Abstract: A zoom lens system includes plural optical units each of which includes plural optical elements each having a rotationally asymmetrical surface, and changes optical power as the optical elements in each of the plural optical units move in directions different from an optical axis, wherein a principal point position moves in an optical-axis direction without causing the optical element to move in the optical-axis direction, the zoom lens system having such a shape that the principal point position of at least one unit of the plural optical units is located outside the one unit.

Abstract: A zoom lens system includes plural optical units each of which includes plural optical elements each having a rotationally asymmetrical surface, and changes optical power as the optical elements in each of the plural optical units move in directions different from an optical axis, wherein the plural optical units have first and second units, and when the optical power of the first unit changes from positive to negative, the second unit changes from negative to positive, wherein a variation range of the optical power of an entire system includes a point where the first and second units have the same optical power, and wherein the point shifts to a side where optical power is greater than a center of the variation range of the optical power of the entire system.

Abstract: The optical system disclosed in this specification is a variable power optical system for enlarging and projecting a reduction side object onto an enlargement side image plane, or reducing and projecting an enlargement side object onto a reduction side image plane. This variable power optical system includes a first optical component having a reflecting curved surface, and a second optical component disposed more toward the reduction side than the first optical component. The second optical component has a plurality of movable lens units, and the variable power optical system effects a variable power operation by movement of the plurality of lens units. If ray was traced from the reduction side toward the enlargement side, the second optical component forms an image of a reduction side conjugate point on the enlargement side than an optical surface of the first optical component that is most adjacent to the reduction side.

Abstract: A six-mirror catoptric projection optical system for projecting a reduced size of a pattern on an object onto an image plane includes first, second, third, fourth, fifth, and sixth mirrors from the image plane along an optical path, wherein the third and fourth mirrors are located between the fifth mirror and sixth mirror and wherein the catoptric projection optical system forms an intermediate image along the optical path from the third mirror to the fifth mirror.

Abstract: A catoptric projection optical system for projecting a reduced size of a pattern on an object surface onto an image surface and for serving as an imaging system that forms an intermediate image between the object surface and image surface, includes six or more mirrors, wherein a position of an exit pupil with respect to the intermediate image is located between the object surface and image surface, and wherein the largest angle between principal rays and an optical axis for angles of view at the position of the exit pupil is sin?1NA or smaller, where NA is a numerical aperture at the side of the image surface.

Abstract: There is disclosed a projection optical system which is capable of moving a projected image within a predetermined region (effective projection region). The projection optical system, which projects an image of an object surface in the effective projection region of a predetermined image surface comprises two or more optical systems, among which a first optical system on the object surface side comprises a zoom portion which zooms the projected image. The projection optical system further comprises one or more rotatable members which rotate around the position of an exit pupil of the first optical system or its vicinity. In addition, by rotating the one or more rotatable members, the projected image is moved within the effective projection region.

Abstract: An image-formation optical system is disclosed which is an off-axial optical system configured using reflective surfaces, with which the performance deterioration with respect to manufacturing discrepancies is reduced, and which can be made sufficiently compact. The image-formation optical system comprises a reflective optical unit including a plurality of reflective surfaces. Each of the reflective surfaces has a curvature and a rotationally asymmetric shape. Moreover, L/{Er(S−1)} is smaller than 2.2 and L/{Eo (S−1)} is larger than 3.

Abstract: A compact image-forming optical system is disclosed which has a high optical performance due to arranging a reflective optical unit and a refractive optical unit at suitable positions. The image-forming optical system is an optical system performing image formation from a magnifying side to a demagnifying side or from the demagnifying side to the magnifying side, and includes, in order from the magnifying side to the demagnifying side, a refractive optical unit having a positive optical power as a whole, and a reflective optical unit including at least three reflective surfaces. The image-forming optical system has a pupil on the magnifying side further from the reflective surface furthest on the magnifying side the reflective optical unit, and the focal length of the refractive optical unit is set to be within a range of 0.2 to 5 times the focal length of the reflective optical unit.

Abstract: A catoptric projection optical system for projecting a reduced size of a pattern on an object surface onto an image surface includes six mirrors that include a first convex mirror, a second mirror, a third mirror, a fourth mirror, a fifth mirror, and a sixth mirror in order of reflections of light, wherein the light incident upon the third mirror from the second mirror intersects with the light incident upon the fifth mirror from the fourth mirror.

Abstract: A scan type display optical system is disclosed in which the position and inclination of an image formed by projection light is made variable. The scan type display optical system comprises an optical scanning member for deflecting and scanning light, and a projection optical system which includes a plurality of optical surfaces containing a reflective surface. The projection optical system projects light from the optical scanning member. An incidence range of light from the optical scanning member to a first optical surface on which the light is incident initially out of the plurality of optical surfaces is variable.

Abstract: A projection optical system is disclosed with which undistorted images can be obtained at any image position within a specification range, and whose projection angle can be changed. The projection optical system includes a plurality of optical elements and a first optical system constituted by at least one of the plurality of optical elements having the ability to form an image with light onto a predetermined surface different from the projection surface. A projection image of the original image can be moved by rotating a first optical element of the plurality of optical elements substantially around a center of an exit pupil position of the first optical system as the rotation center.

Abstract: The optical system disclosed in this specification is a variable power optical system for enlarging and projecting a reduction side object onto an enlargement side image plane, or reducing and projecting an enlargement side object onto a reduction side image plane. This variable power optical system includes a first optical component having a reflecting curved surface, and a second optical component disposed more toward the reduction side than the first optical component. The second optical component has a plurality of movable lens units, and the variable power optical system effects a variable power operation by movement of the plurality of lens units. If ray was traced from the reduction side toward the enlargement side, the second optical component forms an image of a reduction side conjugate point on the enlargment side than an optical surface of the first optical component that is most adjacent to the reduction side.

Abstract: A catoptric projection optical system for projecting a pattern on an object surface onto an image surface includes plural mirrors, wherein a second mirror from the image surface through the optical path receives convergent pencil of rays, and has a paraxial magnification of −0.14 or smaller.

Abstract: A catoptric projection optical system for projecting a reduced size of a pattern on an object surface onto an image surface and for serving as an imaging system that forms an intermediate image between the object surface and image surface, includes six or more mirrors, wherein a position of an exit pupil with respect to the intermediate image is located between the object surface and image surface, and wherein the largest angle between principal rays and an optical axis for angles of view at the position of the exit pupil is sin−1NA or smaller, where NA is a numerical aperture at the side of the image surface.

Abstract: A cataoptric projection optical system for projecting a reduced size of a pattern on an object plane onto an image plane includes first, second, third and fourth mirrors from the image plane along an optical path, wherein the third and fourth mirrors are located between the first mirror and second mirror.