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146 results about "OCB mode" patented technology
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OCB mode (Offset Codebook Mode) is an authenticated encryption mode of operation for cryptographic block ciphers. OCB mode was designed by Phillip Rogaway, who credits Mihir Bellare, John Black, and Ted Krovetz with assistance and comments on the designs. It is based on the authenticated encryption mode IAPM due to Charanjit S. Jutla.
Liquid crystal display device
InactiveUS6952194B1Large-sized displayImprove accuracyCathode-ray tube indicatorsInput/output processes for data processingImage resolutionActive matrix
Owner:SEMICON ENERGY LAB CO LTD
Liquid crystal display device and method for driving the same
InactiveUS20070132709A1Increase currentInhibit transferStatic indicating devicesScan lineEngineering
Occurrence of insufficient writing to a liquid crystal display element is prevented in the liquid crystal display device which causes a backlight to illuminate only while the liquid crystal display element responds to the display data. A liquid crystal display device has a liquid crystal display panel using an OCB mode liquid crystal, divides a field period into a black writing period, a display data writing period, and a display data hold period, writes black data for preventing transferring from the bend alignment to the spray alignment in the black writing period, writes display data in the display data writing period, and lights a backlight during a part of the display data hold period, wherein a gate driver makes periods during each of which each of gate signals corresponding to each of the scan lines are turned on are same to each other when a source driver writes the display data in the liquid crystal display element, and makes periods during each of which each of gate signals corresponding to each of the scan lines are turned on longer than a period during which display data is written for a line when the source driver writes black data for preventing transferring from the bend alignment to the spray alignment.
Owner:TOSHIBA MATSUSHITA DISPLAY TECH
Compensating film for a liquid crystal display and an OCB mode liquid crystal display incorporating the compensating film
InactiveUS6124913AGood compensationSet freeLiquid crystal compositionsDiffusing elementsColor compensationFilm plane
As a compensator for use in an OCB mode liquid crystal display there is provided a compensating film capable of making color compensation and attaining such a viewing angle expansion as has not been attainable heretofore. A compensating film for a liquid crystal display, constituted by at least one layer of a compensating film to be used in an OCB mode liquid crystal display, the compensating film being formed by a discotic liquid crystalline material having a fixed orientation form of a discotic liquid crystal, the compensating film being disposed between a driving liquid crystal cell and a pair of upper and lower polarizing plates, and the orientation form being a hybrid orientation in which the angle between discotic liquid crystal directors near the upper interface of the film and the film plane and the angle between discotic liquid crystal directors near the lower interface of the film and film plane are different from each other.
Owner:NIPPON MITSUBISHI OIL CORP
Cryptographic apparatus for supporting multiple modes
ActiveUS7509501B2Simple circuit configurationEncryption apparatus with shift registers/memoriesUser identity/authority verificationZero paddingCommunications system
The present invention relates to a cryptographic apparatus for encrypting data stored in a memory. The cryptographic apparatus of the present invention operates in the ECB, CBC, CBC-MAC, counter and OCB modes using small and simple elements. The cryptographic apparatus minimizes data communication between CPU and the cryptographic apparatus to improve the performance of the communication system. On the other hand, the input buffer and output buffer of the cryptographic apparatus are configured to store at least two blocks respectively, so that the performance of the cryptographic apparatus is maximized. Furthermore, the cryptographic apparatus supports zero-padding, so that the process of the CPU is minimized.
Owner:SAMSUNG ELECTRONICS CO LTD
Liquid crystal display device and method of driving liquid crystal display device
InactiveUS20060007207A1Minimum brightnessCathode-ray tube indicatorsInput/output processes for data processingDisplay deviceEngineering
A liquid crystal display device includes a liquid crystal display panel having source signal lines and gate signal lines arranged in matrix form and liquid crystal display elements using OCB mode liquid crystal, the liquid crystal display elements being provided at intersections between the source signal lines and gate signal lines; a gate driver that supplies a gate signal to said gate signal lines; a source driver that supplies a voltage corresponding to gradation of display data to said source signal lines during a display period; temperature detection means of detecting temperature; and correcting means of correcting display data for generating the source signal to display data according to the detected temperature, wherein the source signal is generated based on the corrected display data.
Owner:TOSHIBA MATSUSHITA DISPLAY TECH
Liquid crystal display device
InactiveUS20050007331A1Large-sized displayImprove accuracyLiquid crystal compositionsCathode-ray tube indicatorsActive matrixTime ratio
An object of the present invention is to provide a small-sized active matrix type liquid crystal display device that may achieve large-sized display, high precision, high resolution and multi-gray scales. According to the present invention, gray scale display is performed by combining time ratio gray scale and voltage gray scale in a liquid crystal display device which performs display in OCB mode. In doing so, one frame is divided into subframes corresponding to the number of bit for the time ratio gray scale. Initialize voltage is applied onto the liquid crystal upon display of a subframe.
Owner:SEMICON ENERGY LAB CO LTD
Liquid crystal display device having OCB mode and method of driving the same
InactiveUS20060125715A1Reduce ambiguityIncrease brightnessCathode-ray tube indicatorsNon-linear opticsDc dc converterOptical transmittance
A liquid crystal display device (LCD) which applies a high voltage for carrying out a bend transition of an optically compensated birefringence (OCB) liquid crystal as a reset voltage to a common electrode of the OCB liquid crystal in the LCD having an OCB mode, and a method of driving the same are provided. In the OCB mode LCD, a voltage of a DC-DC converter is applied to a common electrode to reset the OCB liquid crystal at an initial stage of every frame or before applying data to each pixel. In addition, when one frame is divided into red, green and blue fields, and sequentially driven, a voltage of the DC-DC converter is applied to the common electrode to reset the OCB liquid crystal before each field begins. The DC-DC converter applies a voltage of 15V to 30V to the common electrode. An optical transmittance of the liquid crystal at the time of reset becomes zero (black state). Accordingly, a blurring effect can be removed while a reset time can be decreased, thereby increasing the brightness.
Owner:SAMSUNG MOBILE DISPLAY CO LTD
Liquid crystal display device
InactiveUS20050024309A1Large-sized displayImprove accuracySolid-state devicesCathode-ray tube indicatorsActive matrixTime ratio
An object of the present invention is to provide a small-sized active matrix type liquid crystal display device that may achieve large-sized display, high precision, high resolution and multi-gray scales. According to the present invention, gray scale display is performed by combining time ratio gray scale and voltage gray scale in a liquid crystal display device which performs display in OCB mode. In doing so, one frame is divided into subframes corresponding to the number of bit for the time ratio gray scale. Initialize voltage is applied onto the liquid crystal upon display of a subframe.
Owner:SEMICON ENERGY LAB CO LTD
LCD for speeding initial bend state, driver and method thereof
ActiveUS7019728B2Quick transitionStatic indicating devicesNon-linear opticsExternal biasDisplay device
The present invention is directed to a liquid crystal display device and a method for driving the same for a fast transition into a bend state at initial operation such as immediately after power is inputted in a liquid display device with an OCB mode. According to one feature of the present invention, as power is inputted, a timing controller controls to output at least one of a gate voltage for a scan signal, a data voltage for a picture signal, and a driving voltage for a backlight by outputting a first switching signal to a switching unit, and controls to output one of an external bias voltage and a common electrode voltage by outputting a second switching signal to the switching unit so that fast transition into bend state of liquid crystal arranged in a LCD panel is accomplished. As a result, by applying a voltage of less level than that of the typical common electrode voltage to the LCD panel, as DC voltage of at least 10 volt to 20 volt is applicable to a common electrode, time for transition into bend state can be reduced at initial operation of the liquid crystal display device using the LCD panel with OCB mode.
Owner:SAMSUNG DISPLAY CO LTD
Liquid crystal display device having OCB mode liquid crystal layer and method of fabricating the same
InactiveUS20060114378A1Sufficient bend transition without degrading a display qualityNon-linear opticsEngineeringOCB mode
A liquid crystal display device and a method of fabricating the same are provided. The liquid crystal display device includes: a lower substrate having an opening region and a non-opening region adjacent to the opening region; a pixel electrode located on the opening region; an upper substrate located above the lower substrate and having an opposite surface facing the lower substrate; a protrusion type light shielding layer pattern located on a portion of the opposite surface corresponding to the non-opening region; an opposite electrode located on the protrusion type light shielding layer pattern; and an OCB mode liquid crystal layer located between the pixel electrode and the opposite electrode.
Owner:SAMSUNG DISPLAY CO LTD
Ocb mode liquid crystal display and a driving method of the same
A liquid crystal display includes a TFT array panel, a color filter panel, a liquid crystal layer in an OCB mode, a pair of compensation films provided on outer surfaces of the TFT array panel and the color filter panel, a pair of polarization films provided on outer surfaces of the compensation films, and so on. When the wavelength dispersion of the liquid crystal layer is larger than the wavelength dispersion of the first and the second compensation films, the cell gap on the red pixel area>the cell gap on the green pixel area>the cell gap on the blue pixel area. On the contrary, when the wavelength dispersion of the liquid crystal layer is smaller than the wavelength dispersion of the first and the second compensation films, the cell gap on the red pixel area<the cell gap on the green pixel area<the cell gap on the blue pixel area.
Owner:SAMSUNG DISPLAY CO LTD
Liquid crystal display and method of manufacture
InactiveUS20020085154A1Wide viewing angleMaximum reliabilityNon-linear opticsActive matrixEngineering
An active matrix type liquid crystal display composed of a liquid crystal cell 124 is described. In the liquid crystal cell 124, liquid crystals at the upper and lower interfaces of a liquid crystal layer 122 inserted between an array substrate 106 having pixel electrodes 128 and an opposed substrate 105 having an opposed electrode 127 have pretilt angles opposite to each other in a positive / negative sense and are aligned in parallel with each other, forming a spray alignment. This liquid crystal display performs displaying by bend-aligning such a liquid crystal cell 124. The pixel electrodes 128 are formed on a flattening film 100 for covering switching elements 123 or wiring electrodes flat. With this arrangement, a spray to bend alignment transition can be reliably, easily caused in a short time within the liquid crystal cell pixels, so that an OCB mode liquid crystal display free from alignment defects and having high picture quality can be achieved.
Owner:JAPAN DISPLAY CENT INC
Liquid crystal display using liquid crystal with bend alignment and driving method thereof
InactiveUS6927825B1Fast response timeLiquid crystal compositionsStatic indicating devicesActive matrixEngineering
When a transition voltage, which is higher than a display voltage for image display, is applied to liquid crystal, the liquid crystal can transition to a bend alignment. Therefore, by applying a transition voltage to liquid crystal prior to image display period only for a transition time which depends on a transition voltage so as to cause a bend transition in the liquid crystal, an OCB mode LCD with a high speed response can be obtained. An interval d between pixel regions is set to be less than, for example, a transition distance of 5 μm, so that a bend transition expands over inter-pixel regions to thereby achieve a bend transition all over the display region. In an active matrix type LCD, a electrical field is caused to be generated between a common electrode and data lines or gate lines disposed between pixel electrodes due to application of a transition voltage to the common electrode, thereby obtaining a bent transition over the entire surface of the display screen. Further, a pretilt angle set by an alignment film is determined to be 1.2° or more, such that a great number of transition sources for causing a bend transition are generated to thereby secure a high speed bend transition. Also, the pretilt angle is set to be 3° or less for accelerating a response time in a bend alignment.
Owner:SANYO ELECTRIC CO LTD
Liquid crystal display device
InactiveUS20050052392A1Large-sized displayImprove accuracySolid-state devicesCathode-ray tube indicatorsActive matrixTime ratio
An object of the present invention is to provide a small-sized active matrix type liquid crystal display device that may achieve large-sized display, high precision, high resolution and multi-gray scales. According to the present invention, gray scale display is performed by combining time ratio gray scale and voltage gray scale in a liquid crystal display device which performs display in OCB mode. In doing so, one frame is divided into subframes corresponding to the number of bit for the time ratio gray scale. Initialize voltage is applied onto the liquid crystal upon display of a subframe.
Owner:SEMICON ENERGY LAB CO LTD
Liquid crystal display
InactiveUS20060007096A1Display unevenness can be preventedQuick changeCathode-ray tube indicatorsNon-linear opticsOCB modeEngineering
Owner:JAPAN DISPLAY CENTRAL CO LTD
Liquid crystal display device and method of fabricating the same
A liquid crystal display device (LCD) and method of fabricating the same are provided, in which in an OCB mode LCD, an edge portion of a first electrode is formed with a taper angle of not less than approximately 25° and less than 90°, thus an electric field in the edge portion of the first electrode becomes nonuniform so that a transitional nucleus is easily created and liquid crystals are readily transitioned to a bend phase at a low transition voltage. As a result, the phase transition of the liquid crystals can be easily controlled.
Owner:SAMSUNG MOBILE DISPLAY CO LTD
Liquid crystal display device
A liquid crystal display device having a reflective part and a transmissive part in each of a plurality of pixels which are arrayed in a matrix, includes a liquid crystal display panel which is configured such that a liquid crystal layer is held between a pair of substrates, and to which an OCB mode is applied, and a pair of optical elements which are disposed on outer surfaces of the liquid crystal display panel, respectively, and optically compensate a retardation of the liquid crystal layer in a predetermined display state in which a voltage is applied to the liquid crystal layer, wherein the optical element is configured to include a circular polarization element including a polarizer and a first retardation plate which is disposed between the polarizer and the liquid crystal display panel and imparts a retardation of 1 / 4 wavelength, and a second retardation plate which is disposed between the circular polarization element and the liquid crystal layer, and has refractive index anisotropy with a major axis being inclined to a normal line, and the optical element has a retardation in a thickness direction thereof.
Owner:JAPAN DISPLAY CENTRAL CO LTD
Liquid crystal display device and method of driving liquid crystal display device
The liquid crystal display device includes a liquid crystal display panel provided with source signal lines and gate signal lines arranged in matrix form and liquid crystal display elements using OCB mode liquid crystal provided at intersections between the source signal lines and gate signal lines, a gate driver which supplies a gate signal to the gate signal lines and a source driver which supplies a voltage corresponding to gradation of the display data to the source signal lines during a display period and supplies a voltage to prevent counter-transfer to the source signal lines during a counter-transfer prevention drive period, and the source driver supplies a voltage lower by a predetermined value than the voltage corresponding to the black color as the voltage to prevent counter-transfer.
Owner:TOSHIBA MATSUSHITA DISPLAY TECH
Liquid crystal display
InactiveCN1800936ATransfer is fast and stableIncrease viewing angleNon-linear opticsEngineeringDiscotic liquid crystal
To provide a liquid crystal display device capable of generating the transition of a liquid crystal layer from a splay alignment state to a bend alignment state quickly and stably without applying a high driving voltage.The liquid crystal display device is provided with a liquid crystal panel 2 having: a pair of substrates 3, 4 , which are arranged oppositely to each other and in which electrodes 19, 25 and alignment layers 21, 26 are formed on respective counter surfaces thereof; an OCB mode liquid crystal layer 5 in which a nematic liquid crystal sealed in between the pair of substrates 3, 4 is splay aligned with the alignment layers 21, 26 and the splay aligned nematic liquid crystal is subjected to the transition to the bend aligned state with the driving voltage applied between the electrodes 19, 25; and spacers 6 arranged inside the liquid crystal layer 5 and retaining a gap between the pair of mutually opposing substrates 3, 4 uniform. The spacers 6 are subjected to a surface treatment for accelerating the transition of the liquid crystal layer 5 from the splay aligned state to the bend aligned state.
Owner:ALPS ALPINE CO LTD
Liquid crystal display device
InactiveUS20050057474A1Large-sized displayImprove accuracySolid-state devicesSemiconductor/solid-state device manufacturingActive matrixTime ratio
An object of the present invention is to provide a small-sized active matrix type liquid crystal display device that may achieve large-sized display, high precision, high resolution and multi-gray scales. According to the present invention, gray scale display is performed by combining time ratio gray scale and voltage gray scale in a liquid crystal display device which performs display in OCB mode. In doing so, one frame is divided into subframes corresponding to the number of bit for the time ratio gray scale. Initialize voltage is applied onto the liquid crystal upon display of a subframe.
Owner:SEMICON ENERGY LAB CO LTD
Optically compensated bend mode liquid crystal display devices
InactiveUS20090033821A1Static indicating devicesNon-linear opticsMaterials scienceElectrical and Electronics engineering
An OCB mode liquid crystal display device is provided. The OCB mode liquid crystal display device comprises a first substrate, a second substrate and a liquid crystal layer interposed therebetween. The first substrate and the second substrate are disposed oppositely to each other. The device further comprises a first pixel electrode disposed on the first substrate, a second pixel electrode disposed on the first substrate and spaced apart from the first pixel electrode by a distance. The first pixel electrode and second pixel electrode are alternately arranged. The device further comprises a first alignment layer disposed on the first substrate to cover the first pixel electrode and the second pixel electrode, a common electrode disposed on the second substrate, and a second alignment layer disposed on the second substrate covering the common electrode.
Owner:IND TECH RES INST
LCD for speeding initial bend state, driver and method thereof
InactiveUS20060114215A1Quick transitionStatic indicating devicesNon-linear opticsExternal biasDisplay device
Owner:LEE CHANG HUN +4
Liquid crystal display device
InactiveUS20060012590A1Fast transferQuickly transfer alignment stateCathode-ray tube indicatorsNon-linear opticsHeating timeEngineering
A liquid crystal display device comprises a liquid crystal display panel including a liquid crystal layer for a display in an OCB mode, a heating unit which heats the liquid crystal display panel, a temperature detecting unit for detecting a temperature of the liquid crystal display panel, a time measuring unit which measures a heating time that the heating unit has operated, and a transfer drive circuit which applies a transfer drive voltage to the liquid crystal layer to transfer the alignment state of liquid crystal molecules from a splay alignment to a bend alignment in advance. The transfer drive circuit is configured to determine a transfer time as an application period of the transfer drive voltage on the basis of a relationship between the heating time and temperature which are obtained from the time measuring unit and temperature detecting unit at a desired timing.
Owner:JAPAN DISPLAY CENT INC
Liquid crystal display and method of manufacture
InactiveUS6710832B2Wide viewing angleMaximum reliabilityStatic indicating devicesNon-linear opticsActive matrixEngineering
An active matrix type liquid crystal display composed of a liquid crystal cell 124 is described. In the liquid crystal cell 124, liquid crystals at the upper and lower interfaces of a liquid crystal layer 122 inserted between an array substrate 106 having pixel electrodes 128 and an opposed substrate 105 having an opposed electrode 127 have pretilt angles opposite to each other in a positive / negative sense and are aligned in parallel with each other, forming a spray alignment. This liquid crystal display performs displaying by bend-aligning such a liquid crystal cell 124. The pixel electrodes 128 are formed on a flattening film 100 for covering switching elements 123 or wiring electrodes flat. With this arrangement, a spray to bend alignment transition can be reliably, easily caused in a short time within the liquid crystal cell pixels, so that an OCB mode liquid crystal display free from alignment defects and having high picture quality can be achieved.
Owner:JAPAN DISPLAY CENTRAL CO LTD
Liquid display device and method for driving liquid crystal display device
A liquid crystal display device includes a liquid crystal display panel having source signal lines and gate signal lines arranged in matrix form and liquid crystal display elements using OCB mode liquid crystal, the liquid crystal display elements being provided at intersections between the source signal lines and gate signal lines; a gate driver that supplies a gate signal to said gate signal lines; a source driver that supplies a voltage corresponding to gradation of display data to said source signal lines during a display period; temperature detection means of detecting temperature; and correcting means of correcting display data for generating the source signal to display data according to the detected temperature, wherein the source signal is generated based on the corrected display data.
Owner:JAPAN DISPLAY CENTRAL CO LTD
Liquid crystal display and driving method thereof
InactiveUS20070115235A1Drive stabilitySecuring drive stabilityStatic indicating devicesNon-linear opticsScan lineData signal
Disclosed is a liquid crystal display (LCD) wherein driving stability is secured. The LCD includes Optically Compensated Birefringence (OCB) mode liquid crystal cells formed where a data line and a scan line cross over within a display region of an LCD panel, a panel driver for driving the data and the scan lines, and OCB mode dummy liquid crystal cells formed within a non-display region of the LCD panel to surround the liquid crystal cells. Liquid crystal in each of the dummy liquid crystal cells sustains a bend state when the liquid crystal cells in the display region are driven corresponding to a data signal applied from the data line.
Owner:SAMSUNG DISPLAY CO LTD
Transflective liquid crystal display device
A transflective liquid crystal display device includes a first and a second substrates, a liquid crystal layer, and a plurality of reflective electrodes and transparent electrodes. The liquid crystal layer is interposed between the first and the second substrates and functions in an OCB mode. The reflective electrode and the transparent electrode in one picture element are spaced apart from each other to produce a transverse electric field when a voltage is applied across the liquid crystal layer.
Owner:WINTEK CORP
Liquid crystal display device, display control method and display control apparatus
InactiveUS20070024553A1Avoid it happening againStatic indicating devicesEngineeringThreshold voltage
A liquid crystal display device comprises an OCB-mode liquid crystal display panel including a liquid crystal layer in which the alignment state of liquid crystal molecules is transitioned in advance from a splay alignment to a bend alignment, and a display control section which applies a liquid crystal drive voltage to the liquid crystal layer according to a video signal. The display control section is configured to detect the application environment of the liquid crystal display panel and determine a minimum value of the liquid crystal drive voltage based on a phase-transition threshold voltage which causes energy of the splay alignment and energy of the bend alignment to be balanced with each other in the detected application environment.
Owner:TOSHIBA MATSUSHITA DISPLAY TECH
Liquid crystal display device
InactiveUS20070273634A1Shorten the timeStatic indicating devicesNon-linear opticsPixel arrayElectric field
A liquid crystal display device of an OCB mode includes a liquid crystal layer held between an array substrate and a counter-substrate, and a display section composed of display pixels arrayed in a matrix. The array substrate includes pixel electrodes which are disposed in association with the display pixels. The counter-substrate includes a counter-electrode opposed to the pixel electrodes. The substrates include a pair of alignment films which are disposed on the pixel electrodes and the counter-electrode, respectively, and are subjected to rubbing treatment to control an alignment state of liquid crystal molecules included in the layer. A transition-nucleus formation section, which generates an electric field for transitioning the alignment state of the liquid crystal molecules included in the layer from a non-display state to a display state, is provided on a terminal-end side of a rubbing direction of each of the alignment films in each of the display pixels.
Owner:JAPAN DISPLAY CENT INC
Liquid crystal display and its driving method
A frequency converting section (101), which is included in a liquid crystal display apparatus, generates an output video signal by inserting one non-image signal, which is to be concurrently written into pixels on L (L is an integer equal to or greater than two) gate lines of the liquid crystal panel, for one line, between image signals composing an input video signal, for corresponding L lines, and adjusting a number of horizontal scanning periods of the output video signal in a vertical blanking period so that a number of horizontal scanning periods composing one frame period is (L+1)x(2N+1) (N is an integer). Thus, when anti-back-transition driving is performed using a liquid crystal panel in OCB mode, it is possible to minimize increase in a driving frequency, prevent irregularity of brightness caused by AC driving of the liquid crystal panel, and reduce a cost.
Owner:PANASONIC CORP
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