Abstract: A zoom lens includes, in order from an object side in an optical axis a first lens group having a positive refractive power, a second lens group having a negative refractive power; a third lens group having a negative refractive power, a fourth lens group having a positive refractive power, a fifth lens group having a positive refractive power, and an aperture stop arranged between the third lens group and the fourth lens group, an interval between the first lens group and the second lens group being increased, an interval between the second lens group and the third lens group being varied, an interval between the third lens group and the fourth lens group being decreased, and an interval between the fourth lens group and the fifth lens group being decreased when changing a magnification from a wide-angle end to a telephoto end.

Abstract: A zoom lens includes first to fifth lens groups having positive, negative, negative, positive, and positive refractive powers, respectively, arranged along an optical axis in order from an object side, and an aperture stop disposed between the third and fourth lens groups. When zooming from wide angle end to telephoto end, the zoom lens is moved so that an interval between the first and second lens groups increases, an interval between the second and third lens groups varies, an interval between the third and fourth lens groups decreases, and the third lens group focuses. The second lens group is arranged to have a focal length to satisfy the following condition: 0.95<|f2/?(fw*ft)|<4.0 where f2 is a focal length of the second lens group, fw and ft are focal lengths of the entire zoom lens at wide angle end and at telephoto end, respectively.

Abstract: A zoom lens includes a first lens group having a positive refracting power, a second lens group having a negative refracting power, a third lens group having a positive refracting power, and a fourth lens group having a positive refracting power, being disposed in order from an object side, and an aperture stop disposed at an object side of the third lens group. When changing the magnification from a wide angle end to a telephoto end, an interval between the first and second lens groups increases, an interval between the second and third lens groups decreases, and an interval between the third and fourth lens groups changes.

Abstract: A zoom lens includes a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a fourth lens group having a positive refractive power, which are disposed in order from an object side, and an aperture stop disposed at an object side of the third lens group. When changing the magnification from a wide angle end to a telephoto end, an interval between the first and second lens groups increases, an interval between the second and third lens groups decreases, and an interval between the third and fourth lens groups increases. The first lens group includes a negative lens, a positive lens, and a positive lens, in order from the object side. Predetermined conditions of a refractive index of the negative lens E1 for a d line, an Abbe number for d line, and a relative partial dispersion are satisfied.

Abstract: A liquid crystal element comprising a pair of transparent substrates, a liquid crystal layer which fills in between the pair of substrates and can form a chiral smectic C phase in homeotropic orientation, and an electrode which generates, at least, an electric field (parallel electric field) in directions parallel to a principal face of the substrate for the liquid crystal layer is provided, wherein the liquid crystal layer comprises, at least, a chiral compound of the following general formula (1-I) or a chiral compound of the following general formula (2-I) and a chiral compound of the following general formula (2 -II) in a base liquid crystal material which can provide a phase sequence of an isotropic liquid phase, a nematic phase, a smectic A phase and a smectic C phase from a higher temperature side, wherein R1, A2, Z1, Z2, m and 1 in formula (1-I), X, R1, R2, and * in formula (2-I), and X, R3, R4, R5, and * in formula (2-II) are defined in the specification.

Abstract: A zoom lens includes a first lens group having a positive refracting power, a second lens group having a negative refracting power, a third lens group having a positive refracting power, and a fourth lens group having a positive refracting power, being disposed in order from an object side, and an aperture stop disposed at an object side of the third lens group. When changing the magnification from a wide angle end to a telephoto end, an interval between the first and second lens groups increases, an interval between the second and third lens groups decreases, and an interval between the third and fourth lens groups changes.

Abstract: A zoom lens includes a first lens group having a positive refracting power, a second lens group having a negative refracting power, a third lens group having a positive refracting power, and a fourth lens group having a positive refracting power, being disposed in order from an object side, and an aperture stop disposed at an object side of the third lens group. When changing the magnification from a wide angle end to a telephoto end, an interval between the first and second lens groups increases, an interval between the second and third lens groups decreases, and an interval between the third and fourth lens groups changes.

Abstract: A zoom lens unit, including in order from an object side to an image side: a first lens group having a positive refracting power; a second lens group having a negative refracting power; a third lens group having a positive refracting power; and a fourth lens group having a positive refracting power, an aperture stop being disposed on an object side of the third lens group, wherein the third lens group has at least two positive lenses and one negative lens, wherein all the positive lenses of the third lens group satisfy the following formula: (1) ?0.005865?d3p+0.93226<?gF3p<?0.005865?d3p+0.95226, where, ?d3p represents an Abbe number of each of the positive lenses of the third lens group, and ?gF3p represents a partial dispersion ratio of each of the positive lenses of the third lens group, defined by the formula: ?gF3p=(ng?nF)/(nF?nC).

Abstract: A disclosed electric field generating device includes an electric field generating unit including a substrate, line electrodes, and an electric field generating resistor and configured to generate an electric field. In the disclosed electric field generating device, the line electrodes are formed on at least one side of the substrate in parallel with each other so as to divide the side of the substrate into multiple sections; the electric field generating resistor is shaped like a strip and positioned so as to touch a part of each of the line electrodes; and some of the line electrodes have connectors for electric connection.

Abstract: A zoom lens includes a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a fourth lens group having a positive refractive power, which are disposed in order from an object side, and an aperture stop disposed at an object side of the third lens group. When changing the magnification from a wide angle end to a telephoto end, an interval between the first and second lens groups increases, an interval between the second and third lens groups decreases, and an interval between the third and fourth lens groups increases. The first lens group includes a negative lens, a positive lens, and a positive lens, in order from the object side. Predetermined conditions of a refractive index of the negative lens E1 for a d line, an Abbe number for d line, and a relative partial dispersion are satisfied.

Abstract: A zoom lens unit, including in order from an object side to an image side: a first lens group having a positive refracting power; a second lens group having a negative refracting power; a third lens group having a positive refracting power; and a fourth lens group having a positive refracting power, an aperture stop being disposed on an object side of the third lens group, wherein the third lens group has at least two positive lenses and one negative lens, wherein all the positive lenses of the third lens group satisfy the following formula: (1) ?0.005865?d3p+0.93226<?gF3p<?0.005865?d3p+0.95226, where, ?d3p represents an Abbe number of each of the positive lenses of the third lens group, and ?gF3p represents a partial dispersion ratio of each of the positive lenses of the third lens group, defined by the formula: ?gF3p=(ng?nF)/(nF?nC).

Abstract: A zoom lens includes a first lens group having a positive refracting power, a second lens group having a negative refracting power, a third lens group having a positive refracting power, and a fourth lens group having a positive refracting power, being disposed in order from an object side, and an aperture stop disposed at an object side of the third lens group. When changing the magnification from a wide angle end to a telephoto end, an interval between the first and second lens groups increases, an interval between the second and third lens groups decreases, and an interval between the third and fourth lens groups changes.

Abstract: A liquid crystal element comprising a pair of transparent substrates, a liquid crystal layer which fills in between the pair of substrates and can form a chiral smectic C phase in homeotropic orientation, and an electrode which generates, at least, an electric field (parallel electric field) in directions parallel to a principal face of the substrate for the liquid crystal layer is provided, wherein the liquid crystal layer comprises, at least, a chiral compound of the following general formula (1-I) or a chiral compound of the following general formula (2-I) and a chiral compound of the following general formula (2-II) in a base liquid crystal material which can provide a phase sequence of an isotropic liquid phase, a nematic phase, a smectic A phase and a smectic C phase from a higher temperature side, wherein R1, A2, Z1, Z2, m and I in formula (1-I), X, R1, R2, and * in formula (2-I), and X, R3, R4, R5, and * in formula (2-II) are defined in the specification.

Abstract: A disclosed electric field generating device includes an electric field generating unit including a substrate, line electrodes, and an electric field generating resistor and configured to generate an electric field. In the disclosed electric field generating device, the line electrodes are formed on at least one side of the substrate in parallel with each other so as to divide the side of the substrate into multiple sections; the electric field generating resistor is shaped like a strip and positioned so as to touch a part of each of the line electrodes; and some of the line electrodes have connectors for electric connection.