Abstract: A magnification optical system forms an enlarged image of an object. It includes a refractive optical system including a plurality of lens groups; and a mirror train including a curved mirror, arranged in this order from an object side, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of a conjugate surface on the object side, and a second focus structure configured to move the respective lens groups along the normal line of the conjugate surface on the object side by different amounts from those of the first focus structure.

Abstract: An image display device includes an image display element, a light source, an illumination system, a projector system comprising a refractive optical system including a plurality of lens groups, and a mirror train including a curved mirror, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of the image display element, and a second focus structure configured to move the respective lens groups along the normal line of the image display element by different amounts from those of the first focus structure.

Abstract: An image display device includes an image display element, a light source, an illumination system, a projector system comprising a refractive optical system including a plurality of lens groups, and a mirror train including a curved mirror, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of the image display element, and a second focus structure configured to move the respective lens groups along the normal line of the image display element by different amounts from those of the first focus structure.

Abstract: A magnification optical system forms an enlarged image of an object. It includes a refractive optical system including a plurality of lens groups; and a mirror train including a curved mirror, arranged in this order from an object side, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of a conjugate surface on the object side, and a second focus structure configured to move the respective lens groups along the normal line of the conjugate surface on the object side by different amounts from those of the first focus structure.

Abstract: A magnification optical system forms an enlarged image of an object. It includes a refractive optical system including a plurality of lens groups; and a mirror train including a curved mirror, arranged in this order from an object side, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of a conjugate surface on the object side, and a second focus structure configured to move the respective lens groups along the normal line of the conjugate surface on the object side by different amounts from those of the first focus structure.

Abstract: A magnification optical system forms an enlarged image of an object. It includes a refractive optical system including a plurality of lens groups; and a mirror train including a curved mirror, arranged in this order from an object side, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of a conjugate surface on the object side, and a second focus structure configured to move the respective lens groups along the normal line of the conjugate surface on the object side by different amounts from those of the first focus structure.

Abstract: A magnification optical system forms an enlarged image of an object. It includes a refractive optical system including a plurality of lens groups; and a mirror train including a curved mirror, arranged in this order from an object side, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of a conjugate surface on the object side, and a second focus structure configured to move the respective lens groups along the normal line of the conjugate surface on the object side by different amounts from those of the first focus structure.

Abstract: A magnification optical system forms an enlarged image of an object. It includes a refractive optical system including a plurality of lens groups; and a mirror train including a curved mirror, arranged in this order from an object side, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of a conjugate surface on the object side, and a second focus structure configured to move the respective lens groups along the normal line of the conjugate surface on the object side by different amounts from those of the first focus structure.

Abstract: A magnification optical system forms an enlarged image of an object. It includes a refractive optical system including a plurality of lens groups; and a mirror train including a curved mirror, arranged in this order from an object side, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of a conjugate surface on the object side, and a second focus structure configured to move the respective lens groups along the normal line of the conjugate surface on the object side by different amounts from those of the first focus structure.

Abstract: A magnification optical system forms an enlarged image of an object. It includes a refractive optical system including a plurality of lens groups; and a mirror train including a curved mirror, arranged in this order from an object side, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of a conjugate surface on the object side, and a second focus structure configured to move the respective lens groups along the normal line of the conjugate surface on the object side by different amounts from those of the first focus structure.

Abstract: Disclosed is an enlargement optical system configured to form an image of an object at an enlargement side, including a lens system and a mirror system in order from a side of the object, the lens system including at least one lens, the mirror system including a first mirror and a second mirror in order from a side of the object, and the second mirror being an concave mirror, wherein an intermediate image conjugate to the object is formed at a side of the object with respect to the second mirror and the first mirror is held to be capable of adjusting a position thereof.

Abstract: A magnification optical system forms an enlarged image of an object. It includes a refractive optical system including a plurality of lens groups; and a mirror train including a curved mirror, arranged in this order from an object side, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of a conjugate surface on the object side, and a second focus structure configured to move the respective lens groups along the normal line of the conjugate surface on the object side by different amounts from those of the first focus structure.

Abstract: Disclosed is an image displaying apparatus including an image displaying element configured to form an image to be projected and a projection optical system having a positive refractive power and configured to project the image to be projected onto a screen, wherein the projection optical system includes a lens optical system and a mirror optical system, the lens optical system including plural lens groups, the mirror optical system including a first mirror and a second mirror, the second mirror being a concave mirror, wherein an intermediate image of a pixel of the image displaying element is formed between the image displaying element and the second mirror, and wherein the first mirror is held to be capable of adjusting a position thereof.

Abstract: A magnification optical system forms an enlarged image of an object. It includes a refractive optical system including a plurality of lens groups; and a mirror train including a curved mirror, arranged in this order from an object side, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of a conjugate surface on the object side, and a second focus structure configured to move the respective lens groups along the normal line of the conjugate surface on the object side by different amounts from those of the first focus structure.

Abstract: An image displaying apparatus including a light source, an image displaying element configured to control exiting of incident light to display an image, an illumination optical system configured to illuminate the image displaying element with light exiting from the light source, and a projection optical system configured to project an image displayed on a display surface of the image displaying element, to provide an enlarged display. The projection optical system includes a lens optical system, a first mirror configured to reflect light transmitted through the lens optical system, and a second mirror configured to reflect light reflected from the first mirror toward the surface to be projected onto, and one of the mirrors is arranged at a position conjugate to the image displaying element, and wherein an optical surface of the one mirror is arranged to face vertically downward.

Abstract: A magnification optical system forms an enlarged image of an object. It includes a refractive optical system including a plurality of lens groups; and a mirror train including a curved mirror, arranged in this order from an object side, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of a conjugate surface on the object side, and a second focus structure configured to move the respective lens groups along the normal line of the conjugate surface on the object side by different amounts from those of the first focus structure.

Abstract: A magnification optical system forms an enlarged image of an object. It includes a refractive optical system including a plurality of lens groups; and a mirror train including a curved mirror, arranged in this order from an object side, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of a conjugate surface on the object side, and a second focus structure configured to move the respective lens groups along the normal line of the conjugate surface on the object side by different amounts from those of the first focus structure.

Abstract: An image-forming lens includes, in order from an object side to an image side, a first group having a negative power as a whole, the first group consisting of a positive meniscus lens having a convex surface on the object side and a negative meniscus lens having a convex surface on the object side, the positive meniscus lens and the negative meniscus lens being cemented, an aperture stop, a second group consisting of a positive meniscus lens having a convex surface on the image side, a third group consisting of a positive meniscus lens having a convex surface on the image side, a fourth group consisting of a lens having a negative power, and a fifth group consisting of a biconcave lens.

Abstract: A magnification optical system forms an enlarged image of an object. It includes a refractive optical system including a plurality of lens groups; and a mirror train including a curved mirror, arranged in this order from an object side, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of a conjugate surface on the object side, and a second focus structure configured to move the respective lens groups along the normal line of the conjugate surface on the object side by different amounts from those of the first focus structure.

Abstract: Disclosed is an enlargement optical system configured to form an image of an object at an enlargement side, including a lens system and a mirror system in order from a side of the object, the lens system including at least one lens, the mirror system including a first mirror and a second mirror in order from a side of the object, and the second mirror being an concave mirror, wherein an intermediate image conjugate to the object is formed at a side of the object with respect to the second mirror and the first mirror is held to be capable of adjusting a position thereof.