JP2005013277A - Imaging device for endoscope and method of forming thin film section disposed in imaging device for endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable to prevent a lens system disposed in a frame to be exposed to steam while autoclave sterilization is performed and to improve a precision of processing of brazing of parts which constitute the above frame. <P>SOLUTION: An airtight lens unit 30 is constituted to include an inner lens unit 31, a front end lens 32, a front end lens frame 33, a first pipe 34, a ceramic frame 35, a second pipe 36, a lens holder 37, a lens 38 and a rear end lens 39. A metallizing treatment is applied on outer peripheral surfaces of the front end lens 32 and the rear end lens 39. Inner peripheral surfaces of the front end lens frame 33 and the lens holder 37 are disposed with thin film sections 10 made of a vapor deposition material such as nickel or copper which is vapor-deposited by physical vapor-phase growth method. The front end lens 32 and the rear end lens 39 which are applied with the metallizing treatment are respectively connected to the inner peripheral surfaces of the front end lens frame 33 and the lens holder 37 by soldering with brazing material, pewter or the like. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an endoscope imaging device used for an endoscope capable of autoclave sterilization and a method for forming a thin film portion provided in the endoscope imaging device.
[0002]
[Prior art]
Conventionally, by inserting a long and thin insertion portion into a body cavity, the inside of a body cavity can be observed, and various medical treatments can be performed using a treatment instrument inserted into a treatment instrument channel as necessary. Endoscopes are widely used.
[0003]
In this endoscope, an insertion portion is inserted into a body cavity for observation, and various treatments and treatments are performed using a treatment instrument inserted into a treatment instrument channel. For this reason, when an endoscope that has been used once is reused, it is necessary to wash and disinfect after completion of the examination because it is necessary to prevent infection between patients.
[0004]
In recent years, autoclave sterilization (high-pressure steam sterilization), which can be used immediately after sterilization, which involves complicated work, and has a low running cost, is becoming the mainstream of disinfection sterilization processing for endoscope devices.
[0005]
In this autoclave sterilization, a vacuum is applied before the sterilization process, a high-temperature steam is sterilized in a short time in a short time, and a vacuum is applied for drying after the sterilization process is completed. As an example of this autoclave sterilization, US standard ANSI / AAMIST 37-1992 stipulates that the sterilization process is performed at about 2 atm and 132 ° C. for 4 minutes. However, high-pressure steam permeates most polymer materials such as resin, rubber, and resin adhesive.
[0006]
In general, in a flexible mirror having a soft part and a movable part, an operation part, an insertion part, a bending part, and the like are mainly composed of a polymer material. For this reason, even if it is possible to maintain water tightness at 1 atm, water vapor can easily enter under high pressure. In addition, epoxy resin, which is a commonly used adhesive, also permeates high-pressure steam sterilized by autoclave. Furthermore, epoxy resins have the property of deteriorating by direct contact with high pressure steam. For this reason, it is considered that cracks occur in the cured adhesive due to the penetration of water vapor. In addition, since autoclave sterilization is performed at a high temperature, cracks may occur in the cured adhesive due to the stress applied between the parts due to the difference in coefficient of thermal expansion of each material.
[0007]
In other words, when the soft mirror is sterilized by autoclave, high-pressure steam penetrates the adhesive such as the optical window joint and penetrates into the optical system, and the lens surface becomes cloudy, or the glass material or lens forming the lens There is a risk of deteriorating the coating applied to.
[0008]
In order to solve these problems, Japanese Patent Laid-Open No. 6-209898 discloses that the optical window member is joined airtightly by soldering, brazing, or the like instead of adhesive fixing with a resin adhesive. Further, there is shown a technique in which a surface treatment (wet plating) such as a gold plating for soldering is performed on a groove portion of a stainless steel inner tube and a tip cover glass holding member. In addition, if the inner tube is made of a metal such as brass, good brazing can be performed without plating, but a metal with good solderability such as brass may be rusted by autoclave sterilization and lose resistance. is there. In order to prevent this, the inner tube is made of stainless steel having steam resistance.
[0009]
Japanese Patent Laid-Open No. 2002-253486 discloses that an optical window member and a frame member are heated in a hydrogen furnace atmosphere for the purpose of solving the problem of contamination and corrosion due to residual flux as in the case of soldering using a conventional flux. The method of soldering is shown.
[0010]
Further, as a method of forming a uniform film portion with good adhesion, for example, vapor deposition materials such as chromium, nickel, copper, etc. are evaporated by a physical method such as high temperature heating, sputtering, etc. There is known a physical vapor deposition method (hereinafter referred to as PVD) in which a film portion is condensed to form a film portion.
[0011]
[Patent Document 1] JP-A-6-209898 (page 2-3, FIG. 1)
[0012]
Japanese Patent Laid-Open No. 2002-253486 (page 2-4, FIG. 2-4)
[Problems to be solved by the invention]
However, in the endoscope disclosed in Japanese Patent Application Laid-Open No. 6-209898, when solder flows on the outer periphery of the cover glass holding member, the outer diameter changes and cannot be fitted to other parts. For this reason, it is necessary to remove the surface treatment such as plating of a portion where the solder is not desired to flow by an additional process, and there is a problem such as a reduction in image quality due to a reduction in processing accuracy.
[0013]
Further, in the method of heating and soldering in a hydrogen furnace atmosphere disclosed in Japanese Patent Application Laid-Open No. 2002-253486, the plating film thickness provided to make the solder wettability constant on the soldered surface of the metal frame is controlled. There is a drawback that high technology is required for this plating.
[0014]
Furthermore, in the PVD, a technique for forming a homogeneous film part on a planar member such as a substrate has been established, but it has been difficult to form a homogeneous film part on a curved surface.
[0015]
The present invention was made in view of the above circumstances, and when performing autoclave sterilization, the optical member constituting the optical system provided inside the frame is prevented from being exposed to water vapor, and It is an object to provide an endoscope imaging apparatus capable of improving the brazing accuracy of parts constituting the frame and reducing the manufacturing cost, and a method for forming a thin film portion provided in the endoscope imaging apparatus. Yes.
[0016]
[Means for Solving the Problems]
An endoscope imaging apparatus according to the present invention includes a metal lens frame in which an optical member is disposed at least at one end, or a ceramic ceramic frame that is disposed by being fitted to a metal metal frame. An endoscopic imaging device,
A thin film portion having a predetermined thickness that improves solder wettability using a physical vapor deposition method is provided on a fitting surface of the lens frame with the optical member and a fitting surface of the ceramic frame with the metal frame. .
According to this configuration, the joining of the optical member and the lens frame or the joining of the metal frame and the ceramic frame can be performed by soldering such as solder.
[0017]
In addition, a method for forming a thin film portion provided in an endoscope imaging apparatus includes an arrangement step of arranging a frame member at a predetermined position of a frame jig, and a vapor deposition apparatus having a target of the frame member arranged in the frame jig Using the physical vapor deposition method, the installation step to be installed inside, the frame jig is moved with respect to the target, and the frame member arranged on the frame jig is rotated by a predetermined amount along with the movement. And a film part forming step of forming a thin film part on the peripheral surface of the frame member.
According to this forming step, a uniform thin film portion having a predetermined thickness dimension is formed on the peripheral surface of the frame member.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
1 to 12 relate to a first embodiment of the present invention, FIG. 1 is a diagram for explaining the configuration of an endoscope, FIG. 2 is a cross-sectional view for explaining an endoscope imaging device, and FIG. FIG. 4 is a diagram showing a state in which the tip lens is joined to the tip lens frame, FIG. 5 is a diagram showing a state in which a masking member is disposed on the ceramic frame, and FIG. FIG. 7 is a diagram illustrating a process of providing a thin film portion on the outer peripheral surface of a ceramic frame disposed on a jig, FIG. 8 is a diagram illustrating a state in which a masking member is disposed on a tip lens frame, and FIG. 9 is a diagram for explaining the tip lens frame in a state where it is arranged on a jig, FIG. 10 is a diagram for explaining the positional relationship between the tip lens frame arranged on the jig and the target, and FIG. 11 is a thin film portion on the inner peripheral surface. FIG. 12 is a diagram for explaining another method for providing the thin film portion on the inner peripheral surface. Kicking is a diagram for explaining another method.
[0019]
6A is a diagram for explaining a procedure for arranging the ceramic frame on the jig, FIG. 6B is a diagram for explaining the ceramic frame in a state of being arranged on the jig, and FIG. 7A is a sputtering apparatus. FIG. 7B is a view for explaining the positional relationship between the ceramic frame placed on the jig and the target.
[0020]
As shown in FIG. 1, the endoscope 1 according to the present embodiment mainly includes an insertion portion 11, an operation portion 12, a universal cord 13, a light guide connector 14, a camera cable 15, and a camera connector 16. Has been.
[0021]
The insertion portion 11 is a portion to be inserted into the body, and is elongated and flexible. The operation portion 12 is provided at the proximal end portion of the insertion portion 11. The universal cord 13 extends from the operation unit 12. The light guide connector 14 is provided at the end of the universal cord 13. The camera cable 15 is branched from the light guide connector 14. A camera connector 16 is provided at the end of the camera cable 15. The camera cable 15 is connected to a camera control unit (not shown) via a camera connector 16.
[0022]
The insertion portion 11 is configured by connecting a flexible tube portion 17, a bending portion 18, and a distal end hard portion 19 in order from the operation portion 12 side. The operation portion 12 is provided with an angle lever 21 for remotely operating the bending portion 18.
[0023]
The flexible tube portion 17 is formed of a soft member. The bending portion 18 is configured by connecting a plurality of bending pieces, and bends in the vertical and horizontal directions by operating the angle lever 21, for example. The distal end hard portion 19 is formed of a hard member.
[0024]
The light guide connector 14 is provided with a base 22 that communicates with the internal space of the endoscope 1. The endoscope 1 has a watertight structure, and by attaching an adapter (not shown) to the base 22, the internal space of the endoscope 1 and the outside of the endoscope are in communication with each other.
[0025]
An endoscope imaging apparatus will be described with reference to FIG.
As shown in the drawing, the endoscope imaging device 3 includes an airtight lens unit 30, a solid-state imaging device unit 50, a signal cable 61, an outer frame 62, a back cover 63, and a heat-shrinkable tube 64. Thus, it is configured as an imaging unit.
[0026]
The hermetic lens unit 30 is provided with a plurality of lenses, which will be described later, at predetermined positions. The solid-state imaging device unit 50 is provided with a solid-state imaging device 51 that photoelectrically converts an optical image formed on the imaging surface through the airtight lens unit 30. The signal cable 61 transmits an electrical signal photoelectrically converted by the solid-state image sensor 51 to a camera control unit connected to the camera connector 16.
[0027]
The airtight lens unit 30 includes an internal lens unit 31, a front lens 32, a front lens frame 33, a first pipe 34, a ceramic frame 35, a second pipe 36, a lens holder 37, a lens 38, and a rear end lens 39. Consists of.
[0028]
The internal lens unit 31 houses a lens group 42 configured by arranging a plurality of lenses on an internal lens frame 41. The internal lens frame 41 is made of, for example, an aluminum alloy.
[0029]
The front lens frame 33, the first pipe 34, the second pipe 36, and the lens holder 37 are substantially tubular and are made of a material having high resistance to water vapor such as stainless steel. The ceramic frame 35 is made of a dense ceramic such as alumina having high resistance to water vapor.
[0030]
A distal lens 32 that constitutes the most distal portion of the airtight lens unit 30 is disposed on the distal end side of the internal lens unit 31. The tip lens 32 is made of, for example, sapphire glass or quartz glass having high resistance to water vapor. Further, the outer peripheral surface of the tip lens 32 is subjected to metallization processing.
[0031]
For example, a vapor deposition material such as chromium, nickel, copper, or the like is deposited on the inner peripheral surface of the front lens frame 33 to be a joint surface with the front lens 32 by physical vapor deposition (hereinafter referred to as PVD). The formed thin film portion 10 is provided. This PVD is one of dry plating, and a film portion is formed on a product by accelerating and colliding the metal ionized in a low or high vacuum or a rare gas such as argon or nitrogen with the product.
[0032]
The tip lens 32 subjected to the metallization process is fixed to the inner peripheral surface of the tip lens frame 33 on which the nickel thin film portion 10 is formed, for example, by brazing such as brazing or soldering. Thereby, the outer peripheral surface of the front end lens 32 and the inner peripheral surface of the front end lens frame 33 are airtightly bonded, and gas can be prevented from entering through the bonded portion.
[0033]
A first pipe 34 is fitted and arranged inside the front lens frame 33 and joined by welding, for example. Further, the tip end portion of the ceramic frame 35 is fitted and disposed inside the first pipe 34 and joined by welding, for example. Further, the base end portion of the ceramic frame 35 is fitted and arranged inside the second pipe 36 and joined by welding, for example. The second pipe 36 is fitted and arranged on the inner side of the front end side of the lens holder 37, and is joined by welding, for example.
[0034]
The tip lens frame 33, the first pipe 34, the ceramic frame 35, the second pipe 36, and the lens holder 37 are joined in a narrow sense by laser or the like, brazing such as brazing or soldering, fusion welding, or pressure welding. In addition, airtight bonding is performed using metal bonding or the like, and gas is prevented from entering through the bonding portion.
[0035]
At least the welded portion of the ceramic frame 35 is subjected to surface treatment by an active metal method, Mo-Mn baking, wet plating, PVD, or the like in advance so that welding is possible.
[0036]
The internal lens unit 31 is inserted inside the ceramic frame 35 and is integrally fixed by bonding or the like while being positioned with respect to the solid-state image sensor 51 of the solid-state image sensor unit 50.
[0037]
The rear end lens 39 is joined to the inner peripheral surface of the base end side of the lens holder 37 by brazing such as brazing or soldering. The outer peripheral surface of the rear end lens 39 is metalized similarly to the front end lens 32. On the other hand, a thin film portion 10 made of nickel, for example, is provided on the inner peripheral surface of the lens holder 37 by PVD. Then, the rear end lens 39 subjected to metallization and the lens holder 37 provided with the thin film portion 10 are bonded and fixed by brazing such as brazing or soldering.
[0038]
The rear end lens 39 is also made of, for example, sapphire glass or quartz glass, which has high resistance to water vapor. In the present embodiment, the front lens 32 and the rear lens 39 are flat cover glasses, but may be curved lens shapes. Further, a lens 38 is attached to the inside of the lens holder 37 through a ring-shaped member 40 so as to provide a gap with the rear end lens 39.
[0039]
In this way, the joint portions of the front lens 32, the front lens frame 33, the first pipe 34, the ceramic frame 35, the second pipe 36, the lens holder 37, and the rear lens 39 constituting the airtight lens unit 30 are provided. By airtightly joining by brazing or the like, the internal space of the airtight lens unit 30 can be made into an airtight space where no high-pressure steam enters even if autoclave sterilization is performed.
[0040]
As a result, a plurality of lenses constituting the lens group 42 provided in the hermetic space of the hermetic lens unit 30 and a glass material of the lens 38, a coating applied to these lenses, and a lens fogging occur. This prevents the deterioration of the image due to the cause of these problems, and provides a good endoscopic observation image.
[0041]
Next, the solid-state image sensor unit 50 will be described.
The solid-state image sensor unit 50 is configured by housing a solid-state image sensor 51 and a circuit board 52 in a case 53. The solid-state image sensor 51 is connected to the circuit board 52 via wire bonding or a flexible wiring board. The circuit board 52 is mounted with an electronic component such as a capacitor and an IC for amplifying an electric signal. A lead pin 54 that is electrically connected to the circuit board 52 is provided on the base end side of the case 53. The lead pin 54 is electrically connected to the signal cable 61 outside the case 53.
[0042]
A glass lid 55 is bonded to the light receiving portion of the solid-state imaging device 51 with a transparent adhesive that is cured by ultraviolet rays. The glass lid 55 is for preventing dust and scratches on the light receiving portion of the solid-state image sensor 51. The front end side surface of the glass lid 55 is bonded and fixed to the rear end lens 39.
[0043]
The ceramic frame 35, the second pipe 36, and the lens holder 37 hold the rear end lens 39 joined to the glass lid 55, and fit and position the inner lens unit 31 to thereby focus the optical system. Aligning. Thus, the endoscope imaging device 3 is configured by aligning the internal lens unit 31 and the solid-state imaging device 51.
[0044]
A distal end portion of a metal outer frame 62 is attached to the outer periphery on the proximal end side of the lens holder 37. A back cover 63 is attached to the inner periphery of the base end portion of the outer frame 62. The back cover 63 has an opening 65 through which the signal cable 61 is passed.
[0045]
The back cover 63 is filled with an adhesive 66. The adhesive 66 fixes the solid-state image sensor unit 50 and the signal cable 61 to the back cover 63. Further, the outer surface of the outer frame 62 and the back cover 63 and the base end side of the lens holder 37 are covered with a heat-shrinkable tube 64 having electrical insulation.
[0046]
When the members constituting the endoscope imaging device 3 are joined together by welding, fusion welding, or pressure welding, the endoscope imaging device 3 has a built-in material that is easily damaged such as a lens or an electronic component. For this reason, it is difficult to reduce the gap between the fitting portions by deforming them after fitting the members of the same material. In addition, since it is necessary to reduce the outer diameter of the endoscope imaging device 3, it is difficult to increase the thickness. For this reason, the thickness of the welded portion is thin and the gap between the fitting portions is large, making it difficult to weld the fitting portions in an airtight manner. Therefore, as one of the means for reducing the gap, the outer member that is externally arranged than the inner member is made of a material having a large coefficient of thermal expansion, and these members are temporarily assembled in a heated state, and then cooled. As a result, there is a technique in which the gap becomes small and welding is easily performed. Therefore, for example, by using an amber having a low thermal expansion coefficient for the inner member and using stainless steel (SUS304 or the like) having a melting point close to that of the outer fitting member and a thermal expansion coefficient 17 times larger than this amber, The thickness is small, and the gap between the fitting portions can be reduced.
[0047]
As shown in FIG. 3, the tip lens frame 33 is formed such that the outer peripheral portion 71 of the tip portion has a smaller diameter than other outer peripheral portions. That is, the tip lens frame 33 has a stepped shape. And the inner peripheral part 72 of the front-end | tip part of this front-end | tip lens frame 33 is formed in the small diameter compared with the other inner peripheral part.
[0048]
The tip opening side of the inner peripheral portion 72 of the tip lens frame 33 is a joint surface 73 that is brazed to the tip lens 32, and the brazing material used for brazing wets (flows and forms alloy) into this portion. The thin film part 10 which is surface treatment is provided. In this surface treatment, it is generally desirable that the outermost layer be made of gold. In this embodiment, for example, a nickel intermediate layer is provided between the outermost layer and the stainless steel that is the base material of the tip lens frame 33. The adhesion strength of the outermost layer is improved.
[0049]
A taper surface 74 is formed on the front end side of the joint surface 73 to facilitate the flow of solder during soldering.
[0050]
Next, brazing between the front lens frame 33 and the front lens 32 will be described with reference to FIG.
As shown in the drawing, the tip lens 32 whose outer peripheral surface is metalized 32a is inserted from the tip opening side of the tip lens frame 33 on which the thin film portion 10 is provided. In other words, the tip lens 32 is disposed on the joint surface 73 in the tip lens frame 33, and the outer peripheral surface of the tip lens 32 and the thin film portion 10 and the tapered surface 74 of the tip lens frame 33 are fixed by soldering with solder 77. .
[0051]
During this soldering, the solder does not flow in the area where the thin film portion 10 is not formed. For this reason, the solder flows only within the range where the fitting portion between the front lens 32 and the front lens frame 33 and the surrounding surface treatment are performed. Therefore, stable soldering can be performed by using a certain amount of solder.
[0052]
In addition, when soldering, which is a kind of brazing, it is possible to eliminate problems caused by dirt and corrosion due to residual flux by using a hydrogen furnace solder or vacuum furnace that does not use flux. This is desirable for unit assembly.
[0053]
In soldering, the solder 77 and the metallization 32a on the outer periphery of the tip lens 32 become an alloy, and the solder 77 and the thin film portion 10 of the tip lens frame 33 become an alloy. Depending on the crystallization of this alloy, the flow may be blocked. For this reason, it is necessary to control the crystal state of the alloy by managing the film thickness of the metallization 32a on the outer periphery of the front lens 32 and the thin film portion 10 of the front lens frame 33 as well as the solder component. In this embodiment, since the thin film portion 10 of the front lens frame 33 is formed by PVD as described later, the film thickness can be managed with very high accuracy.
[0054]
Here, a method of forming the thin film portion 10 will be described with reference to FIGS.
The process of forming the thin film portion 10 on the outer peripheral surface of the ceramic frame 35 will be described with reference to FIGS.
[0055]
First, as shown in FIG. 5, a tubular masking member 75a is formed in order to prevent a PVD film portion from being formed in a portion where the solder in the central portion of the ceramic frame 35, which is one of the frame members, should not flow. Only the joint surface 73 is exposed by fitting.
[0056]
The masking member 75 is made of a polymer material such as fluororubber, or a metal sheet such as an aluminum foil. In PVD sputtering and ion plating, the surface treatment has high adhesion even at a temperature lower than that of vacuum deposition. For this reason, a polymer material can be used as the masking member 75, and in this figure, a fluororubber is used.
[0057]
Next, as shown in FIG. 6 (a), at least one ceramic frame 35 on which a masking member 75a is arranged is arranged upright on a jig body 81, which is a jig for the frame, so as to be rotatable. It is arranged on the shaft portion 82 a of the frame body holding member 82. Thereafter, a tubular fixing member 83 formed in the predetermined shape with the same member as the masking member is inserted into the inner hole of the ceramic frame 35, and the through hole of the fixing member 83 is inserted into the shaft portion 82a. . As a result, as shown in FIG. 6B, the ceramic frame 35 is arranged in an upright state on the frame body holding member 82 that is rotatably arranged on the jig main body 81.
[0058]
In addition, a pinion portion 82b having a tooth portion that meshes with a rack portion described later is provided in the middle portion of the frame body holding member 82.
[0059]
Next, as shown in FIGS. 7A and 7B, the jig body 81 is made of a rack portion 84 corresponding to the number of teeth of the pinion portion 82b and a vapor deposition material raw material (for example, nickel) for surface treatment. The target 76 is placed at a predetermined position on the moving mechanism 86 in the sputtering apparatus 85 which is a vapor deposition apparatus.
[0060]
And the said moving mechanism 86 is made into a movement state, and the said jig | tool main body 81 is moved to the arrow B direction intermittently or continuously. Then, when the jig main body 81 is moved, the pinion portion 82b of the frame body holding member 82 rotatably disposed on the jig main body 81 and the rack portion 84 mesh with each other, and the pinion The part 82b is rotated and the frame holding member 82 is rotated in the direction of arrow C. That is, when the jig body 81 is moved by the moving mechanism 86, the pinion portion 82b constituting the rotating means and the rack portion 84 mesh with each other, so that the ceramic frame disposed on the frame body holding member 82 is engaged. 35 rotates.
[0061]
In this way, the jig main body 81 is moved in the sputtering apparatus 85 by the moving mechanism 86, whereby the ceramic frame 35 fixedly arranged on the frame body holding member 82 rotates and the bonding surface faces the target 76. The front surface of the target 76 is moved while changing the position 73.
[0062]
As a result, nickel is deposited on the outer peripheral surface, which is the exposed joint surface 73 of the rotating ceramic frame 35 arranged in an upright state on the frame body holding member 82, and the jig body 81 passes through the target 76. In this case, the thin film portion 10 having a predetermined thickness dimension that forms the bonding surface 73 can be formed on the outer peripheral surface of the ceramic frame 35.
[0063]
Instead of configuring the rotating means by engaging the pinion portion 82b and the rack portion 84, for example, a motor is provided in the shaft body 81 to rotate the ceramic frame 35 disposed on the frame holding member 82. May be.
[0064]
A process of forming the thin film portion 10 on the inner peripheral surface of the tip lens frame 33 will be described with reference to FIGS.
[0065]
First, as shown in FIG. 8, a tubular masking member 75 b and a fixing member that prevent the film portion from PVD from being formed in a predetermined range of the outer peripheral surface and inner peripheral surface of the front end side where the solder of the front end lens frame 33 should not flow. The member / masking member 75c is fitted and arranged so that the joint surface 73 is exposed.
[0066]
Next, as shown in FIG. 9, the tip lens frame 33 in a state where the masking members 75b and 75c are arranged is provided with a height adjusting member 87 on the shaft portion 82a of the frame body holding member 82 arranged on the jig body 81. Through. At this time, the fixing member / masking member 75c and the through hole of the height adjusting member 87 are inserted through the shaft portion 82a. As a result, the tip lens frame 33 is fixedly disposed in an upright state on a frame body holding member 82 that is rotatably disposed on the jig body 81.
[0067]
Next, as shown in FIG. 10, the jig body 81 is disposed on a movable block 91 of an angle adjusting jig 90 that is an inclination angle adjusting means, for example, and an angle adjusting sphere 93 is interposed between the movable block 91 and the fixed block 92. The tip lens frame 33 disposed on the frame body holding member 82 that is rotatably disposed on the jig body 81 is inclined at a predetermined angle.
[0068]
On the other hand, the rack portion 84 corresponding to the number of teeth of the pinion portion 82b is rotated around the shaft portion 84a so as to face the pinion portion 82b of the frame body holding member 82 that is rotatably arranged on the jig body 81. In such a manner, it is adjusted and fixed in a tilted state at a predetermined angle.
[0069]
Then, after the jig body 81 is installed via the angle adjustment jig 90 at a predetermined position on the moving mechanism 86 in the sputtering apparatus 85, the jig body 81 is moved with the moving mechanism 86 in a moving state. . Then, the pinion part 82b and the rack part 84 of the frame body holding member 82 rotatably arranged on the jig body 81 are engaged with each other, and the pinion part 82b is rotated so that the frame body holding member 82 is moved. Rotate and move. In other words, when the jig body 81 tilted by a predetermined angle is moved by the moving mechanism 86, the tip lens frame 33 fixedly arranged on the frame body holding member 82 rotates.
[0070]
As described above, when the tilted jig body 81 is moved by the moving mechanism 86 in the sputtering apparatus 85, the tip lens frame 33 fixedly disposed on the frame body holding member 82 rotates, and the target The entire surface of the target 76 is moved while changing the position of the bonding surface 73 facing the surface 76 in an inclined state.
[0071]
Thus, nickel is deposited on the inner peripheral surface of the distal end side, which is the exposed joint surface 73 of the distal lens frame 33 that is arranged upright on the frame holding member 82 that is inclined at a predetermined angle and rotates, When the jig body 81 passes through the target 76, the thin film portion 10 having a predetermined thickness dimension that forms the bonding surface 73 can be formed on the inner peripheral surface of the tip lens frame 33.
[0072]
In the above-described embodiment, the thin film portion 10 is formed by PVD on the outer peripheral surface of the ceramic frame 35 and the inner peripheral surface of the tip lens frame 33. However, the first pipe 34, the second pipe 36, and the lens are formed. You may make it form the thin film part by PVD10 in the internal peripheral surface etc. of the holder 37. FIG.
[0073]
Further, for example, when a PVD thin film portion is formed on the inner peripheral surface of the lens holder 37, the lens holder 37 is disposed in an inclined state with respect to the target as shown in FIG. 11, and the lens holder 37 is not shown. You may make it rotate with a rotation jig and to provide a thin film part in the internal peripheral surface of this lens holder 37. FIG.
[0074]
The outer peripheral portion 71 on the proximal end side of the lens holder 37 is formed to have a smaller diameter than the other outer peripheral portions, and the inner peripheral portion 72 on the proximal end side of the lens holder 37 is also formed to have a smaller diameter than the other inner peripheral portions. Keep it. The end portion of the inner peripheral portion 72 is a joint surface 73 that is soldered to the rear end lens 39.
[0075]
A tapered surface 74 is formed at the opening of the joint surface 73 to facilitate the flow of solder during soldering. On the other hand, a metal sheet masking 79 such as an aluminum foil is provided so that a thin film portion is not formed in the unsolderable range between the outer peripheral portion 71 and the inner peripheral portion 72 where solder should not flow.
[0076]
Further, as shown in FIG. 12, for example, a cylindrical target attached to the support portion 89 is disposed inside the front lens frame 33, and this target is opposed to the joint surface 73 of the front lens frame 33. You may make it provide a thin film part in the internal peripheral surface of the front-end | tip lens frame 33. FIG. Note that the metal sheet masking is provided in the non-solderable area so that the thin film portion is not formed in the non-solderable area of the inner peripheral portion 72 and other inner peripheral portions.
[0077]
As described above, the front lens frame 33 and the lens holder 37 are provided with a thin film portion by PVD, and the front lens 32 and the rear lens 39 are brazed, and the front lens frame 33, the first pipe 34, the ceramic frame 35, the first By joining the members of the two pipes 36 by brazing, the space surrounded by these members can be made an airtight space where high-pressure steam does not enter at all even if autoclave sterilization is performed.
In addition, the airtight lens unit 30 having high quality stability and hermetically bonded can be supplied at low cost.
[0078]
By these, when autoclave sterilization is performed, the optical system provided inside the frame is prevented from being exposed to water vapor, and the processing accuracy of the brazed part of the parts constituting the frame is improved. Manufacturing cost can be reduced. Further, it is possible to prevent lens fogging due to water vapor intrusion and deterioration of the glass material and coating of the lens, and continuously obtain good images.
[0079]
(Second Embodiment)
FIG. 13 is a cross-sectional view illustrating another configuration of the endoscope imaging apparatus according to the second embodiment of the present invention.
[0080]
As shown in the figure, in the endoscope imaging apparatus 103 according to the present embodiment, the imaging unit includes an airtight lens unit 130, a solid-state imaging device unit 50, a signal cable 61, a lens holder 137, a back cover 63, and heat. A contractible tube 64 is included.
[0081]
That is, in the second hermetic lens unit 130, instead of providing the lens holder 37 and the outer frame 62 shown in the first embodiment, an outer frame integrated with the lens holder 37 and the outer frame 62 integrally formed. A lens holder 137 is used.
[0082]
A back cover 63 is inserted and attached to the base end side of the outer frame integrated lens holder 137. The outer frame integrated lens holder 137 is made of a metal such as stainless steel and has a substantially tubular shape. A surface treatment range 189 is provided at the center in the axial direction of the inner peripheral portion 182, and a PVD thin film is formed in the surface treatment range 189. Is provided. The rear end lens 39 that has been subjected to the metallization process is airtightly bonded to the bonding surface 183 that is a base end side portion of the surface treatment range 189 by brazing. Other configurations are the same as those of the first embodiment, and the same members are denoted by the same reference numerals and description thereof is omitted.
[0083]
Here, when the joint surface 183 of the outer frame integrated lens holder 137 and the metallized outer peripheral surface of the rear end lens 39 are brazed, the outer frame integrated lens holder 137 is heated at a high temperature in order to improve the flowability of the brazing material. Therefore, the outer frame integrated lens holder 137 is thermally expanded. In general, the rear end lens 39 has a smaller coefficient of thermal expansion than the outer frame integrated lens holder 137. For this reason, at the time of brazing, the clearance between the outer peripheral surface of the rear end lens 39 and the inner peripheral surface of the outer frame integrated lens holder 137 increases from that at normal temperature.
[0084]
Thereafter, the brazing material is poured into the gap between the rear end lens 39 and the outer frame integrated lens holder 137 and cooled, so that the brazing material starts to solidify and further cooled to room temperature, so that the brazing portion is completely solid. It becomes.
[0085]
Since the outer frame integrated lens holder 137 contracts from the temperature at which the brazing material starts to solidify to room temperature, the outer peripheral surface of the rear end lens 39 is compressed, but the brazing material is solid. Therefore, only compressive stress is applied.
[0086]
In the outer frame-integrated lens holder 137 having the structure of the present embodiment, the distal end side and the rear end side of the insertion portion have substantially the same length with the rear end lens 39 as the center. For this reason, a constant compressive force is applied to the outer peripheral surface of the rear end lens 39. Therefore, the metallization of the outer peripheral surface of the rear end lens 39 and the surface treatment of the outer frame integrated lens holder 137 can be prevented from peeling off. As a result, a more reliable airtightness can be secured. Other operations are the same as those in the first embodiment.
[0087]
In this way, the outer frame integrated lens holder 137 is configured, and the rear end lens 39 is arranged at substantially the center of the outer frame integrated lens holder 137, so that the metallization processing portion on the outer peripheral surface of the rear end lens 39, It is possible to reliably prevent the surface treatment portion of the frame-integrated lens holder 137 from peeling off. Thereby, the reliability of the endoscope imaging apparatus can be improved.
[0088]
[Appendix]
According to the embodiment of the present invention described in detail above, the following configuration can be obtained.
[0089]
(1) In an endoscope imaging device including a metal lens frame in which an optical member is disposed at least at one end portion or a ceramic ceramic frame disposed by being fitted to a metal metal frame.
A thin film portion having a predetermined thickness for improving solder wettability using physical vapor deposition is provided on the fitting surface of the lens frame with the optical member and the fitting surface of the ceramic frame with the metal frame. Imaging device for endoscope.
[0090]
(2) an arrangement step of arranging the frame member at a predetermined position of the frame jig;
An installation step of installing the frame member arranged in the frame jig in a vapor deposition apparatus having a target;
The frame jig is moved with respect to the target, the frame member arranged on the frame jig is rotated by a predetermined amount along with the movement, and a physical vapor deposition method is applied to the peripheral surface of the frame member. A film part forming step for forming a thin film part;
A method for forming a thin film portion provided in an endoscope imaging apparatus.
[0091]
(3) The thin film portion forming method provided in the endoscope imaging apparatus according to appendix 2, wherein the frame member is disposed in parallel to the target when the thin film portion is formed on the outer peripheral surface of the frame member.
[0092]
(4) When forming the thin film portion on the inner peripheral surface of the frame member, the thin film portion forming method provided in the endoscope imaging apparatus according to appendix 2, wherein the frame member is inclined with respect to the target by a predetermined amount. .
[0093]
(5) The thin film portion forming method provided in the endoscope imaging apparatus according to appendix 2, wherein a thin film portion is formed at a predetermined position of the frame member by providing a masking member on the frame member.
[0094]
(6) The thin film part forming method provided in the endoscope imaging apparatus, wherein the film thickness of the thin film part is set according to the moving time for passing the target of the frame jig.
[0095]
(7) The endoscope imaging apparatus according to appendix 1, wherein when forming the thin film portion on an inner peripheral surface of the frame member, a target is disposed on the inner peripheral surface side of the frame member.
[0096]
【The invention's effect】
As described above, according to the present invention, when autoclave sterilization is performed, the optical member constituting the optical system provided inside the frame is reliably prevented from being exposed to water vapor, and the frame is It is possible to provide an endoscope imaging apparatus capable of improving the processing accuracy of brazing of components to be configured and reducing the manufacturing cost, and a method for forming a thin film portion provided in the endoscope imaging apparatus.
[Brief description of the drawings]
FIG. 1 to FIG. 12 relate to a first embodiment of the present invention, and FIG. 1 is a diagram for explaining the configuration of an endoscope;
FIG. 2 is a cross-sectional view illustrating an endoscope imaging apparatus
FIG. 3 is a diagram for explaining a tip lens frame;
FIG. 4 is a diagram showing a state in which a front lens is joined to a front lens frame.
FIG. 5 is a diagram showing a state in which a masking member is arranged on a ceramic frame.
FIG. 6 is a diagram for explaining the relationship between a ceramic frame on which a masking member is arranged and a jig;
FIG. 7 is a diagram for explaining a process of providing a thin film portion on the outer peripheral surface of a ceramic frame disposed on a jig.
FIG. 8 is a diagram showing a state in which a masking member is arranged on the front lens frame.
FIG. 9 is a diagram for explaining the front lens frame in a state of being arranged on a jig.
FIG. 10 is a view for explaining the positional relationship between the tip lens frame arranged on the jig and the target.
FIG. 11 is a diagram for explaining another method of providing a thin film portion on the inner peripheral surface.
FIG. 12 is a diagram for explaining another method of providing a thin film portion on the inner peripheral surface.
FIG. 13 is a cross-sectional view illustrating another configuration of the endoscope imaging apparatus according to the second embodiment of the present invention.
[Explanation of symbols]
1 ... Endoscope
3 ... Imaging device for endoscope
10. Thin film part
30 ... Airtight lens unit
32 ... tip lens
33 ... tip lens frame
35 ... Ceramic frame

Claims (2)

In an endoscope imaging device comprising a metal lens frame in which an optical member is disposed at least at one end, or a ceramic ceramic frame disposed by being fitted to a metal metal frame,
A thin film portion having a predetermined thickness for improving solder wettability using a physical vapor deposition method is provided on a fitting surface of the lens frame with the optical member and a fitting surface of the ceramic frame with the metal frame. An endoscope imaging device characterized by the above. An arrangement step of arranging the frame member at a predetermined position of the frame jig;
An installation step of installing the frame member arranged in the frame jig in a vapor deposition apparatus having a target;
The frame jig is moved with respect to the target, the frame member arranged on the frame jig is rotated by a predetermined amount along with the movement, and a physical vapor deposition method is applied to the peripheral surface of the frame member. A film part forming step for forming a thin film part;
A method of forming a thin film portion provided in an endoscope imaging apparatus, comprising:

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