Abstract: A zooming adjustment mechanism including a holder, a zoom ring, at least two rollers, a first resilient sheet, and a second resilient sheet is provided. The zoom ring is confined to the holder and coupled to a zoom bar. The rollers are respectively confined to a groove of the holder and in contact with a bottom surface of the zoom ring. The first resilient sheet is disposed on a first side of the holder, and each end of the first resilient sheet leans against a roller. The second resilient sheet is disposed on a second side of the holder, and each end of the second resilient sheet leans against a roller. A projection lens module including the zooming adjustment mechanism is also provided.

Abstract: A zoom lens barrel assembly includes: a zoom ring having a cylindrical shape, and comprising an inlet portion formed in a boundary of one end thereof and a first protrusion; a guide ring disposed around the zoom ring, and comprising a first guide hole through which the first protrusion passes, and movably supporting the zoom ring in an axial direction, and a second guide hole; and a cylinder disposed in the zoom ring, for moving and rotating between a position where the cylinder is accommodated in the zoom ring and a position where the cylinder moves away from the zoom ring in the axial direction, and comprising a second protrusion that passes through the second guide hole, accommodated in the inlet portion at the position where the cylinder is accommodated, and pressing one end of the inlet portion when the cylinder moves away from the zoom ring.

Abstract: A zoom lens barrel includes a base member 1001, a linear cylinder 700 fixed on the base member 1001, a cam cylinder 800 configured to be rotatable with respect to the linear cylinder 700, a ball member 701 and a pin member 702 provided on the linear cylinder 700, and a plurality of optical component units. The cam cylinder 800 includes a cam groove 800d that the ball member 701 contacts and that determines a position in an optical axis direction of the cam cylinder 800 with respect to the linear cylinder 700, and a cam groove 800i that the pin member 702 engages with in a radial direction of the cam cylinder 800 and that the pin member 702 contacts in two directions different from each other that are the optical axis direction.

Abstract: A lens module includes a holder, a connecting loop, engaging pins, an adjustment ring, a fixing pin; and a lens unit. The holder includes a barrel having a receiving space. The barrel defines sliding slots. The adjustment ring defines guiding grooves and a stopping slot. The connecting loop is received in the receiving space, the adjustment ring is sleeved over the barrel, and each engaging pin is secured with the connecting loop, an end of each engaging pin passing through a corresponding sliding slot and into a corresponding guiding groove. The fixing pin passes through the stopping slot and fixed with the barrel, the lens unit is secured with the connecting loop, the adjustment ring is rotated relative to the holder, and the engaging pin slides along the guiding groove, to cause the lens unit to axially move without rotating relative to the holder.

Abstract: This invention discloses a zoom lens structure and a camera lens. The zoom lens structure comprises a shifting barrel, a zoom-driving ring, a fixed barrel and a focus-driving ring. The shifting barrel has a first guiding protrusion. The zoom-driving ring is arranged at a periphery of the shifting barrel, and having a groove-hole and a first-driving part. The fixed barrel is arranged at a periphery of the zoom-driving ring, and having a first groove. The first guiding protrusion is passed through the groove-hole and inserted into the first groove. The focus-driving ring is coupled to an end of the zoom-driving ring and having a second-driving part at the outer edge thereof. By a driving module driving the first-driving part and the second-driving part at the same time, the zoom-driving ring and the focus-driving ring are rotated forwardly or reversely for zooming or focusing.

Abstract: A lens barrel includes lens units movable in an optical axis direction, a driving unit including an annular actuator in which an optical axis serves as a rotation center, a first cam cylinder disposed inwardly of the annular actuator and including a circular cylindrical base portion and a large-diameter portion, a second cam cylinder configured to drive at least one of the lens units by rotating at an outer-peripheral side of the large-diameter portion, and a rotation transmitting portion provided at the large-diameter portion and transmitting rotation of the first cam cylinder to the second cam cylinder, wherein, in a state in which the length of the lens barrel is shortest, a portion of the second cam cylinder and the rotation transmitting portion overlap in the optical axis direction a lens unit holding frame that is closest to an object side.

Abstract: A zoom lens includes a focus cam for converting a first rotation amount given upon a focus operation into a movement of the focus lens group and further converting a second rotation amount given upon a zoom operation into the movement of the focus lens group, and a focus cam follower engaged with the focus cam and operable to move in the focus cam. The focus cum follower rotates in the focus cum according to the rotation amount of the zoom driving unit to move the focus lens group. A lift amount of the focus cam is defined so that a rotation amount of the focus driving unit from a far end position to an infinite position when the rotation position of the zoom driving unit is at a wide-angle end becomes larger than the rotation amount when the rotating position of the zoom driving unit is at a telephoto end.

Abstract: A lens barrel capable of distributing, upon receipt of the impact of, e.g., dropping, a torque load so as not to concentrate on a particular linear movement key and groove for linearly moving a barrel member, thereby suppressing occurrence of a failure. The lens barrel has a fixed barrel (8) and a third lens group barrel (3). In a movement region of the third lens group barrel (3) moving in the optical direction relative to the fixed barrel (8), each of a set of a first linear movement groove (8c) and a first linear movement key (3c) and a set of a second linear movement groove (8d) and a second linear movement key (3d) has a mutually engageable region and a mutually disengageable region, and a set of a groove (8e) and a projection (3e) has not a mutually engageable region.

Abstract: A lens barrel and a projector of the invention are provided with a fixed cylinder, and a cam ring mounted on the fixed cylinder. A first projection and a second projection are provided on one of the fixed cylinder and the cam ring, and a first rotation restricting portion and a second rotation restricting portion are provided on the other of the fixed cylinder and the cam ring. The first rotation restricting portion restricts rotation of the cam ring by abutting contact with the first projection when the cam ring is rotated in a first direction, and the second rotation restricting portion restricts rotation of the cam ring by abutting contact with the second projection when the cam ring is rotated in a second direction opposite to the first direction.

Abstract: The present invention is directed to an improved inner focusing zoom lens barrel that implements a zoom ratio as high as 15×±? and that ensures a well-balanced cam configuration for the smooth zooming and focusing. The inner focusing zoom lens barrel includes a fixed barrel; a focusing cam barrel, a linear shuttle barrel, and a first cam barrel laid one over another in this order inside the fixed barrel; and a zoom linkage ring, a second cam barrel, and a 1st-lens-group sliding barrel laid one over another in this order outside the fixed barrel.

Abstract: A linear guide mechanism of a lens barrel, the lens barrel including a rotatable ring, and a linearly movable member which holds an optical element and moves linearly in an optical axis direction by rotation of the rotatable ring, the linear guide mechanism includes a plurality of partial linear guide members which linearly guide the linearly movable member in the optical axis direction. A movement range of the linearly movable member in the optical axis direction is shared by a plurality of different movement ranges, via which the linearly movable member is linearly guided in the optical axis direction by the plurality of partial linear guide members, respectively.

Abstract: A lens barrel includes lens units movable in an optical axis direction, a driving unit including an annular actuator in which an optical axis serves as a rotation center, a first cam cylinder disposed inwardly of the annular actuator and including a circular cylindrical base portion and a large-diameter portion, a second cam cylinder configured to drive at least one of the lens units by rotating at an outer-peripheral side of the large-diameter portion, and a rotation transmitting portion provided at the large-diameter portion and transmitting rotation of the first cam cylinder to the second cam cylinder, wherein, in a state in which the length of the lens barrel is shortest, a portion of the second cam cylinder and the rotation transmitting portion overlap in the optical axis direction a lens unit holding frame that is closest to an object side.

Abstract: A zoom lens barrel assembly including: a first zoom ring comprising a first protrusion; a guide ring disposed around the first zoom ring comprising a first guide slot through which the first protrusion passes, and a second guide slot; a second zoom ring comprising a second protrusion, and movable in an axial direction; a first cylinder comprising a guide groove into which the second protrusion inserts, and a third protrusion passing through the second guide slot, and disposed between the first and second zoom rings; a second cylinder disposed around the guide ring comprising a fourth protrusion, a first groove portion into which the first protrusion inserts, and a second groove portion into which the third protrusion inserts, and supporting the first zoom ring and the first cylinder; and an external cylinder disposed around the second cylinder and comprising a third groove portion into which the fourth protrusion inserts.

Abstract: A zoom lens barrel assembly includes: a zoom ring having a cylindrical shape, and comprising an inlet portion formed in a boundary of one end thereof and a first protrusion; a guide ring disposed around the zoom ring, and comprising a first guide hole through which the first protrusion passes, and movably supporting the zoom ring in an axial direction, and a second guide hole; and a cylinder disposed in the zoom ring, for moving and rotating between a position where the cylinder is accommodated in the zoom ring and a position where the cylinder moves away from the zoom ring in the axial direction, and comprising a second protrusion that passes through the second guide hole, accommodated in the inlet portion at the position where the cylinder is accommodated, and pressing one end of the inlet portion when the cylinder moves away from the zoom ring.

Abstract: A zooming adjustment mechanism including a holder, a zoom ring, at least two rollers, a first resilient sheet, and a second resilient sheet is provided. The zoom ring is confined to the holder and coupled to a zoom bar. The rollers are respectively confined to a groove of the holder and in contact with a bottom surface of the zoom ring. The first resilient sheet is disposed on a first side of the holder, and each end of the first resilient sheet leans against a roller. The second resilient sheet is disposed on a second side of the holder, and each end of the second resilient sheet leans against a roller. A projection lens module including the zooming adjustment mechanism is also provided.

Abstract: A lens barrel includes lens units movable in an optical axis direction, a driving unit including an annular actuator in which an optical axis serves as a rotation center, a first cam cylinder disposed inwardly of the annular actuator and including a circular cylindrical base portion and a large-diameter portion, a second cam cylinder configured to drive at least one of the lens units by rotating at an outer-peripheral side of the large-diameter portion, and a rotation transmitting portion provided at the large-diameter portion and transmitting rotation of the first cam cylinder to the second cam cylinder, wherein, in a state in which the length of the lens barrel is shortest, a portion of the second cam cylinder and the rotation transmitting portion overlap in the optical axis direction a lens unit holding frame that is closest to an object side.

Abstract: A lens barrel includes: a holding frame; a cam ring rotatable relative to the holding frame around a rotational axis substantially parallel to an optical axis of an imaging optical lens system; and a cam follower and a cam groove that engage with each other so that the holding frame and the cam ring move relative to each other along the optical axis when the holding frame and the cam ring are rotated relative to each other.

Abstract: A lens barrel includes a cam ring driving unit including a moving frame, a linear driving unit that includes a holding frame configured to hold an image pickup element, and a guide bar that is engaged with the holding frame, extends in the optical axis direction, and is configured to guide a linear movement of the holding frame in the optical axis direction, and an intermediate fixing lens unit configured still in the optical axis direction. The cam ring driving unit is arranged on an object side of the intermediate fixing lens unit, the linear driving unit is arranged on an image pickup element side of the intermediate fixing lens unit, and the lens barrel is configured dividable into the cam ring driving unit, the linear driving unit, and the intermediate fixing lens unit.

Abstract: A lens barrel includes a first retaining member to retain a first driving unit, a second retaining member to retain a second driving unit, a fixing cylinder in which the first retaining member and the second retaining member are disposed adjacent to each other in an optical axis direction, and a cam cylinder disposed about an outer circumference of the fixing cylinder rotatable in a circumferential direction, and the first and the second retaining members are moveable in the fixing cylinder following a same trajectory according to a rotation of the cam cylinder.

Abstract: A lens barrel unit includes a lens holding cylinder, a cam cylinder, and a straightforward movement cylinder. The lens holding cylinder includes a ring-shaped step that projects outward in a radial direction. In an image pickup state, a surface of the ring-shaped step which is an end of an object side in the ring-shaped step is closer to an object than a surface of the straightforward movement cylinder which is an end of an object side in the straightforward movement cylinder.

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 zoom lens barrel includes a base member 1001, a linear cylinder 700 fixed on the base member 1001, a cam cylinder 800 configured to be rotatable with respect to the linear cylinder 700, a ball member 701 and a pin member 702 provided on the linear cylinder 700, and a plurality of optical component units. The cam cylinder 800 includes a cam groove 800d that the ball member 701 contacts and that determines a position in an optical axis direction of the cam cylinder 800 with respect to the linear cylinder 700, and a cam groove 800i that the pin member 702 engages with in a radial direction of the cam cylinder 800 and that the pin member 702 contacts in two directions different from each other that are the optical axis direction.

Abstract: A zoom lens barrel includes a fixed barrel in which a first mark is indicated, and a zoom operation ring in which a second mark is indicated, the zoom operation ring being supported on the fixed barrel. The zoom lens barrel has a focal length region where at least angles of view of a circular fisheye and a full-frame fisheye can be formed, and one of the angles of view of the circular fisheye and the full-frame fisheye is formed for a predetermined image-pickup element size in a focal length where the first mark and the second mark are matched to each other.

Abstract: A lens barrel having an image forming optical system including a first optical system and a second optical system which is moveable independently from the first optical system, a first driving portion which drives the first optical system during a magnification changing operation of the image forming optical system, and a second driving portion which drives the second optical system during the magnification changing operation, along with driving the second optical system during a focus adjustment of the image forming system.

Abstract: A lens barrel unit including a lens barrel which has a plurality of lens groups and is set to a photographing state by moving at least a part of the lens groups to an object side and to a collapsed state by moving the at least the part of the lens groups to an image plane side and storing the lens groups, the lens barrel unit includes: a first supporting frame which retains at least one lens group of the lens groups; a second supporting frame which retains the first supporting frame movably in an optical axis direction of the lens barrel; a first supporting frame moving section which moves the first supporting frame in the optical axis direction of the lens barrel; and a fixed cylinder in which a main shaft which is capable of moving the second supporting frame in the optical axis direction of the lens barrel is provided.

Abstract: A lens barrel includes a driven ring, a follower provided on the driven ring, a rotational transfer ring including a circumferential groove having no axial-direction component and a rotational transfer groove including an axial-direction component, a guide ring, and a cam groove formed on the guide ring for guiding the driven ring via the follower. Rotation of the driven ring is prevented when the follower is engaged in the circumferential groove so that the driven ring is held at a non-photographing position. When the follower is engaged in the rotational transfer groove, the driven ring is moved along the cam groove between the non-photographing position and a ready-to-photograph position. Opposed wall surfaces in the circumferential groove determine a position of the follower when the driven ring moves between the non-photographing position and the ready-to-photograph position.

Abstract: A lens barrel includes at least two cam tubes, and an operation based on the rotation of an operation ring actuates the two cam tubes to move a lens group. The lens barrel includes a first cam tube that drives part of the lens group in response to an operation based on the rotation of the operation ring, and a second cam tube that moves part of the lens group in the optical axis direction in response to the operation based on the rotation of the operation ring. The second cam tube rotates at a speed different from that of the first cam tube.

Abstract: An optical transmission device including a driving unit having a transmitting member, a guide member, a frame, a clipping unit and a flexible member is disclosed. The clipping unit has a main clip engaging with one side of the transmitting member, and a sub-clip engaging with the other side of the transmitting member. The flexible member pushes the main clip to the sub-clip, so that the sub-clip radially and axially approaches the transmitting member.

Abstract: The lens apparatus includes a guide barrel including a guide groove portion penetrating through a circumferential wall of the guide barrel, and a cam barrel disposed rotatably and including a penetrating cam groove portion penetrating through a circumferential wall of the cam barrel and a non-penetrating cam groove portion not penetrating therethrough. The apparatus further includes a first holding member holding a first optical element and moved in an optical axis direction by the guide groove portion and the penetrating cam groove portion with rotation of the cam barrel, a second holding member holding a second optical element and moved in the optical axis direction by the guide groove portion and the non-penetrating cam groove portion with the rotation of the cam barrel, and an adjusting mechanism used for adjusting a position of one of the first and second optical elements relative to that of the other.

Abstract: The lens apparatus includes a first barrel member, a second barrel member, a first rolling bearing and a second rolling bearing. The second barrel member includes a cam for moving a lens unit in an optical axis direction, is disposed inside or outside the first barrel member and rotatable around an optical axis with respect to the first barrel member. The first rolling bearing prevents relative displacements of the first and second barrel members in the optical axis direction and in a radial direction. The first rolling bearing is rotatable between the first and second barrel members. The second rolling bearing prevents the relative displacement of the first and second barrel members in the radial direction. The second rolling bearing is rotatable between the first and second barrel members. The first and second rolling bearing are arranged at positions away from each other in the optical axis direction.

Abstract: A lens barrel includes lens units movable in an optical axis direction, a driving unit including an annular actuator in which an optical axis serves as a rotation center, a first cam cylinder disposed inwardly of the annular actuator and including a circular cylindrical base portion and a large-diameter portion, a second cam cylinder configured to drive at least one of the lens units by rotating at an outer-peripheral side of the large-diameter portion, and a rotation transmitting portion provided at the large-diameter portion and transmitting rotation of the first cam cylinder to the second cam cylinder, wherein, in a state in which the length of the lens barrel is shortest, a portion of the second cam cylinder and the rotation transmitting portion overlap in the optical axis direction a lens unit holding frame that is closest to an object side.

Abstract: An imaging apparatus includes of a lens holder arranged concentrically with an imaging element; a lens barrel having an imaging lens removably inserted from the leading end section side of the lens holder; a cover removably fitted at the leading end section of the lens holder; and a cam mechanism section arranged on the barrel, the lens holder and the cover so that the barrel turns around the optical axis to the imaging element and that the barrel moves in the optical axis direction. The cam mechanism section includes a first cam surface formed on the inner circumference surface of the lens holder; a cam protruding section formed on the outer circumference surface of the lens barrel; and a second cam surface formed on the inner surface of the cover. The cam mechanism section smoothly turns the barrel around the optical axis and moves the barrel in the optical axis direction.

Abstract: A rotationally extendable structure of a lens barrel includes a stationary ring; a rotational ring, supported by the stationary ring to move in an optical axis direction while rotating and includes a peripheral gear at the rear end thereof; and a rotational-ring drive gear. The rotational-ring drive gear includes a long gear portion, formed long enough to mesh with the peripheral gear over an entire moving range of the rotational ring, and a large-diameter gear portion at the rear end of the long gear portion. The rotational ring is provided in a rear end thereof with a large-diameter-gear accommodating recess. When the rotational ring is moved to a rearward movement extremity in the optical axis direction, the large-diameter gear portion enters into the large-diameter-gear accommodating recess so that the large-diameter gear portion coincides with the peripheral gear with respect to the optical axis direction.

Abstract: The lens barrel includes a lens frame and a cam frame. The lens frame has a body supporting a lens element in the optical system, at least three through-holes formed in the lens frame body, at least three cam members arranged on the lens frame body and at least one protruding member that protrude from the lens frame body. The cam frame has a body, at least three projection members extending from the cam frame body and inserted through the through-holes, at least three cam grooves formed in the cam frame body and the projection members to guide the cam members and to movably support the lens frame with respect to the cam frame body. The cam frame also has at least one auxiliary groove to guide the protruding member. One end of the auxiliary groove is disposed in the circumferential direction between two adjacent projection members.

Abstract: A zoom lens includes a variable aperture-stop mechanism positioned in front or behind an aperture-control lens group; a first rotation imparting member, which rotates an opening/closing ring of the variable aperture-stop mechanism by a relative movement between the variable aperture-stop mechanism and the first rotation imparting member in the optical axis direction so as to hold an adjustable aperture of the variable aperture-stop mechanism at a small aperture size when the aperture-control lens group moves within in the zooming range; and a second rotation imparting member, which rotates the opening/closing ring by a relative movement between the variable aperture-stop mechanism and the second rotation imparting member to open and hold the adjustable aperture at a large aperture size when the aperture-control lens group moves to the accommodated position, at which the aperture-control lens group is partly positioned in the adjustable aperture held at the large aperture size.

Abstract: A zoom lens includes a focus cam for converting a first rotation amount given upon a focus operation into a movement of the focus lens group and further converting a second rotation amount given upon a zoom operation into the movement of the focus lens group, and a focus cam follower engaged with the focus cam and operable to move in the focus cam. The focus cum follower rotates in the focus cum according to the rotation amount of the zoom driving unit to move the focus lens group. A lift amount of the focus cam is defined so that a rotation amount of the focus driving unit from a far end position to an infinite position when the rotation position of the zoom driving unit is at a wide-angle end becomes larger than the rotation amount when the rotating position of the zoom driving unit is at a telephoto end.

Abstract: A retractable zoom lens includes a holder, at least one movable barrel assembly received in the holder, a holding frame received in the movable barrel assembly, and a slide barrel engaged with the holding frame. The holding frame can move along the optical axis along with the movement of the movable barrel assembly. The movable barrel assembly is movable along an optical axis of the retractable zoom lens, and the slide barrel is slidable along a direction substantially perpendicular to the optical axis during an object image captured by an image pickup device of the retractable zoom lens.

Abstract: It is an object of the present invention to provide a lens barrel in which operability for a user is increased and a reduction in parts is achieved while provided with a manual operating member.

Abstract: A zoom lens assembly and zoom lens module are provided, including a first lens, a second lens, a plurality of guiding blocks, a sheathing tube, a plurality of linking members and an adjusting tube. The first lens includes a plurality of curved surfaces disposed on a second lens surface toward a first lens surface. The second lens includes a plurality of driving rods disposed on a third lens surface and abutting the curved surfaces. The guiding blocks are respectively fixed on the first lens. The sheathing tube sheathes the first lens and the second lens and comprises a plurality of guiding notches to receive the guiding blocks, and a plurality of slits. The linking members pass through the slits and are fixed on the second lens. The adjusting tube sheathes the sheathing tube and comprises a plurality of driving notches to receive the linking members.

Abstract: A lens position adjusting device of a lens barrel includes a stationary ring, and a manual rotating ring which is screw-engaged with the stationary ring to be manually rotatable about an optical axis to move a movable lens group in the optical axis direction, wherein the manual rotating ring includes an operating ring member; and a sub-ring member which is screwed into the stationary ring, wherein the operating ring member and the sub-ring member are coupled to each other so that a relative rotation position therebetween about the optical axis is adjustable.

Abstract: A zoom lens includes a cam roll, straight-forward units, lens groups, a driving unit, a detecting unit and a micro-processing unit. The lens groups moved by the cam roll sequentially varies from a receiving status to a zeroing status, a macro shooting-distance status and a wide shooting-distance status. A datum point of the cam roll corresponds to the zeroing status of the lens groups. The detecting unit includes an impeller, a detecting portion and a photonic sensor. When the photonic sensor detects the datum point of the cam roll, the micro-processing unit determines the position of the datum point of the cam roll and to reset the rotation count of the impeller. When the photonic sensor detects a skew point of the cam roll, the micro-processing unit determines and amends the rotation count of the impeller to be equal to a predetermined value.

Abstract: A lens barrel includes a linear guide member, a linearly advancing/retracting member guided by the linear guide member along an optical axis of an imaging optical system to be movable between operating and retracted positions, and a displaceable element supported by the linearly advancing/retracting member to be movable between an on-axis position in which the displaceable element is positioned on the optical axis and an off-axis displaced position in which the displaceable element is displaced from the optical axis. The linear guide member includes a linear guide projection which extends in a direction parallel to the optical axis to be engaged with the linearly advancing/retracting member. The linear guide projection includes an accommodation through-cutout formed through the linear guide projection in a radial direction, at least part of the displaceable element entering the accommodation through-cutout when the linearly advancing/retracting member is in the retracted position.

Abstract: An addendum of a gear portion and a tip end of a first cam follower are located on similar-diameter cylindrical planes centering at a center axis of a cam ring. A gear housing recess is provided in an inner peripheral surface of a fixed ring. A bottom surface of a first-cam-ring-movement cam groove engaging with the first cam follower, and a bottom surface of the recess are located on similar-diameter cylindrical planes centering at a center axis of the fixed ring. A release portion is provided at the inner peripheral surface of the fixed ring to provide communication between a protruding position cam groove portion of the first-cam-ring-movement cam groove and the recess. At the protruding position of the cam ring, a portion of the gear portion near the first cam follower passes through the release portion and is located inside the protruding position cam groove portion.

Abstract: A lens barrier mechanism of a lens barrel includes a cam ring including a forward-projecting portion; a linearly movable barrel provided outside the cam ring and moves linearly by rotating the cam ring; a barrier blade provided in the linearly movable barrel and movable in an operating plane orthogonal to the optical axis to open and close an opening at the front of the linearly movable barrel; and a barrier drive mechanism which opens and shuts the barrier blade when the lens barrel moves from/to the accommodated state to/from the ready-to-photograph state, respectively. A range of opening/shutting operation of the barrier blade extends radially outside an inner periphery of the forward-projecting portion. In the accommodated state, the forward-projecting portion intersects the operating plane of the barrier blade but is positioned outside the range of opening/shutting operation of the barrier blade.

Abstract: An engagement pawl of a linear-movement guide ring engages with an engagement groove of a cam ring, and hence the cam ring is supported by the linear-movement guide ring non-movably in an optical-axis direction. When the cam ring is rotated, a cam pin of a second group moving frame moves in the optical-axis direction along a cam groove formed in an inner periphery of the cam ring. The cam groove includes a plurality of first cam grooves and a plurality of second cam grooves. The engagement groove of the cam ring intersects with the second cam groove. The engagement pawl has a width larger than a groove width of the second cam groove intersecting with the engagement groove.

Abstract: A lens barrel is provided. The lens barrel includes a first cylinder that includes at least one continuous groove on an interior surface thereof. The at least one continuous groove includes a trough of a helicoidal screw and a circumferential groove formed in a circumferential direction with respect to the first cylinder and formed in continuation with the trough of the helicoidal screw. The lens barrel also includes a second cylinder that includes a crest of a helicoidal screw that engages with the trough of the helicoidal screw and the circumferential groove and that is formed on outer circumference of the second cylinder. The crest of the helicoidal screw is formed of first material. A part of the crest of the helicoidal screw includes a reinforcement structure formed of a second material that is a different material from the first material.

Abstract: An objective optical system is configured to be suitable to be implemented at a tip of an endoscope. The objective optical system is provided with a first lens unit having a first lens barrel and a first optical system including plurality of lens elements assembled in the first lens barrel, and a second lens unit having a second lens barrel and a second optical system including a plurality of lens elements. The first lens unit or the second lens unit includes an alignment lens which is movable in a direction perpendicular to the optical axis thereof. The alignment lens is a lens most sensitive with respect to an alignment error among the plurality of lenses included in the first optical system.

Abstract: A lens barrel includes a first barrel, a second barrel having an inner face facing an outer face of the first barrel, and a circuit board supported by the second barrel. The circuit board is provided between the first barrel and the second barrel. The circuit board comprises a first circuit board and a second circuit board, the first circuit board is provided as substantially parallel with an optical axis of the optical system, the first circuit board and the second circuit board are provided at a crossing direction.

Abstract: The present invention is directed to an improved inner focusing zoom lens barrel that implements a zoom ratio as high as 15×±? and that ensures a well-balanced cam configuration for the smooth zooming and focusing. The inner focusing zoom lens barrel includes a fixed barrel; a focusing cam barrel, a linear shuttle barrel, and a first cam barrel laid one over another in this order inside the fixed barrel; and a zoom linkage ring, a second cam barrel, and a 1st-lens-group sliding barrel laid one over another in this order outside the fixed barrel.

Abstract: A cam mechanism includes a cam ring, and a linearly movable frame movable supporting an optical element. The cam grooves are located at different positions in the optical axis direction and which trace a same reference cam diagram. All cam grooves are partial cam grooves each having at least one end opening at at least one of opposite ends of the cam ring, so as not to include an entire portion of the reference cam diagram. Cam followers are located at different positions at least in the optical axis direction and are respectively engageable in the cam grooves. At least one of the cam followers remains engaged in a corresponding cam groove while at least one of the other of the cam followers comes out of the end opening and is disengaged therefrom when the linearly movable frame moves to movement limit in the optical-axis direction.