JP2005074035A - Imaging unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging unit including a flexible board with high reliability, which is hardly affected by an outer force or a vibration. <P>SOLUTION: A plurality of electronic components are mounted on one surface 5a of the imaging unit which has the double-sided flexible board 5 where connection parts to connect the core wire 61a of a cable, or the like, are arranged on the other surface 5b. The connection parts are lands for connection 11, 12, 13, 14 which are arranged on the other surface 5b of the double-sided flexible board 5, and the lands for connection are arranged at least to be mutually put over each other on the rear surface part opposing the two electronic components 3, 7, and the like, which are mounted in a longitudinal direction on one surface 5a of the board 5. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an imaging device, and more particularly to an imaging device including a double-sided flexible substrate.

  In recent years, the external shape of a solid-state imaging device such as a CCD or C-MOS has been demanded for downsizing of an imaging apparatus itself to which these solid-state imaging devices are applied, and the progress of downsizing of the external shape of the device has been remarkable. Further, the downsizing of the imaging device itself is not limited to the downsizing of the solid-state imaging device, but also electronic components such as a driving circuit for the solid-state imaging device, an electric board (mostly a flexible board) on which these electronic components are mounted, and a wiring material. This has spread to downsizing (thinning of diameter) and reduction of the number of parts.

  Such enthusiasm for downsizing of the imaging device is no exception in the field of endoscope devices, and progress in downsizing of the imaging device in the endoscope device is also remarkable.

  On the other hand, in an endoscope apparatus, there is a desire for a reduction in size and diameter of the outer shape of the insertion portion.

  In the field of endoscope devices under such circumstances, in order to reduce the outer diameter of the insertion portion and to reduce the size of the imaging device, along with the adoption of a small solid-state imaging device, the axial direction (longitudinal direction of the insertion portion) An imaging device for an endoscope in which an electric circuit board (substrate for driving a solid-state imaging device) formed so as to be relatively long is also known.

  Note that a flexible substrate is mainly employed as the electric circuit board disposed in the endoscope insertion portion.

  As described above, by using an electric circuit board (flexible substrate) formed so as to be relatively long in the axial direction (longitudinal direction) of the insertion portion, it is easy to reduce the diameter of the insertion portion. The strength of the electric substrate alone tends to decrease. That is, as described above, the flexible circuit board is mainly used as the electric circuit board disposed in the endoscope insertion portion. However, the electric circuit board is originally formed of a material that is easily bent by an external force and vibration. In addition, the longer the substrate is in the longitudinal direction, the lower the bending strength of the substrate itself is.

  The influence of the above decrease in bending strength increases the risk of peeling of mounted components (mainly chip components) and contact between mounted components due to unexpected external forces and vibrations during manufacturing, and is a reliable circuit board. It will lead to a decrease in performance.

  The present invention has been made in view of such circumstances, and an object thereof is to provide an imaging apparatus including a highly reliable flexible substrate that is not easily affected by external force or vibration.

  The first imaging device of the present invention is an imaging device having a double-sided flexible board in which a plurality of electronic components are mounted on one surface side and a connection portion for connecting a core wire of a cable is disposed on the other surface side. A connection land disposed on the other surface side of the double-sided flexible substrate, and facing at least two electronic components mounted on the other surface side of the double-sided flexible substrate in the longitudinal direction of at least one surface of the substrate. It is a land for connection arranged so as to straddle the back surface part.

  The second imaging device of the present invention is characterized in that, in the first imaging device, the connection portion is a connection land for connecting the core wires of the cable with solder.

  According to the present invention, it is possible to provide an imaging device including an electrical circuit board that is not easily affected by external force or vibration and has high reliability.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a cross-sectional view showing a longitudinal section of a distal end portion of an imaging apparatus including an embodiment of the present invention. FIG. 2 shows a flexible substrate (hereinafter referred to as FPC) installed in the imaging apparatus. It is the top view seen from the back side, and also has seen through the component mounting surface of this board | substrate.
In this embodiment and other examples described later, the optical axis O indicates the optical axis of the imaging optical system. Further, the subject side direction of the optical axis O direction in the imaging apparatus is defined as the front, and the imaging element side or the cable insertion side is defined as the rear.

  An imaging apparatus 1 shown in FIG. 1 includes an imaging optical system 20 disposed at the distal end portion of the insertion portion, a solid-state imaging apparatus 2 disposed behind the imaging optical system 20, and a solid state in the solid-state imaging apparatus 2. An FPC 5 that is a circuit board for driving control of the image sensor 3, a plurality of electronic components (indicated by reference numerals 7 to 10 in FIG. 1) mounted on one surface side (front surface side) of the FPC 5, and the FPC 5 And a cable bundle 6 for supplying power, signals and the like to each electronic component.

  The imaging optical system 20 includes a first lens 34, a diaphragm (brightness diaphragm) 35, and a second lens in order from the subject side as an optical member that is bonded and fixed to the inner peripheral portion of a lens frame (objective lens holding frame) 31. 36, a flare prevention plate 32, and a third lens 37, and the third lens 37 is held with respect to the lens frame 31 in the optical axis O direction via a spacing tube 33. The imaging optical system 20 is fitted and supported inside the imaging element holding frame 24 via a lens frame 31.

  The solid-state imaging device 2 includes a solid-state imaging device 3 and a cover glass 4 that is bonded and fixed so as to cover the light receiving surface of the solid-state imaging device 3. The solid-state imaging device 2 is bonded and fixed to the rear of the imaging element holding frame 24 via a flare prevention plate 25.

  Further, the solid-state imaging device 3 is provided with a connecting portion 3a that is connected to an inner lead 5c extending from one end of the FPC 5, and when the solid-state imaging device 2 is incorporated into the imaging device 1, the inner lead 5c An adhesive is applied between the bottom surface side of the solid-state image pickup device 3 and the FPC 5 including the bump-connected portion, and the solid-state image pickup device 3 is placed on one surface side of the FPC 5. It is mounted by adhesive fixing.

  A surface on which the solid-state imaging device 3 is mounted on the FPC 5 in a state where the inner lead 5c is bump-connected to the connection portion 3a is defined as one surface side (front surface side) of the FPC 5.

  The FPC 5 is a double-sided mounting FPC (double-sided mounting flexible substrate) on which a circuit or the like used for driving control of the solid-state imaging device 3 is mounted, and on one surface side (surface side) 5a, in addition to the solid-state imaging device 3, The electronic components for the drive control circuit of the solid-state image sensor 3 are mounted, and cables 61 to 64 and the like provided in the cable bundle 6 are connected to the other surface side (back surface side) 5b. The cable bundle 6 includes a plurality of cables 61 to 64. These cables 61 to 64 supply power to the drive control circuit on the FPC 5, input / output control signals of the circuit, and solid-state imaging. This is a cable for outputting an imaging signal from the element 3.

  As shown in FIGS. 1 and 2, on one side 5 a of the FPC 5, the chip capacitor 7, the chip capacitor 8, the chip resistor 9, and the chip transistor 10 in addition to the above-described solid-state imaging device 3 are approximately in the longitudinal direction of the FPC 5. Implemented in series. As described above, in this embodiment, the electronic component mounted on the FPC 5 is constituted by a so-called chip component as described above. Chip components are suitable for configuring small discrete circuits, but they may be peeled off against warping beyond the tolerance applied to the board, and consideration must be given to the bending strength, shape design, and arrangement method of the board. is there.

  Returning to FIG. 2, on the other side (back side) 5b of the FPC 5, there are connecting lands 11, 12, 13, and 14 for soldering the tip end cores of the cables 61, 62, 63, and 64, respectively. It is arranged.

  The connection land 11 includes a back surface portion of the FPC 5 facing the solid-state image sensor 3 (portion indicated by a broken line 3 in FIG. 2) and a back surface portion of the FPC 5 facing the chip capacitor 7 (similarly, in FIG. (Part indicated by a broken line).

  Similarly, the connection land 12 includes a back surface portion of the FPC 5 facing the chip capacitor 7 (a portion indicated by a broken line 7 in FIG. 2) and a back surface portion of the FPC 5 facing the chip capacitor 8 (a broken line 8 in FIG. 2). It is arranged so as to straddle the portion indicated by. The connection land 13 includes a back surface portion of the FPC 5 facing the chip capacitor 8 (a portion indicated by a broken line 8 in FIG. 2) and a back surface portion of the FPC 5 facing the chip resistor 9 (a portion indicated by a broken line 9 in FIG. 2). ). The connection land 14 includes a back surface portion of the FPC 5 facing the chip resistor 9 (a portion indicated by a broken line 9 in FIG. 2) and a back surface portion of the FPC 5 facing the chip transistor 10 (a portion indicated by a broken line 10 in FIG. 2). ).

  Further, the core wire 61a of the tip end of the cable 61 is connected to the connection land 11 by soldering. Similarly, the tip end core wires 62a, 63a and 64a of the cables 62, 63 and 64 are soldered to the connection lands 12, 13 and 14, respectively.

  As described above, in the present embodiment, on the back side of the FPC 5, the connection land is provided so as to straddle the portion corresponding to the back side of the chip component adjacent in the longitudinal direction mounted on the front side of the FPC 5. A cable core wire having a relatively large shape compared to the size of these chip parts is connected to the connection land by solder. As described above, the cable core wire is connected to the connection land with solder and is hardened, so that the strength around the connection land portion is increased, and the bending strength between the chip components in the FPC 5 is greatly increased. .

  As described above, in an FPC on which chip components are mounted, there is a risk of peeling of the components if the substrate warps more than allowable, but in this embodiment, the bending strength between the chip components is dramatically increased. Therefore, even when force is applied to the FPC 5 due to unexpected external force or vibration at the time of assembling the imaging device 1, for example, bending of the substrate around the chip component can be prevented and peeling of the component can be prevented. . Further, contact and short-circuit between chip parts are prevented, and the outer shape at the time of completion is stabilized, so that an imaging device including an extremely reliable FPC 5 can be provided.

  In this embodiment, the strength of the periphery of the connection land 11 is increased by soldering the core wire 61a of the cable 61 to the connection land 11 or the like, but the cable 61 is not connected. In this case, by arranging the connection lands having the increased bending strength of the land portion itself, the bending strength of the FPC 5 itself can be increased, although it is inferior to that when the cable 61 is connected. For example, by forming the connecting lands 11 etc. with a thick conductor foil or plating with respect to the FPC 5, the bending strength of the lands can be increased, and the surroundings can be obtained even when the cable is not connected. The chip member can be prevented from being peeled off.

  Further, the technical idea relating to the configuration of the FPC 5 in the imaging apparatus 1 of the present embodiment can be applied to the FPC in any imaging apparatus 1 and is useful not only in the endoscope field but also in FPCs in imaging apparatuses that are particularly desired to be downsized. is there.

  On the other hand, in the FPC 5 of the present embodiment, the electrode 7a of the chip capacitor 7 and the electrode 8a of the chip capacitor 8 are laid out so as not to overlap the connection lands 11 to 13 on the back surface side.

  Such a layout can make it difficult for heat generated when the cable 61 or the like is solder-connected to the connecting lands 11 to 13 to the chip capacitor 7 or 8, and the chip capacitor is peeled off by this heat. Such a risk can be reduced.

  On the other hand, the connection land 13 is disposed so as to occupy a larger area than the other connection lands 11 and the like, and is laid out so as to partially overlap the back surface side of the electrode 10 a of the chip transistor 10. Yes. A core wire 64 a of a cable 64 having a relatively large core wire is connected to the connection land 13. Since the chip transistor 10 is a chip member of a transistor that generates a relatively large amount of heat as compared with other passive elements, the heat generated in the chip transistor 10 during driving of the imaging device 1 is efficiently connected to the connection land 13 and the cable 64. And the temperature rise of the chip transistor 10 can be suppressed, and the chip transistor 10 can be operated stably. Further, as the transistor chip is miniaturized, the temperature rises sharply, but this temperature rise can be suppressed and the characteristics of the transistor can be improved.

  By the way, in a conventional imaging apparatus using a CCD (solid-state imaging device), a TAB-mounted CCD is usually applied. When the CCD is mounted on the imaging apparatus, the CCD is incorporated, inspected, and connected to the CCD. A cable soldering operation or the like is performed on the electric board. During these operations, the CCD connection electric board is often disconnected from the connection portion for holding each connection land at the same potential, and the cable land is often in an open state.

  In the above conventional imaging apparatus, when the cable connection work is performed, the cable land of the electric board to which the CCD is connected is in an open state. There was a possibility of electrostatic breakdown during the attaching process. In particular, when the CCD is downsized, the resistance to static electricity is also reduced, so that the possibility of electrostatic breakdown is further increased.

  The image pickup apparatus 1 shown in FIG. 1 solves the above-described conventional problems, and measures for preventing electrostatic breakdown are taken in order to prevent the occurrence of electrostatic breakdown when the solid-state image sensor is incorporated into the image pickup apparatus.

  The FPC 5 before connection of the cable shown in FIGS. 1 and 2 is in a state in which the connection portion 15 (FIG. 3) for maintaining the same potential for inspection or for the land portion or the like is disconnected. Therefore, the connection lands 11, 12, 13, and 14 of the FPC 5 are in an electrically open state. If the above-described soldering operation or adjustment operation of the cables 61, 62, 63, and 64 is performed in that state, the solid-state imaging device 3 may be electrostatically damaged due to static electricity.

  Therefore, in the imaging device 1, the exposed pattern portion that conducts to each connection land is covered with an anisotropic conductive resin material (for example, an anisotropic conductive sheet) prior to the connection portion cutting. During work such as soldering, the anisotropic conductive portion is sandwiched between conductive clips and dropped to the ground, and the connection lands 11, 12, 13 and 14 are kept at the same potential, thereby causing electrostatic breakdown of the solid-state imaging device 3. To prevent. Hereinafter, the structure etc. which employ | adopted the electrostatic breakdown prevention countermeasure are demonstrated in detail using FIG.

  FIG. 3 is a plan view of the FPC applied to the imaging apparatus, and shows the FPC before cutting the potential holding connection portion. FIG. 4 is a side view of the FPC of FIG. 3 in which the solid-state imaging device is mounted and the connection portion is cut, and shows a state where the potential of the anisotropic conductive sheet portion is dropped to the ground.

  As shown in FIG. 3, a connecting portion 15 having a terminal portion 15a is integrally attached to the FPC 5 in a material state before mounting the solid-state imaging device. The solid-state image sensor 3 is mounted on the FPC 5 by TAB, but the coverlay 18 is applied to the front and back surfaces 5a and 5b of the mounting area where the connection lands 11, 12, 13 and 14 on the solid-state image sensor side are arranged. Is done. Similarly, coverlays 19 are also provided on the front and back surfaces of the connection portion 15 side (cable side). In the region between the FPC 5 and the connection portion 15, a connection pattern 16 which is an exposed conductor portion for the FPC 5 such as a connection pattern to the connection lands 11, 12, 13 and 14 and a signal line pattern is exposed on the front and back surfaces. Has been placed. The upper and lower contact patterns 16 are directly covered with an anisotropic conductive sheet 17. Therefore, the connecting portion 15 is cut along the cutting line L1 between the FPC 5 including the contact pattern 16 and the connecting portion 15. Prior to the cutting, the front and back anisotropic conductive sheets 17 are sandwiched between the conductive clips 20. deep. The end of the conductive clip 20 is connected to the ground (GND) via a socket (not shown). Therefore, in the cut state described above, all the contact patterns 16 on the front and back sides are in a conductive state and are kept at the same potential, and the terminal portions of the solid-state imaging device 3, the electronic component 7 and the like are also kept at the same potential.

  Thereafter, the solid-state imaging device mounted FPC 5 with the connection portion 15 disconnected is soldered to the connection lands 11, 12, 13 and 14 with the core wires 61 a and the like of the respective cables while the conductive clip 20 is mounted. The If the conductive clip 20 is mounted until it is necessary to cancel the same potential state of the connection pattern 16, electrostatic breakdown of the solid-state imaging device 3, the electronic component 7, and the like can be prevented. Finally, the conductive clip 20 is removed, the same potential state of the connection pattern 16 is released, the solid-state imaging device 3 is arranged behind the imaging optical system 20, and is housed in the heat shrinkable tube 65 together with the FPC 5.

  When the conductive clip 20 is removed after the soldering of each cable to the connection land 11 or the like, the anisotropic conductive sheet 17 is fixed with an adhesive. Although it is housed in this state, if there is no metal member disposed in the vicinity of the anisotropic conductive sheet 17, there is no fear of short circuit.

  Further, the same effect can be obtained by applying an anisotropic conductive resin directly on the connection pattern 16 instead of the anisotropic conductive sheet 17.

  Further, in the FPC 5 applied to the imaging apparatus 1, the connection pattern 16 of the FPC 5 is grounded via the anisotropic conductive sheet 17 at the time of assembly such as core wire soldering of the cable before being assembled into the imaging apparatus 1 or at the time of inspection. By connecting to a line, the same potential can be maintained. Therefore, the electrostatic resistance of the solid-state imaging device 3 and the like mounted on the FPC 5 is improved. Further, the work for connecting the ground line of the contact pattern 16 may be a simple operation of simply sandwiching the conductive clip 20 between the FPCs 5 and the workability is improved.

Next, the adhesion structure of the flare prevention plate of the imaging optical system and the imaging element holding frame in the imaging apparatus 1 shown in FIG. 1 will be described with reference to FIGS.
FIG. 5 is a front view showing the positional relationship between the cover glass and the flare prevention plate in the imaging apparatus. FIG. 6 is a view in which the cross section of the image sensor holding frame is aligned with the AOB cross section of FIG. 5, and shows a bonding state of the cover glass, the flare prevention plate, and the image sensor holding frame.

  The imaging apparatus 1 is particularly characterized by an adhesion structure of a flare prevention plate and an imaging element holding frame of an imaging optical system disposed in front of a solid-state imaging element of the imaging apparatus. The configuration itself is the same as that shown in FIG.

  Usually, in an objective optical system without a centering lens, it is necessary to fix the flare prevention plate 25 to the image sensor holding frame 24 with the flare prevention plate 25 and the image area of the solid-state image sensor positioned. However, conventionally, there is little bonding allowance for each fixing, so that the adhesive sticks out into the photographing optical path, the adhesive force is insufficient, or the adhesive layer is too thick to easily float. The imaging apparatus 1 solves such a problem and provides a frame configuration that enables stable assembly work.

  As shown in FIG. 5, the flare prevention plate 25 is provided with an opening 26 that matches the image area and image mask shape of the solid-state imaging device 3. The outer shape of the flare prevention plate 25 is circular, and has a size such that the square of the rectangular cover glass 4 is exposed when the cover glass 4 is bonded. Further, a V-shaped cutout portion 27 is formed at the lower end side of the cover glass 4 of the flare prevention plate 25. Accordingly, the square of the cover glass 4 and the portion of the cover glass 4 on the cutout portion 27 of the flare prevention plate 25 are exposed from the flare prevention plate 25.

  A method of bonding and fixing the cover glass 4, the flare prevention plate 25, and the image sensor holding frame 24 in the image pickup apparatus 1 will be described. First, as shown in FIG. 6, an adhesive is applied to the surface of the cover glass 4 to prevent flare. The plate 25 is bonded together. At this time, the adhesive layer can be thinly finished by curing while positioning and pressing both with a jig. Next, the rear surface of the image sensor holding frame 2424 is aligned with the anti-flare plate 25, and the adhesive 30 is placed on the corner portions and the cutout portions 27 of the cover glass 4 shown in FIG. In this bonded state, the thickness of the adhesive layer between the image sensor holding frame 24 and the cover glass 4 is ensured by the thickness of the flare prevention plate 25. Further, the adhesive 30 exceeding the required amount is pushed outward because the flare prevention plate 25 becomes a wall, and the adhesive 30 does not flow into the mating surface between the flare prevention plate 25 and the image sensor holding frame 24. The adhesive 30 pushed outward is wiped from the outside, and then the adhesive portion is cured.

  According to the above-described adhesion structure of the flare prevention plate and the imaging element holding frame of the imaging optical system in the imaging apparatus 1 described above, the assembly state in which the adhesive state does not protrude from the imaging surface, is insufficiently bonded, or does not float on the adhesive surface is stable. It can be realized in the work, and stable optical performance of the imaging device can also be obtained.

Next, the adhesion structure of the 1st and 2nd modification with respect to the adhesion structure of the flare prevention board in this image pick-up device 1 and an image pick-up element holding frame is demonstrated.
FIG. 7 shows a bonding state of a cross-sectional view corresponding to the AO cross section of FIG. 5 of the cover glass, the flare prevention plate, and the image sensor holding frame in the first modified example. FIG. 8 shows a bonding state of a cross-sectional view corresponding to the AO cross section of FIG. 5 of the cover glass, the flare prevention plate, and the image sensor holding frame in the second modified example.

  The cover glass 4 and the flare prevention plate 25 applied to the first and second modified examples have the same shape as that applied to the imaging apparatus 1, but the image sensor holding of the first and second modified examples is used. The frames 24A and 24B have different AO cross-section (diagonal direction cross-section) shapes as shown in FIG. 7 or FIG.

  That is, in the first modified example, as shown in FIG. 7, the adhesive pool portion 28 is provided at the contact portion between the image sensor holding frame 24 </ b> A and the flare prevention plate 25. By providing the adhesion pool 28, the protrusion of the adhesive 30 to the outside can be reduced, and at the same time, a stronger adhesion fixing state can be obtained.

  On the other hand, in the second modification, as shown in FIG. 8, a protrusion 29 extending to the middle position in the thickness direction is formed outside the cover glass 4 on the outer periphery of the image sensor holding frame 24B. The adhesive 30 is pushed out to the side surface of the cover glass 4 along the protruding portion 29, and this portion functions as an adhesive pool. Therefore, the protrusion of the adhesive 30 to the outside can be reduced as in the first modification, and at the same time, a stronger adhesive fixing state can be obtained.

Next, the structure of the lens and diaphragm constituting the imaging optical system in the imaging apparatus 1 will be described with reference to FIGS.
FIG. 9 is a cross-sectional view illustrating a state where the lens holding frame and the lens are assembled in the imaging apparatus. FIG. 10 is a diagram illustrating a process in which the first lens constituting the imaging optical system of the imaging apparatus is glass-molded and the diaphragm is formed by vapor deposition.

  The imaging apparatus 1 is particularly characterized by the structure of a lens frame and a diaphragm that holds the imaging optical system of the imaging apparatus, and the configuration itself including the imaging optical system of the imaging apparatus 1 is that shown in FIG. The same shall apply.

  By the way, in the conventional imaging device, the lens itself becomes smaller as the size is reduced, and accordingly, processing and assembling of the lens frame and the aperture become difficult. The imaging apparatus 1 provides a method capable of improving the workability and assembling property of a lens frame and a diaphragm that become a problem with the downsizing.

  Further, in the conventional imaging apparatus, it is very difficult to arrange a flare or a diaphragm (brightness diaphragm plate) in a portion where the distance between the lens surfaces is very narrow. Furthermore, conventionally, when a diaphragm is formed on a lens by masking vapor deposition, it has been difficult to cope with high accuracy in terms of eccentricity and the like. The imaging apparatus 1 provides an imaging apparatus in which the diaphragm can be arranged even with the lens configuration as described above. Further, the diaphragm can be formed with high precision by glass molding and vapor deposition even with a narrow lens interval. A forming method is provided.

  The imaging optical system in the imaging apparatus 1 includes a first lens 34 shown in FIG. 9, a second lens 36, a diaphragm (brightness diaphragm plate) 35 interposed between the lenses, and a flare prevention shown in FIG. The optical system includes a plate 32 and a third lens 37, and these optical systems are fixedly supported by the lens frame 31.

  The lens frame 31 is a member having a smaller inner diameter on the front end side (front) and a larger inner diameter on the rear end side. When the above optical systems are incorporated into the lens frame 31, the first lens 34, the diaphragm 35, and the second lens 36 are bonded and fixed in advance. The lens positioning jig 53 is fitted and inserted into the large diameter portion of the lens frame 31, and the end surface of the lens positioning jig 53 is brought into contact with the step surface 31a of the large diameter portion and the small diameter portion. Therefore, the first lens 34, the diaphragm 35, and the second lens 36 integrated by bonding are fitted and inserted into the small-diameter portion side of the lens frame 31, and the convex portion of the second lens 36 is used as the end surface of the lens positioning jig 53. Position it in contact with. The first lens 34 is bonded and fixed at the tip of the lens frame 31 under the positioning state. Thereafter, as shown in FIG. 1, the flare prevention plate 32, the spacing tube 33, and the third lens 37 are sequentially dropped from the rear side of the lens frame 31, and the lens frame 31 and the third lens 37 are bonded and fixed.

  The imaging optical system 20 is attached in the lens frame 31 as described above. Since the lens frame 31 is a frame member having a large-diameter portion formed on the rear side, it is easy to process and can be processed with high accuracy. Further, each lens is accurately positioned by the lens frame 31.

  On the other hand, in the imaging optical system of the imaging apparatus 1, as shown in FIG. 9, the second lens 36 is a concave / convex (menis) lens, and the diaphragm 35 usually has a thickness of about several tens of μm. The diaphragm 35 is provided between the first lens 34 and the second lens 36. That is, the diaphragm 35, which is a light shielding portion, is generated by vapor deposition on a step portion 39 formed by glass molding the central convex light transmitting portion 38 of the first lens 34. By arranging the diaphragm 35 in this way, even if the distance between the surfaces of the translucent part 38 and the second lens 36 is designed at a level of several tens of μm, the thickness of the step part 39 and the diaphragm 35 can be set appropriately. The diaphragm can be manufactured and arranged stably.

  As described above, the first lens 34 is glass-formed, and the diaphragm 35 is formed by vapor-depositing the glass-formed step portion 39 of the first lens 34. The glass forming, vapor deposition, and polishing processes will be described with reference to FIG. 10. First, as shown in FIG. 10A, the material of the first lens 34 is glass-formed to form a central convex shape 38. Subsequently, as shown in FIGS. 10B and 10C, a coating 40 by vapor deposition is applied to the entire exit surface of the first lens 34. Further, as shown in FIG. 10D, when the coating portion of the convex portion 38 is polished and removed, the diaphragm 35 and the light transmitting surface 38 are obtained.

  As described above, according to the imaging optical system of the imaging apparatus 1, the position of the aperture opening, that is, the translucent surface 38 is determined at the stage of glass molding of the first lens 34. The diaphragm 35 can be manufactured with higher accuracy than the conventional masking vapor deposition method.

Next, an electronic endoscope apparatus incorporating an imaging apparatus related to the imaging apparatus 1 will be described with reference to FIGS.
FIG. 11 is a diagram showing an external appearance of the electronic endoscope apparatus. FIG. 12 is a cross-sectional view showing an arrangement of an imaging illumination system and an imaging optical system provided at the distal end of the scope at the distal end of the bending portion of the electronic endoscope apparatus.

  By the way, conventionally, an imaging illumination lens for an endoscope is disposed at a position close to the outer periphery of the scope. Therefore, when the illumination lens is close to an observation target, there is a problem that whiteout is likely to occur at that portion. In addition, since the objective lens and the illumination lens are separated from each other, sufficient brightness may not be ensured due to uneven illumination during macro observation. According to the electronic endoscope apparatus 41, it is possible to provide an endoscope apparatus that solves the above-described problems and has improved observation performance by performing optimal illumination.

  As shown in FIG. 11, in the electronic endoscope device 41, a scope distal end portion 42 is attached to the distal end of the bending portion 43. As shown in FIG. 12, a first lens 34 that is an objective lens of the imaging optical system and an illumination concave lens 44 of the imaging illumination system located at the distal end of the fiber bundle 45 are arranged in parallel on the scope distal end portion 42 as shown in FIG. ing.

  The first lens 34 has a visual field range of a predetermined angle with the optical axis O as the center. Further, the optical axis OF of the fiber bundle 45 is arranged with a distance δ1 offset from the optical axis OL of the illumination concave lens 44 toward the center of the scope or to the first lens side. Accordingly, the illumination range by the concave lens 44 is a wide angle on the first lens side and a narrow angle on the anti-first lens side. In the illumination state, the near point side of the visual field range of the first lens 34 is illuminated, and the amount of light in the peripheral portion of the scope on the illumination concave lens 44 side is reduced. Accordingly, since an excessive light distribution state does not occur even with respect to a subject on the outer periphery of the scope close to the illumination lens, an observation image without whiteout can be obtained. In addition, since the near point side of the field of view is illuminated, a good light distribution state is maintained even during macro observation, and the observation image does not become dark.

  According to the imaging illumination system of the endoscope apparatus 41, an observation image without whiteout is obtained. In addition, a good light distribution state is maintained even during macro observation, and the observation image does not become dark.

  The proof range by the concave lens 44 is preferably set so as to cover the near point side of the visual field range of the first lens 34 and to cover the far point side. The above setting can be made by appropriately adjusting the offset amount δ1 between the optical axis OL of 44 and the optical axis OF of the fiber bundle 45.

Next, a modified example of the imaging illumination system in the electronic endoscope apparatus 41 will be described with reference to FIG.
FIG. 13 is a cross-sectional view of the imaging illumination system and the imaging optical system provided at the distal end of the scope applied to this modification.

  The imaging illumination system of this modification is different from the imaging illumination system of the electronic endoscope apparatus 41 in that a convex lens 46 is applied as the illumination system, and the optical axis OL of the convex lens 46 is set to the optical axis OF of the fiber bundle 45. Thus, the distance δ2 is offset toward the center of the scope or in the direction closer to the first lens side.

  In the imaging illumination system of the present modification, the illumination convex lens 46 is arranged in the state offset to the first lens side as described above, so that the illumination range by the convex lens 46 becomes a wide angle on the first lens side, which is anti-second. One lens has a narrow angle. In the illumination state, the near point side of the visual field range of the first lens 34 is illuminated, and the amount of light in the peripheral portion of the scope on the illumination convex lens 46 side is reduced. Therefore, this modification also has the same effect as the above.

Next, the arrangement of the imaging illumination system and imaging optical system at the distal end of the scope in the electronic endoscope apparatus 41 will be described with reference to FIG.
FIG. 14 is a front view of the distal end portion of the scope in the electronic endoscope apparatus.

  By the way, in the conventional endoscope apparatus, the shadow of the forceps may be noticeable depending on the positional relationship among the illumination lens, the objective lens, and the forceps opening. According to this electronic endoscope apparatus, the shadow of the forceps can be made inconspicuous by optimally adjusting these positional relationships.

  Furthermore, since the endoscope for upper gastrointestinal tract is inserted nasally or orally, a thin insertion portion diameter has been conventionally required to reduce patient pain. On the other hand, when considering the structure of the nasal cavity and pharynx and the insertion method, the entire insertion portion is not required to have a uniform small diameter, and if the diameter is reduced in a specific direction, the same insertion property is obtained. It can be secured. An object of the present electronic endoscope apparatus is to realize an apparatus that can adopt an optimum endoscope distal end shape and bending operation direction without affecting insertability.

  The electronic endoscope apparatus 41 includes an illumination lens, an objective lens, and a forceps port appropriately arranged in the illumination optical system and the imaging optical system according to a modification of the electronic endoscope apparatus 41, and a distal end portion. The bending direction (bending direction) is set in two directions, and the reference numerals of the constituent members will be described by applying the same reference numerals as those of the above-described modified example.

  As shown in FIG. 14, at the scope distal end portion 42 in the electronic endoscope apparatus 41, the first lens 34 is located at the substantial center of the scope distal end portion 42, and on the right side (left side in FIG. 14) of the forceps port 47. Further, the illumination convex lens 46 is arranged on the left side (right side in FIG. 14) so that the centers thereof are arranged in a substantially straight line (substantially in the left-right direction). By arranging in this way, the forceps observation image and the shadow direction coincide with each other, so that the forceps shadow is completely hidden in the observation image, the forceps shadow does not occur, and there is no dark portion. Can be obtained. An air / water supply nozzle 48 is disposed above the scope tip 42.

  Further, as shown in FIG. 14, the scope distal end portion 42 in the electronic endoscope apparatus 41 forms an elliptical shape having short sides in the U and D directions (vertical direction in FIG. 14) with respect to the circular cross section 50. ing. Two bending operation wires 49 are arranged in the U and D directions. The wire 49 can be operated to perform a bending operation in two directions, U and D.

  When the scope tip portion 42 of the electronic endoscope apparatus 41 is inserted orally, it is inserted while bending the endoscope along the shape of the pharynx when passing through the pharynx. At this time, since the outer diameters in the U and D directions to be curved are small, the frequency of touching the pharynx is reduced, and the patient's pain is also reduced. On the other hand, when inserting the nasal cavity, the nasal cavity must be inserted into a complicated shape, but it should be inserted while curving in the direction U or D in the direction where the diameter of the insertion part is small in accordance with the shape of the nasal cavity. If you can, you can insert without resistance.

Next, a modification of the scope end portion of the electronic endoscope apparatus 41 will be described with reference to FIG.
FIG. 15 is a front view of the distal end portion of the scope in the modified example. Note that the scope distal end portion 42A of the electronic endoscope apparatus according to the present modification includes two illumination lenses with respect to the scope distal end section 42 of the electronic endoscope apparatus 41, and the bending operation direction is set to four directions. The reference numerals of the constituent members will be described by applying the same reference numerals as those of the electronic endoscope apparatus 41.

  In the scope distal end portion of this modification, as shown in FIG. 15, two illumination lenses 44 are arranged on both sides with a line connecting the center of the first lens 34 and the forceps opening 47 to the scope distal end portion 42A as a center line. . The arrangement angle θ1 on both sides of the illumination lens 44 is 30 ° or less.

  In this modification, by applying the two illumination lenses 44 and adopting the above-described arrangement, a shadow is reflected in the vicinity of the observation image of the forceps, so that the shadow of the forceps becomes inconspicuous. In addition, since the two illumination lenses 44 are disposed at symmetrical positions, the darkness of the shadow can be reduced.

  On the other hand, the scope distal end portion 42A in this modification has an elliptical shape with short sides in the L and R directions (left and right directions in FIG. 15) with respect to the circular cross section 50 as shown in FIG. Then, two bending operation wires 49A are arranged in the upper and lower U and D directions, and two bending operation wires 49B are arranged in the left and right L and R directions. These wires 49A and 49B can be operated to perform bending operations in four directions of U, D, L, and R directions.

  Also in this modification, when the scope distal end portion 42A is orally inserted, it is inserted while bending the endoscope along the shape of the pharynx when passing through the pharynx. The bending directions are four directions, and the bending operation in the L and R directions with small outer diameters in the bending direction can be selected as necessary, so that the frequency of touching the pharynx is further reduced and the patient's pain is reduced. In addition, a nasal cavity having a complicated shape must be inserted when inserting the nasal cavity, and the direction in which the insertion portion is bent is L or R having a small diameter, and the direction is matched to the shape in the nasal cavity. If it is inserted, it can be inserted without resistance.

(Appendix)
Based on the contents described above, the following configuration is obtained. That is,
(Appendix 1)
In an imaging device having a double-sided flexible board that mounts a plurality of electronic components on one side and connects cables on the other side,
It is characterized by comprising a connection land arranged so as to straddle each other on the other surface side of the double-sided flexible substrate so as to straddle at least the back surface portions facing the two electronic components mounted in the longitudinal direction of the one surface side of the substrate. An imaging device.

(Appendix 2)
In an imaging device having a double-sided flexible board that mounts a plurality of electronic components on one side and connects cables on the other side,
A land for connection disposed on the other side of the double-sided flexible substrate, so as to straddle each other at least the back surface portions facing the two electronic components mounted in the longitudinal direction of the one surface of the substrate;
A cable connected to the connection land;
An imaging apparatus comprising:

(Appendix 3)
In an imaging apparatus having a substrate to which an imaging element is connected,
An image pickup apparatus, wherein an exposed conductor portion that is not covered with an insulating material is provided on a part of the substrate, and the exposed conductor portion is covered with an anisotropic conductive resin material.

  The imaging device according to the present invention is less affected by external force and vibration, and can be used as an imaging device including a highly reliable electric circuit board.

It is sectional drawing of the front-end | tip part of the imaging device which is one Embodiment of this invention. It is the top view which looked at FPC installed in the imaging device of FIG. 1 from the back surface side of a board | substrate, and also showed through the component mounting surface of this board | substrate. It is a top view of FPC applied to the imaging device of FIG. 1, Comprising: FPC before cut | disconnecting the same electrical potential holding | maintenance connection part is shown. FIG. 4 is a side view of the FPC of FIG. 3 in which a solid-state imaging device is mounted and the same potential holding connection portion is cut, showing a state where the potential of the anisotropic conductive sheet portion is dropped to the ground. It is a front view which shows the positional relationship of the cover glass and flare prevention board in the imaging device of FIG. It is the figure which match | combined and showed the image pick-up element holding frame cross section to the AOB cross section of FIG. 5, and shows the adhesion state of a cover glass, a flare prevention board, and an image pick-up element holding frame. It is sectional drawing corresponding to the AO cross section of FIG. 5 of the cover glass in the 1st modification of the imaging device of FIG. 1, a flare prevention board, and an image pick-up element holding frame, and shows the adhesion state. It is sectional drawing corresponding to the AO cross section of FIG. 5 of the cover glass in the 2nd modification of the imaging device of FIG. 1, a flare prevention board, and an image pick-up element holding frame, and shows the adhesion state. It is sectional drawing which shows the assembly | attachment state of the lens holding frame and lens in the imaging device of FIG. It is a figure which shows the process in which the 1st lens applied to the imaging device of FIG. 1 is glass-molded, and forms an aperture_diaphragm | restriction by vapor deposition. It is a figure which shows the external appearance of the electronic endoscope apparatus incorporated in the imaging device relevant to the imaging device of FIG. It is sectional drawing which shows arrangement | positioning with the illumination system and imaging optical system provided in the scope front-end | tip part of the front-end | tip of the bending part of the electronic endoscope apparatus of FIG. It is sectional drawing of the illumination system and imaging optical system which are provided in the scope front-end | tip part in the modification of the electronic endoscope apparatus of FIG. FIG. 12 is a front view of a distal end portion of a scope in the electronic endoscope apparatus of FIG. 11. FIG. 12 is a front view of a distal end portion of a scope in a modified example of the electronic endoscope apparatus of FIG. 11.

Explanation of symbols

3 ... Solid-state image sensor (electronic component)
5 ... FPC (Double-sided flexible board)
5a: One side of FPC (one side of double-sided flexible board)
5b ... the other side of the FPC (the other side of the double-sided flexible board)
7, 8, 9, 10
... Electronic parts 11, 12, 13, 14
... Connection land (connection part)
61a, 62a, 63a, 64a
... End core (cable core)

Agent Patent Attorney Susumu Ito

Claims (2)

In an imaging apparatus having a double-sided flexible board in which a plurality of electronic components are mounted on one side and a connecting portion for connecting a core wire of a cable is provided on the other side.
The connection part is a connection land disposed on the other surface side of the double-sided flexible substrate, and two electrons mounted on at least one surface side longitudinal direction of the substrate on the other surface side of the double-sided flexible substrate. An image pickup apparatus, comprising: a connection land disposed so as to straddle a back surface portion facing a component.   The imaging apparatus according to claim 1, wherein the connection portion is a connection land for connecting the core wires of the cable with solder.

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