摘要:
In a plasma addressed liquid crystal display panel comprising a channel substrate, a cover sheet, a layer of twisted nematic liquid crystal material, an upper substrate, and an array of electrodes on the lower surface of the upper substrate, ##EQU1## where V.sub.x is the voltage that will turn a simple TN liquid crystal cell from the off state to X% transmissive in a normally black mode, d.sub.TD is the thickness of the cover sheet, d.sub.LC is the thickness of the liquid crystal layer, .epsilon..sub.TD is the dielectric constant of the cover sheet, .epsilon..sub..perp. is the perpendicular dielectric constant of the liquid crystal material, and .epsilon..sub..parallel. is the parallel dielectric constant of the liquid crystal material, and d.sub.LC .DELTA.n.sub.LC is in the range from about 0.4 to 0.5, where .DELTA.n.sub.LC is the difference in refractive indices for the liquid crystal material.
摘要:
A method and an apparatus reduce cross talk effects in electro-optical addressing structures. In a preferred embodiment, a flat panel liquid crystal display system (10) includes a layer (28) of frequency-sensitive liquid crystal material having a dielectric anisotropy that approaches zero for signal frequencies greater than a characteristic threshold frequency f.sub.th. The frequency-sensitive liquid crystal material is nonresponsive to components of signals with frequencies greater than the threshold frequency f.sub.th. A data driver (32) delivers inverted data signals (62) and conventional, noninverted data signals (64) to each of the multiple display elements (16) during successive first and second time intervals, respectively. As a result, the data driver generates cross talk having frequency components greater than the characteristic threshold frequency f.sub.th of the liquid crystal material. The liquid crystal material is not responsive to the high frequency cross talk, thereby substantially eliminating the cross talk effects.
摘要:
An electrode structure (100) for an addressing structure using an ionizable gaseous medium has a substrate (102) and a cover (126). A plurality of channel-defining portions (116, 118, 120, 122, 124) each extend from the substrate to the cover; each pair of adjacent channel-defining portions defines a plasma discharge channel (129, 131, 133, 135, 137) for the ionizable gaseous medium. An electrode (104, 106, 108, 110, 112) extends through each channel-defining portion so that the electrode has a surface exposed to each of the channels defined in part by the channel-defining portion. Each of the channel defining portions or walls separates each electrode from the cover. An addressing structure using the electrode structure of the invention ionizes the gas in each channel by driving the electrodes of the pair of adjacent channel-defining portions that define the channel.
摘要:
A flat panel apparatus for and a method of addressing data storage locations (80) employs a row-scanning electron beam (76) to address simultaneously a row (120) of such storage locations and thereby store data in and read data out of them. The storage locations are defined by the overlapping areas of multiple column electrodes (62) extending in a common direction on a first substrate (82) and rows addressed by the electron beam and extending in a common direction on a second substrate (54). A layer of dielectric material (52) separate the first and the second substrates, which are positioned face-to-face and spaced-apart with the direction of the addressed rows transverse to that of the column electrodes. The column electrodes receive data drive signals. The addressing apparatus is configured so that for each storage location secondary electrons emitted by the electron beam striking the location function as an electrical switch that changes between a conducting state and a nonconducting state in response to the presence of the electron beam. The secondary electrons function to either store data in or read data out of the storage location. If the storage location includes a layer (52) of material having electro-optic properties and receives incident image-carrying light, the secondary electrons function to select and store image data across the layer and thereby provide a display system having gray scale luminance.
摘要:
An electron beam addressed liquid crystal light modulator or "valve" (10) includes a liquid crystasl cell (40) having a target surface (45) which a writing electron beam (60a) and an erasing electron beam (60b) address to provide a display image. The writing electron beam and the erasing electron beam sequentially strike preselected locations on the target surface to cause an emission of secondary electrons and, thereby, develop an electrostatic potential at such preselected locations. A secondary electron collector electrode (66) positioned over and above the target surface collects in a uniform manner the secondary electrons emitted by all regions of the target surface. A collector electrode controller circuit (81) sequentially applied first and second potential differences between the target surface and the collector electrode in synchronism with the striking of the preselected locations by the respective writing and erasing beams. The first potential difference causes the collector electrode to collect a sufficient number of the secondary electrons to maintain the electrostatic potential at the preselected locations on the target surface. This causes the liquid crystal cell to transmit light in a first polarization sense. The second potential difference causes the collector electrode to collect a relatively small number of the secondary electrons. The remaining secondary electrons redistribute over the target surface and change the electrostatic potential at the preselected locations.
摘要:
An enchanced luminance field sequential color image display system having an image source for providing a sequence of monochrome images. The monochromatic light images are formed of first, second and third different spectral colors. A liquid crystal switching system having crossed color selective polarizers is used to transmit the second and third colors with a first direction of polarization and to transmit the first and third colors with an orthogonal direction of polarization. A liquid crystal retarder is used to rotate the direction of polarization of light incident from the crossed polarizers by ninety degrees when the retarder is in its OFF state and to transmit the light substantially unchanged when the retarder is in its ON state. The light is then coupled to an analyzing system which in one embodiment is a neutral polarizer that transmits either the second and third colors or the first and third colors, depending on the state of the liquid crystal retarder. In a second embodiment, the analyzing system is one or more color selective (pleochroic) polarizers that transmits both polarizations of the third color, while transmitting only one polarization of the first color or one polarization of the second color depending on the state of the retarder. By transmitting two of the three spectral colors in each of both directions of polarization through the retarder, a significant increase in display luminance is obtained.
摘要:
A method and an apparatus provide an optical switching system (10) which provides independent of viewing angle two system optical transmission states of substantially contaminant-free light. The system includes first and second light gates (12 and 12') of which each has associated therewith contaminant light intensity patterns (48 and 66) with points of local maxima (54, 56, 58, 60, 68, and 70) and local minima (62 and 72) in two system optical transmission states. The contaminant light intensity patterns are oriented so that the points of local maxima and minima of the contaminant light intensity patterns of one of the light gates generally align with the respective points of local minima and maxima of the contaminant light intensity patterns of the other light gate. The alignment of contaminant light intensity patterns blocks the transmission of contaminant light in two system optical transmission states, and thereby provides improved viewing angle performance.
摘要:
A PALC panel is operated by increasing the voltage between the channel electrodes to a firing voltage to create a plasma in the channel, reducing the voltage between the channel electrodes to a sustaining voltage to sustain the plasma for an interval during which a selected drive voltage is applied to the data drive electrode to establish an electric field in the layer of electro-optic material, and reducing the voltage between the channel electrodes to a bias voltage, which is insufficient to sustain the plasma but provides an electric field having a component parallel to the cover sheet in the layer of electro-optic material.
摘要:
An anode in a channel of a PALC display panel is composed of an electrically conductive core and a protective coating made of a material that is electrically conductive and is non-reactive with hydrogen.
摘要:
A plasma addressed liquid crystal display panel comprises a channel substrate having plasma channels in its upper surface thereof and an upper substrate over the upper surface of the channel substrate. A first polarizer is disposed over the upper surface of the channel substrate and transmits only light that is polarized in a first state. An electro-optic layer extends over the first polarizer and has a first condition in which it transmits light that is polarized in the first state without changing the state of polarization and a second condition in which it converts light that is polarized in the first state to a second state of polarization that is orthogonal to the first state. A second polarizer is over the electro-optic layer and transmits only light that is polarized in the second state. When the electro-optic layer is in the first condition, the second polarizer blocks the light that is transmitted by the first polarizer, whereas when the electro-optic layer is in the second condition, the second polarizer passes the light that is transmitted by the first polarizer.