Abstract: A zoom lens forms an intermediate image at a position conjugate to a reduction side imaging plane and forms the intermediate image again on a magnification side imaging plane. The zoom lens includes a plurality of lens groups including at least two movable lens groups, which move by changing spacings between the groups adjacent to each other in a direction of an optical axis during zooming, at a position closer to the reduction side than the intermediate image. Among the plurality of lens groups, a final lens group closest to the reduction side has a positive refractive power, and remains stationary with respect to the reduction side imaging plane during zooming. The zoom lens satisfies predetermined conditional expressions (1) and (2) about the focal lengths of the movable lens groups.

Abstract: The imaging optical system consists of first and second optical systems in order from a magnified side. The second optical system forms an image on an image display surface as an intermediate image. The first optical system forms the intermediate image on a magnified-side conjugate plane. A height H of a principal ray of light having a maximum angle of view becomes maximum on a lens surface of the whole system (having focal length f) on the most magnified side, among heights of principal rays of light having a maximum angle of view on respective lens surfaces, satisfying predetermined Conditional Expressions (1) and (2): 0.03<H×|f|/(L×I)<0.09??(1) 0.35<I/dl??(2) Where L is an optical axis distance between lens surfaces on the most magnified and reduced sides, I is a reduced side maximum image height, and dl is a maximum air spacing on the optical axis within the system.

Abstract: A zoom lens forms an intermediate image at a position conjugate to a reduction side imaging plane and forms the intermediate image again on a magnification side imaging plane. The zoom lens includes a plurality of lens groups including at least two movable lens groups, which move by changing spacings between the groups adjacent to each other in a direction of an optical axis during zooming, at a position closer to the reduction side than the intermediate image. Among the plurality of lens groups, a final lens group closest to the reduction side has a positive refractive power, and remains stationary with respect to the reduction side imaging plane during zooming. The zoom lens satisfies predetermined conditional expressions (1) and (2) about the focal lengths of the movable lens groups.

Abstract: The imaging optical system consists of a first optical system and a second optical system in order from a magnified side. The first optical system consists of a la lens group, first optical path bender, and a 1b lens group in order from the magnified side, and the second optical system consists of a 2a lens group, second optical path bender, and a 2b lens group in order from the magnified side. The second optical system forms an image on an image display surface as an intermediate image, and the first optical system forms the intermediate image on a magnified-side conjugate plane, to satisfy the following predetermined Conditional Expression (1), 3<d/I??(1).

Abstract: The imaging optical system consists of first and second optical systems in order from a magnified side. The second optical system forms an image on an image display surface as an intermediate image. The first optical system forms the intermediate image on a magnified-side conjugate plane. A height H of a principal ray of light having a maximum angle of view becomes maximum on a lens surface of the whole system (having focal length f) on the most magnified side, among heights of principal rays of light having a maximum angle of view on respective lens surfaces, satisfying predetermined Conditional Expressions (1) and (2): 0.03<H×|f|/(L×I)<0.09??(1) 0.35<I/dl??(2) Where L is an optical axis distance between lens surfaces on the most magnified and reduced sides, I is a reduced side maximum image height, and dl is a maximum air spacing on the optical axis within the system.

Abstract: The imaging optical system consists of, in order from a magnification side along an optical axis: a first lens group; a first optical axis deflection unit that deflects the optical axis; a second lens group; a second optical axis deflection unit that deflects the optical axis; and a third lens group. The imaging optical system forms an intermediate image between the first optical axis deflection unit and a surface closest to the magnification side in the first lens group.

Abstract: An imaging optical system consists of, in order from a magnification side: a first optical system that forms an intermediate image on a position conjugate to a magnification side imaging surface; and a second optical system that re-forms the intermediate image on a reduction side imaging surface. The first optical system includes at least two focusing lens groups that move with different loci during focusing. The imaging optical system satisfies predetermined conditional expressions relating to the focusing lens groups.

Abstract: A zoom lens forms an intermediate image at a position conjugate to a reduction side imaging plane and forms the intermediate image again on a magnification side imaging plane. The zoom lens includes a first optical system on the magnification side, and a second optical system on the reduction side. The intermediate image is formed between the magnification and reduction sides. The second optical system includes two or more movable lens groups, which move by changing spacings between the groups adjacent to each other in a direction of an optical axis during zooming, and two stationary lens groups which remain stationary with respect to the reduction side imaging plane during zooming. One stationary lens group is disposed closest to the reduction side, and has a positive refractive power. Also, a lens group closest to the magnification side in the second optical system has a positive refractive power.

Abstract: The zoom lens forms an intermediate image at a position conjugate to a reduction side imaging plane and forms the intermediate image again on a magnification side imaging plane. The zoom lens includes: a first optical system on the magnification side; and a second optical system on the reduction side. The intermediate image is formed between the magnification and reduction sides. The second optical system includes two or more movable lens groups, which move by changing spacings between the groups adjacent to each other in a direction of an optical axis during zooming, and one or more stationary lens groups which remain stationary with respect to the reduction side imaging plane during zooming. Also, the movable lens groups are disposed to be adjacent to both the magnification side and the reduction side of the stationary lens group closest to the magnification side in the second optical system.

Abstract: The wide-angle lens consists of a projection lens which is disposed closer to a magnified side than an intermediate image, and a relay lens which is disposed closer to a reduced side than the intermediate image and is configured to be attachable and detachable to and from the projection lens, and satisfies the following Conditional Expressions (1) and (2). 0<|FC/FC2|<0.2??(1) 0.

Abstract: A zoom lens forms an intermediate image at a position conjugate to a reduction side imaging plane and forms the intermediate image again on a magnification side imaging plane. The zoom lens includes a plurality of lens groups including at least two movable lens groups, which move by changing spacings between the groups adjacent to each other in a direction of an optical axis during zooming, at a position closer to the reduction side than the intermediate image. Among the plurality of lens groups, a final lens group closest to the reduction side has a positive refractive power, and remains stationary with respect to the reduction side imaging plane during zooming. The zoom lens satisfies predetermined conditional expressions (1) and (2).

Abstract: The imaging optical system consists of, in order from a magnification side: a first imaging optical system that forms an intermediate image on a position conjugate to a magnification side imaging surface; and a second imaging optical system that re-forms the intermediate image on a reduction side imaging surface. The first imaging optical system consists of, in order from the magnification side, a first A lens group, a first optical path deflection unit that deflects an optical path, a first B lens group, and a second optical path deflection unit that deflects the optical path. In addition, the intermediate image is formed between the second optical path deflection unit and the second imaging optical system.

Abstract: In the zoom lens, a first optical system is formed on the magnification side, and a second optical system is formed on the reduction side, with the intermediate image formed between the first optical system and the second optical system. The second optical system consists of, in order from the magnification side, a first lens group that has a positive power, a second lens group that has a positive power, a third lens group that has a positive or negative power, and a fourth lens group that has a positive power. During zooming, the second lens group and the third lens group are moved by changing spacings between the groups adjacent to each other in a direction of an optical axis, and the fourth lens group remains stationary with respect to the reduction side imaging plane.

Abstract: The imaging optical system consists of, in order from the magnification side, a first optical system forming an intermediate image and a second optical system re-forming the intermediate image, and is configured to be telecentric on the reduction side. The imaging optical system satisfies predetermined conditional expressions relating to a ray height on a lens surface closest to the magnification side in the second optical system, a ray height on a lens surface closest to the reduction side in the first optical system, and heights of rays at a position where a principal ray with the maximum angle of view intersects with the optical axis in the second optical system.

Abstract: The imaging lens includes at least one negative lens that satisfies predetermined Conditional Expressions (1) to (3) indicating conditions in which dispersion is relatively low and refractive index is high while having a negative rate of change of the refractive index. A positive lens having a largest Abbe number at the d line among positive lenses included in the imaging lens satisfies predetermined Conditional Expressions (4) and (5).

Abstract: Provided are a zoom lens, a projection display device including the zoom lens, and an imaging apparatus including the zoom lens. The zoom lens forms an intermediate image at a position conjugate to a reduction side imaging plane and forms the intermediate image again on a magnification side imaging plane. The zoom lens includes: a first optical system on the magnification side; and a second optical system on the reduction side. The intermediate image is formed between the magnification side and the reduction side. The second optical system includes two movable lens groups, which move by changing spacings between the groups adjacent to each other in a direction of an optical axis during zooming, and two stationary lens groups which remain stationary with respect to the reduction side imaging plane during zooming. One stationary lens group is disposed to be closest to the reduction side, and has a positive refractive power.

Abstract: The wide-angle lens forms an intermediate image at a position conjugate to a reduction side imaging plane and forms the intermediate image again on a magnification side imaging plane. The wide-angle lens includes: a first optical system on the magnification side; and a second optical system on the reduction side. The intermediate image is formed between the magnification side and the reduction side. The first optical system has an optical axis deflection prism which satisfies predetermined conditional expressions.

Abstract: A projection zoom lens is configured to have an intermediate group that essentially consists of two or three moving lens groups positioned between a first lens group and a final lens group, both of which have positive refractive powers and are fixed while changing magnification. The projection zoom lens changes magnification by moving these moving lens groups. Further, the projection zoom lens satisfies conditional formulas (1) and (2) below: d/fw<1.0??(1), 1.5<fe/fw<7.0??(2), where, d: the distance between the most-reduction-side lens surface of the intermediate group and the most-reduction-side lens surface of the final lens group along the optical axis at the wide angle end, fw: the focal length of the entire system at the wide angle end, and fe: the focal length of the final lens group.

Abstract: A zoom lens forms an intermediate image at a position conjugate to a reduction side imaging plane and forms the intermediate image again on a magnification side imaging plane. The zoom lens includes a plurality of lens groups including at least two movable lens groups, which move by changing spacings between the groups adjacent to each other in a direction of an optical axis during zooming, at a position closer to the reduction side than the intermediate image. Among the plurality of lens groups, a final lens group closest to the reduction side has a positive refractive power, and remains stationary with respect to the reduction side imaging plane during zooming. The zoom lens satisfies predetermined conditional expressions (1) and (2) about the focal lengths of the movable lens groups.

Abstract: Provided are a zoom lens that has a small size with a wide angle and has a simple configuration, a projection display device including the zoom lens, and an imaging apparatus including the zoom lens. The zoom lens forms an intermediate image at a position conjugate to a reduction side imaging plane and forms the intermediate image again on a magnification side imaging plane. The zoom lens includes: a first optical system on the magnification side; and a second optical system on the reduction side. The intermediate image is formed between the magnification side and the reduction side. The second optical system includes two movable lens groups, which move by changing spacings between the groups adjacent to each other in a direction of an optical axis during zooming, and two stationary lens groups which remain stationary with respect to the reduction side imaging plane during zooming.