Abstract: A tilt adjustment device K for objective lenses which comprises: a positioning stand 52 for supporting a holder 3 which fixedly holds a first objective lens 1; at least three pins 57a, 57b, and 57c for supporting an inferior surface of an edge of a second objective lens 2 by each tip of the pins; a pin fixedly supporting member 57 for fixedly supporting the ends of the pins; tilt adjusting means for tilting the pin fixedly supporting member 57 so that the second objective lens 2 is tilt-adjusted around a principal point center with respect to an inferior surface of an edge of the first objective lens 1; and a press member 54 for pressing a superior surface of the second objective lens 2, which can be removed after the second objective lens 2 is fixed.

Abstract: A replacement apparatus for an optical element mounted between two adjacent optical elements in a lithography objective has a holder for the optical element to be replaced, which holder can be moved into the lithography objective through a lateral opening in a housing of the same.

Abstract: In a lens holder included in an objective lens actuator, a first holding hole to hold a first objective lens and a second holding hole to hold a second objective lens are arranged. In the first holding hole, two supporting portions to support the first objective lens are arranged and they are disposed oppositely in a radial direction to sandwich an optical axis of the first objective lens. In the second holding hole, two supporting portions to support the second objective lens are arranged and they are disposed oppositely in a tangential direction to sandwich an optical axis of the second objective lens.

Abstract: A lens holder is disclosed which holds a plurality of objective lenses, the lens holder holding the plurality of objective lenses so as to be arranged with a composite gravity center position of the plurality of objective lenses matching a gravity center position of the entire lens holder without the plurality of objective lenses.

Abstract: Support device for positioning an optical element includes a first frame unit and a plurality of support units. Each of the support units has a first end for fixedly engaging a part of the first frame unit and a second end for supporting the optical element. The support units are arranged for positioning the optical element along first, second and third directions in a manner of parallel kinematic. The first, second and third directions being translatory directions arranged mutually transverse to each other. There are provided three support units, each of which provides for restriction of first and second degrees of freedom to support the optical element in an isostatic manner, and one of the support units comprises a movable part bearing an entire fraciton of a load to be taken by the one of the support units.

Abstract: An improved lens mount and related lens and lens barrel positioning methods are provided. In one example, a lens mount for use with a miniature camera can include a ring member having a substantially cylindrical interior surface defining a substantially cylindrical interior space. A plurality of elongate ribs are disposed on the interior surface of the ring member and are adapted to exert pressure against an external surface of a lens barrel received by the ring member. In another example, a method of positioning a lens barrel includes inserting a lens barrel into a ring member having a substantially cylindrical interior surface. Pressure can be exerted against an external surface of the lens barrel from a plurality of elongate ribs disposed on the interior surface of the ring member. The pressure can prevent rotation of the lens barrel along at least three axes of rotational freedom.

Abstract: Provided is a lens apparatus for driving an optical member based on a demand signal from a demand device, including: a connector for receiving the demand signal from the demand device by wire; a wireless receiver for wirelessly receiving the demand signal from the demand device; and an identifying section for identifying whether or not the demand device and the lens apparatus have a wired connection with each other, in which the demand signal from the demand device is selected based on a result obtained by the identifying section, and the optical member is driven based on the selected demand signal.

Abstract: A lens barrel of the present invention is of a retractable type. After one frame is retreated from a photographing optical path, another frame moves in an optical axis direction to a position where the one frame has been disposed. The one frame is, for example, a lens frame, and the other frame is, for example, a shutter frame. The present invention can be understood as the invention of a method of switching the lens barrel to a stored state (a retracted state).

Abstract: Disclosed herein is a lens shift mechanism which enables vertical movement of a lens attached to a first member by attaching the first member to a second stationary member so as to be vertically movable with respect to the second member, including: N (an integer of three or more) attachment shafts having a plurality of ball bearings and attached to the first member; and the second member bored with N longitudinal holes located at respective positions corresponding to attachment positions of the N attachment shafts on the first member, each of the N longitudinal holes having a vertical length not shorter than a vertical travel range of the first member.

Abstract: A lens barrel capable of accurately detecting a position of a retractable lens retaining frame. A frame female member for rotating a frame around a lead screw and driving the frame in forward and backward directions along the lead screw is formed with a T-shared protruded member as a detected portion located at a position opposite a rotation-preventing projection. The T-shared member structures a position of the frame together with a transmissive photo-interrupter, to decide a reference position in a retracted state of the frame and for an optical axis entrance completed position of the frame at a time when a transition has changed from a retracted state to a photographable state, and detects a distance from the reference position of the frame or a position of the frame in the photographable state in which a focal distance during wide-angle photographing and telephoto photographing is changed.

Abstract: An optical axis restriction surface, which restricts movement of a first lens frame in an optical axis direction, and a fixing slit, which is located in rear of the optical axis restriction surface, are formed on an end portion of a second lens frame. Lens frame hold portions, which restrict rotation of the first lens frame about an optical axis and movement of the first lens frame in a right-and-left direction, are formed on both sides of the fixing slit. The lens frame hold portions are provided with assembly reference surfaces which restrict movement of the first lens frame in an up-and-down direction. An engaging portion, which is engaged with the fixing slit, and two projection portions, which come in contact with the assembly reference surfaces, are formed on the first lens frame.

Abstract: A laser system comprising a laser assembly for generating a light beam, and collimation assembly movable axially with respect to the laser assembly and being positioned in the optical path of the light beam. The collimation assembly comprises a collimation lens group comprising a first lens component positioned within a first lens mounting cell, a second lens component positioned within a second lens mounting cell and provided with a central portion for receiving and cooperating with the first cell to thereby adjust the axial spacing between the first and second lens components, means for radially adjusting the position of the second cell with respect to the first cell to thereby radially adjust the optical axis of the second lens component with respect to the optical axis of the first lens component, and means formed in the central and flange portions of the second cell for creating flexure therein.

Abstract: A driving device includes a fixed section, a holding member, a driving section disposed at the fixed section and having a driving shaft, a first movable body having a bearing section friction-coupled with the driving shaft, a second movable body formed as a body separate from the first movable body and capable of moving in conjunction with the first movable body although not secured to the first moving body, and support means for supporting the second movable body with the fixed section and the holding member so as to allow the movable body to move in a predetermined plane.

Abstract: In an optical pickup, it is configured such that a first and a second thrust bearings of a motor rotation shaft, a lens holder to be moved in a thrust direction by the motor rotation shaft, and a preload unit which exerts preload of the thrust direction on the lens holder are included, and the second thrust bearing can adjust a position in the thrust direction. In addition, the first and second thrust bearings and the motor rotation shaft are made of conductor, and the optical pickup is manufactured by including the processes of: moving the second thrust bearing in a direction approaching to the motor rotation shaft till electrical continuity between the first thrust bearing and the second thrust bearing is obtained using an electrical continuity checker; subsequently moving the second thrust bearing in a direction departing from the motor rotation shaft; and subsequently fixing the second thrust bearing to the base.

Abstract: In a lens actuator on which a first lens and a second lens are mounted, since the first lens and the second lens are disposed side by side, a problem is involved such that the lens actuator is bulky. The present invention provides a lens actuator comprising a first lens and a second lens having different optical paths, disposed between a light emitting element and an object lens, a holder for holding the first lens and second lens such that the optical axes of the first lens and second lens are parallel to each other, and a driving mechanism for driving the first lens and second lens each in the optical axis directions, wherein the first lens and second lens have respective outer periphery parts respectively outside the effective diameter, and the outer periphery parts of the first lens and the second lens are disposed to be partially overlapped with each other when viewed from the first lens and second lens optical axis direction.

Abstract: An optical pickup actuator including a multi-conductive suspension. The optical pickup actuator may include a base, a holder fixed to the base, a bobbin holding an object lens and having a plurality of driving coils, and a plurality of suspensions connected between the bobbin and the holder and movably supporting the bobbin toward the holder, wherein each of the suspensions may be a multi-conductive suspension including a flexible substrate and a plurality of wires, formed on the flexible substrate, applying currents to the coils.

Abstract: A zoom lens includes a first lens group having a negative refractive power, and second and third lens groups each having a positive refractive power, sequentially aligned from an object side. The first lens group is moved along an optical axis and the second lens group is moved along the optical axis toward the object side, during zooming from a wide-angle end state to a telescopic end state. The third lens group includes a negative sub-lens group having a negative refractive power, and a positive sub-lens group having a positive refractive power, sequentially aligned from the object side. Moving the positive sub-lens group orthogonally to the optical axis causes image shifting. The zoom lens satisfies a conditional expression (1): 0.3<1??<2.5, where ? is a magnification of the positive sub-lens group at the telescopic end state.

Abstract: A mobile communication device includes a main body, a cover body, a first lens module, at least one positioning hole, a second lens module, at least one resilient positioning member and an image sensor. The cover body is slidably mounted on the main body between a first position and a second position. The through hole is defined in the main body and configured for receiving the first lens module. The at least one positioning hole is defined in the first lens module. The second lens module and the image sensor are received in the cover body. The at least one resilient positioning member is defined in the cover body and engaging in the positioning hole at the first position. The image sensor is configured for detecting light from the first and second lens module at the first position and light from the second lens module at the second position.

Abstract: A digital camera module (100) includes a lens barrel (20), a lens holder (22), an image pick-up module (26), and a protective member. The lens barrel defines a central hollow, and has at least one lens (202) received therein. The lens holder defines a central hollow. The lens barrel is movably received in the lens holder along an axis of the lens holder. The image pick-up module is arranged to receive light from the lenses. The protective member is configured for preventing dust and/or particle contamination associated with a relative movement of the lens barrel and the lens holder falling onto the image pick-up module.

Abstract: A driving system for driving an optical element in a first direction. The system includes a linear actuator for producing a displacement in a second direction perpendicular to the first direction, a displacement picking unit being extendable in a third second direction, perpendicular to both of the first and second directions, for picking out a displacement of the linear actuator, and a direction converting unit, disposed at the third-direction second-direction side of the linear actuator, for converting a direction of the displacement picked out by the displacement picking unit into a third direction, perpendicular to both the first and second directions.

Abstract: A lens actuator includes a carrier having a tubular shape having a through-hole provided therein. The through-hole is arranged to mount a lens therein. The lens actuator further includes plural springs contacting upper and lower surfaces of the carrier, a coil fixed to the carrier, a first yoke, a second yoke, and a magnet contacting the first yoke and the second yoke. The coil is placed between the first yoke and the second yoke. This lens actuator moves the lens by a long distance, and has a small size.

Abstract: Objectives, such as projection objectives for semiconductor lithography, are disclosed. An objective generally has an optical axis and optical elements mounted in an objective housing. Projection exposure apparatuses having an objective are also disclosed. In addition, guides and adjusting systems for an optical element in an objective are disclosed. Further, related components and methods are disclosed.

Abstract: An optical recording and/or reproducing apparatus with an optical pickup actuator having high thrust. The optical pickup actuator may include a lens holder which holds an objective lens and is movably supported by a supporting unit, and a magnetic driving unit which drives the lens holder in a focusing direction, a tracking direction, and/or a tilting direction. The magnetic driving unit includes a surface-triple pole magnet portion and a coil portion. The surface-triple pole magnet portion has a plurality of polarized, i.e., differently magnetized, areas formed by facing sides of two magnets among three magnets. The coil portion includes tracking coils and tilt coils disposed to interact with the polarized areas of the surface-triple pole magnet portion and a focusing coil disposed to interact with a non-polarized area of the surface-triple pole magnet portion.

Abstract: An optical subassembly with an optical element, for example a mirror element (7), has an optical surface (9) and bearing points (12) arranged on the circumference. The optical element (7) is connected to a mount (13) at the bearing points (12) via connecting elements (14, 15, 16, 17, 18). Stress-decoupling cutouts, for example curved slots (11), are provided between the optical surface (9) and the bearing points (12).

Abstract: An optical member exchanging mechanism (9) for exchanging optical members (22) includes a body (10) and a sliding assembly (20). The body has an aperture (15) and a guiding rail (12). The sliding assembly is slidably mounted on the guiding rail of the body. The optical members are mounted in the sliding assembly. When the sliding assembly slides relative to the body, the sliding assembly exchanges the optical members to position another optical member adjacent to the aperture.

Abstract: An exemplary optical lens (24) is provided for a camera module (20). The optical lens includes a lens portion (242) and a mounting portion (243). The lens portion is located at a center of the mounting portion. The lens portion is configured for refracting a first portion of image light incident on the lens portion. The mounting portion has a light deflecting part (246). The light deflecting part is formed around the lens portion for deflecting a second portion of image light incident on the mounting portion away from an axis of the lens portion.

Abstract: An apparatus (100) for assembling and testing a lens unit (20) having a barrel (202) and a lens group (204) includes an assembling device (22), a testing device and a mounting member (30). The assembling device is used to assemble the lens group into the barrel to form the lens unit. The testing device is used to test the assembled lens unit. The mounting member is configured for carrying the lens unit in a manner so as to move the lens unit along a circle from a first position where the assembling device performs the assembling to a second position where the testing device performs the testing.

Abstract: A lens barrel has a first group frame provided with a rotating frame having a cam groove and made of a synthetic resin and a cam follower made of a synthetic resin integrated with the circumferential face for relative movement with the rotating frame and engaged with the cam groove, in which a shaft member made of metal is inserted into the center portion of the cam follower. If the lens barrel is dropped and the first group frame undergoes a relatively large impact force, the impact force acts between the cam groove and the cam follower, but since the shaft member is inserted into the cam follower as mentioned above, breakage of a root portion of the cam follower is prevented, and since the cam groove and the cam follower are both resin, plastic deformation on the cam groove side is also prevented.

Abstract: There are provided an optical component module and a camera module capable of preventing damage to the camera module, particularly the optical component module against an impact applied from the outside due to falling, etc. of an apparatus on which the camera module is mounted, even if the strength of the case deteriorates due to miniaturizing, slimming, and weight reducing of the camera module. In the optical component module, a lens that is at least one optical component that is movable in a direction of an optical axis is provided within a case having openings and a primary axis shaft that guides movement of the lens in the direction of the optical axis is provided in the openings. By providing the primary axis shaft, deformation of the case can be suppressed. If an optical pickup device is mounted on the optical component module, a camera module can be formed.

Abstract: A driving apparatus comprises an actuator, the actuator comprising an electromechanical conversion element and a driving shaft attached to the electromechanical conversion element, wherein the driving apparatus expands and contracts the electromechanical conversion element by applying a driving signal to the electromechanical conversion element and reciprocally moves the driving shaft in accordance with expansion and contraction movement of the electromechanical conversion element so as to move a driven member frictionally engaged with the driving shaft, and wherein the driving signal is a pulse signal, and a time period corresponding to a half wavelength of a damping vibration displacement of a lowest resonance frequency in the actuator is set as a shorter output time among a high output time period and a low output time period of the driving signal.

Abstract: A driving apparatus comprises an actuator, the actuator comprising an electromechanical conversion element and a driving shaft attached to the electromechanical conversion element, wherein the driving apparatus expands and contracts the electromechanical conversion element by applying a driving signal to the electromechanical conversion element and reciprocally moves the driving shaft in accordance with expansion and contraction movement of the electromechanical conversion element so as to move a driven member frictionally engaged with the driving shaft, and wherein the driving signal is a pulse signal, and half of a time period corresponding to a reciprocal of a lowest resonance frequency in the actuator is set as a shorter output time among a high output time period and a low output time period of the drive signal.

Abstract: A portable magnification stand includes a lower inner plane area surrounded by and held in place by a lower coplanar support material. A back pair of adjustable arms and a front pair of adjustable arms are mounted to the lower planar base unit and an upper planar lens unit that holds a lens for magnifying objects. The back pair of adjustable arms are longer than the front pair of adjustable arms causing the magnification of objects to appear greater near the front portion of the upper planar lens unit compared with objects near the near the back portion of the upper planar lens unit. Swingable extensions shaped as trapezoidal planar materials can be used in lieu of the adjustable arms to provide the appropriate magnification in a more compact and lighter weight design.

Abstract: In an objective lens driving device having a lens holder movably holding an objective lens, a damper base, and a suspension member elastically supporting the lens holder with respect to the damper base, the suspension member consists of four suspension wires disposed on both sides of the damper base and the lens holder. The damper base has first supporting portions for supporting one end of each suspension wire while the lens holder has second supporting portions for supporting another end of each suspension wire. The second supporting portions are apart from the first supporting portion by a first distance. The damper base has damper portions which are disposed between the first and the second supporting portions and which are apart from the first supporting portions by a second distance. The second distance is laid in a range between one-fifths and two-fifths of the first distance.

Abstract: A system and method for laser source detection. An exemplary embodiment of the system includes a first array of lenses, a second array of opto devices (including light sources and light detectors), and at least one processor. By positioning the array of lenses to determine the lens position at which energy from an incoming laser is greatest on the light detectors, the approximate location of the laser source may be determined. Upon determining the source, responsive action may be taken. If the incoming laser is from a friendly party, a friendly-party notification may be provided. If the incoming laser is from an enemy, reciprocal targeting or false reflections may be employed.

Abstract: A stage apparatus in which a movable stage is guided in first and second directions orthogonal to each other on a stationary member, includes a pair of first elongated holes formed on one of the movable stage and the stationary member and are elongated in the first direction; a pair of link members having two engaging pins at first ends thereof which are engaged in the pair of first elongated holes to be movable therein, respectively, one of second ends of the pair of link members being pivoted at the other of the movable stage and the stationary member, and the other of the second ends of the pair of link members being supported by the other of the movable stage and the stationary member; and a link-member support mechanism for moving the movable stage in the second direction while maintaining a symmetrical shape thereof.

Abstract: An optical element including a first groove extending from first end of the outer peripheral face in an optical axis direction towards second end, and a second groove connected to the first groove and extending from second end of the outer peripheral face in the optical axis direction towards first end; and a position-adjusting concave part which is between the first and second grooves and adjusts positions by adjusting member in the optical axis direction, a revolving direction about the optical axis, a width direction of first and second grooves, which is orthogonal to the optical axis, and in a synthesized direction that is a combination of at least two of those directions, wherein the optical element is molded by using only a first molding die for molding a part on the first groove side and a second molding die for molding a part on the second groove side.

Abstract: A holding apparatus provided with a holding portion for holding a flange portion of an optical element. The holding portion includes a bearing surface block having a bearing surface, which contacts the flange portion, and a bearing surface block support mechanism, which rotatably supports the bearing surface block about a tangential axis of the optical element. This structure holds the optical element with the optical element holding apparatus in a kinematical manner and maintains satisfactory imaging performance in the optical element.

Abstract: An optical-element driving mechanism is configured to drive an optical element, and includes a uniaxial driving mechanism that includes a linear actuator that drives in a first direction, and a link mechanism that converts a displacement in a direction orthogonal to the first direction. The linear actuator is level with the link mechanism in an optical-axis direction. The uniaxial driving mechanism is arranged in order of the link mechanism and the linear actuator in a radial direction when viewed form an optical axis of the optical element.

Abstract: A microscope lens barrel includes an input port where observation light enters the microscope lens barrel; a plurality of output ports which the observation light goes out of the microscope lens barrel; an optical-path switching mechanism which selectively switches an optical path of the observation light to guide the observation light from the input port to at least one of the output ports; and a supporting part which supports the optical-path switching mechanism. The input port, the output ports, and the supporting part are integrally formed as a tubular body frame so that the input port, the output ports, and the supporting part are arranged at respective center positions of sidewalls of the tubular body frame.

Abstract: A lens holder for holding a plurality of lenses is provided. The lens holder is assembled from a plurality of subunits divided on a plane that is parallel to an optical axis. A subunit includes a substantially cylindrical outer shell and front side rear side portions that extend from an inner surface of the outer shell toward the optical axis to support at least one lens from in front and behind respectively. When the at least one lens is attached between the portions, one of the portions is harder to deform than the other of portions.

Abstract: An electro-optical device includes an electro-optical panel including a substrate and a plurality of electro-optical elements arranged on the substrate, a converging lens that converges a light beam emitted from the electro-optical panel, and a light-transmitting member interposed between the electro-optical panel and the converging lens. A first surface of the light-transmitting member opposing the converging lens is rotated about an axis along which the electro-optical elements are arranged on the substrate.

Abstract: A lens barrel including a telescopic cylinder accommodated within a fixed cylinder, and lenses retained in the telescopic cylinder. The lens barrel includes lens retaining frames to retain at least one of the lenses and a lens driving device to drive the lens retaining frames so as to drive the lenses along a longitudinal axis of the telescopic cylinder between a collapsed position in which one portion of the lenses is stored in the fixed cylinder and an extended position in which one portion of the lenses is extended out of the fixed cylinder toward a photographing subject. The lens barrel further includes a retractable lens that is retracted into the fixed cylinder through an opening in a wall of the fixed cylinder when the telescopic cylinder is in the extended position, and a retractable tens retaining frame to retain the retractable lens.

Abstract: The generatrix directions of cylindrical lenses 11a and 11b are perpendicular to the optical axis, and are perpendicular to each other. As a result, the optical system combining the cylindrical lenses 11a and 11b can achieve the same optical effect as a spherical lens. This system is characterized by the fact that since the respective lenses are cylindrical lenses, there is no shift in the optical axis even if the lenses are moved in the generatrix direction. For example, in cases where scratches on the lenses have become conspicuous, the useful life of the laser device can be extended by moving the lenses in the generatrix direction (direction indicated by the arrow) by means of a moving mechanism (not shown in the figures), e.g., a stage equipped with a micrometer, and using unused portions of the lenses.

Abstract: A lens barrel including a telescopic cylinder configured to be accommodated within a fixed frame; a plurality of lens groups configured to be retained in the telescopic cylinder; a lens driving device configured to drive the plurality of lens groups along a longitudinal axis of the telescopic cylinder between a collapsed position in which at least one portion of the plurality of lens groups is stored in the fixed frame and an extended position in which the at least one portion of the plurality of lens groups is extended out of the fixed frame; and a retractable lens group configured to be retracted into the fixed frame through an opening in a wall of the fixed frame when the telescopic cylinder is in the extended position.

Abstract: A zoom lens wherein the image plane movement upon lens shifting is minimized. A power variation section and a final lens group are disposed in order from an object side. The power variation section includes at least two lens groups movable in an optical axis direction to vary a lens position state. The final lens group is fixed in the optical axis direction and includes first to third sub groups having negative, positive and positive refracting powers and disposed in order from the object side. The second sub group is shiftable substantially perpendicularly to the optical axis to shift an image. A conditional expression 0.2<ft/fBt<0.8 is satisfied where ft and fBt are the focal distances of the lens system and entire lens groups disposed on the object side of the third sub group in the telephoto end state.

Abstract: An optical device. A lens module is movably disposed in a lens housing. A drive mechanism is connected to the lens module, driving the lens module along an optical axis of the lens module. A brake mechanism is disposed between the lens housing and the lens module and moves perpendicular to the optical axis, fixing and releasing the lens module. When the brake mechanism releases the lens module, the lens module moves along the optical axis.

Abstract: The plano-convex lens of a projection headlight has a holding edge (4) integrally formed on an outer lens edge and a supporting edge (5) projecting from its plane surface (3) and formed integrally with the holding edge (4). The supporting edge (5) and the holding edge (4) form a continuous cylindrical outer circumferential surface (45) extending over their outer sides. The convex surface (2) and the plane surface (3) of the lens are bright pressed surfaces so that the grinding and polishing steps usually used in making the lens can be eliminated. The method of manufacturing the lens including bright pressing the convex and plane surfaces is also part of the invention.

Abstract: A low-deformation mounting device of a rotationally asymmetric optical element, particularly an optical element in a projection lens used in semiconductor lithography. Said optical element is mounted in a frame and is provided with at least three connection surfaces that are positioned perpendicular to each other. Frame-connecting members are disposed in such a way that at least one but no more than two degrees of translational freedom and at least one but no more than two degrees of rotational freedom are obtained by means of said connecting members.

Abstract: To overcoming any inconvenience in an optical unit, caused by a protrusion (burr) formed on a plastic lens when the plastic lens is molded, an optical unit is provided and has an injection molded plastic lens and a lens barrel. The injection molded plastic lens is fitted in a lens housing groove of the lens barrel so that a protrusion on one side of a flange of the injection molded plastic lens is located outside the lens housing groove.

Abstract: A projector includes a light source; an optical modulator; a projection lens, which has a lens barrel containing plural lenses, for projecting the optical image; as well as a structure showing a substantially L-shaped lateral contour and including an inner horizontal section, to which the optical modulator is attached, and an outer vertical section, to which the projection lens is attached; and a lens shifting mechanism for shifting the projection lens along the outer vertical section. The lens barrel has a flange projecting to the outside of the lens barrel at the base end side of the projection direction so that the lens barrel is fitted to the outer vertical section. The outer vertical section has a lens contacting surface projected and curved in accordance with curvature amount of the image forming surface on the base end side of the projection lens so as to contact the flange.