Abstract: An optical film in which a function of a brightness enhancement film is maintained and variations in brightness and chromaticity within a film plane are suppressed is provided. An optical film is a laminate of an absorptive dichroic polarizing plate and a brightness enhancement film. A maximum chromaticity difference &Dgr;xy(max) of in-plane transmitted light is 0.008 or smaller after the optical film is attached to a glass plate and allowed to stand at 70° C. for 120 hours. The brightness enhancement film includes a layer having a circularly polarized light separating function, and a quarter wavelength plate. The quarter wavelength plate is a film showing an in-plane retardation (&Dgr;nd) satisfying &Dgr;nd(450 nm)/&Dgr;nd(550 nm)<1.02 or a film containing a polymer having a photoelastic coefficient of 40×10−12 m2/N or smaller.

Abstract: There is provided an illuminator having a planar light source unit having reflectance of from 50 to 90% with respect to light in a state in which the light is emitted from a light source provided separately from the planar light source and incident on the planar light source unit, and a reflective type polarizer disposed on a light exit side of the planar light source unit so that a reflected light component and a transmitted light component of polarized light can be obtained from natural light incident on the reflective type polarizer. There is provided a liquid-crystal display device having an illuminator defined above, and a liquid-crystal display panel disposed on an upper side of the reflective type polarizer in the illuminator.

Abstract: There is provided an optical element having: a laminate including a reflective type polarizer for separating incident light into polarized light components through reflection and transmission, and a dichromatic polarizer, wherein a variation of hue between two points calculated by the expression: {(x2−x1)2+(y2−y1)2} is not larger than 0.06 when x1 and y1 express a hue at a point with a predetermined elevation angle and any azimuth angle, and x2 and y2 express a hue at another point with the same elevation angle and a changed azimuth angle in the case where transmitted light is obliquely viewed in the condition that the laminate is disposed on a planar light source so that the reflective type polarizer is located in an inner side. An illuminator having the above planar light source and laminate and including a reflection layers on its rear surface side, is disposed behind a liquid crystal cell.

Abstract: A liquid crystal orientation film, which is formed of a liquid crystal polymer, having a satisfactory orientation property is obtained by a method for manufacturing a liquid crystal orientation film, comprising the steps; coating a polymerizable liquid crystal monomer on an orientation substrate; orienting said polymerizable liquid crystal monomer in a state of liquid crystal; polymerizing said polymerizable liquid crystal monomer to form a liquid crystal orientation layer (1); coating a liquid crystal polymer on said liquid crystal orientation layer (1); and orienting said liquid crystal polymer in a state of liquid crystal to form a liquid crystal orientation layer (2).

Abstract: There is provided an optical element having: a laminate including a reflective type polarizer for separating incident light into polarized light components through reflection and transmission, and a dichromatic polarizer, wherein a variation of hue between two points calculated by the expression: {square root}{(x2−x1)2+(y2−y1)2} is not larger than 0.06 when x1 and y1 express a hue at a point with a predetermined elevation angle and any azimuth angle, and x2 and y2 express a hue at another point with the same elevation angle and a changed azimuth angle in the case where transmitted light is obliquely viewed in the condition that the laminate is disposed on a planar light source so that the reflective type polarizer is located in an inner side.

Abstract: A process for producing an optical element which comprises a polymeric liquid crystal layer having a helically twisted molecular structure and has satisfactory thickness precision and satisfactory optical properties. The process comprises applying a mixed solution containing a polymerizable nematic liquid crystal compound and a polymerizable chiral reagent to an oriented substrate, followed by drying, to orient the liquid crystal compound; and irradiating the mixed solution applied with radiation from the oriented substrate side while maintaining the mixed solution in contact with a gas comprising oxygen to thereby polymerize and cure the mixed solution.

Abstract: There is provided a polarizing member having a sheet-like member formed so that linearly polarized light can be obtained as transmitted light through the sheet-like member after natural light is incident on a rear surface of the sheet-like member, wherein the sheet-like member exhibits a transmittance difference of not larger than 6% between transmitted light components within a 20 nm-wide wavelength region in a transmission spectrum of light in a wavelength range of from 520 to 640 nm when natural light is incident on the sheet-like member at any angle ranging from an angle viewing from a line normal to a surface of the sheet-like member to an elevation angle of 80 degrees. There is provided an illuminator having a planar light source including a reflection layer on a rear surface side of the planar light source, and a polarizing member defined above and disposed on a front surface side of the planar light source.

Abstract: An optical film having excellent light utilization efficiency and high brightness, and a liquid crystal display using the optical film. The optical film is formed by laminating integrally a brightness enhancement film (A) that separates natural light into transmitted light and reflected light and a collimating film (B) having an uneven portion on a surface thereof. Since an air interface is eliminated by the integral lamination of the brightness enhancement film and the collimating film, stray light is reduced, and the brightness enhancement film has an improved efficiency in reflecting and polarizing light; thereby, enhancing the brightness.

Abstract: There is provided an illuminator having a planar light source unit having reflectance of from 50 to 90% with respect to light in a state in which the light is emitted from a light source provided separately from the planar light source and incident on the planar light source unit, and a reflective type polarizer disposed on a light exit side of the planar light source unit so that a reflected light component and a transmitted light component of polarized light can be obtained from natural light incident on the reflective type polarizer. There is provided a liquid-crystal display device having an illuminator defined above, and a liquid-crystal display panel disposed on an upper side of the reflective type polarizer in the illuminator.

Abstract: A cholesteric liquid crystal layer has a helical pitch changing in the thickness direction and shows circular dichroism over a wavelength region having a width of at least 50 nm and including a wavelength of 520 nm, wherein the linearly polarized light obtained through a quarter-wavelength plate has a maximum degree of polarization at a wavelength not longer than 520 nm, or the degree of polarization thereof in a wavelength region on the shorter-wavelength side of 520 nm is higher than that in a wavelength region on the longer-wavelength side of 520 nm. The optical element comprises a multilayer structure composed of the cholesteric liquid crystal layer and at least one optical layer superposed thereon which is a retardation compensating plate, a polarizing plate, a light conductive plate, or a quarter-wavelength plate having an Nz of −0.8 to −2.0 and disposed on the longer-helical pitch side of the liquid crystal layer.

Abstract: A polarizing member is constituted by an absorption type polarizing film, and one polymer material layer or two or more polymer material layers provided on one or both of opposite surfaces of the absorption type polarizing film, wherein each polymer material layer does not have any extra ordinary refractive index area with a length not smaller than 20 &mgr;m and does not have two or more extraordinary refractive index areas with a length of from 0.5 to 20 &mgr;m in a region of 50 &mgr;m-radius. An optical member is constituted by a laminate at least having the polarizing member, and a reflection type polarizing plate. A liquid-crystal display device is constituted by either of the polarizing member and the optical member, and a liquid-crystal cell, wherein either of the polarizing member and the optical member is provided on one or both of opposite sides of the liquid-crystal cell.

Abstract: Disclosed are a polarizer comprising a circularly polarized light separation layer in which two or more cholesteric liquid crystal polymer layers are laminated with each other in a close contact state in a long-short order based on a center wavelength of reflected light, said circularly polarized light separation layer changing in helical pitch in the direction of thickness, a retardation layer arranged on the long-wavelength side of said center wavelength, and a polarizing plate containing a dichroic substance and disposed on the retardation layer, as so desired; a lighting device in which a surface light source is arranged on the circularly polarized light separation layer side of said polarizer; and a liquid crystal display in which said polarizer or said lighting device is arranged on the visual back face side of a liquid crystal cell, directing the retardation layer side thereof to the liquid crystal cell.

Abstract: A polarizing member has a reflection type polarizing plate capable of separating natural incident light into reflected light and transmitted light to thereby obtain polarized transmitted light, and a fine concave-convex structure disposed on a single surface of the reflection type polarizing plate. The fine concave-convex structure has a center-line average roughness Ra of from 0.01 to 0.1 &mgr;m, ten or more convex portions with a height of from 0.5 to 1.0 &mgr;m, and two or less convex portions with a height larger than 1.0 &mgr;m on any 1 mm-long line segment, and the fine concave-convex structure has a surface hardness of from H to 4H in terms of pencil hardness.

Abstract: Disclosed are (1) a polarizer having a function of separating incident light into polarized light through reflection and transmission, which has (a) a haze of 10% or less, or (b) a ratio of parallel transmitted light to incident light of 40 to 60%, (c) a ratio of mirror reflected light to the incident light of 25% or more, (d) a ratio of diffusion reflected light to the incident light of 20% or less or (e) a fraction of mirror reflected light to the whole reflected light of 60% or more; (2) an optical element comprising the polarizer, and a 1/4 wavelength formed by one or two or more retardation layers disposed on at least one side thereof; (3) a lighting device comprising a surface light source, and the polarizer or the optical element disposed thereon; and (4) a liquid crystal display comprising the lighting device and a liquid crystal cell arranged on the light outgoing side thereof, with a polarizing plate intervening therebetween.

Abstract: A liquid crystal element which comprises an oriented liquid crystal polymer and with which a liquid crystal display less apt to have display unevenness in a wide viewing range including the front and slant directions can be fabricated; and an optical element and a polarizing element each containing the liquid crystal element. The liquid crystal element comprises either a layer of an oriented liquid crystal polymer or a substrate and formed thereon the layer of an oriented liquid crystal polymer, wherein the liquid crystal polymer layer has an average in-plane haze of 10% or higher and a dispersion of the in-plane haze H (%) within the range represented by the relationship a-.sqroot.(10a).ltoreq.H.ltoreq.a+.sqroot.(10a) wherein "a" is the average haze (%), or has an average in-plane haze lower than 10% and a dispersion of the in-plane haze H (%) within the range represented by the relationship 0.ltoreq.H.ltoreq.b+.sqroot.(10b) wherein "b" is the average haze (%).

Abstract: A circular dichroism optical element having the solidified layer of a liquid crystal polymer comprising a Grandjean oriented cholesteric liquid crystal phase, a liquid crystal display apparatus using the optical element, and a liquid crystal polymer composed of, as the component, a copolymer comprising at least two kinds of specific acrylic monomer units.

Abstract: A cholesteric liquid crystal layer which is inhibited from appearing to be colored when viewed from slant directions and thus has excellent viewing angle characteristics, while enabling an improvement in the brightness of liquid crystal displays, etc.; and an optical element and an lighting device with each of which liquid crystal displays and the like excellent in brightness and perceptibility can be fabricated. The cholesteric liquid crystal layer (1) has a helical pitch changing in the thickness direction and shows circular dichroism over a wavelength region having a width of at least 50 nm and including a wavelength of 550 nm, wherein the linearly polarized light obtained through a quarter-wavelength plate has a maximum degree of polarization at a wavelength not shorter than 550 nm, or the degree of polarization thereof in a wavelength region on the longer-wavelength side of 550 nm is higher than that in a wavelength region on the shorter-wavelength side of 550 nm.

Abstract: Disclosed are a method for producing a circularly polarized separated plate which comprises coating an oriented cholesteric liquid crystal polymer layer with a different kind of cholesteric liquid crystal polymer and heat orienting the resulting coated layer, or heat pressing oriented cholesteric liquid crystal polymer layers on each other, or adhering oriented cholesteric liquid crystal polymer layers to each other through a volatile liquid or a volatile liquid in which a cholesteric liquid crystal polymer is dissolved, thereby forming a close contact laminate of two or more cholesteric liquid crystal polymer layers in which an upper layer is different from a lower layer in helical pitch; a circularly polarized separated plate comprising a close contact laminate of two or more cholesteric liquid crystal polymer layers in which an upper layer is different from a lower layer in helical pitch, the laminate having a mixed layer of cholesteric liquid crystal polymers forming the upper and lower layers, which is d

Abstract: A liquid crystal element which comprises an oriented liquid crystal polymer and with which a liquid crystal display less apt to have display unevenness in a wide viewing range including the front and slant directions can be fabricated; and an optical element and a polarizing element each containing the liquid crystal element. The liquid crystal element comprises either a layer of an oriented liquid crystal polymer or a substrate and formed thereon the layer of an oriented liquid crystal polymer, wherein the liquid crystal polymer layer has an average in-plane haze of 10% or higher and a dispersion of the in-plane haze H (%) within the range represented by the relationship a-.sqroot.(10a).ltoreq.H.ltoreq.a+.sqroot.(10a) wherein "a" is the average haze (%), or has an average in-plane haze lower than 10% and a dispersion of the in-plane haze H (%) within the range represented by the relationship 0.ltoreq.H.ltoreq.b+.sqroot.(10b) wherein "b" is the average haze (%).

Abstract: Disclosed are (1) a polarizer having a function of separating incident light into polarized light through reflection and transmission, which has (a) a haze of 10% or less, or (b) a ratio of parallel transmitted light to incident light of 40 to 60%, (c) a ratio of mirror reflected light to the incident light of 25% or more, (d) a ratio of diffusion reflected light to the incident light of 20% or less or (e) a fraction of mirror reflected light to the whole reflected light of 60% or more; (2) an optical element comprising the polarizer, and a ¼ wavelength formed by one or two or more retardation layers disposed on at least one side thereof; (3) a lighting device comprising a surface light source, and the polarizer or the optical element disposed thereon; and (4) a liquid crystal display comprising the lighting device and a liquid crystal cell arranged on the light outgoing side thereof, with a polarizing plate intervening therebetween.