JP2014136090A - Optical scanning endoscope and method of assembling the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent disconnection of a wire while an optical scanning endoscope is assembled.SOLUTION: An optical scanning endoscope comprises: a control circuit for generating a control signal which controls the supply of drive power by a circuit board of a scanning optical unit; and a shield cable for transferring the control signal from the control circuit to the circuit board. The circuit board is disposed parallel to a longitudinal direction of an optical fiber such that its back side is opposed to the optical fiber, and has on its front side a plural solder lands to connect a shield cable and a plurality of wiring patterns. The shield cable is soldered to the plurality of solder lands along the surface of the circuit board, and is wired to extend in the longitudinal direction of the optical fiber. The plurality of solder lands extend in the longitudinal direction of the optical fiber, and include a grounding solder land to which the braided shield of the shield cable is connected.

Description

  The present invention relates to an optical scanning endoscope including a scanning optical unit that vibrates a free end of an optical fiber supported in a cantilever manner and periodically scans illumination light emitted from the free end on a subject, and the same The present invention relates to an assembly method.

  An electronic endoscope is known as a device used when a doctor observes a patient's body. CCDs (Charge Coupled Devices) and CMOSs (Complementary Metal Oxide Semiconductors) are used as conventional image pickup devices for general electronic endoscopes, but the endoscopes can be further reduced in diameter. A next-generation optical scanning device disclosed in Patent Document 1 has been proposed as an imaging device. Hereinafter, an endoscope provided with this optical scanning device at the tip is referred to as an optical scanning endoscope.

  Endoscopes equipped with an imaging device at the tip, such as electronic endoscopes and optical scanning endoscopes, for example, bundle a plurality of wires (signal lines and power lines) for driving the imaging device and cover them with a braided shield. Equipped with shielded cable. A circuit board for driving the imaging device is disposed at the distal end portion of such an endoscope, and one end of the shield cable is connected to the circuit board.

  In the conventional electronic endoscope, as disclosed in Patent Document 2, a configuration in which the sheath of the shield cable and the braided shield are peeled off in front of the front end portion and only the wire is connected to the circuit board is generally employed. ing.

US Pat. No. 6,294,775 JP 2000-121959 A

  In the optical scanning endoscope, an extremely thin wire having a conductor diameter of several tens of μm is used to reduce the diameter of the insertion portion. Therefore, in the configuration in which only the wire of the shielded cable is connected to the circuit board, there is a problem that the wire breaks easily during assembly work because the wire breaks even with a slight force about the weight of the circuit board. . In addition, it is necessary to use a jig for holding the shielded cable and the circuit board in a predetermined positional relationship so that no force is applied to the wire during the assembly work, resulting in a problem that work efficiency is lowered. there were.

  According to an embodiment of the present invention, an optical scanning type including a scanning optical unit that vibrates a free end of an optical fiber supported in a cantilever manner and periodically scans illumination light emitted from the free end on a subject. The endoscope is a endoscope, the scanning optical unit is provided in the vicinity of the free end of the optical fiber, and a fiber driving unit that presses and bends the side surface of the optical fiber, and the fiber driving unit moves along the longitudinal direction of the optical fiber. By moving the optical fiber, there are provided a fiber moving means for moving the free end of the optical fiber along the longitudinal direction of the optical fiber, and a plurality of wiring patterns electrically connected to at least one of the fiber driving section and the fiber moving means. And a circuit board for supplying driving power for driving at least one of the fiber driving unit and the fiber moving means via the plurality of wiring patterns; The optical scanning endoscope includes a control circuit that generates a control signal for controlling the supply of driving power by the circuit board, a plurality of electric wires that transmit the control signal from the control circuit to the circuit board, and the plurality of electric wires A shield cable having a braided shield that shields the electric wires of the circuit board, and the circuit board is arranged in parallel with the longitudinal direction of the optical fiber so that the back side faces the optical fiber, and a plurality of electric wires are provided on the front side. It has a plurality of signal solder lands for soldering to the wiring pattern and a ground solder land for soldering the braided shield, and the braided shield is attached to the grounded solder land so as to follow the surface of the circuit board. An optical scanning endoscope is provided, which is soldered, and then a plurality of electric wires are soldered to a plurality of signal solder lands.

  According to this configuration, since the braided shield with high rigidity is soldered to the circuit board, the positional relationship between the shield cable and the circuit board is stabilized, and the wire breaks even if a thin wire is connected to the circuit board. Is less likely to occur.

  In the above-described optical scanning endoscope, the tip of the shield cable may be configured such that the sheath is removed and the exposed braided shield is twisted into a rod shape and fixed in shape by solder.

  According to this configuration, since the rigidity of the braided shield is remarkably improved, the positional relationship between the shield cable and the circuit board is further stabilized, and the wire breakage is less likely to occur.

  In the above optical scanning endoscope, the grounding solder lands may extend in the longitudinal direction of the optical fiber, and the signal solder lands may be disposed on both sides of the grounding solder lands.

  According to this configuration, due to the shielding effect of the braided shield, signal interference between control signal wires arranged on opposite sides of the braided shield is reduced. Further, since the bulky braided shield is arranged at the center of the circuit board, when the circuit board is accommodated in the cylindrical protective cover, the height from the circuit board to the inner wall surface of the protective cover is the center of the circuit board. Therefore, the braided shield and the protective cover do not easily interfere with each other, which is advantageous for downsizing (thinning the diameter) of the protective cover.

  In the above optical scanning endoscope, the scanning optical unit has a substantially cylindrical support member that supports the fiber drive unit, the fiber moving means, and the circuit board, and the surface of the circuit board is the outer periphery of the support member. It is good also as a structure exposed to the surface.

  In the above configuration, a cutout portion that holds the shield cable in a predetermined position may be formed at the base end portion of the support member.

  According to this configuration, since the shielded cable is held at a predetermined position, the positional relationship between the shielded cable and the circuit board is further stabilized, and the disconnection of the wire is less likely to occur.

  According to an embodiment of the present invention, light having a scanning optical unit at the tip thereof that vibrates the free end of the optical fiber supported in a cantilever manner and periodically scans illumination light emitted from the free end on the subject. A method for assembling a scanning endoscope for controlling driving of a scanning optical unit on a circuit board on which a plurality of wiring patterns for control signals and a ground pattern are formed in order to control driving of the scanning optical unit Arranged along the longitudinal direction of the shielded cable having a plurality of electric wires for transmitting the control signal and a braided shield for shielding the plurality of electric wires, and soldering the braided shield at the tip of the shielded cable to the ground pattern, and The process of soldering the signal line at the tip of the shielded cable to each wiring pattern and the circuit board to which the shielded cable is connected And a circuit board is provided in the vicinity of the free end of the optical fiber and presses and bends the side surface of the optical fiber. Electrically connecting to the fiber moving means for moving the free end of the optical fiber forward and backward along the longitudinal direction of the optical fiber by moving along the direction, and bonding and fixing the shielded cable to the support member And a method for assembling the optical scanning endoscope characterized by comprising:

  Further, in the above assembling method, the step of soldering the braided shield to the ground pattern includes removing the sheath at the tip of the shield cable to expose the braided shield, and releasing the braided shield to be accommodated in the braided shield. The step of exposing the signal line, the step of twisting the braided shield into a bar shape, and the step of soaking the solder by heating the braided shield twisted into a bar shape may be adopted.

  The above configuration may further include a step of applying a sealing material to the soldered portion after the step of soldering the signal line at the tip of the shielded cable to the wiring pattern.

  According to this configuration, deterioration of the soldered portion is suppressed, and reliability is improved.

  In the above configuration, the ground pattern is formed so as to extend substantially in the center of the circuit board in the longitudinal direction of the shielded cable, and the plurality of wiring patterns are formed on both sides of the ground pattern. It is good.

  In the above configuration, the method further includes a step of attaching the circuit board to the fiber driving unit or the fiber moving unit before the step of electrically connecting the circuit board to the fiber driving unit or the fiber moving unit. In the step of accommodating in the support member of the unit, the fiber driving unit or the fiber moving means to which the circuit board is attached may be accommodated in the support member.

  According to this configuration, wiring connection work between the fiber driving unit or the fiber moving means and the circuit board is facilitated.

  According to the configuration of the embodiment of the present invention, the wire is less likely to be disconnected during the assembly of the optical scanning endoscope.

1 is a block diagram illustrating a schematic configuration of a scanning confocal endoscope apparatus according to an embodiment of the present invention. It is a see-through | perspective side view which shows schematic structure of the confocal scanning optical unit which concerns on embodiment of this invention. It is a perspective view which shows schematic structure of the connection part of a Z-axis drive circuit and a shield cable. It is the cross-sectional view which cut | disconnected the confocal scanning optical unit after assembly in the base end vicinity of a circuit board. It is a figure explaining the procedure which connects a shield cable to a confocal scanning optical unit. It is a figure which shows schematic structure of the front-end | tip part of the confocal observation type | system | group integrated electronic endoscope which is another embodiment of this invention.

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

  FIG. 1 is a block diagram showing a schematic configuration of a scanning confocal endoscope apparatus 1 according to an embodiment of the present invention. The scanning confocal endoscope apparatus 1 is a medical observation system designed by applying the principle of a confocal microscope and capable of observing a subject with high magnification and high resolution. In addition, the scanning confocal endoscope apparatus 1 disperses a fluorescent dye that selectively binds to a substance specific to a specific cancer tissue in advance on an observation site, and irradiates the observation field with excitation light of the fluorescent dye. Fluorescence endoscopy (dye method) for observing cancer tissue using fluorescence emitted from a fluorescent dye bound to the cancer tissue is performed.

  As shown in FIG. 1, the scanning confocal endoscope apparatus 1 includes a processor 100, a confocal probe 200, and a monitor 300.

  The confocal probe 200 is flexible to be inserted into a patient's body (for example, in the digestive tract) through a connection portion (control box) 200a connected to the processor 100 and a treatment instrument insertion channel of an electronic endoscope (not shown). It is comprised from the elongate cable-shaped insertion part 200b which has. The insertion portion 200b includes a confocal scanning optical unit 220 provided at the tip thereof, and a cable portion 210 that connects the confocal scanning optical unit 220 and the connection portion 200a. Endoscopic observation using the scanning confocal endoscope apparatus 1 is performed in a state where the distal end surface of the insertion portion 200b of the confocal probe 200 is pressed against a subject (for example, the inner wall surface of the digestive tract).

  In the confocal probe 200 of this embodiment, the insertion portion 200b has a small diameter of about 2 mm (the inner diameter of the sheath is about 1.4 mm) so that the observation field can be accessed through the treatment instrument insertion channel of the electronic endoscope. Is formed. Further, the cable unit 210 accommodates an SMF (single mode optical fiber) 211 and shielded cables 212a and 212b.

  The connection unit 200a includes a CPU 202, a memory 204, and a scanning control circuit 206 (signal generation circuit). The processor 100 and the connection part 200a of the confocal probe 200 are optically and electrically connected by an optical connector 152 and an electrical connector 154, respectively.

  The CPU 202 controls each part of the confocal probe 200 in an integrated manner under the control of the processor 100. The memory 204 stores probe information including identification information of the confocal probe 200 and information (properties) regarding various characteristics. The probe information stored in the memory 204 is read by the CPU 202 when the system is activated and transmitted to the processor 100.

  The scanning control circuit 206 controls driving of an XY axis actuator 223 and a Z axis actuator 227 described later provided in the confocal scanning optical unit 220. The control signal for the XY axis actuator 223 output from the scanning control circuit 206 is transmitted by the shield cable 212b, and the control signal for the Z axis actuator 227 is transmitted by the shield cable 212a.

  The processor 100 includes a CPU 102, a memory 104, a light source 106, a photodetector 108, an optical coupler 110, a video signal processing circuit 112, and an image memory 114. The CPU 102 controls each part of the processor 100 and the confocal probe 200 in an integrated manner. The memory 104 stores various programs executed by the CPU 102.

  The light source 106 is a semiconductor laser light source that generates blue light that is excitation light of a fluorescent dye scattered on an observation site. Excitation light emitted from the light source 106 is input to one of branch ports (described later) of the optical coupler 110 via the SMF 110a.

  The optical coupler 110 is a 1 × 2 branch optical coupler having one common port and two branch ports. One of the branch ports is connected to the light source 106 via the SMF 110a, and the other is connected to the photodetector 108 via the SMF 110b. Further, the common port of the optical coupler 110 is connected to the SMF 211 of the confocal probe 200 via the SMF 110c. The excitation light output from the light source 106 is input to the optical coupler 110 from one of the branch ports and output from the common port. The excitation light output from the common port of the optical coupler 110 is coupled to the SMF 211 of the confocal probe 200 connected to the SMF 110c by the optical connector 152 via the SMF 110c connected to the common port.

  As will be described later (FIG. 2), the distal end portion 211 a of the SMF 211 of the confocal probe 200 is accommodated in the confocal scanning optical unit 220. The excitation light that has propagated through the SMF 211 exits from the tip 211a and is irradiated onto the subject. The fluorescent dye bound to the tissue of the subject absorbs excitation light, excites it, and emits fluorescence. Part of the fluorescence emitted from the fluorescent dye (observation light) is incident on the tip portion 211a of the SMF 211 in the confocal scanning optical unit 220, and propagates through the SMF 211 and SMF 110c in the direction opposite to the traveling direction of the excitation light during irradiation. Then, it is input to the optical coupler 110 from the common port. One of the observation lights branched into two by the optical coupler 110 is input to the photodetector 108. Based on the intensity of the observation light detected by the photodetector 108, the video signal processing circuit 112 at the subsequent stage forms a fluorescence observation image and outputs it to the monitor 300 as a video signal.

  Next, details of the confocal scanning optical unit 220 provided at the distal end of the insertion portion 200b of the confocal probe 200 will be described. FIG. 2 is a perspective side view showing a schematic configuration of the confocal scanning optical unit 220. In the following description of the confocal scanning optical unit 220, the longitudinal direction of the confocal scanning optical unit 220 (longitudinal direction of the distal end portion 211a of the SMF 211) is the Z direction, and two directions orthogonal to the Z direction and orthogonal to each other are the X direction. And Y direction. In the longitudinal direction (Z-axis direction) of the confocal scanning optical unit 220, one end (the right end in FIG. 2) connected to the cable unit 210 is referred to as a base end, and the other end (the left end in FIG. 2) is referred to as a front end. .

  As shown in FIG. 2, the confocal scanning optical unit 220 includes a housing 221, a movable frame 222, an XY axis actuator (fiber drive unit) 223, an objective optical system 224, a fixed frame (support member) 226, a Z axis actuator 227 ( Fiber movement means), a Z-axis position sensor 228, and a cylindrical cover 229 (shown only in FIGS. 4 and 5) covering the entire confocal scanning optical unit 220.

  The housing 221 is a case that accommodates each part of the confocal scanning optical unit 220, and includes an outer cylinder 221a and an inner cylinder 221b, which are substantially cylindrical metal members. The inner cylinder 221b is accommodated coaxially within the outer cylinder 221a without any gap, and is guided by the inner peripheral surface of the outer cylinder 221a so as to be slidable in the Z-axis direction within the outer cylinder 221a. The opening on the distal end side of the outer cylinder 221a is closed by a transparent window 221c.

  An objective optical system 224 composed of a plurality of lenses (not shown) is held at the tip of the inner cylinder 221b. A movable frame 222 and an XY axis actuator 223 are attached to the inner side of the inner cylinder 221b.

  The XY axis actuator 223 oscillates (resonates) the tip portion 211a of the SMF 211 in the X axis and Y axis directions and periodically scans the excitation light emitted from the tip of the SMF 211. The XY axis actuator 223 includes a main body 223a formed of a substantially cylindrical piezoelectric element, and a scanning drive circuit 223b that supplies a driving voltage (X axis driving voltage, Y axis driving voltage) to the main body 223a. The main body 223a is held coaxially in the inner cylinder 221b. A through hole (not shown) having a diameter substantially the same as the outer diameter of the SMF 211 is formed on the central axis of the main body 223a. The SMF 211 is inserted into the through hole from the base end side, and is fixed by adhesion. The tip portion 211a of the SMF 211 protrudes from the tip of the main body 223a by a predetermined length and is cantilevered by the main body 223a. That is, the tip of the SMF 211 is a free end.

  On the peripheral surface of the main body 223a of the XY axis actuator 223, two electrode pairs (X axis driving electrode pair, Y axis driving electrode pair) (not shown) are provided. When an X-axis drive voltage (Y-axis drive voltage) is applied to the X-axis drive electrode pair (Y-axis drive electrode pair) of the XY-axis actuator 223, the main body 223a of the XY-axis actuator 223 moves in the X-axis direction due to the reverse piezoelectric effect. Curved in the Y-axis direction. By the bending drive of the XY axis actuator 223, the side surface of the SMF 211 inserted into the through hole of the main body 223a is pressed and displaced in a direction perpendicular to the longitudinal direction thereof, so that the SMF 211 cantilevered by the main body 223a is displaced. The tip 211a swings (bends) in the X-axis and Y-axis directions.

  The excitation light emitted from the tip 211a of the SMF 211 is collected by the objective optical system 224, passes through the window 221c, and then forms a spot (beam waist) outside the confocal scanning optical unit 220. Since the spot of the excitation light is formed in the immediate vicinity of the window 221c, when the tip of the confocal probe 200 is pressed against the subject, the spot of the excitation light is irradiated on the surface layer portion of the subject. The excitation light coupled to the SMF 211 is confined in a core having a diameter of several μm, and the tip of the core of the SMF 211 from which the excitation light is emitted functions as a point light source (light source side pinhole) of the confocal optical system.

  The scan drive circuit 223 b of the XY axis actuator 223 generates an X axis drive voltage and a Y axis drive voltage based on a control signal from the scan control circuit 206. The X-axis drive voltage and the Y-axis drive voltage are AC voltages synchronized with the frame rate of the video signal output to the monitor 300. By applying the X-axis drive voltage and the Y-axis drive voltage to the main body 223a of the XY-axis actuator 223, the tip portion 211a of the SMF 211 (and the spot of the excitation light emitted from the tip portion 211a) is perpendicular to the Z-axis. The XY axis actuator 223 is driven so as to be scanned while drawing a predetermined locus on the plane. Strictly speaking, the tip of the SMF 211 (spot of excitation light) draws a scanning locus on the curved surface, but since the scanning width is sufficiently small with respect to the length of the tip portion 211a of the SMF 211, the tip of the SMF 211 (excitation light) Can be approximated to scanning on the XY plane perpendicular to the Z axis.

  By changing the waveforms of the X-axis drive voltage and the Y-axis drive voltage, the spot scanning trajectory can be variously changed. Examples of the two-dimensional scanning method include spiral scanning that scans a spiral trajectory centered on the central axis AX, raster scanning method that reciprocally scans the horizontal direction of the scanning range, and Lissajous scanning method that scans the scanning range sinusoidally. Various scanning methods can be employed.

  The movable frame 222 attached to the inner side of the inner cylinder 221b is a substantially cylindrical member having a hollow portion extending in the Z-axis direction, and is held coaxially with the inner cylinder 221b. An SMF 211 is passed through the hollow portion of the movable frame 222. The base end portion of the movable frame 222 protrudes from the opening on the base end side of the inner cylinder 221b, and a substantially cylindrical magnet 228b is attached to the outer peripheral surface thereof.

  When the inner cylinder 221b slides in the Z-axis direction within the outer cylinder 221a, the movable frame 222, the XY-axis actuator 223, the objective optical system 224, and the main body 223a of the XY-axis actuator 223 attached to the inner cylinder 221b are fixed. The distal end portion 211a of the SMF 211 is configured to move in the Z-axis direction together with the inner cylinder 221b.

  The fixed frame 226 and the Z-axis actuator 227 are accommodated inside the base end side of the outer cylinder 221a. The fixed frame 226 is a substantially cylindrical member having a hollow portion extending in the Z-axis direction. The fixed frame 226 has a rectangular cross-section opening 226a (FIG. 3) penetrating in the Y-axis direction. The opening 226a accommodates a substantially rectangular parallelepiped casing 227a of the Z-axis actuator 227 for fixing. It is fixed to the frame 226.

  A portion on the proximal end side of the movable frame 222 and a coil spring 222a are accommodated in a hollow portion on the distal end side of the fixed frame 226, and a portion on the proximal end side of the movable frame 222 is inserted into the coil spring 222a. . The coil spring 222a is sandwiched between a step 226f formed on the inner peripheral surface of the fixed frame 226 and a magnet 228b attached to the outer peripheral surface of the base end portion of the movable frame 222. The movable frame 222 is urged toward the base end side (Z-axis negative direction) via the magnet 228b by elastic force.

  A Hall element 228a is provided on the outer peripheral surface of the fixed frame 226 near the step 226f (coil spring 222a). The hall element 228a and the magnet 228b constitute a Z-axis position sensor 228 that detects the position of the drive shaft 227b of the Z-axis actuator 227.

  A substantially cylindrical drive shaft 227b that advances and retreats in the Z-axis direction protrudes from the front end surface of the housing 227a of the Z-axis actuator 227. The outer diameter of the drive shaft 227b is larger than the inner diameter of the movable frame 222, and the movable frame 222 is pushed to the proximal end side by the coil spring 222a as described above. Therefore, the distal end of the drive shaft 227 b of the Z-axis actuator 227 is in contact with the base end surface of the movable frame 222. When the drive shaft 227b moves back and forth in the Z-axis direction, the movable frame 222, the inner cylinder 221b fixed to the movable frame 222, the XY axis actuator 223, the objective optical system 224, and the tip end portion 211a of the SMF 211 are driven. Along with the shaft 227b, it moves forward and backward in the Z-axis direction in the outer cylinder 221a. As a result, the distance from the window 221c to the excitation light spot (that is, the depth from the surface of the subject to which the window 221c is pressed to the excitation light spot) changes, and therefore the confocal light is driven by driving the Z-axis actuator 227. The depth of the scanning surface (that is, the observation surface) of the scanning optical unit 220 can be adjusted.

  The scanning control circuit 206 controls the drive of the Z-axis actuator 227 so that the position of the drive shaft 227b of the Z-axis actuator 227 detected by the Z-axis position sensor 228 becomes a set value designated by the CPU 202, and outputs a control signal. The signal is transmitted to the circuit board 230 on which the Z-axis drive circuit is mounted by the shield cable 212a. The Z-axis drive circuit generates drive power based on the control signal from the scanning control circuit 206 and supplies it to the Z-axis actuator 227. Thereby, the observation depth of the confocal scanning optical unit 220 is adjusted.

  The Z-axis actuator 227 (the housing 227a and the drive shaft 227b) is also formed with a through hole (not shown) extending in the Z-axis direction and connected to the hollow portion of the fixed frame 226. The SMF 211 passes through the hollow portions (or through holes) of the fixed frame 226, the Z-axis actuator 227, the movable frame 222, and the XY-axis actuator 223 in order from the base end side.

  The outer peripheral surface of the fixed frame 226 is D-cut by two planes that are parallel to the Z-axis direction and parallel to each other, leaving the base end portion, and two D-cut surfaces (hereinafter referred to as “upper surface” and “lower surface”). ") Is formed. Therefore, wall portions 226b and 226d protruding from the plane formed on the upper surface and the lower surface are formed at the base end portion of the remaining fixed frame 226.

  The distance between the upper surface and the lower surface of the fixed frame 226 is the same as the distance between the upper surface and the lower surface (two surfaces perpendicular to the Y axis) of the Z-axis actuator 227. The Z-axis actuator 227 is accommodated in the opening 226a of the fixed frame 226 so that the housing 227a does not protrude from the upper surface and the lower surface of the fixed frame 226. The casing 227a is integrally fixed to the fixed frame 226, and functions as a part of the fixed frame 226 (a support member that supports a circuit board 230 described later) as described later.

  Shield cables 212 a and 212 b are connected to the base end portion of the confocal scanning optical unit 220. FIG. 3 is a perspective view showing a schematic structure of a connection portion between the confocal scanning optical unit 220 and the shield cable 212a, as viewed from the upper surface side of the housing 227a. As shown in FIG. 3, a V-shaped notch 226c is formed at the center of the wall 226b in the X-axis direction. One end of the shielded cable 212a is positioned and supported at the center of the confocal scanning optical unit 220 in the X-axis direction by a notch 226c. Further, the sheath of the shielded cable 212a is fixed to the fixed frame 226 with an adhesive 226e at the notch 226c.

  The shielded cable 212a is formed by twisting a plurality of wires 212w (only five are shown in FIG. 3) and covering them with a braided shield 212s and further covering with a sheath. The shield cable 212a has a sheath removed in the confocal scanning optical unit 220 (on the tip side from the adhesive fixing portion), the braided shield 212s is released, and the wire 212w is exposed. The braided shield 212s once untwisted is twisted into a rod shape and then heated to soak up solder. The flexibility of the braided shield 212s is lost due to the solder, and the shape is fixed.

  A circuit board 230 on which a Z-axis drive circuit is mounted is attached to the upper surface (side surface on the Y-axis positive direction side) of the housing 227a of the Z-axis actuator 227. The circuit board 230 is provided with a plurality of wiring patterns, and solder lands 230p, 230q, and 230r are provided on the front surface (the surface opposite to the back surface attached to the housing 227a). Only one solder land (ground pattern) 230 p that is elongated in the Z-axis direction is formed at the center in the width direction (X-axis direction) on the base end side of the circuit board 230. A plurality of circular solder lands 230q (only five are shown in FIG. 3) are arranged along the solder lands 230p on both sides of the solder lands 230p. A plurality of circular solder lands 230r (only three are shown in FIG. 3) are arranged along the edge on the front end side of the circuit board 230. A braided shield 212s twisted in a rod shape is connected to the solder land 230p by solder. In addition, a plurality of wires 212w of the shield cable 212a are connected to the plurality of solder lands 230q by solder. A plurality of wires 227w (only three are shown in FIG. 3) drawn from the Z-axis actuator 227 are connected to the plurality of solder lands 230r by solder. Further, a sealing material 230s is applied to each solder connection portion and sealed. In addition, you may use the adhesive agent used for the assembly of the confocal scanning optical unit 220 as the sealing material 230s.

  FIG. 4 is a cross-sectional view of the assembled confocal scanning optical unit 220 cut along the vicinity of the base end of the circuit board 230. As shown in FIG. 4, since the space between the upper surface of the circuit board 230 and the cover 229 is widest in the center in the width direction (X-axis direction) of the circuit board 230, the braided shield 212s having the thickest diameter is provided at this position. It is arranged. As a result, the braided shield 212s is less likely to interfere with the cover 229, so that the inner diameter of the cover 229 can be reduced and the confocal scanning optical unit 220 can be further reduced in diameter.

  Further, as described above, the elongated solder land 230p for connecting the braided shield 212s is arranged along the central axis of the shield cable 212a, so that the twisted braided shield 212s is straightened without being bent. Since the braided shield 212s is fixed, the residual braided shield 212s does not have a large residual stress, and the peeling of the solder is prevented, thereby improving the reliability of the solder connection portion.

  Also, instead of connecting only the wire to the distal end of the endoscope after peeling off the sheath and braided shield at the distal end of the shielded cable as in the past, the part having a complete cable structure as described above The structure in which the braided shield 212s and the highly rigid portion covered by the sheath are supported by the notch 226c of the fixed frame 226, even if a strong force is applied to the shield cable 212a, the exposed thin wire 212w The force is not transmitted and disconnection of the wire 212w is prevented.

  Similarly to the wall 226b, a V-shaped notch (not shown) is formed in the wall 226d, and the shield cable 212b is held at a predetermined position by the notch. The wire of the shielded cable 212b is soldered to a solder land (not shown) provided at one end of an FPC (Flexible printed circuits) 212f. The other end of the FPC 212f is connected to the scan driving circuit 223b.

  Next, a part of the assembly procedure of the confocal scanning optical unit 220 (specifically, the procedure of connecting the shield cable 212a to the confocal scanning optical unit 220) will be described with reference to FIG.

  First, as shown in FIG. 5A, the sheath having a predetermined length is peeled off from the tip of the shielded cable 212a, the braided shield 212s is released to expose the wire 212w, and the braided shield 212s is twisted into a rod shape. Next, the braided shield 212s twisted in a rod shape is heated to soak the solder and fix the shape. Then, the bar-shaped braided shield 212s is soldered along the solder land 230p of the circuit board 230.

  Next, as shown in FIG. 5B, the plurality of wires 212w of the shield cable 212a are soldered to the corresponding solder lands 230q.

  Next, as shown in FIG. 5C, the circuit board 230 is fixed to the upper surface of the housing 227a of the Z-axis actuator 227, and a plurality of wires 227w drawn from the Z-axis actuator 227 are respectively connected to the corresponding solder lands. Secure to 230r with solder.

  Next, as shown in FIG. 5D, a sealant 230s is applied to the solder connection portion.

  Next, as shown in FIG. 5E, the integrated Z-axis actuator 227, circuit board 230, and shield cable 212 a are attached to the fixed frame 226. At this time, the shield cable 212a is supported by the notch 226c of the fixed frame 226.

  Next, as shown in FIG. 5 (f), an adhesive 226 e is applied to the notch 226 c to fix the shield cable 212 a to the fixed frame 226.

  Then, as shown in FIG. 5G, the assembled confocal scanning optical unit 220 is housed and fixed in a cylindrical cover 229, whereby the assembly of the confocal scanning optical unit 220 is completed.

  As described above, by fixing the braided shield 212s having high rigidity to the circuit board 230 first, the positional relationship between the shield cable 212a and the circuit board 230 is stabilized, so that the ultrafine wire 212w is attached to the circuit board 230. At the time of attachment, the risk that the positional relationship between the shielded cable 212a and the circuit board 230 changes unexpectedly and an excessive stress is applied to the wire 212w is greatly reduced.

  The above is the description of the embodiment of the present invention. However, the present invention is not limited to the configuration of the above-described embodiment, and various modifications are possible within the scope of the technical idea.

  For example, the confocal probe 200 of the present embodiment is configured as a probe separate from the endoscope. However, in another embodiment, for example, as shown in FIG. The confocal observation system-integrated electronic endoscope 400 may be integrated into a endoscope (for example, an electronic endoscope including a light guide (not shown) and an imaging element 410 such as a CCD).

  The above embodiment is an example in which the present invention is applied to a scanning confocal endoscope, but the present invention is not limited to this configuration, and is applied to a non-confocal optical scanning endoscope apparatus. You can also. Further, the present invention can be applied not only to an endoscope apparatus but also to various treatment instruments for endoscopes (for example, an electric knife) and a catheter. Furthermore, the present invention is not limited to medical devices and can be applied to various industrial and consumer devices.

DESCRIPTION OF SYMBOLS 1 Scanning confocal endoscope apparatus 100 Processor 200 Confocal probe 206 Scan control circuit 210 Cable part 212a, 212b Shield cable 212s Braided shield 212w Wire 220 Confocal scanning optical unit 221 Housing 222 Movable frame 223 XY axis actuator 226 Fixed frame 227 Z-axis actuator 227w wire 230 circuit board 230p, 230q, 230r solder land 300 monitor

Claims (10)

An optical scanning endoscope including a scanning optical unit that vibrates a free end of an optical fiber supported in a cantilever manner and periodically scans illumination light emitted from the free end on a subject,
The scanning optical unit includes:
A fiber driving unit that is provided near the free end of the optical fiber and presses and bends the side surface of the optical fiber;
A fiber moving means for moving the fiber drive unit along the longitudinal direction of the optical fiber to move the free end of the optical fiber along the longitudinal direction of the optical fiber;
It has a plurality of wiring patterns electrically connected to at least one of the fiber driving unit and the fiber moving unit, and at least one of the fiber driving unit and the fiber moving unit via the plurality of wiring patterns A circuit board for supplying drive power for driving one of the circuits;
With
The optical scanning endoscope is:
A control circuit for generating a control signal for controlling the supply of the driving power by the circuit board;
A shielded cable having a plurality of electric wires for transmitting the control signal from the control circuit to the circuit board, and a braided shield for shielding the plurality of electric wires;
With
The circuit board is arranged in parallel with the longitudinal direction of the optical fiber so that the back surface side faces the optical fiber, and a plurality of signals for soldering the plurality of electric wires to the plurality of wiring patterns on the front surface side A solder land and a grounding solder land for soldering the braided shield, and the braided shield is soldered to the grounding solder land along the surface of the circuit board, and then the plurality An optical scanning endoscope characterized in that a plurality of electric wires are soldered to the plurality of signal solder lands.   2. The optical scanning mold according to claim 1, wherein a sheath is removed from a distal end portion of the shielded cable, and the exposed braided shield is twisted in a rod shape and fixed in shape by solder. Endoscope.   The grounding solder land extends in a longitudinal direction of the optical fiber, and the signal solder land is disposed on both sides of the grounding solder land. The described optical scanning endoscope. The scanning optical unit has a substantially cylindrical support member that supports the fiber driving unit, the fiber moving means, and the circuit board,
4. The optical scanning endoscope according to claim 1, wherein a surface of the circuit board is exposed on an outer peripheral surface of the support member. 5.   The optical scanning endoscope according to claim 4, wherein a notch portion that holds the shield cable in a predetermined position is formed at a base end portion of the support member. This is an assembly method of an optical scanning endoscope having a scanning optical unit at the tip thereof that vibrates the free end of the cantilevered optical fiber and periodically scans the illumination light emitted from the free end on the subject. And
A circuit board on which a plurality of control signal wiring patterns and a ground pattern are formed to control driving of the scanning optical unit, a plurality of electric wires transmitting a control signal for controlling driving of the scanning optical unit, and , Arranged along the longitudinal direction of a shielded cable having a braided shield for shielding the plurality of electric wires, soldering the braided shield at the tip of the shielded cable to the ground pattern, and then a signal at the tip of the shielded cable Soldering a line to each of the wiring patterns;
Accommodating the circuit board connected to the shielded cable in a support member of the scanning optical unit;
The circuit board is provided in the vicinity of a free end of the optical fiber, and a fiber driving unit that presses and bends the side surface of the optical fiber, or the fiber driving unit is moved along the longitudinal direction of the optical fiber. Electrically connecting the free end of the optical fiber to a fiber moving means for advancing and retreating along the longitudinal direction of the optical fiber;
Bonding and fixing the shielded cable to the support member;
A method for assembling an optical scanning endoscope, comprising: The step of soldering the braided shield to the ground pattern includes:
Removing the sheath at the tip of the shielded cable to expose the braided shield;
Unwinding the braided shield and exposing the signal line housed in the braided shield;
Twisting the braided shield into a rod shape;
Heating the braided shield twisted in a rod shape and soaking the solder,
The method of assembling an optical scanning endoscope according to claim 6. After the step of soldering the signal line at the tip of the shielded cable to the wiring pattern, applying a sealing material to the soldered part;
The method of assembling an optical scanning endoscope according to claim 6 or 7, further comprising:   The ground pattern is formed so as to extend substantially in the center of the circuit board in the longitudinal direction of the shielded cable, and the plurality of wiring patterns are formed on both sides of the ground pattern. The method for assembling an optical scanning endoscope according to any one of claims 6 to 8. Prior to the step of electrically connecting the circuit board to the fiber driver or fiber moving means, further comprising the step of attaching the circuit board to the fiber driver or fiber moving means;
2. The step of accommodating the circuit board in a support member of the scanning optical unit, wherein the fiber driving unit or fiber moving means to which the circuit board is attached is accommodated in the support member. The method for assembling an optical scanning endoscope according to any one of claims 6 to 9.

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