Abstract: An optical element includes a three-dimensional structure having a curved surface; and a retardation plate bent along the curved surface. The retardation plate includes a transparent substrate and a liquid crystal layer formed over the transparent substrate. The retardation plate has a slow axis and a fast axis. A glass-transition temperature, Tgne, in a slow axis direction of the retardation plate is higher than a glass-transition temperature, Tgno, in a fast axis direction of the retardation plate.

Abstract: A retardation plate includes a transparent substrate, and a liquid crystal layer formed over the transparent substrate, wherein, when a tensile test is performed by pulling the retardation plate in a predetermined direction at a glass-transition temperature of the transparent substrate, a tensile elongation C defined by an equation of C=(B?A)/A×100 is 12% or more, where A is an initial size of the retardation plate in the predetermined direction, and B is a size of the retardation plate in the predetermined direction when a crack penetrating the liquid crystal layer in a thickness direction occurs over a length of 1 mm or more on a surface of the liquid crystal layer.

Abstract: An optical element includes a three-dimensional structure having a curved surface; and a retardation plate bent along the curved surface. The retardation plate includes a transparent substrate and a liquid crystal layer formed over the transparent substrate. The retardation plate has a slow axis and a fast axis. A glass-transition temperature, Tgne, in a slow axis direction of the retardation plate is higher than a glass-transition temperature, Tgno, in a fast axis direction of the retardation plate.

Abstract: An optical element includes a transparent substrate; an alignment layer formed over the transparent substrate; and a liquid crystal layer formed over the alignment layer. A plurality of grooves parallel to each other for aligning liquid crystal molecules of the liquid crystal layer are formed over a surface of the alignment layer in contact with the liquid crystal layer. A pitch of the grooves is greater than or equal to 10 nm and less than or equal to 600 nm. The alignment layer is formed of a copolymer of an energy curable composition and contains fluorine on the surface.

Abstract: An optical device has a visible light transmittance that decreases from a central part thereof towards a peripheral part thereof. The optical device includes a visible light absorbing part, made of a material that absorbs at least a part of visible light, and having a thickness that increases from a central part thereof towards a peripheral part thereof, and a visible light transmitting part, made of a material that transmits the visible light, and is stacked on the visible light absorbing part. A relationship T420/T360>=3 is satisfied, where T420 denotes a transmittance of light having a wavelength of 420 nm, and T360 denotes a transmittance of light having a wavelength of 360 nm.

Abstract: An optical device has a visible light transmittance that decreases from a central part thereof towards a peripheral part thereof. The optical device includes a visible light absorbing part, made of a material that absorbs at least a part of visible light, and having a thickness that increases from a central part thereof towards a peripheral part thereof, and a visible light transmitting part, made of a material that transmits the visible light, and is stacked on the visible light absorbing part. A relationship T420/T360>=3 is satisfied, where T420 denotes a transmittance of light having a wavelength of 420 nm, and T360 denotes a transmittance of light having a wavelength of 360 nm.

Abstract: The present invention provides an optical anisotropic material having a good light stability, and provides a di(meth)acrylate compound represented by the following formula (1) and a polymerizable liquid crystalline composition that are suitable for the production of the optical anisotropic material. Further, the present invention provides an optical element having a good light stability and an optical information writing/reading device using the same.

Abstract: The present invention provides an optical anisotropic material having a good light stability, and provides a di(meth)acrylate compound represented by the following formula (1) and a polymerizable liquid crystalline composition that are suitable for the production of the optical anisotropic material. Further, the present invention provides an optical element having a good light stability and an optical information writing/reading device using the same.

Abstract: To provide a liquid crystal optical modulation element which is excellent in durability against blue laser and which can maintain the characteristics for a long period of time. A liquid crystal optical modulation element to modulate a laser beam having a wavelength of at most 500 nm, which comprises a layer of a polymer liquid crystal composition sandwiched between a pair of transparent substrates facing each other, characterized in that each of the pair of transparent substrates has an alignment film on the surface which faces the other transparent substrate, and the polymer liquid crystal composition is a polymer liquid crystal containing a hindered amine compound and a hindered phenol compound.

Abstract: A bifunctional polymerizable compound represented by the following formula: A-E1-E2-(E3)k-E4-B wherein A is CH2?CR1—COO-(L1)m-; B is CH2?CR2—COO-(L2)n-; each of R1 and R2 which are independent of each other, is a hydrogen atom or a methyl group; each of L1 and L2 is —(CH2)P— wherein p is each independently an integer of from 2 to 8, each of m and n which are independent of each other, is 0 or 1, provided that when at least one of m and n is 1, there may be an etheric oxygen atom between the carbon-carbon linkage of —(CH2)P— or at the terminal on the side bonded to E1 or E4, and at least one hydrogen atom may be substituted by a fluorine atom, a chlorine atom or a methyl group; each of E1 and E4 is a 1,4-phenylene group; and one of E2 and E3 is a trans-1,4-cyclohexylene group and the other is a trans-1,4-cyclohexylene group or a 1,4-phenylene group, k is 0 or 1, provided that when k is 0, E2 is a trans-1,4-cyclohexylene group, and the 1,4-phenylene group and the trans-1,4-cyclohexylene group as E1 to E4 m

Abstract: To provide a liquid crystal optical modulation element which is excellent in durability against blue laser and which can maintain the characteristics for a long period of time. A liquid crystal optical modulation element to modulate a laser beam having a wavelength of at most 500 nm, which comprises a layer of a polymer liquid crystal composition sandwiched between a pair of transparent substrates facing each other, characterized in that each of the pair of transparent substrates has an alignment film on the surface which faces the other transparent substrate, and the polymer liquid crystal composition is a polymer liquid crystal containing a hindered amine compound and a hindered phenol compound.

Abstract: To provide a liquid crystal optical modulation element which is excellent in durability against blue laser and which can maintain the characteristics for a long period of time. A liquid crystal optical modulation element to modulate a laser beam having a wavelength of at most 500 nm, which comprises a layer of a polymer liquid crystal composition sandwiched between a pair of transparent substrates facing each other, characterized in that each of the pair of transparent substrates has an alignment film on the surface which faces the other transparent substrate, and the polymer liquid crystal composition is a polymer liquid crystal containing a hindered amine compound and a hindered phenol compound.

Abstract: To provide a liquid crystal optical modulation element which is excellent in durability against blue laser and which can maintain the characteristics for a long period of time. A liquid crystal optical modulation element to modulate a laser beam having a wavelength of at most 500 nm, which comprises a layer of a polymer liquid crystal composition sandwiched between a pair of transparent substrates facing each other, characterized in that each of the pair of transparent substrates has an alignment film on the surface which faces the other transparent substrate, and the polymer liquid crystal composition is a polymer liquid crystal containing a hindered amine compound and a hindered phenol compound.

Abstract: To provide a liquid crystal optical modulation element which is excellent in durability against blue laser and which can maintain the characteristics for a long period of time. A liquid crystal optical modulation element to modulate a laser beam having a wavelength of at most 500 nm, which comprises a layer of a polymer liquid crystal composition sandwiched between a pair of transparent substrates facing each other, characterized in that each of the pair of transparent substrates has an alignment film on the surface which faces the other transparent substrate, and the polymer liquid crystal composition is a polymer liquid crystal containing a hindered amine compound and a hindered phenol compound.

Abstract: A bifunctional polymerizable compound represented by the following formula: A-E1-E2-(E3)k-E4-B wherein A is CH2?CR1—COO-(L1)m-; B is CH2?CR2—COO-(L2)n-; each of R1 and R2 which are independent of each other, is a hydrogen atom or a methyl group; each of L1 and L2 is —(CH2)p— wherein p is each independently an integer of from 2 to 8, each of m and n which are independent of each other, is 0 or 1, provided that when at least one of m and n is 1, there may be an etheric oxygen atom between the carbon-carbon linkage of —(CH2)p— or at the terminal on the side bonded to E1 or E4, and at least one hydrogen atom may be substituted by a fluorine atom, a chlorine atom or a methyl group; each of E1 and E4 is a 1,4-phenylene group; and one of E2 and E3 is a trans-1,4-cyclohexylene group and the other is a trans-1,4-cyclohexylene group or a 1,4-phenylene group, k is 0 or 1, provided that when k is 0, E2 is a trans-1,4-cyclohexylene group, and the 1,4-phenylene group and the trans-1,4-cyclohexylene group as E

Abstract: A liquid crystal compound represented by the formula CH2?CR1—COO-(L)k-E1-E2-E3-E4-R2 wherein R1: a hydrogen atom or a methyl group; R2: a C1-8 alkyl group; k: 0 or 1; L: —(CH2)pO— or —(CH2)q— (wherein each of p and q which are independent of each other, is an integer of from 2 to 8); E1: a 1,4-phenylene group; E2, E3, E4: each independently a 1,4-phenylene group or a trans-1,4-cyclohexylene group and at least one of E2 and E3 is a trans-1,4-cyclohexylene group, provided that the 1,4-phenylene group and trans-1,4-cyclohexylene group in E1 to E4, may be such that a hydrogen atom bonded to a carbon atom in each group may be substituted by a fluorine atom, a chlorine atom or a methyl group. To provide a novel liquid crystal compound for preparing an optical element which can exhibit a proper Rd value depending upon usable wavelength and application and which is excellent in durability against a blue laser beam.

Abstract: The present compound represented by formula(I) CH2?CR1—COO—(L)k-E1-E2-E3-(E4)m-(E5)n-R2??(1) provided that the symbols in the formula have the following meanings: R1: a hydrogen atom or a methyl group; R2: a C1-8 alkyl group; L: —(CH2)pO—, —(CH2)q—, -Cy-COO— (Cy is a trans-1,4-cyclohexylene group), -Cy-OCO—, -E6-(CH2)2—, -E7-CH2O— or -E8-O— (wherein each of p and q which are independent of each other, is an integer of from 2 to 8); E1, E2, E3 E4, E5, E6, E7, E8: each independently a 1,4-pheneylene group or a trans-1,4-cyclohexylene group (provided that at least one of E1, E2 and E3 is a trans-1,4-cyclohexylene group, and in a case where L is -Cy-OCO—, E1 is a trans-1,4-cyclohexylene group),and k, m, n: each independently 0 or 1, provided that when k is 1 and L is -Cy-COO—, -Cy-OCO—, -E6-(CH2)2—, -E7-CH2O— or -E8-O—, at least one of m and n is 0. The present compound is useful for liquid crystal composition and optical element.

Abstract: To provide a liquid crystal optical modulation element which is excellent in durability against blue laser and which can maintain the characteristics for a long period of time. A liquid crystal optical modulation element to modulate a laser beam having a wavelength of at most 500 nm, which comprises a layer of a polymer liquid crystal composition sandwiched between a pair of transparent substrates facing each other, characterized in that each of the pair of transparent substrates has an alignment film on the surface which faces the other transparent substrate, and the polymer liquid crystal composition is a polymer liquid crystal containing a hindered amine compound and a hindered phenol compound.

Abstract: To provide a novel liquid crystal compound for preparing, for example, an optical element which can exhibit a proper Rd value depending upon usable wavelength and application and which is excellent in durability against a blue laser beam. A liquid crystal compound represented by the formula CH2?CR1—COO-(L)k-E1-E2-E3-E4-R2 wherein R1: a hydrogen atom or a methyl group; R2: a C1-8 alkyl group; k:0 or 1; L: —(CH2)pO— or —(CH2)q— (wherein each of p and q which are independent of each other, is an integer of from 2 to 8); E1: a 1,4-phenylene group; E2, E3, E4: each independently a 1,4-pheneylene group or a trans-1,4-cyclohexylene group and at least one of E2 and E3 is a trans-1,4-cyclohexylene group, provided that the 1,4-phenylene group and trans-1,4-cyclohexylene group in E1 to E4, may be such that a hydrogen atom bonded to a carbon atom in each group may be substituted by a fluorine atom, a chlorine atom or a methyl group.

Abstract: To provide a novel compound which satisfies characteristics required for an optical anisotropic material and which is excellent in durability against blue laser light, a liquid crystal composition containing the compound and an optical anisotropic material employing the liquid crystal composition. A compound represented by the following formula (1): CH2?CR1—COO-(E1)m-Cy-Y-Cy-E2-R2??(1) provided that the symbols in the formula have the following meanings. R1: a hydrogen atom or a methyl group; R2: a C1-8 alkyl group; Y: —OCO— or —COO—; m: 0 or 1; E1 and E2: each independently a 1,4-phenylene group or a trans-1,4-cyclohexylene group; and Cy: a trans-1,4-cyclohexylene group; provided that the above 1,4-phenylene group and the trans-1,4-cyclohexylene group may be such that a hydrogen atom in each group may be substituted by a fluorine atom, a chlorine atom or a methyl group.