JP2009232960A - Optical probe device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent injury within a sheath by retaining the position of an optical housing within the sheath of an optical probe device and inhibiting the contact between the housing and the sheath. <P>SOLUTION: The optical probe device obtains an optical tomographic image by using interfering light. The optical probe device comprises the tubular sheath whose distal end side at least is transparent and flexible; an interfering-light outgoing/incoming part disposed in the inner lumen of the sheath; the housing for holding the interfering light outgoing/incoming part; a flexible shaft connected to the housing for transmitting the rotation to the housing by a driving means at the rear end; and position retaining means disposed at the distal end of a member for occluding the distal end of the sheath and at the distal end of the housing for retaining the position of the housing. The position retaining means also serves as a friction preventing means for preventing the friction between the inner surface of the member for occluding the distal end of the sheath and the distal end of the housing when the housing is rotated. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an optical probe apparatus, and more particularly, to an optical probe apparatus that is used in an optical tomographic imaging apparatus that acquires an optical tomographic image using interference light and that is inserted into a body cavity and performs measurement.

  Conventionally, as an endoscope apparatus for observing the inside of a body cavity of a living body, an electronic endoscope apparatus that captures an image of reflected light reflected in the body cavity of a living body irradiated with illumination light and displays the image on a monitor or the like is widely spread. And used in various fields. Many endoscope apparatuses include a forceps port, and a biopsy or treatment of a tissue in the body cavity can be performed with a probe introduced into the body cavity via the forceps port.

  On the other hand, in recent years, development of a tomographic image acquisition apparatus that acquires a tomographic image of a living body and the like without cutting a measurement target such as a living tissue has been advanced. For example, optical coherence tomography (OCT) using interference by low-coherence light has been developed. An optical tomographic imaging apparatus using an optical coherence tomography measurement method is known. An optical tomographic imaging apparatus using this OCT measurement method divides low-coherence light emitted from a light source composed of an SLD (Super Luminescent Diode) or the like into signal light and reference light, and uses reference light or signal light by a piezo element or the like. The signal light is incident on the measurement unit, the reflected light reflected at a predetermined depth of the measurement unit is interfered with the reference light, and the light intensity of the interference light is measured by heterodyne detection. The tomographic information is acquired, and the optical path length of the reference light and the optical path length of the signal light are changed by slightly moving a movable mirror arranged on the optical path of the reference light and slightly changing the optical path length of the reference light. The matched information at the depth of the measurement unit can be obtained. Further, by repeating the measurement while slightly shifting the incident point of the signal light, an optical tomographic image of a predetermined scanning region can be acquired.

  Using such an OCT apparatus (optical tomographic imaging apparatus), an OCT probe (optical probe) is inserted into the forceps opening of the endoscope apparatus to guide the signal light and the reflected light of the signal light, and the light in the body cavity By acquiring a tomographic image, for example, it is possible to diagnose the depth of invasion of an initial cancer.

  In FIG. 5, the front-end | tip part of the conventional optical probe is expanded and shown.

  As shown in FIG. 5, a conventional optical probe 1010 includes a transparent sheath (probe outer cylinder) 1012, a tip cap 1014, an optical fiber FB0, a hemispherical lens 1016, a flexible shaft 1018, an exterior jacket 1020, A first sleeve 1022, a second sleeve 1024, and a ferrule 1026 are provided.

  The sheath 1012 is a cylindrical member that transmits light such as PTFE (polytetrafluoroethylene) and has flexibility. The distal end cap 1014 is formed of, for example, SUS303 or the like, and is fixed to the sheath 1012 by screwing and bonding, thereby closing the distal end side of the sheath 1012. The optical fiber FB0 is a linear member, is accommodated in the sheath 1012 along the sheath 1012, guides the measurement light from the optical rotary adapter (not shown) to the hemispherical lens 1016, and the measurement acquired by the hemispherical lens 1016. The return light from the object is guided to the optical rotary adapter. The hemispherical lens 1016 is disposed at the measurement-side distal end of the optical fiber FB0, and the distal end portion is formed in a substantially spherical shape for condensing the measurement light emitted from the optical fiber FB0 onto the measurement target.

  In addition, the flexible shaft 1018, the outer jacket 1020, the first sleeve 1022, the second sleeve 1024, and the ferrule 1026 hold the optical fiber FB0 rotatably in the sheath 1012. The flexible shaft 1018 is composed of a coil wound in a spiral shape, and freely rotates to transmit a rotational force. The ferrule 1026 has a function of holding and protecting the optical fiber FB0 by inserting the optical fiber FB0 through the core.

  Here, the flexible shaft 1018 is welded to the first sleeve 1022, the first sleeve 1022 is bonded to the second sleeve 1024, the second sleeve 1024 is bonded to the ferrule 1026, and the outer jacket 1020 is in the position of P at the ferrule 1026. It is glued to. As a result, the flexible shaft 1018 rotates as shown by an arrow R in the sheath 1012 as a unit.

  However, as shown in FIG. 5, the position of the rotating member including the optical fiber FB0 is not restricted. Therefore, when the rotating member rotates, the flexible shaft 1018 extends and the tip hemispherical lens 1016 contacts the tip cap 1014. There is a possibility that other members may come into contact with the inner wall of the sheath 1012 and be damaged during rotation.

  Therefore, in order to prevent such damage to the inner surface of the sheath, conventionally, for example, a friction preventing means for reducing friction during rotation of the housing such as a metal ball is provided between the sheath tip inner side and the optical tip housing. (See, for example, Patent Document 1).

As shown in FIG. 6, a metal sphere 1032 is partially embedded in the tip of the inner surface of the sheath 1030 so that the contact point 1034 of the metal sphere 1032 makes point contact with the tip surface 1038 of the tip housing 1036. As a result, the portion of the metal ball 1032 exposed from the inner surface tip of the sheath 1030 contacts the tip smooth surface of the tip housing 1036 at a point, so that the friction resistance of the tip housing 1036 is small, and the point contact point with the metal ball 1032 And a line connecting the center and the axis.
JP 2001-79007 A

  However, in the above conventional optical unit, the distance between the sheath and the tip housing changes due to bending or bending of the probe, and even if a gap fluctuation mitigation means such as a spring is inserted, this fluctuation may not be able to follow this fluctuation. On the contrary, there is a problem that the optical system itself is buckled by the spring and may come into contact with the inner surface of the housing. Moreover, since the friction preventing means described in Patent Document 1 does not regulate the position of the housing, it is insufficient for preventing scratches on the inner surface of the sheath.

  The present invention has been made in view of such circumstances, and can maintain the position of the optical housing within the sheath of the optical probe device and suppress contact between the two to prevent the occurrence of scratches in the sheath. An object is to provide a probe device.

  In order to achieve the above object, an invention according to claim 1 is an optical probe device that obtains an optical tomographic image using interference light, wherein at least a distal end side is transparent and has a flexible sheath, The interference light emitting / incident part provided in the sheath lumen, a housing holding the interference light emitting / incident part, and connected to the housing, and rotated by driving means at the rear end to the housing. A flexible shaft for transmitting; a member for closing the sheath tip; and a position holding means for holding the position of the housing, each provided at the tip of the housing; and the position holding means when the housing rotates Provided is an optical probe device characterized by also serving as friction preventing means for preventing friction between an inner surface of a member closing the tip and the tip of the housing. .

  As a result, the position of the housing of the optical system within the sheath can be maintained, and both can be prevented from coming into contact with each other, thereby preventing the inner surface of the sheath from being scratched and preventing rotational fluctuations due to increased rotational resistance. Is possible.

  Similarly, in order to achieve the above object, the invention according to claim 2 is an optical probe device that obtains an optical tomographic image using interference light, and has a cylindrical shape that is transparent at least at the tip side and is flexible. The interference light emitting / incident part provided in the lumen of the sheath, a housing holding the interference light emitting / incident part, a light guide and coupled to the housing, and a rear end An optical fiber that transmits rotation to the housing from the driving means of the part, a flexible shaft that is indirectly connected to the housing via the optical fiber, a member that closes the sheath tip, and a tip of the housing, respectively. Position holding means for holding the position of the housing, and the position holding means includes an inner surface of a member that closes the sheath tip when the housing rotates. To provide an optical probe device characterized by serving as a friction prevention means for preventing the friction between the serial distal housing.

  As a result, the position of the housing of the optical system within the sheath can be maintained, and both can be prevented from coming into contact with each other, thereby preventing the inner surface of the sheath from being scratched and preventing rotational fluctuations due to increased rotational resistance. Is possible.

  According to a third aspect of the present invention, the position holding means is configured so that a concave shape formed on a member that closes the sheath tip and a convex shape formed on the housing tip are rotatably fitted to each other. It is characterized by being formed.

  Thereby, the position of the housing of the optical system in the sheath can be maintained.

  According to a fourth aspect of the present invention, the position holding means is configured so that a convex shape formed on a member that closes the sheath tip and a concave shape formed on the housing tip are rotatably engaged with each other. It is characterized by being formed.

  Thereby, similarly, the position of the housing of the optical system within the sheath can be maintained.

  According to a fifth aspect of the present invention, the member that closes the sheath tip is formed of a metal member separate from the sheath, and is fixed to the sheath by bonding, screwing, or both bonding and screwing. It is characterized by that.

  Thereby, the strength and durability can be improved by forming the member that closes the sheath tip from the metal material.

  According to a sixth aspect of the present invention, a concave shape is formed by press-fitting or screwing a resin member into a metal member that forms a member for closing the sheath tip.

  Thereby, the low friction property of the bearing which receives the convex shape of the housing front-end | tip by forming with a resin member is securable.

  According to a seventh aspect of the present invention, the resin member is a fluororesin or a low wear and high slidable material.

  Thereby, the abrasion property of the bearing which receives the convex shape of the housing front end can be formed low.

  In addition, according to an eighth aspect of the present invention, the member for closing the sheath tip and the sheath are formed as separate bodies of the same material, and each is integrally joined by heat welding.

  Thereby, while improving the sealing performance of the member which obstruct | occludes a sheath front end, and the safety | security and durability with respect to drop-off, cost reduction can be aimed at.

  According to a ninth aspect of the present invention, the member for closing the sheath tip and the material of the sheath are tetrafluoroethylene perfluoroalkoxyethylene copolymers.

  Thereby, it becomes possible to freely process due to the properties as a thermoplastic resin that can be melt-molded, and it is possible to further improve the low friction of the fitting portion.

  According to a tenth aspect of the present invention, the position holding means regulates the position in the housing distal end side direction by applying an inner surface of a member that closes the distal end of the housing and an inner surface of the sheath.

  As a result, the position of the housing in the thrust direction can be reliably controlled while reducing the surface pressure.

  The fitting length between the concave shape formed in the member closing the sheath tip constituting the position holding means and the convex shape formed at the housing tip is defined by the thrust of the housing. It is characterized by being larger than the amount of movement.

  Thereby, it is possible to prevent the optical housing from contacting the inner surface of the sheath and damaging the concave shape formed in the member closing the sheath tip and the convex shape formed at the housing tip.

  As described above, according to the present invention, the position of the housing of the optical system within the sheath can be maintained, and both can be prevented from coming into contact with each other, thereby preventing damage on the inner surface of the sheath and rotating. It is possible to prevent rotational fluctuation due to increased resistance.

  Hereinafter, an optical probe device according to the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a block diagram showing a schematic configuration of an optical tomographic imaging apparatus in which the optical probe apparatus according to the first embodiment of the present invention is used.

  An optical tomographic imaging apparatus 10 of the present invention shown in FIG. 1 is for acquiring an optical tomographic image of a measurement object by an optical coherence tomography (OCT) measurement method, and emits light La for measurement. Light source (light source unit) 12 and the light La emitted from the light source 12 are branched into the measurement light L1 and the reference light L2, and the return light L3 and the reference light L2 from the measurement target S that is the subject are combined. And an optical fiber coupler (branching / combining unit) 14 that generates interference light L4 and L5, and the measurement light L1 branched by the optical fiber coupler 14 is guided to the measurement target and the return light L3 from the measurement target is guided. An optical probe (optical probe device) 16 including a rotating optical fiber FB1 and a return light L3 that guides the measuring light L1 to the rotating optical fiber FB1 and is guided by the rotating optical fiber FB1. A fixed-side optical fiber FB2 that guides light, a rotary-side optical fiber FB1 rotatably connected to the fixed-side optical fiber FB2, an optical rotary adapter 18 that transmits the measurement light L1 and the return light L3, and an optical fiber coupler. The interference light detection unit 20 that detects the interference lights L4 and L5 generated at 14 as interference signals, and processes the interference signal detected by the interference light detection unit 20 to produce an optical tomographic image (hereinafter simply referred to as “tomographic image”). A processing unit 22 that acquires the tomographic image acquired by the processing unit 22, and a display unit 24 that displays the tomographic image acquired by the processing unit 22.

  The optical tomographic imaging apparatus 10 also combines the optical path length adjustment unit 26 that adjusts the optical path length of the reference light L2, the optical fiber coupler 28 that splits the light La emitted from the light source 12, and the optical fiber coupler 14. Detection units 30a and 30b that detect the returned lights L4 and L5, respectively, and an operation control unit 32 that inputs various conditions to the processing unit 22 and the display unit 24, changes settings, and the like.

  As will be described later, in the optical tomographic imaging apparatus 10 shown in FIG. 1, various lights including the above-described emission light La, measurement light L1, reference light L2, return light L3, and the like are transmitted between components such as optical devices. Various optical fibers FB (FB3, FB4, FB5, FB6, FB7, etc.) including the rotation-side optical fiber FB1 and the fixed-side optical fiber FB2 are used as light paths for guiding and transmitting in FIG.

  The light source 12 emits OCT signal light (for example, laser light having a wavelength of 1.3 μm). For example, the light source 12 is emitted from an SLD (Super Luminescent Diode) 12a that emits low-coherence light La and the SLD 12a. And a lens 12b that collects the low-coherent light La. The light La emitted from the light source 12 is input to the optical fiber coupler 14 via the optical fibers FB4 and FB3.

    The optical fiber coupler (branching / combining unit) 14 is composed of, for example, a 2 × 2 optical fiber coupler, and is optically connected to the optical fiber FB2, the optical fiber FB3, the optical fiber FB5, and the optical fiber FB7, respectively. .

  The optical fiber coupler 14 splits the light La incident from the light source 12 via the optical fibers FB4 and FB3 into the measurement light L1 and the reference light L2. The measurement light L1 is input to the optical rotary adapter 18 via the optical fiber FB2, and the reference light L2 is input to the optical path length adjustment unit 26 via the optical fiber FB5. .

  Furthermore, the optical fiber coupler 14 is obtained by the optical probe 16 reflected by the measurement object S and the light L2 returned from the optical fiber FB5 after the frequency shift and the optical path length are changed by the optical path length adjusting unit 26 as will be described later. Then, the return light L3 guided from the optical fiber 1 and the optical fiber FB2 is multiplexed and emitted to the optical fiber FB3 (FB6) and the optical fiber FB7.

  The optical probe 16 is connected to the optical fiber FB2 via the optical rotary adapter 18. The measurement light L1 is input from the optical fiber FB2 to the optical fiber FB1 in the optical probe 16 through the optical rotary adapter 18. The input measurement light L1 is transmitted through the optical fiber FB1 and irradiated onto the measurement object S. Then, the optical probe 16 acquires the return light L3 reflected by the measuring object S, transmits the acquired return light L3 through the optical fiber FB1, and emits it to the optical fiber FB2 through the optical rotary adapter 18. It has become.

  The optical rotary adapter 18 optically connects the fixed optical fiber FB2 and the optical fiber FB1 rotating in the optical probe 16 (described in detail later).

  The interference light detection unit 20 is connected to the optical fibers FB6 and FB7, and uses the interference lights L4 and L5 generated by combining the reference light L2 and the return light L3 by the optical fiber coupler 14 as interference signals. It is to detect.

  Here, the optical tomographic imaging apparatus 10 is provided on an optical fiber FB6 branched from the optical fiber coupler 28, and a detector 30a that detects the light intensity of the laser light L4 and interference light on the optical path of the optical fiber FB7. And a detector 30b for detecting the light intensity of L5.

  The interference light detection unit 20 adjusts the balance of the intensity of the interference light L4 detected from the optical fiber FB6 and the intensity of the interference light L5 detected from the optical fiber FB7 based on the detection results of the detectors 30a and 30b.

  From the interference signal detected by the interference light detection unit 20, the processing unit 22 is a region where the optical probe 16 and the measurement target S are in contact at the measurement position, more precisely, a probe outer cylinder (sheath, which will be described later) of the optical probe 16. ) And the surface of the measuring object S are detected, and a tomographic image is acquired from the interference signal detected by the interference light detection unit 20.

  The display unit 24 includes a CRT or a liquid crystal display device, and displays the tomographic image transmitted from the processing unit 22.

  The optical path length adjustment unit 26 is disposed on the emission side of the reference light L2 of the optical fiber FB5 (that is, the end of the optical fiber FB5 opposite to the optical fiber coupler 14).

  The optical path length adjustment unit 26 includes a first optical lens 40 that converts the light emitted from the optical fiber FB5 into parallel light, a second optical lens 42 that condenses the light converted into parallel light by the first optical lens 40, and The reflection mirror 44 that reflects the light collected by the second optical lens 42, the base 46 that supports the second optical lens 42 and the reflection mirror 44, and the base 46 are moved in a direction parallel to the optical axis direction. The optical path length of the reference light L2 is adjusted by changing the distance between the first optical lens 40 and the second optical lens 42.

  The first optical lens 40 converts the reference light L2 emitted from the core of the optical fiber FB5 into parallel light, and condenses the reference light L2 reflected by the reflection mirror 44 on the core of the optical fiber FB5.

  The second optical lens 42 condenses the reference light L2 converted into parallel light by the first optical lens 40 on the reflection mirror 44, and makes the reference light L2 reflected by the reflection mirror 44 parallel light. Thus, the first optical lens 40 and the second optical lens 42 form a confocal optical system.

  Further, the reflection mirror 44 is disposed at the focal point of the light collected by the second optical lens 42, and reflects the reference light L <b> 2 collected by the second optical lens 42.

  As a result, the reference light L2 emitted from the optical fiber FB5 becomes parallel light by the first optical lens 40 and is condensed on the reflection mirror 44 by the second optical lens. Thereafter, the reference light L2 wave reflected by the reflection mirror 44 becomes parallel light by the second optical lens 42, and is condensed by the first optical lens 40 on the core of the optical fiber FB5.

  The base 46 fixes the second optical lens 42 and the reflection mirror 44, and the mirror moving mechanism 48 moves the base 46 in the optical axis direction of the first optical lens 40 (direction of arrow A in FIG. 1). .

  The distance between the first optical lens 40 and the second optical lens 42 can be changed by moving the base 46 in the direction of arrow A with the mirror moving mechanism 48, and the optical path length of the reference light L2 can be adjusted. Can do.

  The operation control unit 32 includes input means such as a keyboard and a mouse, and control means for managing various conditions based on input information, and is connected to the processing unit 22 and the display unit 24. The operation control unit 32 inputs, sets and changes various processing conditions in the processing unit 22 and changes the display setting of the display unit 24 based on an operator instruction input from the input unit.

  Note that the operation control unit 32 may display an operation screen on the display unit 24, or may provide a separate display unit to display the operation screen. In addition, the operation control unit 32 controls the operation of the first light source 12, the second light source 13, the optical rotary adapter 18, the interference light detection unit 20, the optical path length, the detection units 30a and 30b, and sets various conditions. It may be.

  Next, the optical probe 16 will be described.

  FIG. 2 is an enlarged partial cross-sectional view showing the distal end portion of the optical probe 16 according to the first embodiment of the present invention.

  As shown in FIG. 2, the optical probe 16 of the first embodiment includes a probe outer tube (hereinafter referred to as a sheath) 50, a cap 52, an optical fiber FB1, a flexible shaft 54, a first sleeve 56, a second sleeve 58, A ferrule 60 and a hemispherical lens 62 are included.

  The sheath 50 is a flexible cylindrical member, and is reflected by the measurement light L1 and the measurement target S that are guided from the optical fiber FB1 and emitted from the hemispherical lens 62 toward the measurement target S (see FIG. 1). It is made of a material through which the returned light L3 is transmitted. In addition, the sheath 50 should just be formed with the material (transparent material) which permeate | transmits light over the perimeter part through which the measurement light L1 and the return light L3 pass.

  The cap 52 is a member that is provided at the distal end of the sheath 50 and closes the distal end of the sheath 50. The cap 52 and the sheath 50 are formed of different materials, and the cap 52 has a structure in which the cap 52 is coupled to the sheath 50 by bonding or screwing or both. For example, the cap 52 can be SUS, the sheath 50 can be PTFE (polytetrafluoroethylene), and an epoxy resin can be used as an adhesive.

  The optical fiber FB1 is a linear member, and is accommodated in the sheath 50 along the sheath 50, and the measurement light L1 guided from the optical fiber FB2 through the optical rotary adapter 18 is transmitted to the hemispherical lens 62 (interference light). The measurement light L1 irradiated to the measurement target S from the hemispherical lens 62 is reflected by the measurement target S, and the return light L3 acquired by the hemispherical lens 62 is guided to the optical rotary adapter 18. The wave is incident on the optical fiber FB2.

  Here, the optical fiber FB1 and the optical fiber FB2 are connected by the optical rotary adapter 18 as shown in FIG. 1, and are optically connected in a state where the rotation of the optical fiber FB1 is not transmitted to the optical fiber FB2. Yes. The optical fiber FB1 is disposed so as to be rotatable with respect to the sheath 50.

  The flexible shaft 54 has an optical fiber FB1 inserted therein and is spirally wound (a double coil is shown in the figure, but the present invention is not limited to this, and a triple coil may be used. ) To freely rotate and transmit the rotational force.

  The first sleeve 56, the second sleeve 58, and the ferrule 60 are members for fixing the optical fiber FB1. In particular, the ferrule 60 is a member for fixing and protecting the optical fiber FB1 on the innermost side in the sheath 50. The flexible shaft 54 is welded to the first sleeve 56, the first sleeve 56 is bonded to the second sleeve 58, and the ferrule 60 is bonded to the second sleeve 58.

  The flexible shaft 54 is rotationally driven by a rotational driving means (not shown), and the driving force is transmitted to the optical fiber FB1 via the first sleeve 56, the second sleeve 58, and the ferrule 60. As a result, the hemispherical lens 62 and the light The optical system including the fiber FB1 and the like is rotated as a whole in the sheath 50.

  The second sleeve 58 extends to the distal end side, and the distal end side is a cylindrical housing 64 that covers the hemispherical lens 62. The housing 64 is provided with an opening 64 a serving as an optical path for the measurement light L <b> 1 emitted from the hemispherical lens 62 and the return light L <b> 3 incident on the hemispherical lens 62.

  The housing 64 closes its tip, and a convex portion 66 is formed at the center (center of the cylinder) so as to extend further toward the tip of the optical probe 16. On the other hand, the cap 52 is formed with a concave portion 52 a that receives the convex portion 66 of the housing 64. Further, a bush (bushing) 68 serving as a bearing of an optical system rotating within the sheath 50 is provided in the recess 52a by press-fitting or screwing. When the bush 68 is installed by screwing, the screwing direction is opposite to the rotation direction of the optical system so as not to loosen.

  The bush 68 is made of a low-abrasion material such as PTFE (polytetrafluoroethylene) or ultrahigh molecular weight polyethylene (UHMW-PE) in order to reduce the frictional resistance with the rotating housing 64. used.

  The flexible shaft 54 is formed of a coil spring as described above, and expands and contracts by rotation. Thereby, the housing 64 and its convex part 66 move in the thrust direction (pressing direction) indicated by the arrow B in FIG. At this time, the movement in the thrust direction B is regulated by the flange portion (front end side surface) of the housing 64 abutting against the bush 68 as indicated by the symbol D in FIG. Further, at this time, the front end of the convex portion 66 is configured to have a certain gap so that the front end of the convex portion 66 does not hit the bottom of the concave portion 52 a of the cap 52.

  Further, with respect to the pulling direction C, the housing 64 is moved in the C direction so that the convex portion 66 does not come out of the bush 68 formed in the concave portion 52a of the cap 52 so as to prevent dropping. The fitting length d is configured to be larger than the moving amount of 64.

  As described above, the convex portion 66 is provided at the center of the front end of the housing 64, and the convex portion 66 is inserted into the concave portion 52a formed in the cap 52 and received by the bush (bearing) 68, thereby restricting the rotational position. In the thrust direction B, the front end side surface (flange portion) around the convex portion 66 at the front end of the housing 64 is brought into contact with the end surface of the bearing member (bush 68) provided on the member (cap 52) that closes the sheath front end. In this way, the position restriction in the pressing direction is performed.

  Further, by increasing the fitting length d of the convex portion 66 of the housing 64 and the concave portion 52a of the cap 52 than the variation length of the housing 64 (optical system) in the extraction direction C, the housing 64 varies in the extraction direction C. In this case, it is possible to prevent the fitting from being released and the housing 64 from contacting the inner surface of the sheath 50 to damage the inner surface of the sheath 50.

  Contrary to the above, a recess may be provided in the center of the front end of the housing 64, a protrusion may be formed on the cap 52, and these may be fitted to produce the same effect as described above. .

  Next, the operation of this embodiment will be described.

  The optical probe 16 is inserted into the body cavity of the subject, the tip side of the optical probe 16 where the hemispherical lens 62 exists is positioned at the observation site of the measurement object S, and the measurement light L1 is emitted from the hemispherical lens 62 toward the observation site. To do. At this time, by moving the base 46 in the direction of arrow A by the mirror moving mechanism 48 of the optical path length adjusting unit 26 shown in FIG. 1, the optical path length is adjusted so that the observation site of the measuring object S is located in the measurable region. Adjust and set. Then, light La is emitted from the light source 12. The emitted light La is split by the optical fiber coupler 14 into measurement light L1 and reference light L2. The measuring light L1 is guided from the optical fiber FB2 to the optical fiber FB1 through the optical rotary adapter 18.

  The flexible shaft 54 in FIG. 2 is rotated by a rotation driving unit (not shown). The rotational force of the flexible shaft 54 is transmitted from the first sleeve 56 to the second sleeve 58 (housing 64) and from the second sleeve 58 to the ferrule 60, and the optical fiber FB1 and the hemispherical lens 62 rotate.

  Thereby, the measurement light L1 emitted from the hemispherical lens 62 is irradiated over the entire circumference of the measurement target S, and the inside of the body cavity in which the optical probe 16 is inserted is optically scanned radially. Then, the return light L3 reflected at each position of the observation site enters the hemispherical lens 62, and is guided from the optical fiber FB1 to the optical fiber FB2 through the optical rotary adapter 18.

  The return light L3 guided to the optical fiber FB2 is combined with the reference light L2 guided by the optical fiber FB5 after the optical path length is adjusted by the optical path length adjustment unit 26 in the optical fiber coupler 14. Then, the return light L3 and the reference light L2 are combined to generate interference lights L4 and L5.

  The interference lights L4 and L5 are detected as interference signals by the interference light detection unit 20. The detected interference signal is sent to the processing unit 22. When the processing unit 22 acquires the transmitted interference signal, the processing unit 22 acquires information on the measurement position detected by the optical rotary adapter 18 and associates the interference signal with the position information on the measurement position.

  The processing unit 22 generates a tomographic image of the measurement target S from the interference signal and the position information of the measurement position, and performs image processing such as image quality correction processing. Then, the tomographic image subjected to the image processing is displayed on the display unit 24.

  As described above, in this embodiment, the convex portion 66 provided at the center of the distal end portion of the housing 64 of the optical system is fitted into the concave portion 52 a and the bush (bearing) 68 provided in the cap 52 at the distal end of the sheath 50. As a result, the position of the optical system in the rotational direction is regulated, and the flange part around the convex part 66 of the housing 64 is abutted against the bush 68 to regulate the position in the thrust direction B.

  Thereby, the position of the housing 64 of the optical system in the sheath 50 can be maintained, and both can be prevented from coming into contact with each other, so that the sheath 50 can be prevented from being damaged. Further, since the fitting length between the convex portion 66 at the distal end of the housing 64 and the concave portion 52a of the cap 52 is made larger than the moving length in the thrust direction of the housing 64 of the optical system, the fitting is released and the housing 64 is removed from the sheath 50. It is possible to prevent damage from contact with the inner surface.

  Further, the rotation fluctuation due to the increase in the rotational resistance by making the bush 68 as a bearing a low-wear and high-sliding material such as a fluororesin such as PTFE (polytetrafluoroethylene) or ultrahigh molecular weight polyethylene (UHMW-PE). Can be prevented.

  Next, a second embodiment of the present invention will be described.

  FIG. 3 is an enlarged partial cross-sectional view showing the tip of the optical probe according to the second embodiment of the present invention.

  As shown in FIG. 3, the optical probe 216 of this embodiment has substantially the same structure as the optical probe 16 of the first embodiment described above. The optical probe 216 of this embodiment is different from the optical probe 16 of the first embodiment in that both the cap 52 'and the sheath 50 are the same as PFA (tetrafluoroethylene / perfluoroalkoxyethylene copolymer) in this embodiment. This is because the cap 52 'and the sheath 50 are integrally bonded by heat welding at a portion indicated by symbol E in the figure. PFA (tetrafluoroethylene / perfluoroalkoxyethylene copolymer) used as a material for the cap 52 ′ and the sheath 50 is a thermoplastic resin and has an excellent low friction property. Therefore, in this embodiment, the cap 52 ′ itself Thus, the bush 68 installed as a bearing in the first embodiment can be made unnecessary.

  Thus, in this embodiment, since the sheath 50 and the cap 52 ′ at the tip thereof are formed of the same material (PFA) and are integrated by thermal welding, the sealing performance, the safety against cap removal and the durability are eliminated. In addition, the cost can be reduced.

  Since the configuration other than the above is the same as that of the first embodiment described above, a detailed description thereof will be omitted.

  Next, a third embodiment of the present invention will be described.

  FIG. 4 is an enlarged partial cross-sectional view showing the tip of the optical probe according to the third embodiment of the present invention.

  This embodiment is different from the first and second embodiments described above in the optical system driving method. That is, in the first and second embodiments described above, the housing that holds the tip optical system is driven via the rotatable flexible shaft. In the third embodiment, however, the tip optical system is held. The driving force for rotating the housing is transmitted via the optical fiber.

  The optical probe 316 of the present embodiment shown in FIG. 4 is basically obtained by changing the driving method of the optical probe 216 of the second embodiment described above.

  In the optical probe 316 of FIG. 4, the optical fiber FB1 is bonded to an exterior jacket 70 formed of PTFE. The outer jacket 70 is bonded to the first sleeve 56 at a position indicated by reference numeral F in FIG. 4 and is also bonded to the second sleeve 58 at a position indicated by reference numeral G.

  The flexible shaft 54 is welded to the first sleeve 56. In the present embodiment, the first sleeve 56 and the second sleeve 58 are not bonded and are not fixed in the rotational direction.

  Therefore, in the present embodiment, when the flexible shaft 54 is first rotated by a rotation driving means (not shown), the first sleeve 56 welded to the flexible shaft 54 is rotated. Next, when the first sleeve 56 rotates, the outer jacket 70 bonded thereto rotates. When the outer jacket 70 rotates, the optical fiber FB1 bonded to the outer jacket 70 rotates.

  At this time, the second sleeve 58 bonded to the exterior jacket 70 rotates. As the second sleeve 58 rotates, the optical system housing 64 formed at the tip thereof rotates.

  As described above, in the present embodiment, the optical system housing 64 is not directly rotated by the flexible shaft 54, but the rotational driving force is transmitted to the optical system housing via the optical fiber FB1. Yes.

  In the example shown in FIG. 4, the rotational driving force of the flexible shaft is transmitted to the optical system housing via the optical fiber FB1 without bonding the first sleeve and the second sleeve to each other in the second embodiment. However, the same may be performed in the optical probe 16 of the first embodiment.

  As described above, this embodiment is different from the other embodiments in the drive system of the optical system housing, and is provided with a position restricting means and a friction preventing means in each of the member closing the sheath tip and the housing, The point of holding the position of the housing of the optical system in the sheath and suppressing the occurrence of scratches on the inner surface of the sheath is the same as in the other embodiments.

  Although the optical probe device of the present invention has been described in detail above, the present invention is not limited to the above examples, and various improvements and modifications may be made without departing from the scope of the present invention. Of course.

1 is a block diagram showing a schematic configuration of an optical tomographic imaging apparatus in which an optical probe apparatus according to a first embodiment of the present invention is used. It is a fragmentary sectional view which expands and shows the front-end | tip part of the optical probe of FIG. It is a fragmentary sectional view which expands and shows the front-end | tip part of the optical probe which concerns on 2nd Embodiment of this invention. It is a fragmentary sectional view which expands and shows the front-end | tip part of the optical probe which concerns on 3rd Embodiment of this invention. It is a fragmentary sectional view which expands and shows the front-end | tip part of the conventional optical probe. It is a fragmentary sectional view which expands and similarly shows the front-end | tip part of the conventional optical probe.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Optical tomography apparatus, 12 ... Light source, 14 ... Optical fiber coupler, 16 ... Optical probe, 18 ... Optical rotary adapter, 20 ... Interference light detection part, 22 ... Processing part, 24 ... Display part, 26 ... Optical path length Adjustment unit, 28 ... optical fiber coupler, 30a, 30b ... detection unit, 32 ... operation control unit, 50 ... optical probe, 52 ... sheath (probe outer tube), 54 ... flexible shaft, 56 ... first sleeve, 58 ... first 2 sleeves, 60 ... ferrule, 62 ... hemispherical lens, 64 ... housing, 66 ... projection, 68 ... bush

Claims (11)

An optical probe device that obtains an optical tomographic image using interference light,
A cylindrical sheath that is transparent at least at the tip side and has flexibility;
An output / incident part of the interference light provided in the sheath lumen;
A housing for holding the emission / incident part of the interference light;
A flexible shaft coupled to the housing and transmitting rotation to the housing by a driving means at a rear end;
A member for closing the sheath tip and a position holding means for holding the position of the housing.
The optical probe apparatus, wherein the position holding means also serves as a friction preventing means for preventing friction between an inner surface of a member that closes the sheath tip during rotation of the housing and the housing tip. An optical probe device that obtains an optical tomographic image using interference light,
A cylindrical sheath that is transparent at least at the tip side and has flexibility;
An output / incident part of the interference light provided in the sheath lumen;
A housing for holding the emission / incident part of the interference light;
An optical fiber that guides light and is coupled to the housing and transmits rotation to the housing by a driving means at a rear end;
A flexible shaft indirectly coupled to the housing via an optical fiber;
A member for closing the sheath tip and a position holding means for holding the position of the housing.
The optical probe apparatus, wherein the position holding means also serves as a friction preventing means for preventing friction between an inner surface of a member that closes the sheath tip during rotation of the housing and the housing tip.   The position holding means is formed such that a concave shape formed on a member that closes the sheath distal end and a convex shape formed on the housing distal end are rotatably fitted to each other. Item 3. The optical probe device according to Item 1 or 2.   The position holding means is formed so that a convex shape formed on a member closing the sheath distal end and a concave shape formed on the housing distal end are rotatably fitted to each other. Item 3. The optical probe device according to Item 1 or 2.   The member that closes the sheath tip is formed of a metal member separate from the sheath, and is fixed to the sheath by bonding, screwing, or both bonding and screwing. The optical probe device according to any one of the above.   6. The optical probe device according to claim 5, wherein a concave shape is formed by press-fitting or screwing a resin member into a metal member that forms a member for closing the sheath tip.   The optical probe device according to claim 6, wherein the resin member is a fluororesin or a low wear and high slidable material.   5. The optical probe device according to claim 1, wherein the member for closing the sheath tip and the sheath are formed of separate bodies made of the same material, and are joined together by heat welding. .   9. The optical probe device according to claim 8, wherein a member for closing the sheath tip and the material of the sheath are tetrafluoroethylene perfluoroalkoxyethylene copolymer.   The said position holding means performs position regulation of the said housing front end side direction by contact | abutting the member inner surface and the sheath inner surface which block | close the said housing front end. Optical probe device.   The fitting length between the concave shape formed in the member that closes the sheath tip constituting the position holding means and the convex shape formed at the housing tip is larger than the thrust movement amount of the housing. The optical probe device according to claim 3.

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