Liquid crystal display device and method of manufacturing such
AssigneeU.S. Philips Corporation
InventorsPeter Van De Witte, Michael Geoffrey Pitt
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Abstract
In a method of manufacturing a liquid crystal device including a layer having a fixed cholesteric order, the patterned layer is manufactured by providing a layer comprising polymerizable cholesterically ordered material and a compound convertible by means of radiation from a non-converted to converted state. The pitch of the cholesterically ordered material is influenced by the compound in its converted state to a different extent than in its converted state. The polymerizable layer is then irradiated pattern-wise thus creating regions of different pitch. The irradiated layer is then polymerized and/or cross-linked to fix the cholesteric order thus obtained.
Claims19
A method of manufacturing a liquid crystal display device comprising a liquid crystal layer dispersed between a first and a second substrate, the first substrate comprising a patterned layer of a polymerized material having a fixed cholesteric order wherein the axis of the molecular helix extends transversely to the patterned layer and the patterned layer has at least a first and a second region in which the pitch of the molecular helix is mutually different, in which method the patterned layer of a polymerized material having a fixed cholesteric order is manufactured in accordance with a method comprising the steps of:
- a. providing a layer of a polymerizable and/or crosslinkable cholesterically ordered material comprising a quantity of a convertible compound which in its non-converted and in its converted state determines the pitch of the cholesterically ordered material to a different extent, the conversion of said compound being inducable by radiation,
- b. irradiating the layer in accordance with a desired pattern so that at least in a first region the convertible compound is converted to a different extent than in a second region,
- c. polymerizing and/or crosslinking the irradiated polymerizable and/or crosslinkable cholesterically ordered material to form a three-dimensional polymerized cholesterically ordered material in which the cholesteric order is fixed.
A method of manufacturing a liquid crystal display device comprising a layer of a polymerized and/or crosslinked material having a fixed cholesteric order wherein the axis of the molecular helix extends transversely to the layer and the pitch of the helix has a gradient in the direction of said axis, in which method the layer of polymerized and/or crosslinked cholesterically ordered material is manufactured in accordance with a method comprising the steps of:
- a. providing a layer of a polymerizable and/or crosslinkable cholesterically ordered material comprising a quantity of a convertible compound which in its non-converted and in its converted state determines the pitch of the cholesterically ordered material to a different extent, the conversion of said compound being inducable by radiation,
- b. irradiating the layer thus converting, at least partially, the convertible compound to its converted state,
- c. polymerizing and/or crosslinking the irradiated polymerizable and/or crosslinkable cholesterically ordered material to form a three-dimensional polymerized and/or crosslinked cholesterically ordered material in which the cholesteric order is fixed,
- wherein the absorption of the polymerizable and/or cross-linkable layer and the intensity of the radiation used in step b are selected such that the radiation is substantially absorbed by the polymerizable and/or cross-linkable layer, creating, transversely to the layer, a gradient in the pitch of the molecular helix.
A liquid crystal display device comprising a layer of polymerized cholesterically ordered material obtainable by a method as claimed in any one of the preceding claims.
A liquid crystal display device comprising a liquid crystal layer dispersed between a first and a second substrate, the first substrate comprising a patterned layer of a polymerized and/or cross-linked material having a fixed cholesteric order wherein the axis of the molecular helix extends transversely to the patterned layer, wherein the patterned layer comprises a quantity of a convertible compound which in its non-converted and in its converted state determines the pitch of the cholesterically ordered material to a different extent, the conversion being inducable by radiation and wherein the patterned layer has at least a first and a second region in which the pitch of the molecular helix is mutually different.
A reflective active matrix liquid crystal display device comprising a liquid crystal layer dispersed between an active and a passive substrate plate, the active substrate plate being present on the side opposite the viewing side and comprising a plurality of optically transparent pixel electrodes and a plurality of active switching elements for controlling the voltage supplied to said pixel electrodes, which switching elements are spatially separated from, positioned subjacent and electrically connected to said plurality of pixel electrodes, wherein the space separating the switching elements and the pixel electrodes is filled with an electrically insulating color selection layer which selectively reflects light of particular wavelengths and renders the switching elements invisible to the light reflected.
Dependencies are inferred from the claim text.