Abstract: An image-sensor fixing structure includes an imaging optical system; and an image sensor configured to receive light of an image formed by the imaging optical system. The image sensor has an imaging surface includes an effective region, in which light of an image formed by the imaging optical system is received, and a peripheral region outside the effective region. A body member holding the imaging optical system is fixed to the peripheral region.

Abstract: An optical system includes two imaging optical systems disposed symmetrically with each other; two holders to hold the imaging optical systems; and two shaft members including a first shaft member and a second shaft member. The first shaft member is held by the first hole of the one holder, and the second shaft member is held by the second hole of the one holder. The first shaft member is disposed in the second hole of the other holder with a movement of the first shaft member restricted in each direction perpendicular to a direction in which the first holes are opposed to the second holes. The second shaft member is disposed in the first hold of the other holder with the second shaft member movable in only a certain direction within a plane perpendicular to the direction in which the first holes are opposed to the second holes.

Abstract: An image-sensor fixing structure includes an imaging optical system; and an image sensor configured to receive light of an image formed by the imaging optical system. The image sensor has an imaging surface includes an effective region, in which light of an image formed by the imaging optical system is received, and a peripheral region outside the effective region. A body member holding the imaging optical system is fixed to the peripheral region.

Abstract: A joint structure includes: a plurality of holes open to opposing surfaces of two members that oppose to each other, the holes each being filled with a fluid or powder filler (U) in a state where the holes communicate with each other, such that the two members are relatively fixed by the filler. The holes of the two members each have an inner surface that is wider in cross-sectional direction at a location distant from openings of the holes than at a location close to the openings.

Abstract: An optical system including two imaging optical systems and two holders including one holder to hold one imaging optical system and other holder to hold the other one imaging optical system. Each holder includes a lens positioner to determine a position of a lens constituting each imaging optical system, and two contacts disposed apart from the lens positioner. When the one holder is combined with the other holder, the two contacts of the one holder contact the two contacts of the other holder with the lens maintained at the position determined by the lens positioner of each holder.

Abstract: An optical system includes two imaging optical systems disposed symmetrically with each other; two holders to hold the imaging optical systems; and two shaft members including a first shaft member and a second shaft member. The first shaft member is held by the first hole of the one holder, and the second shaft member is held by the second hole of the one holder. The first shaft member is disposed in the second hole of the other holder with a movement of the first shaft member restricted in each direction perpendicular to a direction in which the first holes are opposed to the second holes. The second shaft member is disposed in the first hold of the other holder with the second shaft member movable in only a certain direction within a plane perpendicular to the direction in which the first holes are opposed to the second holes.

Abstract: A joint structure includes: a plurality of holes open to opposing surfaces of two members that oppose to each other, the holes each being filled with a fluid or powder filler (U) in a state where the holes communicate with each other, such that the two members are relatively fixed by the filler. The holes of the two members each have an inner surface that is wider in cross-sectional direction at a location distant from openings of the holes than at a location close to the openings.

Abstract: A camera body includes a plurality of body-side bayonet lugs which are provided on the peripheral edge of an opening; and a protrusion which is positioned in a circular-arc opening formed between adjacent body-side bayonet lugs of the body-side bayonet lugs, the distance between the protrusion and either of adjacent two body-side bayonet lugs of the body-side bayonet lugs being shorter than each of the lens-side bayonet lugs; and a body-side mount surface with which the lens-side bayonet surface comes into contact from the front side when the lens-side bayonet lugs are positioned immediately behind the body-side bayonet lugs.

Abstract: A camera body includes a body-side bayonet lug, wherein a lens-side bayonet lug of a lens barrel is positioned immediately behind the body-side bayonet lug when the lens barrel is mounted to the camera body; an opposed surface formed on the rear surface of the body-side bayonet lug and positioned immediately in front of the lens-side bayonet lug; a body-side mount surface positioned in front of the opposed surface and with which the lens-side bayonet surface comes into contact; and a body-side contact portion, the front end of which contacts the rear end of the lens-side contact portion when the opposed surface faces the lens-side bayonet lug, the front end of the body-side contact portion being positioned in front of the opposed surface and behind the body-side mount surface.

Abstract: A camera body includes body-side bayonet lugs concentric with lens-side bayonet lugs, circular-arc openings, a circular arc protrusion positioned inside the camera body and projecting forward and concentric with the body-side bayonet lugs, body-side contact portions provided and arranged on the front end surface of the circular arc protrusion and come into contact with lens-side contact portions which are provided on the lens barrel, and rearward biasers provided immediately behind two of the body-side bayonet lugs to bias and move the lens-side bayonet lugs rearward, wherein two of the body-side contact portions located at both ends in the lengthwise direction and the two rearward biasers lie on radial-direction extension lines of the circular arc protrusion, respectively, as viewed in an optical axis direction.

Abstract: A gear mechanism having a smaller diameter and achieving an accurate automatic drive includes a central gear supported on a rotational shaft, first and second side gears coaxially positioned on both sides of the central gear, planetary bevel gears supported within side surfaces of the central gear, and sun bevel gears respectively formed on the inner side surfaces of the first and second side gears which are engaged with the planetary bevel gears. At least one of the first and second side gears is provided with a torque adjuster for adjusting the torque of the side gear(s).

Abstract: A varifocal lens barrel includes a plurality of lens groups, each of which are linearly movable in the optical axis direction thereof without rotating about the optical axis during a zooming operation and during a focusing operation, including a base barrel which is linearly movable in the optical axis direction by rotation of a zoom operational ring, wherein lens frames of the respective lens groups are each supported by the base barrel.

Abstract: A camera body includes a plurality of body-side bayonet lugs which are provided on the peripheral edge of an opening; and a protrusion which is positioned in a circular-arc opening formed between adjacent body-side bayonet lugs of the body-side bayonet lugs, the distance between the protrusion and either of adjacent two body-side bayonet lugs of the body-side bayonet lugs being shorter than each of the lens-side bayonet lugs; and a body-side mount surface with which the lens-side bayonet surface comes into contact from the front side when the lens-side bayonet lugs are positioned immediately behind the body-side bayonet lugs.

Abstract: A camera body includes body-side bayonet lugs concentric with lens-side bayonet lugs, circular-arc openings, a circular arc protrusion positioned inside the camera body and projecting forward and concentric with the body-side bayonet lugs, body-side contact portions provided and arranged on the front end surface of the circular arc protrusion and come into contact with lens-side contact portions which are provided on the lens barrel, and rearward biasers provided immediately behind two of the body-side bayonet lugs to bias and move the lens-side bayonet lugs rearward, wherein two of the body-side contact portions located at both ends in the lengthwise direction and the two rearward biasers lie on radial-direction extension lines of the circular arc protrusion, respectively, as viewed in an optical axis direction.

Abstract: A camera body includes a body-side bayonet lug, wherein a lens-side bayonet lug of a lens barrel is positioned immediately behind the body-side bayonet lug when the lens barrel is mounted to the camera body; an opposed surface formed on the rear surface of the body-side bayonet and positioned immediately in front of the lens-side bayonet lug; a body-side mount surface positioned in front of the opposed surface and with which the lens-side bayonet surface comes into contact; and a body-side contact portion, the front end of which contacts the rear end of the lens-side contact portion when the opposed surface faces the lens-side bayonet lug, the front end of the body-side contact portion being positioned in front of the opposed surface and behind the body-side mount surface.

Abstract: A water-resistant structure of a lens barrel includes a sealing member that seals an annular gap between inner and outer annular members, wherein the sealing member is positioned in a vicinity of an open end of the outer annular member and is fixed to one of the inner and outer annular members to be slidable on the other of the inner and outer annular members, and a drain groove formed on the inner annular member and positioned alongside the sealing member at a position closer to the open end of the outer annular member than the sealing member. Furthermore, a frictional resistance of a first sealing member produced between a secondary annular member and a manually-rotatable annular members is greater than a frictional resistance of the second sealing member that urges one of two of the manually-rotatable annular members to follow a rotation of the other thereof when rotated.

Abstract: A varifocal lens barrel includes a plurality of lens groups, each of which are linearly movable in the optical axis direction thereof without rotating about the optical axis during a zooming operation and during a focusing operation, including a base barrel which is linearly movable in the optical axis direction by rotation of a zoom operational ring, wherein lens frames of the respective lens groups are each supported by the base barrel.

Abstract: A gear mechanism having a smaller diameter and achieving an accurate automatic drive includes a central gear supported on a rotational shaft, first and second side gears coaxially positioned on both sides of the central gear, planetary bevel gears supported within side surfaces of the central gear, and sun bevel gears respectively formed on the inner side surfaces of the first and second side gears which are engaged with the planetary bevel gears. At least one of the first and second side gears is provided with a torque adjuster for adjusting the torque of the side gear(s).

Abstract: A water-resistant structure of a lens barrel includes a sealing member that seals an annular gap between inner and outer annular members, wherein the sealing member is positioned in a vicinity of an open end of the outer annular member and is fixed to one of the inner and outer annular members to be slidable on the other of the inner and outer annular members, and a drain groove formed on the inner annular member and positioned alongside the sealing member at a position closer to the open end of the outer annular member than the sealing member. Furthermore, a frictional resistance of a first sealing member produced between a secondary annular member and a manually-rotatable annular members is greater than a frictional resistance of the second sealing member that urges one of two of the manually-rotatable annular members to follow a rotation of the other thereof when rotated.

Abstract: An interchangeable lens selectively mountable to a first-type camera body and a second-type camera body, the first-type camera body including a first mount ring to which the interchangeable lens is mountable, the second-type camera body including a second mount ring to which the interchangeable lens is mountable, an outer diameter of the second mount ring being smaller than an outer diameter of the first mount ring. The interchangeable lens includes an annular packing made of a resilient material. An inner peripheral surface of the annular packing is positioned radially outside the second mount ring when the interchangeable lens is mounted to the second-type camera body. The inner peripheral surface of the annular packing is positioned radially inside an outer peripheral surface of the first mount ring when the interchangeable lens is mounted to the first-type camera body.