JP3863788B2 - Endoscope - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to an endoscope that is provided with an imaging unit in an operation unit and is suitable for reducing the diameter of an insertion unit.
[0002]
[Prior art]
  In recent years, electronic endoscopes incorporating a solid-state image sensor at the distal end of the insertion section are generally used. However, in an endoscope in which the diameter of the insertion section is very thin and a solid-state image sensor cannot be mounted at the distal end of the insertion section, Japanese Patent Laid-Open No. An image guide in which ultrafine glass fibers are bundled is incorporated in the insertion section as shown in 11-151200 and Japanese Patent Laid-Open No. 11-23983, and is transmitted from the image guide to the solid-state imaging device via a projection lens provided in the operation section. There is an endoscope that projects the observed image, converts it into an electrical signal by the solid-state imaging device, and displays it on a monitor via a video processor.
[0003]
  One of the means for sterilizing medical products is autoclave sterilization in which an object to be sterilized is left in a high-pressure and high-temperature steam for a certain period of time, and the need for the endoscope field is high because of low running costs.
[0004]
  An electronic endoscope having a built-in solid-state image sensor at the distal end of the insertion portion in order to give resistance to autoclave sterilization is around an electrical component provided in the operation portion from the objective lens at the distal end of the insertion portion as disclosed in JP-A-10-234649. By covering the inside with a metal cover and hermetically sealing the inside, it is possible to prevent fogging around the lens due to water vapor around the lens, corrosion of the electrical components of the solid-state imaging device, and short circuit.
[0005]
[Problems to be solved by the invention]
  However, as described in JP-A-11-151200 and JP-A-11-23983, the flexibility can be maintained in the conventional insertion portion having flexibility (flexibility). In the case of the structure of an electronic endoscope having a built-in image guide and a projection lens and a solid-state image sensor in the operation unit, the space around the lens and the electrical components of the solid-state image sensor are not hermetically sealed. In addition, when the endoscope is subjected to autoclave sterilization, fogging due to water vapor in the lens, corrosion due to water vapor adhesion in an electrical component, and short circuit may occur.
[0006]
  In Japanese Patent Laid-Open No. 11-234649, a metal inner pipe for hermetic sealing is passed through the insertion portion. Therefore, the insertion portion is rigid and can be used in a laparoscope or a thoracoscope that allows a certain diameter. It is difficult to apply the above structure in a so-called flexible endoscope in which the insertion portion used in the above is required to have thinness and flexibility for insertability.
[0007]
(Object of invention)
  The present invention has been made in view of the above-described points, and provides an endoscope that is resistant to autoclave sterilization without impairing the flexibility (softness) of the insertion portion and capable of reducing the diameter of the insertion portion. The purpose is to do.
[0008]
[Means for Solving the Problems]
  An endoscope according to the present invention includes an objective optical system provided at a distal end of a long and flexible insertion portion that extends from a proximal end of an operation portion, and an image guide that transmits an image incident from the objective optical system. A projection optical system that projects an optical image transmitted by the image guide, a solid-state image sensor that photoelectrically converts the optical image projected by the projection optical system, and an electrical component that is electrically connected to the solid-state image sensor An imaging unit capable of fixing a relative positional relationship between the solid-state imaging device, the projection optical system, and the emission end of the image guide so that an optical image is formed on the solid-state imaging device, and an emission end of the image guide An image guide pipe covering the outer peripheral surface of the image guide, and an image guide holding member having a hole through which the image guide pipe is inserted. The outer peripheral surface of the image guide pipe and the image guide At least a portion of the space formed between the inner peripheral surface of the hole in de holding memberBy airtight sealing by brazingIt is sealed.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
  Embodiments of the present invention will be described below with reference to the drawings.
First, prior to the description of the embodiment of the present invention, an example serving as a reference of the present invention will be described.
(Reference example)
1 to 4 relate to a reference example of the present invention, and FIG.Figure 2 shows the appearance of the endoscope.The endoscopeFIG. 3 shows a schematic configuration of the main part in FIG.In the endoscopeFIG. 4 shows the configuration of the tip.In the endoscopeThe detailed structure of the imaging unit part accommodated in the operation part is shown.
[0010]
  As shown in FIGS. 1 and 2, the endoscope 1 is provided with an elongated and flexible insertion portion 2 to be inserted into a body cavity and the like, and a rear end of the insertion portion 2, and is held by an operator. The operation unit 4 is provided with a grip 3, a universal cord 5 whose base end is extended from the side of the operation unit 4, and a connector unit 6 provided at the distal end of the universal cord 5. The
[0011]
  The insertion portion 2 includes a distal end portion 7 provided at the distal end (distal end), a bending portion 8 provided at the rear end of the distal end portion 7 so as to be bendable, and the operation portion 4 from the rear end of the bending portion 8. The bending portion 8 includes a flexible portion (soft portion) 9 that is long and flexible and reaches a front end of the bending portion 8 by operating a bending operation knob 10 provided in the operation portion 4 via a bending wire (not shown). And can be inserted into a bent body cavity or the like, or the distal end portion 7 can be directed in a desired direction.
[0012]
  As shown in FIG. 2, a light guide 11 that transmits illumination light is inserted into the insertion portion 2, and the light guide 11 is inserted through the operation portion 4 and the universal cord 5 and protrudes at the connector portion 6. When the light guide base 12 is mounted on a light source device (not shown), illumination light is supplied from the light source device to the end surface of the light guide base 12.
[0013]
  Illumination light from the light source device is transmitted by the light guide 11 and emitted from the distal end surface attached to the illumination window portion of the distal end portion 7 via the illumination lens 13 to illuminate a subject such as an affected part in the body cavity.
[0014]
  An optical image of the illuminated subject is formed by an objective lens system 14 that is airtightly attached to an observation window provided adjacent to the illumination window at the tip. The front end surface (incident end surface) of the image guide 15 is fixed at this imaging position. The optical image formed on the front end surface is transmitted to the rear end surface (outgoing end surface) by the image guide 15.
[0015]
  The rear end surface of the image guide 15 is attached to the imaging unit 16 having an airtight structure housed inside the grip portion 3 of the operation unit 4, and the optical image transmitted to the rear end surface is a projection lens system as a relay optical system. A (imaging lens system) 17 projects (images) onto a solid-state imaging device, for example, a charge imaging device (abbreviated as CCD) 18.
[0016]
  The CCD 18 is connected to a circuit board 19 as an electrical component disposed on the back side thereof, and the circuit board 19 is connected to a signal cable 21 via a hermetic connector 20. The signal cable 21 is inserted through the universal cord 5 and connected to the electrical connector 22 of the connector portion 6.
[0017]
  As will be described later with reference to FIG. 4, the imaging unit 16 has an airtight structure inside and can be sterilized by autoclave.
[0018]
  The electrical connector 22 is connected to a video processor as a video signal processing device via a connection cable (not shown), and an imaging signal photoelectrically converted by the CCD 18 is read by a drive signal from the video processor. It is converted into a video signal by an internal video processing circuit and output to a monitor (not shown) so that an image captured by the CCD 18 is displayed as an endoscopic image on the display surface of the monitor.
[0019]
  FIG. 3 shows the structure near the objective lens system 14 at the tip 7.
  The distal end portion 7 is formed of a substantially cylindrical metal by the distal end portion main body 24, and the objective lens system 14 is hermetically attached to an observation window portion (a hole forming) provided in the axial direction of the distal end portion main body 24. In addition, the tip of the image guide 15 is hermetically fixed to the imaging position on the optical axis via a metal pipe 25a.
[0020]
  The image guide 15 is composed of a bundle of a large number of ultrafine glass fibers 15a, and metal pipes 25a and 25b are attached to both ends of the front end and rear end (see FIG. 4) so as to cover the outer periphery. The pipes 25a and 25b protect the inside. In addition, the outer periphery of the bundle of glass fibers 15a between the image guides 15 excluding both ends is covered with a soft tube 26 made of a soft silicon resin or the like.
[0021]
  The objective lens system 14 includes, for example, a front lens group 27a composed of two lenses and a rear lens 27b composed of one lens. The front lens group 27a vapor-deposits metal on its outer peripheral surface, and inserts the fitting portion into the hole of the observation window portion of the tip end body 24 and brazes the fitting portion (metal vapor deposition portion) to the inner peripheral surface of the hole. And airtight joining.
[0022]
  Similarly, the rear lens 27b is vapor-deposited on the outer peripheral surface and brazed to the inner peripheral surface of the pipe 25a to be hermetically bonded.
[0023]
  Further, the metal fiber is deposited on the outer peripheral surface of the tip portion of the glass fiber 15a, and then brazed to the pipe 25a to be hermetically joined.
  Further, the pipe 25a and the tip end body 24 (the hole in the observation window) are also airtightly joined by brazing.
[0024]
  In this way, even when autoclave sterilization is performed in high-pressure and high-temperature steam, the imaging function prevents the steam from entering the space 28 inside the objective lens system 14 (the cloudiness that occurs when it enters). It has an airtight structure that can prevent deterioration.
[0025]
  The most advanced joint piece 29 forming the curved portion 8 is fixed to the rear end of the distal end main body 24 by brazing or the like, and the rear end joint piece 29 is rotatably connected by a rivet or the like. The bending portion 8 is formed by the joint piece 29 (see FIG. 2).
  Further, as shown in FIG. 3, the outer periphery of the joint piece 29 is covered with a rubber tube 30 serving as a soft exterior member.
[0026]
  FIG. 4 shows the imaging unit 16 provided inside the grip 3. The imaging unit 16 projects an optical image (endoscopic observation image) transmitted to the emission end face (rear end face) by the image guide 15 onto the CCD 18 by the projection lens system 17 and converts it into an electrical signal. Therefore, it can also be said to be an image guide CCD connection unit.
[0027]
  The rear end portion of the image guide 15 is covered with the metal pipe 25b as described above, and this pipe 25b portion is inserted into a hole formed at the center of the image guide holding member 32 and is airtightly joined. On the axial extension of the image guide 15, a projection lens frame 33 in which the projection lens system 17 is housed and fixed so as to form a projection image in which the observation image is appropriately focused is provided via the projection lens holding member 34. To be airtightly fixed.
[0028]
  Further, a CCD holding member 35 that houses the CCD 18 on its axial extension is hermetically connected to the projection lens frame 33 at a focus position where the observation image projected by the projection lens system 17 on the imaging surface of the CCD 18 is focused. Yes.
[0029]
  Further, the rear side from the vicinity of the outer periphery of the CCD 18 is covered with a metal-made cylindrical shield member 36. A circuit board 19 such as a printed circuit board disposed on the back side of the CCD 18 is accommodated inside the CCD 18 while being connected to the CCD 18, and a plurality of conductive pins 37 are provided on the rear side of the circuit board 19. The hermetic connector 20 is provided so as to be insulated from each other and hermetically maintained, and the outer peripheral surface of the hermetic connector 20 is hermetically fixed to the shield member 36.
[0030]
  This hermetic connector 20 is inserted through a plurality of holes in a disk-shaped metal member so as to penetrate each conductive pin 37, and a glass sealing member as an airtight insulating means around the conductive pin 37 in each hole. 38, the inner end of each conductive pin 37 in this hermetic connector 20 is connected to the circuit board 19 by a lead wire or the like, and the outer end is connected to the signal cable 21. Are connected to a plurality of signal lines 39 extending from.
[0031]
  The signal cable 21 is connected to an electrical connector 22 (see FIG. 2) through the operation unit 4, the universal cord 5, and the connector unit 6. As described above, the electrical signal of the observation image can be transmitted to the video processor by connecting to the video processor via a connection cable (not shown).
[0032]
  Incidentally, since the image guide 15 itself is resistant to autoclaving, a structure for hermetically sealing the outer periphery of the image guide 15 passing through the insertion portion 2 with a metal pipe is not necessary.
[0033]
  Here, the connection method of each member will be described. The outer periphery of the rear end portion (rear end portion of the glass fiber 15a) of the image guide 15 is subjected to metal vapor deposition and brazed to the pipe 25b to be hermetically joined. Yes. The fitting portion of the pipe 25b and the image guide holding member 32 is hermetically joined by brazing.
[0034]
  Further, the projection lens holding member 34 and the image guide holding member 32, the projection lens holding member 34 and the projection lens frame 33, the projection lens frame 33 and the CCD holding member 35, the CCD holding member 35 and the shield member 36, the hermetic connector 20 and the shield member. 36 is hermetically sealed by laser welding (laser welding portions 40 ', 41', 42 ', 43', 44 ') at each fitting portion (fitting portions 40, 41, 42, 43, 44 in FIG. 4). It is joined.
[0035]
  Also in the illumination lens 13, for example, when there is a gap between the distal end surface of the light guide 11 and the illumination lens 13, the objective lens system 14 and the distal end portion of the image guide 15 are made airtight. As in the case of airtight structure.
[0036]
  Each member constituting the endoscope 1 is made of a material having a characteristic capable of withstanding the temperature at the time of autoclave sterilization.
[0037]
  nextReference exampleThe action when sterilizing mainly in an autoclave will be described. Since the insertion section 2 is thin, the endoscope 1 can be used without causing great pain to the patient even when examining the bronchi.
[0038]
  It is necessary to sterilize the endoscope 1 before performing an endoscopic examination. The endoscope 1 is put into an autoclave sterilizer, and the endoscope 1 is sterilized by autoclave, that is, high-temperature and high-pressure steam. Expose to the environment for a specified time.
[0039]
  In this case, the steam penetrates through the exterior member such as the rubber tube 30 of the endoscope 1. In this case, since the internal space 28 of the objective lens system 14 has an airtight structure, it is possible to prevent vapor from entering the space 28.
[0040]
  Even if steam penetrates the flexible tube 26, the image guide 15 is resistant to the autoclave atmosphere, so there is no problem. The same applies to the light guide.
[0041]
  Even if the vapor penetrates the exterior member of the operation unit 4, the imaging unit 16 has an airtight structure inside as described above, so that it projects onto the rear end surface of the image guide 15 as shown in FIG. A space 45 between the lens system 17, a space 46 inside the projection lens system 17, a space 47 between the rear end of the projection lens system 17 and the CCD 18, and a space 48 inside the shield member 36 can be kept airtight.
  Therefore, it is possible to prevent the imaging function from being deteriorated due to fogging when the vapor enters, and the circuit components from being deteriorated in characteristics by the vapor.
[0042]
  As explained above,Reference exampleAccording to the above, a space 28 between the front lens group 27a and the rear lens 27b, a space 45 between the rear end of the image guide 15 and the projection lens system 17, a space 46 inside the projection lens system 17, and a projection lens. The space 47 between the rear end of the system 17 and the CCD 18 and the space 48 inside the shield member 36 can be kept airtight.
[0043]
  Therefore,Reference exampleHas the following effects.
  Reference exampleAccording to the above, it is possible to prevent the vapor from entering the spaces 28, 45 and the like even when exposed to an environment of high pressure and high temperature steam such as autoclave sterilization without impairing the flexibility and thinness of the insertion portion 2. Further, the endoscope 1 can be provided which can be repeatedly subjected to endoscopic inspection by autoclave sterilization without causing fogging of the lens and the like, and without corroding or short-circuiting the electric parts.
[0044]
Next, an embodiment of the present invention will be described.
(Embodiment of the present invention)
Next, an embodiment of the present invention will be described with reference to FIG. This embodiment isIn the endoscope 1 shown in FIG. 2, an imaging unit unit (image guide CCD connection unit unit) 16B having a structure shown in FIG.
[0045]
  That is, the imaging unit 16B projects the optical image transmitted to the emission end of the image guide 15 onto the CCD 18 by the projection lens system 17 (receives an optical image by the objective lens system 14 provided at the tip 7 at the incident end). However, it is converted into an electric signal.
[0046]
  This embodiment isReference exampleIn the image pickup unit section 16 in FIG. 1, instead of the image guide holding member 32, an image guide holding member 51 having a structure in which the inner diameter is made larger and the image guide 15 can be adjusted and fixed is adopted. A portion from the front end of the holding member 51 to the hermetic connector 20 is hermetically covered with a metal cover 52 (which can be hermetically covered). Hereinafter, the configuration will be described in more detail. In addition,Reference exampleThe same components as those in FIG.
[0047]
  The image guide 15 is held by the image guide holding member 51 at a metal pipe 25b portion provided at the rear end thereof. The image guide holding member 51 has three screw holes (3 in the circumferential direction) in which a screw 53 for adjusting the center position of the axis of the image guide 15 and a screw 54 for adjusting the inclination of the image guide 15 are respectively attached. Equally) position. The image guide 15 is held by the screws 53 and 54.
[0048]
  Further, a hole 55 penetrating the image guide holding member 51 is provided in a portion between the screws 53 and 54 in the image guide holding member 51 so as to communicate with the outer peripheral surface of the pipe 25b disposed inside thereof. .
  Further, the projection lens frame 33 to which the projection lens system 17 is attached on the extension of the axis of the image guide 15 holds the projection lens at a position where the optical image transmitted to the rear end surface of the image guide 15 can be projected in a focused state. It is fixed via a member 56.
[0049]
  Three holes 57 are formed in the projection lens holding member 56 so that the projection lens holding member 56 and the image guide holding member 51 are connected to the screws 53 and 54 and the holes 55 of the image guide holding member 51. Yes.
[0050]
  A CCD holding member 35 holding the CCD 18 is fixed at a projection position on the optical axis of the projection lens system 17 in the projection lens frame 33, and a circuit board 19 and a hermetic connector 20 are arranged on the back side thereof. The outer peripheral sides of the CCD 18 and the circuit board 19 are covered with a shield member 36 made of a metal member for blocking radio waves.
[0051]
  A cover 52 made of a metal member covers substantially the whole of the imaging unit unit 16B so as to cover a portion from the vicinity of the front end of the image guide holding member 51 to the outer peripheral surface of the hermetic connector 20 which is the rear end of the imaging unit unit 16B. Is provided. When each connection method in this case is described, the glass fiber 15a and the pipe 25b are airtightly joined by brazing.
[0052]
  The pipe 25b and the image guide holding member 51 are adjusted with the screws 53 and 54 to adjust the core and inclination of the glass fiber 15a, and then flow the wax through the holes 57 and 55, so that the pipe 25b and the image guide holding member 51 The wax 58 is filled in the gap with the inner peripheral surface of the image guide holding member 51, and the rear side of the wax 58 is cut off from the outside and airtightly joined. The screw hole to which the screw 54 on the front side of the hole 55 is attached is such that the image guide 15 is adjusted and fixed with the screw 54, and then the wax 58 is poured from the hole 57 to the top (upper end) so as to be sealed watertight. I have to.
[0053]
  Further, the cover 52 and the image guide holding member 51, and the cover 52 and the hermetic connector 20 are fitted to each other (fitting portions 61 and 62) by laser welding to form laser welding portions 61 'and 62'. It is joined.
[0054]
  Also, inside the cover 52,Reference exampleThen, the portion hermetically joined by laser welding is fixed with an adhesive.
[0055]
  That is, the image guide holding member 51 and the projection lens holding member 56, the projection lens frame 33 and the projection lens holding member 56, the projection lens frame 33 and the CCD holding member 35, the fitting portions 40 of the CCD holding member 35 and the shield member 36, 41, 42 and 43 are fixed with an adhesive.
[0056]
  The operation when the autoclave sterilization process of the present embodiment is performed will be described. When autoclaved,Reference exampleAs described above, if the vapor penetrates the exterior member of the operation unit and the vapor enters the inside, the imaging unit unit 16B is exposed to the vapor.
[0057]
  In this case, the entire outer peripheral surface of the imaging unit section 16B is hermetically covered with the cover 52 except for the vicinity of the fixed portion of the image guide 15 at the front end and the rear end of the imaging unit section 16B.
  Further, the front end of the cover 52 is held airtight by the laser welded portion 61 ′ of the fitting portion 61, and the rear end is held airtight by the laser welded portion 62 ′ of the fitting portion 62.
[0058]
  Further, the pipe 25b portion of the rear end surface of the image guide 15 in the image pickup unit section 16B is hermetically sealed with the image guide holding member 51 by the wax 58, so that the rear side of the image guide 15 on the rear end side with respect to the wax 58 portion. It is possible to prevent the vapor from entering the space on the end face side. Further, since the screw hole provided on the front side of the outer peripheral position of the pipe portion 25b and to which the screw 54 is attached is hermetically sealed with the wax 58, it is possible to prevent vapor from entering the inside of the cover 52 from the screw hole. Can be prevented.
[0059]
  Further, since the rear end face of the imaging unit 16B is hermetically sealed with the hermetic connector 20, it is possible to prevent vapor from entering the space inside this part.
[0060]
  Therefore, this embodiment has the following effects.
  This embodiment isReference exampleIn addition to providing the above-described effects, a function for adjusting the fixed position of the rear end (outgoing end) of the image guide 15 is further provided, so that accurate image adjustment can be performed.
[0061]
  In FIG. 5, an airtight sealing hole 55 is provided between the screws 53 and 54 in the image guide holding member 51, but a position further forward than the screws 54 (that is, both screws 53 and 54). As shown in the modified example of FIG. 6 in which a hole 55 for hermetic sealing is provided, a wax 58 is poured into the hole 55 so that a gap between the outer peripheral surface of the pipe 25b and the inner peripheral surface of the image guide holding member 51 is provided. The wax 58 may be airtight.
  In this case, it is not necessary to hermetically seal the screw hole of the screw 54 with the wax 58 as shown in FIG. Other configurations are the same as those in FIG.
[0062]
  In addition,Reference exampleIn FIG. 5, a lateral hole (corresponding to the hole 55 in FIG. 5) that communicates with the fitting hole from the outer periphery, for example, near the center of the fitting hole portion that is inserted so that the pipe 25 b of the image guide holding member 32 is fitted. While being provided, the diameter of the fitting hole portion of the portion may be increased, and the wax may be poured from the lateral hole so that the inside thereof can be filled and airtight.
[0063]
[Appendix]
1. A long insertion portion made of a flexible material;
  An operation unit connected to a base end of the insertion unit;
  An objective optical system that is provided at the distal end of the insertion section and acquires an optical image of the subject;
  An image guide fiber bundle having flexibility to transmit the optical image inserted through the entire length of the insertion portion and emitted from the objective optical system;
  An image guide holding member formed of a cylindrical metal material for holding a base end portion of the image guide fiber bundle;
  A projection optical system that is provided in the operation unit and projects the optical image emitted from the base end face of the image guide fiber bundle;
  A projection optical system holding member formed of a cylindrical metal member that holds the projection optical system inside;
  An image sensor that captures an optical image projected by the projection optical system;
  An image sensor holding member formed of a cylindrical metal member that holds the image sensor inside;
  A board on which electronic components that are electrically connected to the image sensor and process electrical signals output from the image sensor are mounted;
  A cylindrical metal that is connected to the imaging element holding member in an airtight state at its distal end and whose base end is sealed in an airtight state with an insulating sealing material, and accommodates the substrate inside A substrate housing member formed of a material;
  A first hermetic connection portion provided at a distal end portion of the insertion portion and connecting the objective optical system and the distal end portion of the image guide fiber bundle in an airtight state;
  A second hermetic connection portion provided on the projection optical system holding member and connecting the image guide holding member to the projection optical system holding member in an airtight state;
  A third hermetic connection provided on the projection optical system holding member to connect the projection optical system holding member and the image sensor holding member in an airtight state;
  An endoscope characterized by comprising:
[0064]
2. The second and third hermetic connection means are first and second fitting portions formed by fitting the image guide holding member and the image sensor holding member to the projection optical system holding member, respectively. The endoscope according to appendix 1, wherein the endoscope includes first and second welded portions formed by welding the first and second fitting portions, respectively.
[0065]
3. A long insertion portion made of a flexible material;
  An operation unit connected to a base end of the insertion unit;
  An objective optical system that is provided at the distal end of the insertion section and acquires an optical image of the subject;
  An image guide fiber bundle having flexibility to transmit the optical image inserted through the entire length of the insertion portion and emitted from the objective optical system;
  An image guide holding member formed of a cylindrical metal material for holding a base end portion of the image guide fiber bundle;
  A projection optical system that is provided in the operation unit and projects the optical image emitted from the base end face of the image guide fiber bundle;
  A projection optical system holding member formed of a cylindrical metal material that holds the projection optical system inside;
  An image sensor that captures the optical image emitted from the base end face of the projection optical system;
  An image sensor holding member formed of a cylindrical metal material that holds the image sensor inside;
  A board on which electronic components that are electrically connected to the image sensor and process electrical signals output from the image sensor are mounted;
  A substrate housing member formed of a cylindrical metal material whose base end portion is sealed with an insulating sealing material and accommodates the substrate;
  First airtight connection means for connecting the objective optical system and the image guide fiber bundle in an airtight state at a distal end portion of the insertion portion;
  A second airtight connection formed of a cylindrical metal material that houses the relay optical system holding member and the imaging element holding member inside and connects the image guide holding member and the substrate housing member in an airtight state. Means,
  An endoscope characterized by comprising.
[0066]
  [Supplementary Note 4] The supplementary note 2 is characterized in that the image guide holding member includes an adjustment unit that can adjust a distance between a proximal end surface of the image guide fiber bundle and a distal end surface of the projection optical system. Endoscope.
[0067]
【The invention's effect】
  As described above, according to the present invention, the insertion portion can be made to have a small diameter, and the structure does not impair the flexibility. Even if autoclave sterilization is performed, water vapor does not enter the space around the lens and the electrical equipment portion. It is possible to realize an endoscope that can prevent the occurrence of fogging, corrosion, and the like due to.
[Brief description of the drawings]
FIG. 1 of the present inventionReference exampleThe external view of an endoscope.
[Figure 2]Reference exampleFIG. 2 is an overall view showing a schematic configuration of a main part in an endoscope.
[Fig. 3]In a reference endoscopeSectional drawing which shows the structure of the front-end | tip part of an insertion part.
[Fig. 4]In a reference endoscopeSectional drawing which shows the detailed structure of the imaging unit part accommodated in the operation part.
FIG. 5 shows the present invention.EmbodimentSectional drawing which shows the detailed structure of the imaging unit part in FIG.
[Fig. 6]Embodiment of the present inventionSectional drawing which shows the structure of the principal part of the imaging unit part in the modification of this.
[Explanation of symbols]
  1 ... Endoscope
  2 ... Insertion section
  3 ... gripping part
  4 ... Operation part
  5. Universal code
  6 ... Connector
  7 ... Tip
  8: Curved part
  11 ... Light guide
  13 ... Lighting lens
  14 ... Objective lens system
  15. Image guide
  15a ... glass fiber
  16. Image pickup unit (image guide CCD connection unit)
  17 Projection lens system
  18 ... CCD
  19 ... Circuit board
  20 ... Hermetic connector
  21 ... Signal cable
  24 ... tip body
  25a, 25b ... pipe
  32. Image guide holding member
  33 ... Projection lens frame
  34 ... Projection lens holding member
  35 ... CCD holding member
  36 ... Shielding member
  40'-44 '... Laser weld

Claims (3)

An objective optical system provided at the distal end of the long and flexible insertion portion extending from the proximal end of the operation portion;
An image guide for transmitting an image incident from the objective optical system;
A projection optical system for projecting the optical image transmitted by the image guide;
A solid-state imaging device that photoelectrically converts an optical image projected by the projection optical system;
An electrical component electrically connected to the solid-state imaging device;
An imaging unit capable of fixing a relative positional relationship between a solid-state imaging device, a projection optical system, and an emission end of an image guide so that an optical image is formed on the solid-state imaging device;
An image guide pipe covering the outer peripheral surface of the output end side of the image guide;
An image guide holding member formed with a hole through which the image guide pipe is inserted;
With
At least a part of a space formed between an outer peripheral surface of the image guide pipe and an inner peripheral surface of a hole in the image guide holding member is sealed by airtight sealing by brazing . Endoscope. 2. The brazing injection hole for brazing is formed in the image guide holding portion so as to communicate the outer peripheral surface of the image guide holding member and the space. Endoscope.   The image guide holding portion is formed with at least three adjustment holes for communicating with the outer peripheral surface of the image guide holding member and the space and engaging with screws for adjusting the central axis position of the image guide. The endoscope according to claim 1 or 2, wherein the endoscope is formed.

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