Abstract: A zoom lens barrel assembly includes a first lens group including first and second sub-lens groups; a second lens group; a sub-lens group switching mechanism for moving the first or second sub-lens group away from the other in a short focal length photographing range, and toward the other in a long focal length photographing range; and a zoom cam mechanism having front and rear lens group cam grooves. The rear lens group cam groove includes first and second portions corresponding to the short and long focal length photographing ranges, respectively, the first and the second portions connected to each other via a discontinuous portion. The front lens group cam groove includes a non-linear portion which corresponds to the short focal length photographing range and provides a non-linear path, and a linear portion which corresponds to the long focal length photographing range and provides a linear path.

Abstract: A lens barrel is provided which includes a stationary frame and a second holding frame. One end of a second main rod is attached to the second holding frame with a sleeve between. One end of the second sub rod is fixed to the second holding frame, and the other ends of the second main rod and second sub rod are attached to the stationary frame so that the second main rod and second sub rod can freely slide. Consequently, the second holding frame is borne while being permitted to freely advance or withdraw relative to the stationary frame without rotating by the main rod and second sub rod. The main rod is fixed to neither the stationary frame nor lens holding frame but can slide by itself. Therefore, even when the lens barrel is collapsed, the main rod will not jut backward beyond the stationary frame.

Abstract: An optical-position adjusting device for an optical unit comprises a movement-conversion mechanism that converts a rotational movement of a rotary wheel cylinder into a linear movement of a lens barrel, and an optical-position adjusting mechanism that positions the lens barrel with respect to the rotary wheel cylinder. The optical-position adjusting mechanism has a ring and a fixing member. The ring is fit on the lens barrel in such a manner that the lens barrel can be moved along the central axis thereof. The ring is non-rotatable relative to the lens barrel. The fixing member is provided for fixing the ring to a frame in such a manner that the ring can be released from the frame.

Abstract: A lens barrel includes a first frame member supporting a first lens group, a second frame member supporting a second lens group and being capable of movable relative to the first frame member along an optical axis, a cam follower in the first frame member, a cam frame member having a cam groove engaged with the cam follower to permit the first frame member to be movable along the optical axis, a contact portion which is provided for the second frame member and can come into contact with the cam follower, and a pushing member pushing the second frame member in the direction the cam follower comes into contact with the contact portion. The pushing member pushes the second frame member and the contact portion comes into contact with the cam follower. Thus, the position of the second lens group with respect to the first lens group can be restricted.

Abstract: A driving device includes a first member, an annular second member arranged outside the first member, an annular first plate for connecting the first and second members to each other, and an annular second plate for connecting the first and second members to each other. The first and second members are moved relative to each other by supplying or exhausting a fluid into or from a space surrounded by the first and second members and the first and second plates. Also, at least one of (i) an inner diameter a1 of a portion of the second member at which the second member is connected to the first plate is different from an inner diameter a2 of a portion of the second member at which the second member is connected to the second plate and (ii) an outer diameter b1 of a portion of the first member at which the first member is connected to the first plate is different from an outer diameter b2 of a portion of the first member at which the first member is connected to the second plate.

Abstract: An external helicoid thread is provided which includes a helicoid thread having a first ridge whose both flanks are formed at a first flank angle, and a helicoid thread having a second ridge whose both flanks are formed at a second flank angle which is different from the first flank angle. An internal helicoid thread is kept in screwed-state engagement with the external helicoid threads. And in a lens barrel obtained using a connection based on such internal and external helicoid threads, the connection provided by these helicoid threads can remain secured even if a sudden outside force is applied to the lens barrel.

Abstract: An image sensor module with a zooming function is disclosed. The sensor module consists of first and second barrels for respectively holding condensing lenses used for image capture, and a housing having a guide channel at a sidewall thereof and movably and stably receiving the first extensions of the first and second barrels in the guide channel such that the first and second barrels are moved along a focusing axis of the condensing lenses. The sensor module also has a motor for generating a rotating force, a motor gear formed on the output shaft of the motor, and a means for controlling the interval between the first and second barrels by converting a rotating action of the motor gear into a linear movement of the first and second barrels in a horizontal direction. In the sensor module used in a variety of electronic apparatuses, the condensing lenses are movable to change their positions, thus accomplishing a zooming effect while precisely condensing light beams to produce clear images.

Abstract: A speed variation mechanism includes a base, a first sliding member, a second sliding member and a fixing device. The base has a first surface. The first sliding member is able to slide on the first surface and has a second surface. The second sliding member is able to slide on the second surface and has a third surface. The third surface is in contact with a driven member to drive an optical device. The fixing device can selectively fix the first sliding member to the base or the second sliding member. When the second sliding member is pushed, the speed variation mechanism of the invention can provide different moving speeds for the driven member to drive the optical device by fixing the first sliding member to the base or the second sliding member.

Abstract: A mechanism element for optical devices has a light-incident part on which light having a wavelength of 700 nm or more is incident, and the light-incident part is made of aluminum or an alloy of aluminum or magnesium. An anodizing process treatment to form an anodized coating is performed at least on the light-incident part, and then the surface of the light-incident part is colored to be black by a secondary electrolytic coloring method.

Abstract: Lens barrel or an optical apparatus with a lens barrel comprising: a lens unit having an optical axis and forming an optical image, the lens unit having a fixed lens component and a movable lens component; and a lens housing for containing the lens unit, the lens housing having a first housing and a second housing divided in a direction along the optical axis; wherein: the first housing has a lens-holding portion for holding the fixed lens component; and the second housing has a pickup-device holding portion for holding an image pickup device for taking the optical image obtained by the lens unit.

Abstract: A lens barrel comprises a first cylindrical member having an inner peripheral surface, and a second cylindrical member internally fitted to the first cylindrical member and having an outer peripheral surface that facing in a radial direction to the inner peripheral surface. One of the inner peripheral surface and the outer peripheral surface is formed with first and second helical grooves extending in an axial direction in parallel with each other, and a third groove extending in only a circumferential direction continuously from one side ends of the first and second grooves. The other of the inner peripheral surface and the outer peripheral surface are formed with first and second protruded portions engaging respectively with the first and second grooves in alignment in the circumferential direction and enabling relative rotations between the first and second cylindrical members and relative movements in the axial direction therebetween.

Abstract: A lens barrel device includes a lens mounted in a lens frame that is threaded into an annular adjusting ring. The adjusting ring is coupled using a bayonet to a lens barrel. The lens barrel includes first and second flanges on the inner periphery of the lens barrel that define grooves for receiving bayonet projections on the annular adjusting ring. The bayonet coupling structure of the annular adjusting ring includes semispherical projections for elastically engaging inner walls of the grooves and also includes a rotation regulating stopper for engaging an end wall of an opening in one of the inner flanges so as to regulate rotation of the annular adjusting ring, and hence the lens, relative to the lens barrel. The end wall includes a groove for receiving a jig that can release the bayonet coupling structure of the annular adjusting ring from the lens barrel.

Abstract: A varifocal lens barrel includes movable lens groups including a focusing lens group which is moved by different amounts of movement at different focal lengths, a focus operation ring, a focus lens frame which supports the focusing lens group, a guide ring positioned around the focus lens frame, a bottomed focusing cam groove formed on the focus lens frame or the guide ring, a spherical follower which is supported by the focus lens frame or the guide ring, a biasing member for pressing the spherical follower against the bottomed focusing cam groove, and an adjustment mechanism which varies a relative moving range of the spherical follower in the bottomed focusing cam groove in accordance with a variation of the focal length to vary an amount of movement of the focusing lens group per unit of rotation of the focus operation ring.

Abstract: Embodiments of the present invention provide a lens mounting apparatus for mounting a lens to a substrate having a sensor in a sensor housing mounted on the substrate. The apparatus comprises a lens mount member including a lens mount body coupled with the lens housing. The lens mount body includes a locating element configured to register the lens mount body to the sensor housing mounted on the substrate. The lens mount member includes a flexible mounting element configured to be attached to the substrate and permit movement of the lens mount body toward and away from the sensor housing. A focus ring includes a slip ring portion coupled with the coupling surface of the lens housing.

Abstract: The invention relates to a magnetic drive focusing device with at least one lens within a chamber and an adjuster with magnets outside the chamber. Positioned between the lens and the chamber is a second sleeve with helical guide paths. As the adjuster is moved outside the chamber, the magnetic field within the chamber causes the lens within the chamber to move. As the lens rotates, non-magnetic guides which ride in the helical guide paths force the lens to move axially within the device.

Abstract: A collimator positioning system for positioning a collimator on a base member. The positioning system includes a first support rod and a second support rod. The first support rod has a general elongated length with at least two cam surfaces spaced from each other along the length. The second support rod is movable relative to the first support rod to form a variable collimator support area therebetween. The support rods are adapted to be moved relative to each other for varying an angle of inclination or a height of the collimator on the base member.

Abstract: A cam mechanism includes a linear guide barrel provided with a linear guide projection at one end thereof, extending radially outwards; a cam barrel fitted on the linear guide barrel, rotatable relative to the linear guide barrel and movable along the optical axis with the linear guide barrel, the cam barrel being provided with a cam groove on an inner surface thereof; a linear guide slot formed on the linear guide barrel extending parallel to the optical axis; at least one lens frame positioned inside the linear guide barrel; a projection formed on the lens frame to be slidably engaged in the linear guide slot; and a cam follower formed on the projection to be engaged in the cam groove. The linear guide projection and the linear guide slot are formed on the linear guide barrel at the same circumferential position of the linear guide barrel.

Abstract: A lens frame guiding mechanism of a zoom lens includes lens frames having projections which extend radially outwards, wherein a cam follower is formed on each projection; a linear guide barrel; linear guide slots formed on the linear guide barrel parallel to the optical axis, wherein the projections of each lens frame are respectively engaged in the linear guide slots to be slidable therealong; a cam barrel fitted outside the linear guide barrel to be relatively rotatable about the optical axis thereto; and bottomed cam grooves formed on an inner peripheral surface of the cam barrel, in which the cam followers of a corresponding lens frame are respectively engaged. The lens frames are moved in the direction of the optical axis, without rotating about the optical axis, to change a focal length of said zoom lens via rotation of said cam barrel.

Abstract: A lens barrel of the present invention includes a first zoom frame and a second zoom frame which are moved frontward and rearward by a cam frame. The first zoom frame holds a first lens group, and the second zoom frame contacts and presses a second-group frame. Four guide shafts are fixed to the first zoom frame, and directly and slidably support the second-group frame which holds a second lens group or a third-group frame which holds a third lens group. Therefore, the deviation between the optical axes of the second lens group and the third lens group from the first lens group is reduced. In the lens barrel, the supporting structure of the frame members is simplified, the supporting accuracy of the frame members is increased, and the misalignment of the optical axes of the lens groups is prevented.

Abstract: A multi-stage-extension zoom lens barrel assembly includes an inner peripheral helicoid ring having a first helicoid formed on the outer periphery thereof which is engaged with a second helicoid formed on an inner periphery of an outer peripheral helicoid ring; a first linear guide ring provided in the inner peripheral helicoid ring and is relatively rotatable and integrally movable therewith in the optical axis direction; and a first outer barrel for covering the first linear guide ring, the first outer barrel being supported on the first linear guide ring so as to relatively rotate and move together in the optical axis direction therewith, wherein the first outer barrel is detachably attached to the inner peripheral helicoid ring, the first outer barrel being integrally rotatable about the optical axis and integrally movable along the optical axis with the inner peripheral helicoid ring.

Abstract: A lens barrel includes first and second lens groups guided in an optical axis direction without rotating about the optical axis, first and second support frames which support the first and second lens groups and include first and second cam followers, respectively; and a cam ring which is rotatable about the optical axis and includes a cam groove. The cam groove is formed as a continuous groove and includes first and second groove portions via which the first and second cam followers are guided to move the first and second lens groups, respectively. One of the first cam follower and the second cam follower enters one of the first groove portion and the second groove portion after passing through the other of the first groove portion and the second groove portion in a preparation stage of the lens barrel.

Abstract: A lens shutter mechanism includes, between front and rear support frames having photographing apertures, shutter sectors which open and close the photographing apertures; a shutter drive ring which is rotatable about the optical axis to drive the shutter sectors; diaphragm sectors which change an aperture diameter of the photographing apertures independently of the shutter sectors; and a diaphragm drive ring which is rotatable about the optical axis to drive the diaphragm sectors. The shutter drive ring and the diaphragm drive ring are located at different radial positions and at the same optical axis position. One and the other of the shutter drive ring and the diaphragm drive ring is provided with an inner flange and an outer flange respectively, which radically project toward each other so as to overlap in the axial direction, and engage so as to be relatively slidable in the circumferential direction.

Abstract: A zoom lens barrel assembly includes a first lens group including first and second sub-lens groups; a second lens group; a sub-lens group switching mechanism for moving the first or second sub-lens group away from the other in a short focal length photographing range, and toward the other in a long focal length photographing range; and a zoom cam mechanism having front and rear lens group cam grooves. The rear lens group cam groove includes first and second portions corresponding to the short and long focal length photographing ranges, respectively, the first and the second portions connected to each other via a discontinuous portion. The front lens group cam groove includes a non-linear portion which corresponds to the short focal length photographing range and provides a non-linear path, and a linear portion which corresponds to the long focal length photographing range and provides a linear path.

Abstract: A zoom lens barrel assembly includes a plurality of lens barrels including a rearmost lens barrel, secured to a camera body, and a frontmost lens barrel. At least one adjacent pair of lens barrels are connected to each other via a helicoid structure. The frontmost lens barrel and a first adjacent lens barrel are connected to each other via a cam structure. The helicoid structure allows the adjacent pair of the lens barrels to rotate and move in an optical axis direction relative to each other while the zoom lens barrel assembly moves from a retracted position to a minimally extended position for a photographing operation. At least a portion of the helicoid structure includes a slip region which allows the pair of adjacent lens barrels to rotate without relatively moving along the optical axis.

Abstract: A lens guide mechanism includes a lens frame which supports a photographing lens group, the lens frame including a plurality of guide holes extending in a direction parallel with an optical axis; a support barrel in which the lens frame is provided; a gear holding member which is provided at a front end of the support barrel; a gear train which is held between the support barrel and the gear holding member, the gear train constituting a drive mechanism for the lens frame; and a plurality of linear movement guide rods provided in the gear holding member, which extend through the guide holes of the lens frame and support the lens frame to move linearly in the optical axis direction relative to the support barrel.

Abstract: A lens barrel is provided with a front lens group facing a subject, that moves only during zooming, and an internal focusing lens group, different from the front lens group, moving at least during focusing. A first cam ring having a cam groove for causing the front lens group to move, and a second cam ring that is separate from the first cam ring, is driven by the same drive source as the first cam ring, rotates together with the first cam ring, and has a cam groove for causing lens groups other than the front lens group to move, are also provided.

Abstract: A zoom lens includes a cam barrel having first and second cam grooves formed on an inner peripheral surface thereof; and first and second lens frames having first and second cam followers, respectively engaged with the first and the second cam grooves. The cam dead end of the first cam groove and the second cam follower insertion opening of the second cam groove are formed at the same circumferential position. Upon assembly, the first cam follower is inserted into the first leading section via a first cam follower insertion opening, and the second cam follower is inserted into the second leading section via a second cam follower insertion opening.

Abstract: A zoom lens barrel includes a through groove which is provided on a first cylindrical member; a radial projection provided on a second cylindrical member; and a roller which is supported by the radial projection and is fitted in the through groove. The through groove has an opening width on the inner diameter of the first cylindrical member which is greater than the opening width on the outer diameter thereof. The roller is provided with an slip-off prevention portion whose diameter is greater than the opening width of the through groove on the outer diameter of the first cylindrical member, but smaller than the opening width on the inner diameter. The through groove is provided with a large width portion at which the roller is fitted into, so that the slip-off prevention portion is located in the through groove.

Abstract: Lens barrel or an optical apparatus with a lens barrel comprising:

Abstract: A lens driving apparatus includes an intermediate barrel expandable and collapsible in an optical axis direction, for moving a rear lens group in the optical axis direction along with expanding and collapsing; a movable barrel, concentric with the intermediate barrel, expandable and collapsible with respect to the intermediate barrel along with the expanding and collapsing of the intermediate barrel, for moving a front lens group in the optical axis direction when expanding from the intermediate barrel; and a click ball for holding the front lens group when the movable barrel collapses, so as to move the front lens group together with the intermediate barrel. As a consequence, when the movable barrel collapses, the front lens group can be held and moved together with the intermediate barrel so the focus can be adjusted appropriately, and the apparatus can be made smaller at a lower cost.

Abstract: A zoom lens barrel includes a cylindrical member which is provided with a female helicoid; a split helicoid cylinder having a rear helicoid ring portion which is provided with a male helicoid which is screw-engaged with the female helicoid, and a front cylindrical portion which is detachably connected to the rear helicoid ring portion so as not to relatively rotate; a linear movement cylinder provided in the split helicoid cylinder so as to move in the optical axis direction; and a connecting structure for connecting the linear movement cylinder to the split helicoid cylinder so as to relatively rotate and so as not to relatively move in the optical axis direction, so that the rear helicoid ring portion and the front cylindrical portion of the split helicoid cylinder maintain connected by the connecting structure without being disconnected in the optical axis direction.

Abstract: A lens driving device which does not make larger an apparatus in which the device is installed, which ensures a longer span for preventing a tilt of a lens therein, and which allows an easy access to the lens after assemblage is disclosed. The lens driving device includes a stationary board; a lens frame holding a lens group; a moving body like a flat plate one end of which is fixed to the lens frame in which the moving body is slid over the stationary board; and a rod, extending in an optical direction of the lens, which guides the moving body in the optical direction and is driven by a piezoelectric element. In the arrangement, the other end of the flat plate is frictionally held by the rod over a predetermined distance in the optical direction. When the piezoelectric element is supplied with a voltage with a predetermined waveform, the lens frame is driven in the direction of the optical axis by the moving body frictionally engaging the rod.

Abstract: A lens barrel includes a fixed lens tube of cylindrical shape and a plurality of operation parts of push type, wherein the plurality of operation parts are interconnected by a ring-shaped elastic member and are attached to the fixed lens tube. This structural arrangement of the lens barrel effectively simplifies assembly processes in the manufacture of lens barrels.

Abstract: There is provided an optical device which comprises a fixed barrel, a movable cam ring, and collars and abutments. The movable cam ring is shifted relative to the fixed barrel to move an optical unit, the movable cam ring being fitted to the fixed barrel. Collars and abutments can be engaged with each other when the movable cam ring is in a predetermined positional relationship with respect to the fixed barrel. The collars and abutments preventing the movable cam ring from being disengaged from the fixed barrel and displaced in a direction along an optical axis relative to the fixed barrel.

Abstract: In a collapsing mechanism of the projecting lens apparatus, when a focus ring is moved to the back over a moving range for adjusting the focus, the focus ring is connected to a zoom ring. Then, the zoom ring rotates by following the focus ring which moves to the back, and a first and a second zoom lenses are moved to the back over a moving range for adjusting the zoom. Therefore, the focus ring completely collapses into a body of a projector.

Abstract: A shift mechanism includes first and second ring bodies which are relatively rotatable; a shift cam surface formed on the first ring body on an end surface thereof which faces the second ring body, the shift cam surface being inclined with respect to a circumferential direction of the first ring body; a follower projection formed on the second ring body for engaging with the shift cam surface; and a rotating mechanism for relatively rotating the first and second ring bodies. The shift cam surface and the follower projection are arranged to move the first and second ring bodies toward and away from each other in the axial direction as the first and second ring bodies are relatively rotated. An annular rib is formed along the circumference of the first ring body outside the shift cam surface over the follower projection of the second ring body.

Abstract: A lens barrel comprises first and second cylinders, a base, a single motor, a feed screw, a rotation mechanism, a helicoid mechanism, and a drive gear for transmit a drive force of the motor to the feed screw and the rotation mechanism. The drive gear comprises a cylindrical gear and a shaft gear having a shaft inserted in the cylindrical gear. The cylindrical gear and the shaft gear rotating about a common rotation axis. The cylindrical gear is interposed between the rotation mechanism and the motor, and the shaft gear is interposed between the feed screw and the motor. Accordingly, zooming and focusing can be made by one motor, increasing density and integration and providing excellent space efficiency.

Abstract: A small, light weight drive apparatus is capable of driving an object in a predetermined direction, as well as being capable of micromotion in a rotation direction and in an orthogonal direction to the predetermined direction. A drive apparatus drives an object within a two dimensional plane including a first axis and a second axis orthogonal to the first axis. The drive apparatus includes a first stage on which the object is placed. A micromotion mechanism slightly drives the first stage in a direction of the second axis and in a rotation direction about a third axis orthogonal to the two-dimensional plane. A second stage holds the first stage without physically contacting the first stage. A non-contact holding mechanism disposed between the first stage and the second stage holds the first stage to the second stage in a non-contact manner allowing for micromotion of the first stage in the second axis direction and in the rotation direction relative to the second stage.

Abstract: A barrier opening and closing apparatus for opening and closing a barrier according to a rotation of a lens barrel containing an optical lens system comprises a ring member disposed rotatable about an optical axis of the optical lens system and adapted to open and close the barrier according to a rotation thereof, whereas the ring member forms a plurality of rotational force transmitting parts extending rearward therefrom in parallel to the optical axis so as to be engaged with the lens barrel. The ring member is directly rotated by way of the plurality of rotational force transmitting parts engaged with the lens barrel, so as to open and close the barrier, whereby the cost of apparatus can be cut down.

Abstract: A laser diode module of an optical scanner includes a circuit board; a case fastened to the circuit board after its position is adjusted, the case having a laser diode embedded therein; and a slider guide fastened to the case. The slider guide has a barrel shaped; upwardly directed guide surface and a pair of further guide surfaces which are formed at either side of the barrels shaped surface. The three guide surfaces extend generally parallel to a laser beam produced by the diode. A lens holder having a body and a pair of guide pieces is seated on the barrel shaped guide surface of the slider guide such that it can slide thereon is formed with an inserting hole. The pair of guide pieces are on either side of the body and are seated on the pair of further guide surfaces of the slider guide, respectively.

Abstract: Guide grooves are formed on the inner periphery of a first lens barrel along an optical axis, and guide couplers are coupled with the guide grooves to guide the first lens barrel along the optical axis. Inclined parts are formed on both sides of the guide grooves, and inclined parts are formed on both sides of the guide couplers. Thus, the guide couplers do not easily come off from the guide grooves even if a pressure is applied to them.

Abstract: A zoom lens barrel that performs zooming by moving a plurality of lens groups, which constitute a photo-taking optical system, by interlocking the lens group with each other. The zoom lens barrel includes a first frame supporting a first lens group and a second frame supporting a second lens group. A cam tube supports both the first frame and the second frame so that the frames can relatively move in the direction of the optical axis of the optical system. A drive cam is provided in the cam tube and has a cam that has a first cam region for moving the first frame in the direction of the optical axis and a second cam region for moving the second frame in the direction of the optical axis. The drive cam is formed so that the first frame and the second frame may commonly use partial regions of the first cam region and the second cam region at the time of performing the zooming.

Abstract: In this zoom lens barrel, its cam ring has three sets of three cam grooves for advancing or retracting a first group frame, a focus frame and third group frame. The three cam grooves include a cam follower introducing groove connected to ends of two cam grooves for the focus frame and third group frame and a joint groove for joining two cam grooves for the first group frame and the focus frame. When inserting a cam follower of the first group frame into the cam groove, after it is inserted into the introducing groove, it is passed through the cam groove for the focus frame and then, passed through the joint groove and fit to the cam groove for the first group frame. Further, when inserting the cam followers of the focus frame and third group frame into the cam groove, after it is inserted from the introducing groove, it can be fit to the focus frame and third group frame separately.

Abstract: This lens barrel comprises a first group frame supported by two first guide shafts and a second guide shaft such that it is capable of being advanced or retracted, a focus frame, a focus frame holding portion, and a third group frame. The first guide shafts are bonded and supported by the focus holding frame in parallel such that both ends thereof are exposed. The first group frame and the third group frame are supported slidably by both end portions. Further, the second guide shaft supports the focus frame slidably. An end of the second guide shaft is supported through a short fitting length while it is not fixed to the first group frame and the other end thereof is supported slidably by the third group frame through a short fitting length. Therefore, in this lens barrel, the accuracy in advancement and retraction of respective members is excellent and an efficiency of storage space is excellent thereby contributing to reduction of the size, achieving compactness.

Abstract: A floating lens barrel includes a stationary barrel which can be connected to a camera body, a rotation ring which is rotatably supported by the stationary barrel and which is rotated in accordance with the focusing operation, a female helicoid ring provided on the stationary barrel, a front lens support ring which supports a focusing front lens group and which is guided to move linearly in the optical axis direction, a male helicoid ring which is supported by the front lens support ring so as to rotate relative thereto but not to move in the optical axis direction relative to the front lens support ring, a combination of rotation transmission grooves and pins for transmitting the rotation of the rotation ring to the male helicoid ring, and a rear lens support ring which holds a focusing rear lens group and which is guided to move linearly in the optical axis direction by the front lens support ring, in accordance with a cam groove formed in the male helicoid ring.

Abstract: A zoom lens comprises a fixed cylinder, an outer movable cylinder, and an inner movable cylinder which is provided in the interior thereof with a shutter and a front group lens. The front group lens is fixed by an outer frame which is fastened with the shutter. The outer frame retains a chain plate capable of being driven by a rotary plate of the shutter. The chain plate has an indicator portion. The inner movable cylinder is provided in the inner wall thereof with a reference indicium, which is level with and aligned with the indicator portion of the chain plate at such time when the zoom lens is located at various focusing positions.

Abstract: A structure, used for a collapsible type of zoom lens barrel provided in a camera, which makes advantageous a wiring of an electric wire extending between a side of a camera body and an electrically driven device which is installed within a space inside the zoom lens barrel, in an attempt of effective use of the space therein. The zoom lens barrel includes: a stationary lens barrel, rectangular in cross section, fitting to a rectangular exposure window of a picture frame in front of a film set inside the camera body; a first movable lens barrel, rectangular in cross section, slidably fitted inside the stationary lens barrel; and a second movable lens barrel, circular in cross section, slidably fitted inside the first movable lens barrel, in which the zoom lens barrel can take a projecting state and a retracting state. In the retracting state, the space is formed between the first movable lens barrel and the second movable lens barrel, in which space the electrically driven device is positioned.

Abstract: A hybrid optical barrel as a projection optical unit includes a plurality of cell groups disposed in series along an optical axis, each cell group including at least a cell unit and each cell unit including a lens and a cell holding the lens. The optical barrel also includes a connecting barrel member carrying the plurality of cell groups, the connecting barrel member being made of a material with a CTE<3.0 ppm.degree.C. such as Invar, Ultra Low Expansion.TM. glass, Zerodur glass, or silicon carbide. The connecting barrel member may comprise a plurality of sub-barrels disposed in series along the optical axis. Alternatively, the connecting barrel member may comprise a plurality of spacing members. Therefore, during an axial displacement of the optical barrel caused by a temperature change, relative axial dimensions of the sub-barrels or the spacing members remain substantially constant, thereby reducing an overall displacement of the lenses within the plurality of cell groups.

Abstract: A zoom lens barrel has a stationary barrel, a rotatable cam barrel, a straight-movable barrel, a first lens component, and a second lens component. The stationary barrel is fixed to a camera body. The rotatable cam barrel is screw-engaged with the stationary barrel and moves along the optical axis while rotating about the optical axis. The straight-movable barrel is guided straight along the optical axis by the stationary barrel and is fitted to the rotatable cam barrel so as to be movable together therewith along the optical axis and rotatable independently thereof about the optical axis. The first lens component is fixed to the straight-movable barrel. The second lens component is guided straight along the optical axis by the straight-movable barrel and is cam-coupled to the rotatable cam barrel so as to be cam-driven along the optical axis by the rotatable cam barrel.

Abstract: A secondary focuser which facilitates minute and measured incremental changes of the focal length within a limited travel distance is disclosed. The secondary focuser is used to micro focus telescopes for astro photography. A method of constructing the micro focuser comprises the following steps: constructing a housing having an open central axis therethrough; slidably disposing a travelling inner sleeve within the housing; and, mounting and arranging a micrometer head on the housing. When the micrometer head is turned the inner sleeve travels within the housing finely adjusting an axial length therethrough. In a preferred aspect of the invention the micrometer head is configured to turn about an axis generally perpendicular to the central axis through the housing, pivoting a rocker arm so that when one end portion of the rocker arm is moved in a radial direction, the other end moves in a direction generally parallel to the central axis, thereby longitudinally shifting the travelling sleeve.