Abstract: The image forming optical system is capable of forming an image on a conjugated plane on a reduction side as an intermediate image and re-forming the intermediate image as a magnified image on a conjugated plane on a magnification side. The image forming optical system includes: a first adjustment group that moves along an optical axis in adjusting an image formation position of a region of the magnified image including a farthest point from the optical axis; and a second adjustment group that moves along the optical axis in adjusting an image formation position of a region of the magnified image including a nearest point from the optical axis. An optical element disposed closest to the magnification side is a lens. The second adjustment group has a positive refractive power as a whole, and is disposed closest to the reduction side.

Abstract: A projection-type display device includes: a display element including a rectangular displayable region in which an image is displayable; and a projection optical system. Assuming that a focal length of the projection optical system is f and a length of a long side of the displayable region is w, 0.15<|f|/w<0.45 is satisfied. An absorption layer that absorbs light is provided in at least a portion of a non-optically effective surface of a lens which is disposed closer to a reduction side than a first lens closest to an enlargement side in the projection optical system and at least a part of a portion which is irradiated with light that has been emitted from an image and reflected by an enlargement-side surface of the first lens or a reduction-side surface of the first lens.

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: An image forming optical system consists of a first optical system and a second optical system in order from a magnification side. An intermediate image is formed between the first optical system and the second optical system. Among the aspherical lenses included in the first optical system, a specific lens, which is the aspherical lens closest to the intermediate image on the optical path, has a meniscus shape of which a surface is convex toward the reduction side in a paraxial region. The image forming optical system satisfies a maximum image height, a focal length, and predetermined conditional expressions for the specific lens.

Abstract: An information processing apparatus acquires a plurality of lists including one or more rows from table data including a plurality of columns and a plurality of rows, based on a value of one column in the plurality of columns and extracts, based on a list including a predetermined search key among the acquired plurality of lists, a value corresponding to the search key. Thus, for example, even in a case where there is no character string on the right side of the search key, value information corresponding to the search key is extractable.

Abstract: An imaging lens consists of a front group and a rear group in order from the object side to the image side. The front group includes, as lenses, in order from the object side to the image side, only a positive meniscus lens having a surface convex toward the object side, a first cemented lens having a negative power as a whole, and a second cemented lens having a positive power as a whole. In the first cemented lens, a positive lens and a negative lens are cemented in order from the object side, with a surface convex toward the object side and a surface concave toward the image side. The rear group includes a negative most image side lens having a surface concave toward the object side at a position closest to the image side.

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: A projection-type display device includes: a display element including a rectangular displayable region in which an image is displayable; and a projection optical system. Assuming that a focal length of the projection optical system is f and a length of a long side of the displayable region is w, 0.15<|f|/w<0.45 is satisfied. An absorption layer that absorbs light is provided in at least a portion of a non-optically effective surface of a lens which is disposed closer to a reduction side than a first lens closest to an enlargement side in the projection optical system and at least a part of a portion which is irradiated with light that has been emitted from an image and reflected by an enlargement-side surface of the first lens or a reduction-side surface of the first lens.

Abstract: An image forming optical system consists of a first optical system and a second optical system in order from a magnification side. An intermediate image is formed between the first optical system and the second optical system. Among the aspherical lenses included in the first optical system, a specific lens, which is the aspherical lens closest to the intermediate image on the optical path, has a meniscus shape of which a surface is convex toward the reduction side in a paraxial region. The image forming optical system satisfies a maximum image height, a focal length, and predetermined conditional expressions for the specific lens.

Abstract: The imaging optical system forms a first intermediate image at a position conjugate to a magnification side imaging surface and a second intermediate image at a position closer to a reduction side than the first intermediate image on an optical path and conjugate to the first intermediate image. The imaging optical system consists of a first optical system, a second optical system, and a third optical system in order from the magnification side to the reduction side along the optical path. The imaging optical system does not include a reflective member having a power.

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: An imaging lens consists of a front group and a rear group in order from the object side to the image side. The front group includes, as lenses, in order from the object side to the image side, only a positive meniscus lens having a surface convex toward the object side, a first cemented lens having a negative power as a whole, and a second cemented lens having a positive power as a whole. In the first cemented lens, a positive lens and a negative lens are cemented in order from the object side, with a surface convex toward the object side and a surface concave toward the image side. The rear group includes a negative most image side lens having a surface concave toward the object side at a position closest to the image side.

Abstract: The imaging optical system forms a first intermediate image at a position conjugate to the magnification side imaging surface and a second intermediate image at a position closer to a reduction side than the first intermediate image on an optical path and conjugate to the first intermediate image. The imaging optical system consists of a first optical system, a second optical system, and a third optical system in order from a magnification side to the reduction side along the optical path. The imaging optical system is configured to be telecentric on the reduction side. The imaging optical system satisfies predetermined conditional expressions.

Abstract: The imaging optical system forms a first intermediate image at a position conjugate to the magnification side imaging surface and a second intermediate image at a position closer to a reduction side than the first intermediate image on an optical path and conjugate to the first intermediate image. The imaging optical system consists of a first optical system, a second optical system, and a third optical system in order from a magnification side to the reduction side along the optical path. The imaging optical system is configured to be telecentric on the reduction side. The imaging optical system satisfies predetermined conditional expressions.

Abstract: The imaging optical system forms a first intermediate image at a position conjugate to a magnification side imaging surface and a second intermediate image at a position closer to a reduction side than the first intermediate image on an optical path and conjugate to the first intermediate image. The imaging optical system consists of a first optical system, a second optical system, and a third optical system in order from the magnification side to the reduction side along the optical path. The imaging optical system does not include a reflective member having a power.

Abstract: The imaging optical system consists of, in order from a magnification side: a first optical system which makes a magnification side imaging surface and an intermediate image conjugate to each other; and a second optical system which makes the intermediate image and a reduction side imaging surface conjugate to each other. The imaging optical system is configured to be telecentric on the reduction side. The first optical system includes an aspheric lens. The second optical system consists of a front group and a rear group. The imaging optical system satisfies predetermined conditional expressions for a focal length of the front group, a focal length of the imaging optical system, a focal length of the rear group, a maximum image height, a focal length of the first optical system, and the aspheric lens of the first optical 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: 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: 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: 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).