JP2009300761A - Imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging apparatus capable of improving assembling property and reducing yield by easily making fine adjustment of a set field angle even with dispersion in the machining tolerance of parts and in the clearance of a moving lens frame fitted to a lens frame without enlarging the imaging apparatus capable of adjusting a focal distance. <P>SOLUTION: The imaging apparatus 30 configured to adjust optical characteristics by moving partial lenses out of objective lenses forward and backward by an actuator 62 includes a fixed lens frame 36 holding the objective lenses excluding the moving partial lenses; a moving lens frame 32 holding the partial lenses inside the fixed lens frame to move forward and backward along a photographing optical axis and formed with moving position regulation faces 40a, 40b at the front and rear parts in the moving direction; and an adjusting member 37 provided at the fixed lens frame and abutting on the moving position regulation faces to regulate the movement of the moving lens frame and to make fine adjustment of the regulating position of the forward/backward movement of the moving lens frame. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an imaging apparatus that varies optical characteristics disposed in an endoscope.

As is well known, an electronic endoscope is widely used for observation, treatment, etc. of a living body (inside a body cavity) or inspection, repair, etc. in an industrial plant facility. In recent years, an imaging apparatus that can change the focal length by moving the observation optical system in the direction of the photographic optical axis for a focusing function for adjusting the focus of a photographic image or a zooming function for performing wide zooming / tele zooming. Is used.
For example, Patent Literature 1, Patent Literature 2, and Patent Literature 3 disclose techniques for changing the optical characteristics by moving the lens frame for the zooming function of the imaging apparatus.

  First, Patent Document 1 discloses a technique of an imaging apparatus used in an endoscope apparatus in which a lens frame that changes a focal length is moved by an actuator unit that is a rapid deformation voltage actuator. Further, in this imaging apparatus, one end of a coil spring formed of a shape memory alloy wire is fixed to a protrusion formed integrally with a lens frame to which a lens is attached, and connected to the coil spring. A technique for moving a lens frame that changes the focal length by energizing or de-energizing through a lead wire is also disclosed.

  Further, Patent Document 2 discloses a technique of a lens adjustment frame device that changes a focal length by rotating a cam cylinder around an optical axis. In this conventional lens adjustment frame device, the inner link can be translated along the optical axis by an adjustment screw for adjusting the lens position with respect to the frame portion.

Patent Document 3 discloses a technique in which a stroke end regulating mechanism that positions a stroke end on the subject side is provided on a drive shaft connected to an arm portion extended to a movable lens frame.
JP-A-5-341209 JP 2000-275489 A JP 2000-206423 A

  By the way, in recent years, a conventional imaging apparatus capable of changing the focal length because of a zooming function used in an endoscope apparatus has a large maximum viewing angle (hereinafter referred to as an angle of view) so that a wide range can be observed. Wide-angle optical characteristics are required. Specifically, for example, an imaging device of a general conventional endoscope apparatus has an optical characteristic that can be changed to, for example, a field angle of 140 ° at the maximum. In recent years, imaging devices having a wide-angle optical characteristic that can change the angle of view to a maximum of 170 ° have also appeared.

  In these imaging devices having different maximum angles of view, for example, when the same tolerance of the angle of view is required for both ± α °, the standard for setting 140 ° ± α ° and 170 ° ± α ° is 140 ° ° ± β ° and 170 ° ± γ ° (γ = 140 ° / 170 ° × β), and the variation in the angle of view required by the imaging device having the maximum angle of view of 170 ° becomes severe. In addition, there is a problem that the field rays are more easily emitted as the angle of view becomes larger than 170 °.

  Further, in the imaging apparatus, for example, when each objective lens group in each lens unit including a moving lens in which optical characteristics with a maximum field angle of 140 ° and a maximum angle of 170 ° are set has the same optical path deflection angle The lens unit in which the field angle of 170 ° at the maximum is set is more deteriorated in the peripheral image due to an error in optical characteristics than the lens unit in which the field angle of 140 ° is set at the maximum.

  In other words, among the two imaging devices having the same deviation of the optical axis center due to the optical path deflection angle of the objective lens group, the imaging device having a lens unit with a large maximum angle of view has a larger deviation of the maximum angle of view, and the target It is difficult to adjust to the standard value.

  As described above, the imaging apparatus is required to have a mounting accuracy of the moving lens of the lens unit with a large angle of view that can be varied to the maximum. In other words, the imaging device has a larger optical path declination of the objective lens group due to processing tolerances of parts during assembly and variations in the clearance of the moving lens frame fitted to the lens frame. Deterioration will increase.

  In particular, the above-described imaging device disclosed in Patent Document 1 is difficult to adjust the processing tolerance of parts during assembly and the variation in the clearance of the moving lens frame fitted to the lens frame. However, there has been a problem that the deviation of the maximum angle of view becomes large, it becomes difficult to adjust to the target standard value, and the yield is reduced.

  Further, the technology of the lens adjustment frame device disclosed in Patent Document 2 is mainly incorporated in a cam frame mechanism used in a camera barrel, and is incorporated in a small imaging device used in an endoscope apparatus. In addition, there is a problem that if the cam frame mechanism and the lens adjustment frame device are provided, the imaging device becomes large.

  Furthermore, the image pickup apparatus disclosed in Patent Document 3 must be provided with two stages of screw mechanisms for screwing the arm part and the stopper ring on the drive shaft connected to the arm part. There was a problem that it would become. Moreover, since it is set as the structure covered with a protective cover after adjustment, it cannot adjust directly from the outside at the time of repair. Furthermore, although a wire-type mechanism is disclosed, there is a problem that a mechanism that adjusts a drive shaft and an arm portion with a screw mechanism cannot be adjusted while confirming an image.

  Therefore, in view of the above circumstances, the present invention aims at an imaging apparatus capable of changing the focal length, and without moving the component up to a large size, without moving the lens frame, and a moving lens frame that fits into the lens frame. Even if there is a variation in the clearance, it is possible to easily make fine adjustments to the set angle of view, thereby improving the assembly performance, improving the yield, and improving the repairability. is there.

  In order to achieve the above object, an imaging apparatus according to the present invention is an imaging apparatus in which a part of an objective lens is moved forward and backward by an actuator to change optical characteristics. A fixed lens frame to be held, and inside the fixed lens frame, the part of the lens is held, and the actuator is moved forward and backward along the photographing optical axis to form a moving position regulating surface in the front and rear of the moving direction. The movable lens frame is provided on the fixed lens frame and is in contact with the movement position regulating surface to regulate the movement of the movable lens frame and to finely adjust the regulation position where the movable lens frame moves forward and backward. And an adjusting member.

  According to the present invention, in an imaging device capable of changing the focal length, even if there is a variation in processing tolerance of parts during assembly and clearance with a moving lens frame that fits into the lens frame, without increasing the size. Thus, it is possible to easily realize fine adjustment to the set angle of view, thereby improving the assembling property, improving the yield, and improving the repairability.

  The present invention will be described below with reference to embodiments based on the drawings.

(First embodiment)
First, the present invention will be described with reference to FIGS. 1 to 6 relate to the first embodiment of the present invention, FIG. 1 is a configuration diagram showing the entire electronic endoscope system, and FIG. 2 is an internal configuration of the distal end portion of the endoscope. 3 is a cross-sectional view showing the configuration of the imaging apparatus, FIG. 3 is a cross-sectional view showing a state where the moving lens frame is moved forward, and FIG. 4 is a cross-sectional view of the imaging apparatus showing a state where the position of the moving lens frame is moved backward from 5 is a partially enlarged cross-sectional view of the imaging apparatus showing a state in which the position of the moving lens frame corresponding to FIG. 3 has moved rearward. FIG. 6 is a diagram illustrating the position of the moving lens frame corresponding to FIG. It is sectional drawing to which the imaging device which showed the state which moved is expanded partially.

  As shown in FIG. 1, an electronic endoscope system (hereinafter simply referred to as an endoscope system) 1 according to the present embodiment includes an electronic endoscope device (hereinafter simply referred to as an endoscope) 2, and a light source device. 3, the video processor 4, and the color monitor 5 are electrically connected.

  The endoscope 2 includes an insertion portion 9 and an operation portion 10 in which the insertion portion 9 is extended. A universal cord 17 extending from the operation portion 10 is connected to the light source device 3 via a scope connector 18. Connected with. A coiled scope cable 19 is extended from the scope connector 18. An electric connector portion 20 is provided at the other end of the scope cable 19, and the electric connector portion 20 is connected to the video processor 4.

  The insertion portion 9 includes a distal end portion 6, a bending portion 7, and a flexible tube portion 8 that are connected in order from the distal end. A distal end opening, an observation window, a plurality of illumination windows, an observation window cleaning port, and an observation object cleaning port (not shown) are disposed on the distal end surface of the distal end portion 6.

  On the back side of the observation window, an imaging device (described later) built in the distal end portion 6 is disposed. Further, on the back side of the plurality of illumination windows, a light guide bundle (not shown) that transmits illumination light from the light source device 3 and is inserted from the distal end portion 6 into the universal cord 17 is provided.

  The observation window cleaning port and the observation object cleaning port constitute openings of two cleaning tubes (not shown) that are inserted from the distal end portion 6 into the universal cord 17. These cleaning tubes are connected to a cleaning tank (not shown) in which cleaning water is stored, a compressor, and the light source device 3 side.

  The operation unit 10 includes an anti-bending portion 11 from which the insertion portion 9 extends, a forceps port 12 disposed on a side portion on the lower side, an operation portion main body 13 that constitutes a grip portion in the middle portion, and an upper side. A bending operation unit 16 including two bending operation knobs 14 and 15 provided, an air / water supply control unit 21, a suction control unit 22, and a switch unit 23 mainly operating an imaging function, which includes a plurality of switches. And is composed of. The forceps port 12 of the operation unit 10 constitutes an opening of a treatment instrument channel (not shown) that is mainly inserted into the insertion portion 9 up to the distal end opening of the distal end portion 6.

Next, the configuration of the distal end portion 6 of the endoscope 2 will be mainly described below with reference to FIGS.
As shown in FIG. 2, the distal end portion 6 has an imaging device 30 disposed therein. The imaging device 30 is inserted and disposed in a hard tip rigid member 24 and is fixed to the tip rigid member 24 by a set screw 27 from the side surface direction. Further, a watertight O-ring 28 is disposed on the outer peripheral portion on the distal end side of the imaging device 30. A tip cover 25 constituting the tip surface of the tip portion 6 is bonded and fixed so as to cover the tip of the tip rigid member 24.
Note that the distal end opening, which is a hole formed in the distal end cover 25, constitutes the opening of the treatment instrument channel 12b in the distal end 6 as described above. Further, a distal end insertion portion rubber member 12 a that integrally covers the outer periphery of the distal end rigid member 24 and the bending piece 26 in the bending portion 7 is provided so as to form the outer shapes of the distal end portion 6 and the bending portion 7. . The distal end outer peripheral portion of the distal end insertion portion rubber member 12 a is fixed to the distal end portion 6 by a pincushion bonding portion 29.

  In addition, about members, such as a washing tube arrange | positioned at the front-end | tip part 6, the light guide bundle for illumination, since they are conventionally well-known structures, those description is abbreviate | omitted.

Next, the configuration of the imaging device 30 shown in FIGS. 3 to 6 will be described in detail below.
The imaging device 30 according to the present embodiment has a configuration in which an internal lens moves forward and backward because of a focusing function or a zooming function that changes optical characteristics by changing a focal length. In the present embodiment, the configuration in which the internal lens that changes the optical characteristics by changing the focal length is moved forward and backward will be described as a zooming function for switching between wide and tele.

  An imaging apparatus 30 shown in FIGS. 3 to 6 includes a front group lens frame 34 that is a fixed lens frame that constitutes a front group lens unit 31 and holds a front group lens 35 including a plurality of objective lenses from the tip. A rear lens group frame 36 that is a fixed lens frame that holds a rear lens group 33 composed of a plurality of objective lenses, and a moving lens 39 that is provided between the lens groups 35 and 33 and constitutes the moving lens unit 32. The movable lens frame 38 that is held and the solid-state image sensor unit 46 having a CCD, a CMOS, and the like are mainly configured.

  The rear end portion of the front group lens frame 34 and the front end portion of the rear group lens frame 36 are fitted and joined. Further, the front end portion of the solid-state image sensor holding frame 41 that holds the solid-state image sensor unit 46 is inserted and fixed to the rear end portion of the rear group lens frame 36.

  The moving lens unit 32 is slidably disposed along the photographing optical axis O direction in the rear group lens frame 36 on the rear side of the front group lens unit 31. Although not shown, a connecting rod 40 having a substantially cross-sectional shape in the longitudinal direction is provided below the moving lens frame 38 of the moving lens unit 32 so as to extend downward. Further, the connecting rod 40 constitutes a part of the moving lens unit 32.

  The solid-state image sensor unit 46 includes two optical members 42 and 43, a solid-state image sensor chip 45 with an image area 44 positioned on the front surface, and a multilayer substrate 47 in the solid-state image sensor holding frame 41 in order from the front end. Have. The solid-state image sensor chip 45 and the multilayer substrate 47 are electrically connected by FPC.

  In addition, the multilayer substrate 47 is connected to a plurality of communication lines of the cable 51. The cable 51 is inserted and arranged inside the endoscope 2, and is electrically connected by the video processor 4 and the electrical connector unit 20 via the universal cord 17 and the scope cable 19. Further, a substantially cylindrical cable holding member 50 is externally attached to the tip portion of the cable 51.

  A reinforcing frame 48 is fitted on the outer peripheral portion of the base end of the solid-state image sensor holding frame 41, and a heat shrinkable tube that integrally covers the cable holding member 50 on the outer periphery of the reinforcing frame 48 up to the distal end portion of the cable 51. A certain covering member 49 is provided. In addition, in the space formed by the reinforcing frame 48 and the covering member 49 from the base end portion of the solid-state image sensor holding frame 41 provided with the solid-state image sensor chip 45 to the cable holding member 50, an adhesive or the like is used. Filled with protective agent.

  In addition, an actuator holding portion 52 that holds an actuator 62 that constitutes an actuator device that moves the moving lens unit 32 forward and backward is formed in the rear lower portion of the rear group lens frame 36 so as to protrude downward.

Next, the configuration of the actuator 62 attached to the imaging device 30 will be described.
The actuator 62 includes a long guide tube 53 formed of an insulating member formed of a hard non-metal that is inserted into the actuator holding portion 52 of the rear group lens frame 36, and is movable forward and backward within the guide tube 53. A movable shaft body 54 that is a rod-like hard member inserted through the movable shaft body 54, an insulating member 55 having the same outer diameter as that of the movable shaft body 54 connected to the base end of the movable shaft body 54, and a distal end portion connected to the insulating member 55 The shape memory alloy wire 56 inserted into the guide tube 53, the pressing spring 57 constituting the elastic body as an urging member to be externally inserted into the shape memory alloy wire 56, and the shape memory alloy wire 56 are inserted therethrough. A spring stopper tube 58 made of an insulating tube inserted into the rear portion of the tube 53 and a block body 59 for caulking and fixing the base end of the shape memory alloy wire 56 are provided.

  The shape memory alloy wire 56 is a wire having a diameter of several tens of microns, made of a shape memory alloy (hereinafter referred to as “SMA”) that contracts when heated and expands when cooled. (Hereinafter, the shape memory alloy wire is abbreviated as SMA wire).

  The guide tube 53 described above is arranged with its tip position aligned with the tip surface of the actuator holding portion 52, and is adhesively fixed to the actuator holding portion 52. The guide tube 53 has a length that extends to the rear end portion of the imaging device 30. The guide tube 53 is precisely fixed so that the longitudinal axis thereof is parallel to the photographing optical axis O so that the optical characteristics set by the imaging device 30 are satisfied.

  Further, the moving shaft body 54 provided so as to be movable forward and backward in the guide tube 53 is screwed to the connecting rod 40 at the tip. The moving shaft 54 has a length shorter than that of the guide tube 53, and a base end portion is located in the guide tube 53. The moving shaft 54 is also precisely set so as to be parallel to the photographing optical axis O so that the advancing / retreating moving axis that advances and retreats in the guide tube 53 satisfies the optical characteristics of the imaging device 30.

  The SMA wire 56 inserted into the guide tube 53 is folded back by an insulating member 55 connected to the proximal end of the moving shaft body 54. The SMA wire 56 is folded and one end thereof is fixed by crimping to the block body 59, and the other end is fixed by crimping to another block body (not shown). The folded-back SMA wire 56 is covered with an insulating tube (not shown).

  A pressing spring 57 extrapolated to the SMA wire 56 is disposed in the guide tube 53 between the insulating member 55 and the spring stopper tube 58 so that both ends thereof are in contact with each other. Since the spring stop tube 58 is fixed to the guide tube 53, the pressing spring 57 urges the insulating member 55 that moves forward and backward integrally with the moving shaft 54 forward.

  The block body 59 that fixes both ends of the SMA wire 56 has a shape larger than the hole diameter of the spring stopper tube 58 and is disposed in contact with the rear end surface of the spring stopper tube 58. The block body 59 is electrically connected to the wire 60a of the cable 60 on the application side of the electric cable 61 by soldering or the like. The other block body (not shown) is electrically connected to the strand 60a of the cable 60 on the return side by soldering or the like.

The connecting portion between the block body 59 and the electric cable 61 is covered with an insulating tube 63 that integrally covers the proximal end portion of the guide tube 53, so that insulation is maintained. The electric cable 61 is disposed up to the scope connector 18 of the universal cord 17 of the endoscope 2, and the power applied to the electric cable 61 is supplied from the video processor 4 via the scope cable 19.
The rear lens group frame 36 is formed with a notch 36a that forms a guide groove so that the connecting rod 40 connected to the movable lens unit 32 can move straight forward and lower.

  As shown in FIGS. 5 and 6, the connecting rod 40 that is guided straight by the notch 36 a extends from the moving lens unit 32 and is below the connecting position with the moving shaft body 54. Inclined surfaces 40a and 40b, which are movement position restricting surfaces that are notched in a plane with a predetermined angle with respect to an axis orthogonal to the photographing optical axis O, are formed before and after the end portion (lower end portion). ing. That is, the inclined surfaces 40a and 40b constitute a position adjusting surface having a predetermined angle with respect to an axis orthogonal to the photographing optical axis O.

  Further, the rear lens group frame 36 has two screw hole portions 36b formed on the side facing the end portion of the connecting rod 40 on which the inclined surfaces 40a and 40b are formed at a position separated by a predetermined distance. An adjustment screw 37 as an adjustment member is screwed into each of the screw hole portions 36b.

The adjustment screw 37 screwed into the screw hole portion 36b has a conical surface 37a which is a conical position adjusting portion at the end opposite to the screw head. This conical surface 37a has a predetermined inclination angle of two inclined surfaces 40a and 40b of the connecting rod 40 in the triangular shape of the cross section divided into two in the vertical direction so as to pass through the vertex. It matches the tilt angle.
Further, the adjustment screw 37 is screwed into the screw hole 36 b so that the conical surface 37 a protrudes from the inner surface of the rear group lens frame 36.

  Note that the distance between the centers of the two screw hole portions 36b formed in the rear lens group frame 36 is set so as to substantially match the distance that the movable lens unit 32 moves back and forth, as will be described later. .

Next, the operation of moving the moving lens unit 32 forward and backward by the actuator 62 of the imaging apparatus 30 of the present embodiment configured as described above will be described in detail below.
When driving the actuator 62 of the imaging device 30 for telezooming on the subject by the endoscope 2, the power supply that constitutes the video processor 4 is based on a predetermined operation by the operation unit 10 of the endoscope 2. A current flows through the electric cable 61. Then, the current flows through the electric cable 61 and the SMA wire 56, and the SMA wire 56 generates heat and contracts from the length t in FIG. 3 to the length w in FIG.

  Then, the moving shaft body 54 resists the urging force of the pressing spring 57 by the SMA wire 56 together with the insulating member 55 from the state shown in FIG. 3 to the state shown in FIG. 4 (the state shown in FIGS. 6 to 5). It is pulled backward (in the direction of arrow b in FIGS. 4 and 5). As a result, the connecting rod 40 fixed to the distal end of the moving shaft body 54 is moved backward (in the direction of arrow B in FIGS. 4 and 5) while being guided along the moving lens unit 32 by the notch 36 a of the rear lens group frame 36. Go to).

  That is, the moving lens unit 32 moves from the state positioned on the front side in FIG. 3 (FIG. 6) to the state positioned on the rear side in FIG. 4 (FIG. 5) due to the contraction action due to heat generation of the SMA wire 56. At this time, the moving shaft 54 is moved by the guide tube 53 to the photographing optical axis O that moves the moving lens unit 32 to the tele end position, which is the predetermined viewing angle T set in the imaging device 30, as shown in FIG. Parallel straight guides are made. The connecting rod 40 is restricted from moving rearward by the conical surface 37a of the adjusting screw 37 coming into contact with the inclined surface 40b on the rear side.

  On the other hand, when the endoscope 2 drives the actuator 62 of the imaging device 30 for wide zooming on the subject, the video processor 4 is configured based on a predetermined operation by the operation unit 10 of the endoscope 2. The current of the electric cable 61 is stopped from the power source. Then, the heat generation of the SMA wire 56 is stopped, and the SMA wire 56 expands (returns to the original state) from the length w in FIG. 4 to the length t in FIG.

  That is, when the current is stopped from flowing through the electric cable 61, the SMA wire 56 is naturally cooled and returns to its original length (length t shown in FIG. 3). At this time, the insulating member 55 is pushed forward and moved by the urging force of the pressing spring 57. In accordance with this, the moving shaft body 54 and the connecting rod 40 that have moved in the proximal direction are guided forward by the notch portion 36a of the rear lens group frame 36 (in the direction of arrow f in FIGS. 3 and 6). ). Then, the moving lens unit 32 moves in a forward direction (in the direction of arrow F in FIGS. 3 and 6).

  At this time, the connecting rod 40 is restricted from moving forward by the conical surface 37a of the adjusting screw 37 coming into contact with the inclined surface 40a on the front side.

  As described above, the actuator 62 that moves the moving lens unit 32 forward and backward is configured to advance and retract the moving shaft body 54 by the thermal contraction of the SMA wire 56 and the urging force of the pressing spring 57.

  As described above, the imaging device 30 according to the present embodiment forms the inclined surfaces 40a and 40b around the lower end of the connecting rod 40 interposed between the moving lens unit 32 and the actuator 62, and these inclined surfaces. By providing the rear group lens frame 36 with an adjusting screw 37 having a conical surface 37a that comes into contact with 40a and 40b, the front and rear movement of the movable lens unit 32 during telezooming and wide zooming can be restricted. .

  In other words, the imaging device 30 adjusts the adjusting screw 37 to the rear lens group frame 36 in accordance with the positions at which the front and rear surfaces of the connecting rod 40 that moves the moving lens unit 32 back and forth in conjunction with the driving of the actuator 62 are moved. And the inclined surfaces 40a, 40b are in contact with the conical surface 37a to restrict the movement of the movable lens unit 32 in the front-rear direction.

  With such a configuration, the imaging device 30 adjusts the screwing amount of the adjustment screw 37 to the screw hole portion 36b of the rear group lens frame 36 during assembly or maintenance, so that the rear group lens frame 36 is adjusted. By finely adjusting the amount of protrusion of the conical surface 37a from the inner surface of the lens, adjustment for restricting the movement of the moving lens unit 32 within the error range of the optical characteristics at a predetermined viewing angle can be easily performed.

  That is, the imaging device 30 has a predetermined field of view in which the position of the wide zooming end is defined and the moving lens unit 32 moves rearward so that the moving lens unit 32 moves forward and falls within the standard of a predetermined viewing angle W. The telescoping end position is regulated so as to be within the standard of the angle T by adjusting the screwing amount of the adjusting screw 37 to the screw hole portion 36b of the rear group lens frame 36, and the cone from the inner surface of the rear group lens frame 36. This can be easily performed by finely adjusting the protrusion amount of the surface 37a.

  From the above description, the imaging device 30 of the present embodiment can detect the position of the wide zooming end of the moving lens unit 32, even if the accuracy of assembling the moving lens unit 32 to the rear lens group frame 36 is slightly poor, and The position of the telezooming end can be easily finely adjusted with the adjusting screw 37. In particular, as the maximum angle of view of the image pickup device 30 increases, a defect occurs in the optical path deflection angle of the objective lens group due to the processing tolerance of parts during assembly and the variation in the clearance of the moving lens frame fitted to the lens frame. However, even when the wide viewing angle W is set to a wide angle of, for example, 170 ° at the maximum, the position of the wide zooming end where the movable lens unit 32 moves forward and stops is fine so that it falls within the error range of the optical characteristics. By adjusting, the problem of the angle of view due to the optical path declination of the objective lens group can be solved. In addition, the imaging device 30 is configured to finely adjust the specified position where the movable lens unit 32 moves with the adjustment screw 37, and therefore does not increase in size as compared with the conventional configuration.

  Further, since the adjustment screw 37 is screwed into the rear lens group frame 36, fine adjustment is possible while checking the image, and it is possible to repair the image pickup apparatus 30 without disassembling at the time of repair. It becomes.

  From the above, the imaging device 30 having a zooming function and capable of varying the focal length in the present embodiment is free from the processing tolerance of parts and the clearance of the moving lens frame fitted to the lens frame without increasing the size. Even if there are variations, the fine adjustment to the set angle of view can be easily performed, so that the assembly is improved, the yield is improved, and the repairability is also improved.

(Second Embodiment)
Next, a second embodiment of the present invention will be described below based on FIG.
FIG. 7 is a partially enlarged cross-sectional view of the imaging apparatus showing a state in which the position of the moving lens frame has moved forward according to the second embodiment of the present invention. In the following description, the same reference numerals are used for the same configurations as those of the imaging device 30 of the first embodiment described above, and detailed descriptions of these configurations are omitted.

  As shown in FIG. 7, the image pickup apparatus 30 according to the present embodiment has a contact that finely adjusts so that the position of the wide zooming end where the moving lens unit 32 moves forward and stops falls within the error range of the optical characteristics. The member 64 is provided in the rear lens group frame 36.

  Specifically, the rear lens group frame 36 has a through hole 65 formed in the lower part on the front side, and a screw hole 36 b formed directly below the through hole 65. The adjustment screw 37 described above is screwed into the screw hole 36b.

  In the through hole 65, an abutting member 64, which is an adjusting member here, is disposed so as to be in contact with the inclined surface 40a on the front side of the connecting rod 40 and restrict the forward movement of the connecting rod 40. The agent 65a is injected, and the adjustment screw 37 and the contact member 64 are fixed.

  The abutting member 64 has an inclined surface 64a that is cut out so that the front surface matches a predetermined angle of one side of the conical surface 37a, and a rear surface that matches a predetermined inclined angle of the inclined surface 40a of the connecting rod 40. And an inclined surface 64b cut out. That is, the abutting member 64 is configured such that the inclined surface 64a on the front side abuts on the conical surface 37a of the adjusting screw 37, and the inclined surface 64b on the rear side comes into surface contact with the inclined surface 40a on the front side of the connecting rod 40. It is configured.

  In addition, the imaging device 30 defines the position of the wide zooming end in the screw hole on the front side of the rear lens group frame 36 so that the movable lens unit 32 moves forward when it is assembled, so that it falls within the standard of a predetermined viewing angle W. After adjusting the screwing amount of the adjusting screw 37 to the portion 36b and moving the contact member 64 back and forth to finely adjust the position, the adhesive 65a is injected into the through hole 65 and the contact member 64 is fixed. Is done.

  In addition to the effects of the first embodiment, the imaging device 30 of the present embodiment has an abutment member 64 fixed to the rear lens group frame 36 and an inclined surface 64b on the rear side inclined on the front side of the connecting rod 40. Since the surface 40a comes into surface contact with the surface 40a, the forward movement of the movable lens unit 32 can be reliably regulated.

  In the present embodiment, the contact member 64 is provided in the imaging device 30 only to restrict the movement of the movable lens unit 32 toward the front side. As the reason, in particular, as the maximum angle of view increases, a problem of the angle of view due to the optical path declination of the objective lens group occurs. Therefore, in the imaging device 30 of the present embodiment, the moving lens unit 32 moves forward. The forward movement of the moving lens unit 32 is ensured by the surface contact of the abutting member 64 finely adjusted and fixed at the time of assembly so that the position of the wide zooming end that stops is within the error range of the optical characteristics. Thus, it is possible to easily solve the problem of the angle of view due to the optical path deflection angle of the objective lens group.

  Of course, the abutment member 64 may be provided in the imaging device 30 so as to restrict the movement of the movable lens unit 32 to the rear side.

(Third embodiment)
Next, a third embodiment of the present invention will be described below based on FIG. 8 and FIG.
FIGS. 8 and 9 relate to the third embodiment of the present invention, and FIG. 8 is a partially enlarged cross-sectional view of the imaging apparatus showing a state in which the position of the moving lens frame has moved forward. 9 is a partially enlarged cross-sectional view of the imaging apparatus at the time of assembly in which an adjustment member that adjusts the moving position of the moving lens frame to the front as a modification is fixed to the rear lens group frame. In the following description, the same reference numerals are used for the same configurations as those of the imaging device 30 of the first embodiment described above, and detailed descriptions of these configurations are omitted.

  As described in the second embodiment, the imaging device 30 according to the present embodiment uses the contact member shown in FIGS. 8 and 9 in order to restrict the movement of the movable lens unit 32 toward the front side. This is a configuration provided in the rear lens group frame 36.

  Specifically, as shown in FIG. 8, a screw hole portion 67 is formed on the front side of the rear group lens frame 36, and an adjustment screw 66 as an adjustment member here is screwed into the screw hole portion 67. It is worn. In addition, an adhesive 67 a for fixing the adjustment screw 66 is injected into the screw hole 67.

  When assembling, the imaging device 30 adjusts the position of the wide zooming end to the screw hole 67 of the rear lens group frame 36 so that the movable lens unit 32 moves forward and falls within the standard of the predetermined viewing angle W. After adjusting the screwing amount of 66 and moving the adjusting screw 66 back and forth to finely adjust the position of the end surface of the adjusting screw 66, the adhesive 67a is injected into the screw hole 67 and the adjusting screw 66 is fixed. Is done. That is, the adjustment screw 66 restricts the movement of the moving lens unit 32 on the front side by contacting the front surface of the connecting rod 40. In addition, the front part of the connecting rod 40 here serves as a movement position regulating surface on the front side.

  The imaging device 30 according to the present embodiment is in contact with the inclined surface 40a on the front side of the connecting rod 40 and the inclined surface 40a described in the first embodiment, and the front side of the moving lens unit 32. The adjustment screw 37 for restricting the movement of is not provided.

  Even with such a configuration, in addition to the effects of the first embodiment, the imaging device 30 of the present embodiment has the moving lens unit 32 of the moving lens unit 32 due to the contact between the end surface of the adjustment screw 66 and the front surface of the connecting rod 40. It is the structure which can restrict | limit forward movement reliably.

  In the present embodiment, the adjustment screw 66 is provided in the imaging device 30 only for restricting the movement of the movable lens unit 32 to the front side for the same reason as the second embodiment. Of course, an adjustment screw 66 that restricts the movement of the moving lens unit 32 to the rear side may be provided in the imaging apparatus 30.

  As shown in FIG. 9, the rear lens group frame 36 has a through hole 69 formed on the front surface side, and a contact member 68 as an adjusting member is inserted and disposed in the through hole 69. This is a configuration of a modified example in which the contact member 68 is fixed to the through hole 69 by the adhesive 69a.

  As described above, the imaging device 30 according to the modification of the present embodiment is inserted into the through-hole 69 of the rear lens group frame 36 through the contact member 68 and assembled after the adhesive 69a is injected into the through-hole 69. Air is fed into the through-hole 69 by the piston jig 110 that is movable by the microstage 100.

  Then, when the imaging device 30 is assembled, the contact member 68 together with the adhesive 69a is moved backward in the through hole 69 by the pressure of the air sent from the piston jig 110, and the movable lens unit 32 moves forward. In order to define the position of the wide zooming end so that it falls within the standard of the predetermined viewing angle W (within the error range), the end surface position of the contact member 68 is finely adjusted finely, and then the adhesive 69a is cured and applied. The contact member 68 is fixed to the through hole 69. That is, also in this case, the contact member 68 restricts the movement of the moving lens unit 32 on the front side by making contact with the front surface portion serving as the movement position restricting surface of the connecting rod 40.

  As described above, in the present modification, the movement restriction position on the front side of the moving lens unit 32 is precisely adjusted by precisely pressing the contact member 68 into the through hole 69 by the micro stage 100 and the piston jig 110. Can be fine-tuned.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described below with reference to FIGS.
10 to 12 relate to a fourth embodiment of the present invention, and FIG. 10 is a partially enlarged cross-sectional view of the imaging apparatus showing a state in which the position of the moving lens frame has moved forward, FIG. FIG. 12 is a partially enlarged cross-sectional view of the imaging apparatus showing a state where the position of the moving lens frame has moved backward, and FIG. 12 is a plan view of the moving lens frame as viewed from the front. In the following description, the same reference numerals are used for the same configurations as those of the imaging device 30 of the first embodiment described above, and detailed descriptions of these configurations are omitted.

  As described in the second and third embodiments, the imaging apparatus 30 according to the present embodiment also uses FIGS. 10 to 12 to restrict the movement of the movable lens unit 32 to the front side. The configuration is explained.

  As shown in FIGS. 10 to 12, the moving lens unit 32 of the present embodiment is provided with an abutting member 70 in the lower part of the moving lens frame 38 instead of the connecting rod 40 extending downward. . The abutting member 70 has a U-shaped cross section, and has a guide extension portion 71 that extends downward on the front side and is formed with a concave groove portion 71a from below.

  Further, the rear lens group frame 36 is formed with a through-hole portion 36c having a thread groove formed on the front surface portion. Further, on the inner surface (rear surface) of the front surface portion of the rear group lens frame 36, an inward flange-shaped step portion 36d is formed around the opening portion of the through hole portion 36c.

  A rod-shaped cored bar member 73 is press-fitted into the through-hole portion 36c so as to protrude from the inner surface side of the rear lens group frame 36, and an adjustment member that adjusts the position of the cored bar member 73 from the front side when assembled. Screws 74 are screwed. The core member 73 and the adjustment screw 74 are fixed by an adhesive in the through hole 36c after the position adjustment.

  As shown in FIG. 12, the cored bar member 73 is inserted into a groove 71 a formed in the guide extension part 71 of the abutting member 70 on the outer peripheral part extending from the inner surface of the rear group lens frame 36. In addition, the core metal member 73 has a coil spring 72 arranged on the outer periphery thereof. Further, the upper portion side of the groove 71 a is formed in an arc shape in accordance with the shape of the cored bar member 73.

  The coil spring 72 is disposed so that one end thereof is in contact with the step 36 d of the rear group lens frame 36 and the other end is in contact with the front surface of the abutting member 70, and urges the abutting member 70 rearward. .

  Further, the moving shaft body 54 of the actuator 62 according to the present embodiment is provided with an abutting member 54 a that abuts against the rear surface of the abutting member 70 at the tip. That is, the moving shaft body 54 is configured not to be connected to the abutting member 70, and when the actuator 62 moves forward, the front surface of the abutting member 54a abuts on the rear surface of the abutting member 70, The abutting member 70 is moved so as to be pushed forward.

  In addition, an inclined surface portion 70a constituting a movement position regulating surface similar to the inclined surface 40b of the connecting rod 40 described in each of the above embodiments is formed on the lower end rear surface portion of the abutting member 70. That is, the inclined surface portion 70 a abuts on the conical surface 37 a of the adjusting screw 37 and restricts the rearward movement of the abutting member 70.

  The imaging device 30 of the present embodiment configured as described above moves forward by the moving shaft body 54 of the actuator 62 against the biasing force of the coil spring 72 when the moving lens unit 32 moves forward. The abutting member 70 is pushed forward by the contact member 54a. As shown in FIG. 10, the moving lens unit 32 is restricted from moving forward by the moving lens unit 32 when the rear end surface of the metal core member 73 abuts against the front surface of the abutting member 70.

  Further, in the imaging device 30, when the moving lens unit 32 moves rearward, the abutting member 54 a that has pushed the abutting member 70 forward is moved backward from the abutting member 70 by the retreat of the moving shaft body 54 of the actuator 62. The abutting member 70 receives the urging force of the coil spring 72 and is pushed rearward. As shown in FIG. 11, the moving lens unit 32 is restricted from moving rearward by the inclined surface 70 a of the abutting member 70 against the conical surface 37 a of the adjusting screw 37.

  Even with such a configuration, in addition to the effects of the first embodiment, the imaging device 30 of the present embodiment has a moving lens unit that is in contact with the end surface of the cored bar member 73 and the front surface of the abutting member 70. It is the structure which can restrict | limit the movement to the front of 32 reliably. Here, the front portion of the abutting member 70 serves as a movement position regulating surface on the front side.

  Further, in the moving lens unit 32, the groove 71 a formed in the guide extension 71 of the abutting member 70 is guided straight by the cored bar member 73. Therefore, the imaging device 30 can be configured to further improve the straightness when the moving lens unit 32 moves back and forth.

  Further, in this embodiment, for the same reason as the second and third embodiments, the moving lens unit 32 is moved by the adjusting screw 74 at the time of assembly only to restrict the movement of the moving lens unit 32 to the front side. The image pickup apparatus 30 is provided with a mandrel member 73 that can adjust the wide end position of 32, but the tele end position of the moving lens unit 32 is adjusted by an adjusting screw 74 that restricts the movement of the moving lens unit 32 to the rear side. Of course, it does not matter if the free core member 73 is provided in the imaging device 30.

(Fifth embodiment)
Next, a fifth embodiment of the present invention will be described below based on FIG. 13 and FIG.
FIGS. 13 and 14 relate to a fifth embodiment of the present invention, and FIG. 13 is a partially enlarged cross-sectional view of the imaging apparatus showing a state in which the position of the moving lens frame has moved forward. 14 is a partially enlarged cross-sectional view of the imaging apparatus showing a state in which the position of the moving lens frame of the modification has moved forward. In the following description, the same reference numerals are used for the same configurations as those of the imaging device 30 of the first embodiment described above, and detailed descriptions of these configurations are omitted.

  The imaging apparatus 30 of the present embodiment adjusts the fitting position of the front group lens unit 31 and the rear group lens frame 36 in the optical axis O direction during assembly, and the moving lens unit 32 moves forward and stops. The wide zooming end position is finely adjusted so that it falls within the error range of the optical characteristics.

  Specifically, when the front group lens unit 31 is fitted into the rear group lens frame 36, the imaging device 30 is arranged between the front group lens frame 34 and the rear group lens frame 36 as shown in FIG. In addition, a very thin ring plate 81 (three ring plates 81 shown in FIG. 13) constituting the adjustment member is interposed, and the position of the wide zooming end where the moving lens unit 32 moves forward and stops. Are finely adjusted so as to be within the error range of the optical characteristics. In other words, the front group lens unit 31 is finely adjusted in position before and after the arrow S in the figure and the moving lens unit 32 moves forward and is regulated at the position where the imaging device 30 is regulated. The zoom lens is positioned so as to be within an error range of the optical characteristics at the wide zooming end of the lens, and is fitted to the rear lens group frame 36.

  That is, in the imaging device 30, the distance between the front group lens unit 31 and the rear group lens frame 36 is finely adjusted by a plurality or a single ring plate 81, and the moving lens unit 32 moves forward and stops at the time of assembly. The position of the wide zooming end to be set is set within the error range of the optical characteristics.

  The imaging device 30 according to the present embodiment includes a movement restricting portion 36A that contacts the front surface of the connecting rod 40 of the moving lens unit 32 and a movement restricting portion 36B that contacts the rear surface of the connecting rod 40. The front-rear movement position is restricted.

  In the imaging apparatus 30 of the present embodiment configured as described above, it is assumed that the mounting accuracy of the movable lens unit 32 to the rear lens group frame 36 is slightly poor as in the above-described embodiments. In particular, it can be finely adjusted so that it is within the error range of the optical characteristics at the wide zooming end of the moving lens unit 32.

  Next, an imaging apparatus 30 according to a modification of the present embodiment will be described below based on FIG.

  As shown in FIG. 14, the front group lens unit 31 is formed with an inclined surface in which the rear end surface 34S of the front group lens frame 34 is inclined at a predetermined angle θ with respect to an axis orthogonal to the photographing optical axis O. Yes. The rear group lens frame 36 is provided with a protrusion 36S that is in contact with the rear end surface 34S of the front group lens frame 34 at a part of the front end surface.

  When the imaging device 30 is assembled, the front group lens unit 31 is rotated around the photographing optical axis O, and the imaging device 30 corresponds to the position where the projection 36S of the rear group lens frame 36 and the inclined rear end surface 34S of the front group lens frame 34 abut. Thus, the fitting position of the front group lens unit 31 in the optical axis O direction with respect to the rear group lens frame 36 is finely adjusted, and the front group lens unit 31 is fixed to the rear group lens frame 36 by the adhesive 82. In this way, the imaging device 30 may be configured so that the position of the wide zooming end where the movable lens unit 32 moves forward and stops during assembly is within the error range of the optical characteristics.

  That is, in the front group lens unit 31, the rear end surface 34S that contacts the protrusion 36S of the rear group lens frame 36 is an inclined surface having a predetermined angle θ, and therefore, according to the rotational position around the photographing optical axis O. The position relative to the rear lens group frame 36 is finely adjusted before and after the arrow S in the figure. The front group lens unit 31 is positioned so as to be within the error range of the optical characteristics of the wide zooming end of the imaging device 30 at the position where the movable lens unit 32 is moved forward and is regulated, and the rear group lens frame 36.

  The imaging device 30 of the present modification configured as described above cures the adhesive 82 in a state where the rear end surface 34S of the front group lens unit 31 and the projection 36S of the rear group lens frame 36 are in contact with each other. For this reason, it is possible to prevent the misalignment of the fitting position between the front group lens unit 31 and the rear group lens frame 36 caused by the sink of the adhesive 82 or the like.

(Sixth embodiment)
Next, a sixth embodiment of the present invention will be described below with reference to FIGS.
FIGS. 15 to 17 relate to the sixth embodiment of the present invention. FIG. 15 is a sectional view for explaining a state in which the rear lens group frame is held and fixed to the fixing jig. FIG. FIG. 17 is a view for explaining a slip prevention surface formed on the outer periphery of the group lens frame, and FIG. 17 is a view for explaining a V-shaped groove formed on the outer periphery of the rear group lens frame of a modified example. In the following description, the same reference numerals are used for the same configurations as those of the imaging device 30 of the first embodiment described above, and detailed descriptions of these configurations are omitted.

  By the way, the imaging device 30 is assembled by assembling the solid-state imaging device unit 46, the front group lens unit 31, the moving lens unit 32, and the rear group lens frame 36 at the time of assembling with predetermined optical characteristics, particularly when focusing. Are fixed with separate jigs and slid with each other to adjust the fitting position. At this time, as shown in FIG. 15, due to the tightening of the fixing jig 120 for fixing the rear group lens frame 36, the rear group lens frame 36 and the fixing jig 120 slide sideways, or the objective lens, CCD, etc. are damaged. There is a case to do.

  On the other hand, when the fixing jig 120 that completely surrounds and holds the rear portion of the rear lens group frame 36 is used, the holding and fixing performance of the rear lens group frame 36 is improved, but the heat capacity around the CCD is increased. There is a problem that the curing time of the thermosetting adhesive becomes long.

  In order to eliminate these problems, in the present embodiment, an example of a technique for improving the holding property of a fixing jig for holding and fixing the rear lens group frame 36 will be described below with reference to FIGS. 16 and 17. explain in detail.

  As shown in FIG. 16, the rear lens group frame 36 has an anti-slip surface 91 in which the surface of the outer peripheral portion held and fixed by the fixing jig 120 is formed with an uneven shape by knurling or the like, so that the fixing jig 120 is provided. The sliding resistance can be increased by increasing the frictional resistance.

  Further, as shown in FIG. 17, the rear lens group frame 36 may be provided with a non-slip V-shaped groove 92 so that it does not shift in the major axis direction on the outer peripheral portion held and fixed by the fixing jig 120. good. The fixing jig 120 has the same shape as the V shape of the groove portion 92 of the rear lens group frame 36 and includes a protrusion 121 that is engaged with the groove portion 92. Thereby, since the contact area of the fixing jig 120 and the rear group lens frame 36 can be reduced, it is possible to shorten the heat curing time of the adhesive.

  In addition, when the rear group lens frame 36 has a short overall length and a shield frame portion (not shown) is held and fixed by the fixing jig 120, the anti-slip surface 91 shown in FIG. A non-slip V-shaped groove 92 shown in FIG. 17 may be provided.

  The invention described in each of the above-described embodiments is not limited to the embodiments and modifications, and various modifications can be made without departing from the scope of the invention in the implementation stage. Further, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements.

  For example, even if several constituent requirements are deleted from all the constituent requirements shown in the embodiment, the problem to be solved by the invention can be solved, and the effect described in the effect of the invention can be obtained. A configuration from which this configuration requirement is deleted can be extracted as an invention.

The partially expanded sectional view of the imaging device which shows the state which the position of the block diagram which shows the whole electronic endoscope system which concerns on 1st Embodiment moved back Sectional drawing which shows the internal structure of the front-end | tip part of an electronic endoscope apparatus similarly Sectional drawing which shows the state of the moving lens frame which showed the structure of the imaging device and moved forward FIG. 3 is a cross-sectional view of the imaging apparatus showing a state where the position of the moving lens frame is moved backward from FIG. The partially expanded sectional view of the imaging device which shows the state which the position of the moving lens frame corresponding to FIG. 3 moved back 4 is a partially enlarged cross-sectional view of the imaging apparatus corresponding to FIG. 4, showing a state in which the position of the moving lens frame has moved forward. The partially expanded sectional view of the imaging device which shows the state which the position of the moving lens frame moved to the front based on 2nd Embodiment The partially expanded sectional view of the imaging device which shows the state which the position of the movement lens frame based on 3rd Embodiment moved forward The partially expanded sectional view of the imaging device at the time of the assembly which fixes the adjustment member which adjusts the moving position to the front of the moving lens frame which is a modification to the rear group lens frame The partially expanded sectional view of the imaging device which shows the state which the position of the moving lens frame moved to the front based on 4th Embodiment The partially expanded sectional view of the imaging device which shows the state which the position of the moving lens frame moved back The top view of the moving lens frame as seen from the front The partially expanded sectional view of the imaging device which shows the state which the position of the movement lens frame based on 5th Embodiment moved ahead The partially expanded sectional view of the imaging device which shows the state which the position of the moving lens frame of a modification moved forward Sectional drawing for demonstrating the state by which the rear group lens frame based on 6th Embodiment was hold | maintained and fixed to the fixing jig The figure for demonstrating the slip prevention surface formed in the outer peripheral part of a rear group lens frame similarly The figure for demonstrating the V-shaped groove part formed in the outer peripheral part of the rear group lens frame of the modification similarly

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Electronic endoscope system 2 ... Electronic endoscope apparatus 6 ... Tip part 9 ... Insertion part 10 ... Operation part 24 ... Tip rigid member 30 ... Imaging device 31 ... Front group lens unit 32 ... Moving lens unit 33 ... Rear group lens 34 ... Front group lens frame 35 ... Front group lens 36 ... Rear group lens frame 36b ... Screw hole Part 37a ... Conical surface 37 ... Adjustment screw 38 ... Moving lens frame 39 ... Moving lens 40a, 40b ... Inclined surface 40 ... Connecting rod 46 ... Solid-state image sensor unit 62- ..Actuators

Claims (4)

In an imaging device that changes the optical characteristics by moving a part of the objective lens back and forth by an actuator,
A fixed lens frame holding the objective lens, excluding the moving part of the lens;
A movable lens frame that holds the part of the lens inside the fixed lens frame, moves forward and backward along the photographic optical axis by the actuator, and has a movement position restricting surface formed in front and back in the movement direction;
An adjustment member that is provided on the fixed lens frame, abuts on the movement position restriction surface, restricts movement of the movement lens frame, and finely adjusts a restriction position at which the movement lens frame moves forward and backward;
An imaging apparatus comprising:   The adjustment member is an adjustment screw, and a regulation position where the movable lens frame moves forward and backward is finely adjusted according to an amount of screwing of the adjustment screw to the fixed lens frame. The imaging apparatus according to 1.   The position adjustment surface having a predetermined angle with respect to an axis orthogonal to the photographing optical axis, and the position adjustment in which the adjustment member is inclined with the same angle as the predetermined angle. The imaging device according to claim 1, further comprising: an imaging unit.   2. An uneven slip-preventing surface or a V-shaped circumferential groove is provided on an outer peripheral portion of the fixed lens frame or a solid-state imaging holding frame fitted to the fixed lens frame. 4. The imaging device according to any one of items 3.

Images