concurrently drive a multiple of the scanning electrodes 4 to effect group sequential scanning according to the combination pattern. A dot product computation unit 8 executes dot product computation between a set of the dot data and the set of the orthonormal signals, the result of which is fed to the segment driver 3 to drive the columns of the signal electrodes 5. The group sequential scanning is repeated several times within one cycle to display a picture. The orthonormal signals are horizontally or vertically shifted to improve the quality of the displayed picture. Further, the multiple concurrent line number is optimized to balance the withstand voltage between the common driver 2 and the segment driver 3. Moreover, in the gray shading display by pulse-height modulation, a voltage pulse assigned to a virtual line of the scanning electrode is spread out to improve the gray shaded quality of the displayed picture.
摘要:
In a method of driving a bistable nematic dot-matrix liquid crystal display panel, from the facts that a write waveform contains a DC component and that liquid crystal molecules have not yet reached a stable state of anchoring force immediately after the end of writing but gradually become the stable state, it is considered that charges still remain in liquid crystal even at the time point when a COM electrode and a SEG electrode have become GND. Although the residual charges resulting from single writing cause no problem because its period is short, the residual charges after writing break down the bistable liquid crystal display panel as the number of rewriting increases. Immediately after a waveform for rewriting the bistable liquid crystal display panel was applied, an AC waveform of a voltage lower than the last pulse of a drive waveform was applied. Further, the voltage was allowed to gradually approach 0 V.