JP6030208B2 - Endoscope taking lens unit - Google Patents

Description

  The present invention relates to an endoscope photographing lens unit.

  In the medical field, many diagnoses and treatments using an electronic endoscope are performed. The electronic endoscope includes a camera module at the distal end of the insertion portion, and can capture image light in the patient's body and display it on a monitor or the like.

  Some camera modules have a mechanism for changing the focal length of a photographing lens and can switch the focal length between normal observation and magnified observation (see, for example, Patent Documents 1 and 2). In such a camera module, the photographing lens unit and the camera unit are integrated. The taking lens unit has a drive unit for moving a part of the taking lens in the optical axis direction to change the focal length.

  The drive unit electrically controls a drive unit having a shape memory alloy as in Patent Document 2 or a cam shaft drive type in which the lens moving frame is displaced in the optical axis direction by rotational displacement of the cam shaft as in Patent Document 1. Accordingly, there is a direct drive type in which the lens moving frame is displaced in the optical axis direction. However, in the case of the direct drive type, the lens to be moved is limited to one, unlike the cam shaft type. On the other hand, the cam shaft type has an advantage that a plurality of lenses can be moved simultaneously by increasing the cam groove and the lens moving frame engaged therewith.

JP 2002-58635 A JP 2009-294540 A

  Regardless of which drive method is adopted, when manufacturing a small camera module having an outer diameter (vertical x horizontal x length) of about 7 mm x 4 mm x 15 mm, for example, the dimensional accuracy of each component is a problem. It becomes. In particular, in the cam shaft type, the lens moving frame slides in the direction of the photographing optical axis in the housing along the two cylindrical centers, so that the dimensional accuracy of the sliding portion becomes a problem. For example, if the gap between the lens moving frame and the sliding guide surface of the housing is small, the operability is lowered and the movement becomes worse. If a motor that transmits torque to the camshaft is at the distal end of the insertion portion, torque is sufficiently transmitted to the camshaft, and even if the gap is small, there is no problem. However, in the endoscope camera module, it is difficult to arrange a motor for rotating the cam shaft at the distal end of the insertion portion in response to a request for reducing the diameter of the endoscope insertion portion in consideration of the burden on the patient. Therefore, if a motor or the like is disposed in the hand control unit and torque is transmitted to the camshaft by a wire, sufficient torque cannot be transmitted to the camshaft, so the gap between the lens moving frame and the sliding guide surface If is small, there is a problem that the lens moving frame cannot be moved.

  On the other hand, if the gap between the lens moving frame and the sliding guide surface is increased in order to improve operability and ease of movement, the movable lens will shake during operation and image blurring may occur during zoom operation. Will occur. When the blur increases, the movement is performed in an inclined state, and driving with low torque becomes difficult. In the worst case, the lens moving frame cannot be moved.

  In the camshaft system, a camshaft is provided in parallel with the photographic optical axis, and a lens moving frame needs to be engaged with the camshaft. The lens moving frame extends over the camshaft and the photographic optical axis. Be placed. In the housing that holds the lens moving frame in a movable manner, the area of the sliding guide surface where the lens moving frame and the inner surface of the housing come into contact increases, and the processing accuracy of the sliding guide surface is maintained within the design value range. There is a need. Moreover, for example, two lens bodies of 4 mmφ and 3.2 mmφ are arranged side by side in the horizontal direction and connected to a minute housing having a length of about 15 mm, a photographing lens storage hole and a cam shaft storage hole In addition, it is necessary to form a sliding space (moving hole) having an opening height of 1 mm, an opening width of 1.5 mm, and a depth of less than 10 mm. The sliding guide surface of the sliding space and the sliding surface of the lens moving frame have an area of, for example, a width (height) of 1 mm and a depth of 10 mm. A dimensional accuracy of about ± 5 μm is required in the gap. The dimensional accuracy of ± 5 μm is the limit accuracy that can be processed by normal cutting. For this reason, the finished housing and the lens moving frame are individually measured, a combination having a fitting accuracy within a predetermined range is found, and these are assembled and used as a pair. Therefore, the product yield rate (the number of finished products / the total amount of manufactured products) is a cause of a decrease.

  A review of the fitting accuracy and a review of the processing accuracy of each part in order to improve the product yield revealed a problem with the sliding structure of the lens moving frame.

  The present invention has been made in view of the above problems, and is capable of smoothly sliding a movable lens of an imaging lens unit for an endoscope, and can improve the product yield rate. An object is to provide a lens unit.

To achieve the above object, the present invention provides a photographic lens having a movable lens that is movable in the optical axis direction, a lens moving frame that holds the movable lens and moves in the optical axis direction, and an optical axis of the photographic lens. The lens moving frame is moved by a cam shaft that is provided in parallel and engages the lens moving frame, a shooting lens storage hole that stores the shooting lens, a cam shaft storage hole that stores the cam shaft, and a connecting surface that connects these storage holes. A housing having a moving hole for guiding, a first magnetic reaction material provided in the lens moving frame, and one of the connecting surfaces and outside the housing, arranged in the optical axis direction with respect to the moving range of the lens moving frame in the housing. And a second magnetic force reactive material that reacts with the first magnetic force reactive material by a magnetic force to attract or repel the lens moving frame in a direction orthogonal to the moving direction of the movable lens.

In the present invention, the magnetic reaction material includes a permanent magnet that itself generates a magnetic force in addition to a ferromagnetic material that reacts to the magnetic force and is attracted or repelled . The housing has an eight-letter shape when viewed from the front by connecting the first cylindrical portion having the photographing lens storage hole and the second cylindrical portion having the cam shaft storage hole side by side, and is formed between the first and second cylindrical portions. It is preferable to have a 2nd magnetic reaction material in a dent part. The photographing lens has a first fixed lens, a first movable lens, a second movable lens, and a second fixed lens that are sequentially arranged in the optical axis direction, and the lens moving frame holds the first movable lens. The first lens moving frame and the second lens moving frame holding the second movable lens are individually provided, the cam shaft has first and second cam grooves, and the first lens moving frame is provided in the first cam groove. It is preferable that the second lens moving frame is engaged with the second cam groove.

  According to the present invention, since the position of the lens moving frame is regulated by the magnetic force of the first magnetic reaction material and the second magnetic reaction material, the finished dimensional accuracy between the lens moving frame and the movement hole is improved as in the conventional case. It is no longer necessary to maintain high accuracy. Therefore, the number of lens moving frame combinations that match the distance between the connecting surfaces of the housings increases, and the product yield increases accordingly. Further, the lens moving frame is moved in the optical axis direction by the cam shaft in a state where the position of the lens moving frame is regulated by the magnetic force of the first magnetic reaction material and the second magnetic reaction material, so that the lens moving frame is moved. The lens moving frame can be moved by driving with a low torque of the camshaft. Further, the lens moving frame is not made immovable.

It is a perspective view which decomposes | disassembles and shows the photographic lens unit of this invention. It is the perspective view which looked at the photographing lens unit from the front diagonal. It is sectional drawing which decomposes | disassembles and shows a photographic lens unit. It is sectional drawing which follows the IV-IV line in FIG. 2 which shows the state which shifted the 1st and 2nd lens moving frame to the one connection surface of a movement hole. It is principal part sectional drawing of the camera module of a standard position. It is principal part sectional drawing of the camera module of an expansion position. It is a perspective view which decomposes | disassembles and shows a camera module. It is a perspective view which shows the external appearance of the whole camera module. It is sectional drawing which follows the IV-IV line | wire in FIG. 2 which shows the one-sided state of the 1st and 2nd lens moving frame in other embodiment. It is a perspective view which shows the structure of an electronic endoscope system. It is a perspective view which shows the front-end | tip part of an electronic endoscope.

  As shown in FIGS. 1 to 3, the photographing lens unit 11 of the present invention includes a housing 13, a photographing lens 14 housed in the housing 13, and a lens moving unit 15.

  The photographing lens 14 is configured by sequentially arranging a first fixed lens 21, a first movable lens 22, a second movable lens 23, and a second fixed lens 24 in the optical axis direction. Each of the fixed lenses 21 and 24 and each of the movable lenses 22 and 23 includes a lens frame 21a to 24a and one or a plurality of lens bodies 21b to 24b held by the lens frames 21a to 24a.

  The lens moving unit 15 includes a cam shaft 25, and a first lens moving frame 26 and a second lens moving frame 27 that slide on the cam shaft 25. The lens moving unit 15 moves the movable lenses 22 and 23 in the optical axis direction and changes the focal length of the photographing lens 14 to enable variable magnification photographing.

  The housing 13 is configured by arranging the first cylinder part 30 and the second cylinder part 31 in a direction orthogonal to the cylinder center direction and connecting them with a connecting part 32. As shown in FIG. 2, the outer diameter of the second cylindrical portion 31 is slightly smaller than the outer diameter of the first cylindrical portion 30, and has an 8-shape when viewed from the front. A photographing lens storage hole 33 is formed in the first tube portion 30, and the photographing lens 14 is stored in the hole 33. A lens moving part storage hole 34 is formed in the second cylinder part 31 to store the lens moving part 15. As shown in FIG. 3, a locking ring 34 a projects from the lens moving part storage hole 34.

  As shown in FIG. 2, the connecting portion 32 of the housing 13 is formed as an eight-shaped concave portion. A rectangular parallelepiped permanent magnet 50 is fixed to one outer surface 32a of the connecting portion 32 using, for example, an adhesive. As the permanent magnet 50, for example, one described in JIS-C2502 is used. For example, an alnico magnet, a ferrite magnet, a neodymium magnet, a samarium cobalt magnet, or the like is used. Since the permanent magnet 50 is disposed in the recess of the housing 13, the photographing lens unit 11 becomes compact.

  As shown in FIGS. 2 and 3, a moving hole 35 that connects the taking lens storage hole 33 and the lens moving part storage hole 34 is formed in the connection portion 32. The moving hole 35 has connecting surfaces 35a and 35b on both sides.

  As shown in FIGS. 1 and 3, the cam shaft 25 has two cam grooves 25a and 25b on the outer peripheral surface, and is engaged with the wire connecting hole 25c and the rear end outer peripheral surface along the axial center on the rear end surface. It has a flange 25d. As shown in FIG. 5, the distal end of the wire 18 for rotation driving is fixed in the wire connecting hole 25c. The wire 18 is put in the protective tube 19 and connected to a motor 80 (see FIG. 10) in the hand operating section 67. The motor 80 is driven and controlled by a controller (not shown) so as to rotate forward or reverse by operation of the seesaw switch 79 of the hand operation unit 67.

  As shown in FIGS. 1 and 3, a fixing ring 29 is attached to the tip of the cam shaft 25. With this fixing ring 29, as shown in FIG. 5, the cam shaft 25 rotates smoothly without tilting in the lens moving part accommodation hole. The locking flange 25d on the rear end side of the cam shaft 25 is locked to the locking ring 34a, and the cam shaft 25 is fixed to the tip of the wire 18, so that the cam shaft 25 comes out of the lens moving portion storage hole 34. There is no.

  As shown in FIGS. 1 and 3, the first lens moving frame 26 includes a guide tube 26a, a lens frame 22a, and an arm 26b that connects them, and these are integrally formed. Similarly, the second lens moving frame 27 has a guide tube 27a, a lens frame 23a, and an arm 27b, and is formed integrally. A first engagement pin 28a is attached to the guide tube 26a of the first lens moving frame 26, and the tip of the first engagement pin 28a enters the first cam groove 25a. A second engagement pin 28b is attached to the guide cylinder 27a of the second lens moving frame 27, and the second engagement pin 28b enters the second cam groove 25b.

  When the cam shaft 25 is rotated forward or backward, the first and second lens moving frames 26 and 27 are moved in the optical axis direction in the housing 13 through the engagement pins 28a and 28b due to this rotational displacement.

  5 and 6 illustrate switching of the focal length of the photographing lens 14, FIG. 5 shows a standard position, and FIG. 6 shows an enlarged position. In the enlarged position, the first lens moving frame 26 moves to the front side from the standard position, and the second lens moving frame 27 moves to the rear side from the standard position.

  As shown in FIG. 3, the photographing lens storage hole 33 has a first storage portion 33 a for storing the first fixed lens 21 and the first movable lens 22 in order from the front end to the rear end of the housing 13, and a second movable lens. A second storage portion 33b for storing the second storage lens 23 and a third storage portion 33c for storing the second fixed lens 24 are formed. A ring protrusion 33d serving as a partition is formed between the second storage portion 33b and the third storage portion 33c. The second storage portion 33b is formed slightly smaller than the inner diameter of the first storage portion 33a, and the second storage portion 33b and the third storage portion 33c are formed with the same inner diameter.

  The second antireflection cylinder 37 is accommodated in the second accommodating portion 33b. The second antireflection cylinder 37 is formed in a cylindrical shape, and has a slit 37a in the optical axis direction. The arm 27b of the second lens moving frame 27 enters the slit 37a, and the lens frame 23a of the second lens moving frame 27 enters the cylinder. The cylinder inner diameter is formed slightly larger than the outer diameter of the lens frame 23a, and the lens frame 23a does not contact the inner peripheral surface of the cylinder portion when the lens frame 23a moves in the cylinder portion.

  The first antireflection cylinder 36 is stored in the first storage portion 33a. The first antireflection tube 36 is also formed in the same manner as the second antireflection tube 37, and has a slit 36a. The difference from the second antireflection cylinder 37 is that a diaphragm plate 38 is integrally formed at the rear end. The rear end surface of the first antireflection tube 36 is locked by the step surface 33e between the first storage portion 33a and the second storage portion 33b, and is positioned when stored. In the first antireflection cylinder 36, the lens frame 22a of the first lens moving frame 26 moves.

  In order to prevent the occurrence of flare, the lens frame 21a of the housing 13, the lens frame 21a of the first fixed lens 21, the lens frame 22a of the first movable lens 22, and the lens frame of the second movable lens 23 are integrated. The second lens moving frame 27 having 23a, the lens frame 24a of the second fixed lens 24, the cam shaft 25, and the first and second antireflection cylinders 36 and 37 are blackened. Any of the known methods may be used for the black dyeing process. For example, the black layer 39 is formed by chemical treatment using a black dyeing treatment liquid. In addition, since the black layer 39 appears as a cross section with a slight thickness, the illustration with the thickness added is omitted. In the present embodiment, since the housing 13 is black-dyed, the second antireflection cylinder 37 may be omitted.

  The first lens moving frame 26 and the second lens moving frame 27 are made of a magnetic material, and are magnetic reaction materials that are attracted by magnetic force or repelled by magnetic force. As the magnetic material, a ferromagnetic material that is magnetized and exhibits strong magnetism, such as iron, nickel, cobalt, and alloys thereof, is used, and the lens moving frames 26 and 27 are configured by these ferromagnetic materials. . Instead of the entire moving frame made of these ferromagnetic materials, only the arms 26b and 27b may be made of these ferromagnetic materials, or a ferromagnetic material may be embedded in a part of the arms 26b and 27b.

  As shown in FIG. 4, after the photographing lens 14 and the lens moving unit 15 are assembled in the housing 13, the lens is moved by the attracting action by the magnetic force between the permanent magnet 50 and the lens moving frames 26 and 27 made of a ferromagnetic material. The frames 26 and 27 are urged by one connecting surface 35a of the moving hole 35, and a gap C1 is formed between the other connecting surface 35b and the lens moving frames 26 and 27. Thus, the lens moving frames 26 and 27 can be moved using only one of the connecting surfaces 35a as a sliding guide surface.

  In the conventional case, the arms 26b of the first and second lens moving frames 26, 27 are moved so that the first and second lens moving frames 26, 27 move smoothly in the optical axis direction by the rotation of the cam shaft 25. These parts are measured so that the gap (W1-t1) at the time of fitting with the thickness t1 of 27b and the inter-surface distance W1 between the connecting surfaces of the moving hole 35 is 5 μm, for example, within the 5 μm gap. Those to be combined are selected and used as a pair. Accordingly, a combination that does not form a pair is generated, causing a reduction in product yield. In the present invention, both of the connecting surfaces 35a and 35b on both sides of the moving hole 35 are used as sliding guide surfaces. Therefore, it is necessary to maintain the gap (W1-t1) between the thickness t1 of the arms 26b and 27b of the lens moving frames 26 and 27 and the distance W1 between the connecting surfaces of the moving hole 35 at 5 μm strictly and accurately. However, the number of pairs that can be combined increases accordingly, and the product yield rate improves.

  As shown in FIG. 9, in the second embodiment of the present invention, permanent magnets 53 are provided on the arms 51 b and 52 b of the first and second lens moving frames 51 and 52, and are provided in the recesses of the connecting portion 32 of the housing 13. The permanent magnet 50 attracts the arms 51b and 52b so as to be urged to one connecting surface 35a, and a gap C1 is formed between the other connecting surface 35b and the arms 51b and 52b. Although not shown, each arm may be urged toward the other connecting surface by using a repulsive force instead of attraction by magnetic force. Further, although the permanent magnet 50 is provided only in one concave portion of the housing 13, a permanent magnet is provided on the opposite side, and the repulsive force due to the magnetic force between the permanent magnet and the permanent magnet of each lens moving frame is provided. Further, each arm may be biased to one connecting surface.

  In each of the above embodiments, the lens moving frame is formed of a magnetic material, or the lens moving frame is provided with a permanent magnet. Instead, the engaging pins 28a and 28b are configured of a magnetic material or a permanent magnet. May be. In this case, since the permanent magnet is separately embedded, it is not necessary to form a mounting hole in the lens moving frame itself or to attach the permanent magnet to the mounting hole, and the configuration is simplified accordingly.

  In the first embodiment, the housing 13 is also black-dyed, but the housing 13 may be assembled in a state of a cut surface without being black-dyed. In this case, in order to surely suppress the occurrence of flare, it is preferable to black-process the antireflection tubes 36 and 37. The housing 13 has a complicated shape in which two cylindrical portions 30 and 31 are connected side by side and a bag-like moving hole 35 is formed inside the connecting portion 32, and the outer diameter is 7 mm × 4 mm × 15 mm. It is a minute part. For this reason, when black dyeing is performed, the inner surface of the housing 13, particularly the first and second connecting surfaces 35 a and 35 b on both sides of the moving hole 35, do not smoothly circulate the processing liquid during black dyeing. The thickness of the black layer 39 is not formed, or even if it is formed, it is slightly formed, or on the contrary, it is formed thick, so that the thickness becomes non-uniform in the entire region of the coupling surfaces 35a and 35b. Therefore, even if dimensional accuracy is obtained by cutting, variation in dimensional accuracy is caused by this black dyeing process. Due to the variation in the dimensional accuracy, the number of pairs created by combining the processing accuracy within a certain range is reduced, which causes a problem that the product yield rate is lowered. In order to eliminate this, it is preferable from the viewpoint of improving the product yield that the housing 13 is assembled in the state of the cut surface without being black dyed because the number of pairs that become acceptable products further increases.

  Further, in the above embodiment, the housing 13 is black-dyed and assembled as it is, or it is assembled without black-dying, but in addition to this, only one connecting surface 35a serving as a sliding guide surface is masked. Therefore, the other surface may be black-dyed. In addition, the black-dyed sliding guide surface may be recut to be a cut surface without masking.

  As shown in FIG. 3, the second cylindrical portion 31 is formed longer than the first cylindrical portion 30 in order to accommodate the cam shaft 25. The leading ends of the second cylindrical portions 31 are aligned with each other, and the rear ends of the second cylindrical portions 31 are formed so as to protrude rearward from the rear ends of the first cylindrical portions 30. A space is generated on the rear end side of the first cylindrical portion 30 due to the step difference between the two cylindrical portions 30 and 31. Using this space, as shown in FIG. 7, a CCD unit (imaging device unit) 12 is attached to the photographing lens unit 11 to constitute a camera module 10.

  For this reason, the rear half 30a of the outer peripheral surface of the first cylindrical portion 30 of the housing 13 is formed to have a slightly smaller outer diameter than the front half 30b of the outer peripheral surface, and between the front half 30b and the rear half 30a. A step surface 30c is formed. An attachment cylinder portion 40a of the prism holder 40 of the CCD unit 12 is externally fitted and attached to the rear half 30a of the outer peripheral surface. Thus, by arranging the prism 41 in the space on the rear end side of the first tube portion 30, the camera module 10 can be configured compactly as a whole.

  The CCD unit 12 includes a prism holder 40, a prism 41, a CCD (CCD type image sensor) 42, a circuit board 43, a transmission cable 44, a cable connector 45, and a sealing agent (not shown) for sealing wiring. Have. The hole 48 formed in the housing 13 is for injecting adhesive and inserting screws when the antireflection tubes 36 and 37 and the second fixed lens 24 are fixed in the photographing lens storage hole 33. Provided as needed.

  The prism holder 40 includes a mounting cylinder portion 40a and a prism mounting frame 40b. As shown in FIG. 5, the prism 41 is composed of a right-angle prism having five surfaces, that is, an incident surface 41a and an output surface 41b intersecting at right angles, a reflecting surface 41c formed of an inclined surface, and both side surfaces 41d. The prism mounting frame 40b has an opening 40c through which incident light from the photographic lens 14 passes, and first and second prism mounting position restricting pieces 40d and 40e (see FIGS. 5 and 8) on the rear end surface. As shown in FIG. 8, the first position restricting piece 40d abuts on the side surface 41d of the prism 41, and the second position restricting piece 40e abuts on a ridge line 41f where the incident surface 41a and the exit surface 41b are orthogonal to each other. The prism 41 can be positioned on the prism mounting frame 40b by the side surface 41d and the ridge line 41f of the prism 41 coming into contact with the two position restricting pieces 40d and 40e.

  A CCD 42 is attached to the emission surface 41 b of the prism 41, and a circuit board 43 for driving the CCD 42 is attached to the slope of the prism 41 with an adhesive. The CCD 42 and the circuit board 43 are connected to a connection or a flexible wiring circuit board. The connection of the transmission cable 44 is connected to the circuit board 43. The transmission cable 44 is formed by covering a signal line with a shield line, and the shield line is covered with a covering cord. The circuit board 43 may be divided and arranged at an appropriate position.

  One end of the cable connector 45 is fixed to the covering cord of the transmission cable 44 with an adhesive. Further, the other end of the cable connector 45 is formed with a locking claw 45a bent, and this locking claw 45a is locked in a locking hole 47 formed in the second position regulating piece 40e. In order to protect the cable connector 45, the connection covered by the CCD 42, and the circuit board 43, a sealing agent (not shown) is injected into these gaps as necessary and solidified. The cable connector 45 may have a frame shape in addition to the plate shape.

  The camera module 10 configured as described above is attached to the distal end portion 66a of the electronic endoscope 60 as shown in FIG. The electronic endoscope system 59 includes an electronic endoscope 60, a processor device 61, and a light source device 62. The electronic endoscope 60 includes a flexible insertion portion 66 that is inserted into a body cavity of a patient, a hand operation portion 67 that is connected to a proximal end portion of the insertion portion 66, a processor device 61, and a light source device 62. It has a connector 69a to be connected, a hand operating section 67, and a universal cord 69 that connects the connectors 69a.

  The insertion portion 66 includes a distal end portion 66a, a bending portion 66b, and a flexible portion 66c in order from the distal end. The tip portion 66a is configured by covering a tip portion body made of a hard resin with a tip cap made of a soft resin, and covering the tip portion body and a metal tip tube of the curved portion 66b following the tip portion body with a tube. The curved portion 66b has a unit in which each node ring is pin-coupled, and the whole is curved. The bending portion 66b is bent at an arbitrary angle in the vertical and horizontal directions by the rotation operation of the angle knob 70 of the hand operation portion 67. Thereby, the observation part in a body cavity can be imaged with the camera module 10 with the front-end | tip part 66a facing the desired direction in a body cavity. The soft portion 66c is a portion that connects the hand operating portion 67 and the bending portion 66b in a narrow shape with a long diameter, and has flexibility.

  As shown in FIG. 11, in addition to the forceps outlet 72, an observation window 73, illumination windows 74a and 74b, and an air / water supply nozzle 75 are provided on the distal end surface of the distal end portion 66a. In addition, a water jet outlet and other nozzles are provided as necessary.

  The hand operation unit 67 includes various operation members such as an angle knob 70, an air / water supply button 76, a suction button 77, a release button 78, and a seesaw switch 79 for zoom operation. The angle knob 70 bends the distal end portion 66a of the insertion portion 66 in the vertical and horizontal directions by a rotation operation. The air / water supply button 76 ejects air or water from the air / water supply nozzle 75 by a pressing operation. The suction button 77 sucks a suction target such as a liquid or tissue in the body from the forceps outlet 72 by a pressing operation. The release button 78 records an observation image as a still image by the camera module 10 by a pressing operation. The seesaw switch 79 rotates the motor 80 forward or backward and transmits this rotation to the camshaft 25 via the wire 18 to switch the photographing lens 14 between standard and magnified photographing.

  The processor device 61 is electrically connected to the light source device 62 and comprehensively controls the operation of the electronic endoscope system 59. The processor device 61 supplies power to the electronic endoscope 60 through the universal cord 69 and the transmission cable 44 inserted into the insertion portion 66, and controls the driving of the camera module 10 at the distal end portion 66a. Further, the processor device 61 receives a signal from the camera module 10 via the transmission cable 44 and performs various processes to generate image data. A monitor 81 is connected to the processor device 61. The monitor 81 displays an observation image based on the image data from the processor device 61.

  In the above-described embodiment, the example in which the two movable lenses 22 and 23 are used as the photographing lens unit 11 has been described. However, the number of movable lenses may be one or more. In this case, the lens moving frame is slidably guided on the second connecting surface. Further, the present invention may be applied to a case where the lens moving frame is moved by focusing control in addition to the scaling process. In addition, although the cam shaft 25 is rotationally driven by the wire 18, in the case of a type in which a motor may be housed at the distal end of the insertion portion, the cam shaft 25 may be directly driven by the motor instead of the wire drive. Further, although an example using a CCD as an image sensor has been described, a CMOS image sensor may be used as the image sensor. Moreover, although the said embodiment demonstrated the example which applies this invention to a medical endoscope, you may apply this invention to an industrial endoscope.

DESCRIPTION OF SYMBOLS 10 Camera module 11 Shooting lens unit 12 CCD unit 13 Housing 14 Shooting lens 15 Lens moving part 21 First fixed lens 22 First movable lens 23 Second movable lens 24 Second fixed lens 25 Cam shaft 26 First lens moving frame 27 First Two-lens moving frames 28a, 28b Engaging pins 30, 31 Tube portion 32 Connecting portion 35 Moving holes 35a, 35b Connecting surfaces 37, 38 Antireflection tube 39 Black layer 40 Prism holder 41 Prism 42 CCD (CCD type image sensor)
44 Transmission cable 45 Cable connector 51, 52 Lens moving frame 59 Electronic endoscope system 60 Endoscope 66 Insertion section 67 Hand operation section 80 Motor

Claims (2)

A photographic lens having a movable lens movable in the direction of the optical axis;
A lens moving frame that holds a movable lens and moves it in the optical axis direction;
A cam shaft provided parallel to the optical axis of the photographing lens and engaged with the lens moving frame;
A housing having a photographing lens housing hole for housing the photographing lens, a cam shaft housing hole for housing the cam shaft, and a moving hole for moving and guiding the lens moving frame by a connecting surface connecting the housing holes;
A first magnetic reaction material provided on the lens moving frame;
One of the connecting surfaces and outside the housing is arranged in the optical axis direction with respect to the movement range of the lens moving frame in the housing , and reacts with the first magnetic force reaction material by magnetic force, An endoscope imaging lens unit comprising: a second magnetic reaction material that attracts or repels the lens moving frame in a direction orthogonal to the moving direction of the movable lens. The housing has an eight-letter shape when viewed from the optical axis direction by connecting the first cylindrical portion having the photographing lens storage hole and the second cylindrical portion having the camshaft storage hole side by side. The photographic lens unit for an endoscope according to claim 1, wherein the second magnetic force reaction material is provided in a recess portion between the second cylindrical portion and the second cylindrical portion.

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