Abstract: A circumferential angle adjustment device for a generatrix of a cylindrical lens, comprising: a lens holding tube which holds the cylindrical lens; an outer peripheral tube in which the lens holding tube is arranged on an inner peripheral side thereof; a cam member which is provided on an outer peripheral side of the lens holding tube and has a cam surface eccentric with respect to an axis intersecting with an optical axis of the lens holding tube, and a cam member engaging portion which is formed in the outer peripheral tube and engages with the cam member in the circumferential direction of the optical axis, wherein the lens holding tube is supported with respect to the outer peripheral tube in at least three directions at regular intervals in the circumferential direction of the optical axis.

Abstract: A mirror holding mechanism includes: a reflection mirror, a mirror holding member, and a cam member. The mirror holding member has two side surface portions sandwiching the reflection mirror in an X direction. In the side surface portion, a guide hole through which a shaft portion protruding from the reflection mirror to an outer side in the X direction is formed so as to pass through the side surface portion. The guide hole is formed into a long hole longitudinally extending in a Y direction. The cam member is disposed on an outer side of the side surface portion in the X direction and rotatably held by the side surface portion. On the cam member, a cam surface with which a distal end part of the shaft portion comes into contact is formed. When the cam member rotates, the shaft portion moves in the Y direction.

Abstract: An imaging device is provided that includes: a lens barrel, an element holder adhesively secured to one end of the lens barrel while holding an imaging element; and an elastic body disposed between the lens barrel and the element holder. The lens barrel has formed thereon a projection projecting toward the element holder. The element holder has formed therein an insertion hole into which the projection is inserted. The elastic body is fitted to the projection with the projection inserted into an insertion hole in the elastic body. In the imaging device, an outer peripheral surface of the projection and an inner peripheral surface of the insertion hole are in contact with each other, and the element holder is in contact with the elastic body on the periphery of the insertion hole. An adhesive is filled between the projection and the insertion hole.

Abstract: There is provided a lens system includes a first optical system and forms an intermediate image, which has been formed inside the first optical system by light from an input side, into a final image. The first optical system includes a first subsystem, with the first subsystem including a first lens that is disposed at a position closest to the intermediate image on the input side and moves during focusing and a second lens that is disposed at a position closest to the intermediate image on the output side and moves during focusing.

Abstract: A projection optical system (10) projects from a first image plane (5) on a reducing side to a second image plane (6) on an enlargement side. The projection optical system (10) includes a first optical system (11) that includes a plurality of lenses and forms a first intermediate image (51) formed inside the first optical system (11) by light incident from the reducing side into a second intermediate image (52) on the enlargement side of the first optical system (11); a second optical system (12) that includes a first reflective surface (M1) with positive refractive power which is positioned further to the enlargement side than the second intermediate image (52); and a glass block (30) that is disposed between the first optical system (11) and the first reflective surface (M1), the glass block (30) passing light rays from the first optical system (11) to the second intermediate image (52).

Abstract: An optical diaphragm device includes: diaphragm blades each having a first fixing boss protruding from one surface of a first planar plate toward a side in a first direction and a moving boss protruding from the other surface of the first planar plate toward a side in a second direction; light leakage prevention blades each having a second fixing boss protruding from one surface of a second planar plate toward the side in the first direction and forming a pair with the diaphragm blade; a drive ring with cam grooves; and a housing body accommodating the diaphragm blades, light leakage prevention blades and drive ring. A second cam groove is formed on the light leakage prevention blade. The moving boss of the diaphragm blade is inserted into the second cam groove of the light leakage prevention blade, and is inserted into the first cam groove of the drive ring.

Abstract: There is provided a projection optical system (1) that projects from a first image plane on a reducing side to a second image plane on an enlargement side, including a first refractive optical system (11) that includes eight lenses (L1) to (L8) and forms a first intermediate image (31) on the enlargement side using light that is incident from the reducing side, a second refractive optical system (12) that includes six lenses (L9) to (L14) and forms the first intermediate image (31) on the reducing side into a second intermediate image (32) on the enlargement side, and a first reflective optical system (20) that includes a first reflective surface (21a) with positive refractive power that is positioned closer to the enlargement side than the second intermediate image (32).

Abstract: There is provided an optical system (1) that includes at least one lens. The at least one lens includes a first lens (L21), through an eccentric part of the first lens with respect to an optical axis (7), a light beam for forming an image passing eccentrically with respect the optical axis. At least one surface of the first lens includes a plurality of regions with different optical characteristics that can be switched by a focusing unit (52) rotating the first lens about the optical axis as an axis of rotation. A typical example of a plurality of regions include a first region for forming an image at a near distance and a second region for forming an image at a far distance.

Abstract: In order to provide a projection lens barrel and a projection display device that are capable of correcting the optical characteristics of a plurality of lens groups, a projection lens barrel, comprising a lens optical system causing light from an image display element to be formed as a projected image on a screen, also comprises correction mechanisms that move each of at least two lens groups along an optical axis and correct the optical characteristics to be corrected, said lens groups each having different optical characteristics for correction in order to suppress reduction in image quality of a projected image caused by changes in optical characteristics caused by temperature changes in the projection lens barrel.

Abstract: A zoom lens unit includes a zoom ring that has a scale indicating a focal length of the zoom lens unit, an indicator member that points a desired value on the scale, and a selection mechanism that is configured to select one of first and second moving states of the indicator member. In the first moving state, the indicator member moves as the zoom ring rotates. Further, in the second moving state, the indicator member moves without rotating the zoom ring.

Abstract: An optical device includes a fixed tube that has a straight groove extending in a first direction parallel to an optical axis of the optical device, a cam ring that has a cam groove extending in a second direction intersecting to the first direction, a cam follower that is engaged with the straight groove and the cam groove, a lens unit that moves in conjunction with the cam follower in the first direction, and an auxiliary cam follower that is engaged with the straight groove and that is not engaged with the cam groove. When the fixed tube and the cam ring relatively rotate, the lens unit moves in the first direction. Further, the lens unit is fixed to the cam follower and the auxiliary cam follower.

Abstract: A projection optical system (10) projects from a first image plane (5) on a reducing side to a second image plane (6) on an enlargement side. The projection optical system (10) includes a first optical system (11) that includes a plurality of lenses and forms a first intermediate image (51) formed inside the first optical system (11) by light incident from the reducing side into a second intermediate image (52) on the enlargement side of the first optical system (11); a second optical system (12) that includes a first reflective surface (M1) with positive refractive power which is positioned further to the enlargement side than the second intermediate image (52); and a glass block (30) that is disposed between the first optical system (11) and the first reflective surface (M1), the glass block (30) passing light rays from the first optical system (11) to the second intermediate image (52).

Abstract: Provided is a lens device, including: a lens barrel, a control unit mounted to the lens barrel; and a cable having one end connected to the control unit. In the lens device, a cable housing groove configured to house a part of the cable therein in such a manner that the part of the cable is wound around the cable housing groove from a radially outer side of the lens barrel is formed along a circumferential direction of the lens barrel so as to be exposed.

Abstract: There is provided a lens system includes a first optical system and forms an intermediate image, which has been formed inside the first optical system by light from an input side, into a final image. The first optical system includes a first subsystem, with the first subsystem including a first lens that is disposed at a position closest to the intermediate image on the input side and moves during focusing and a second lens that is disposed at a position closest to the intermediate image on the output side and moves during focusing.

Abstract: A projection optical system (10) projects from a first image plane (5) on a reducing side to a second image plane (6) on an enlargement side. The projection optical system (10) includes a first optical system (11) that includes a plurality of lenses and forms a first intermediate image (51) formed inside the first optical system (11) by light incident from the reducing side into a second intermediate image (52) on the enlargement side of the first optical system (11); a second optical system (12) that includes a first reflective surface (M1) with positive refractive power which is positioned further to the enlargement side than the second intermediate image (52); and a glass block (30) that is disposed between the first optical system (11) and the first reflective surface (M1), the glass block (30) passing light rays from the first optical system (11) to the second intermediate image (52).

Abstract: Provided is an illumination module capable of preventing a light exit surface from being darker along peripheral edge portions as though having borders. An illumination module (1) includes: a light guiding plate (20), which has an end surface (21) and a first principal surface (23); a light source (30) configured to emit light that enters the end surface (21); and a diffusion plate (50), which has alight incident surface (55) and a light exit surface (56). The diffusion plate (50) includes a protruding part (51), which protrudes toward the light guiding plate (20) side and the light source (30), which is positioned so as to face a peripheral edge portion (26) on the end surface (21) side of the light guiding plate (20), and which has a light incident surface (52) into which light exiting the peripheral edge portion (26) enters.

Abstract: A projection optical system (2) projects from a DMD (7) on a reducing side onto a screen (9) on an enlargement side, and includes: a first refractive optical system (10) that forms a first intermediate image (51) on the enlargement side using light incident from the reducing side; a second refractive optical system (20) that forms the first intermediate image (51) on the reducing side into a second intermediate image (52) on the enlargement side; and a first reflective optical system (30) including a first reflective surface (31a) with positive refractive power that is positioned on the enlargement side of the second intermediate image (52), wherein the second refractive optical system (20) includes a first focus lens group (61) that moves when focusing is carried out, and the first focus lens group (61) includes at least one lens (L13) included in the second refractive optical system (20).