JP5221264B2 - Rotary joint and optical tomographic imaging apparatus using the same - Google Patents

Description

  The present invention relates to a rotary joint and an optical tomographic imaging apparatus using the rotary joint, and in particular, guides measurement light to the measurement target and guides return light from the measurement target in order to acquire an optical tomographic image of the measurement target. The present invention relates to a rotary joint that connects optical fibers that rotate freely, and an optical tomographic imaging apparatus that irradiates light to a measurement target and acquires an optical tomographic image of the measurement target from return light due to the reflection.

  As a method for acquiring a cross-sectional image without cutting a measurement target such as a living tissue, there is an optical tomographic imaging apparatus using an optical coherence tomography (OCT) measurement method. This OCT measurement method is a kind of optical interferometry, in which light emitted from a light source is divided into measurement light and reference light, and the optical path length of the measurement light and reference light is within the coherence length of the light source. This is a measurement method using the fact that optical interference is detected only when the ranges match.

  In the optical tomographic imaging apparatus using the OCT measurement method, an optical probe is used. An optical probe irradiates measurement light to a subject to be measured and detects return light due to its reflection, an optical fiber that transmits the measurement light and return light, and a transparent sheath covering them. Composed. This optical probe rotates the measurement unit by rotating the optical fiber and scans the measurement light. For this reason, the base end portion of the optical fiber is rotatably connected to another optical fiber via a rotary joint.

In this way, the rotary joint that connects optical fibers in a rotatable manner requires light to be reliably guided between the rotation side optical fiber (optical probe) and the fixed side optical fiber, and various configurations are proposed. Has been. For example, Patent Document 1 discloses a rotary joint equipped with an optical axis direction adjustment function, and Patent Document 2 proposes a collimating rotary joint. Patent Document 3 proposes a rotary joint in which an optical fiber is optically connected in a non-contact manner through a lens.
US2006 / 0093276A1 US5039193 JP2000-321034

  By the way, since the above-described optical probe is inserted into a patient's body and used, the optical probe is removed from the rotary joint and replaced whenever the patient changes. The optical probe removed from the rotary joint is sterilized and disinfected, and is reconnected to the rotary joint immediately before use. Thus, the optical probe is frequently attached to and detached from the rotary joint.

  When attaching and detaching the optical probe, safety and dust resistance are important. For example, if the laser beam leaks from the optical fiber when the optical probe is removed from the rotary joint, the safety of the user may be impaired. In addition, when dust enters the optical path when the removed optical probe is connected to the rotary joint, there is a problem in that the optical transmission function is deteriorated, the reflection loss is increased, and the optical tomographic image is deteriorated. . For this reason, safety and dustproofness when removing the optical probe are required for the rotary joint.

  However, the rotary joints of Patent Documents 1 to 3 do not consider safety and dustproofness when removing the optical probe (that is, the rotation side optical fiber).

  The present invention has been made in view of such circumstances, and an object thereof is to provide a rotary joint excellent in safety and dustproofness, and an optical tomographic image acquisition apparatus using the rotary joint.

Invention in order to achieve the above object according to claim 1, and a stationary member that supports an end portion of the stationary optical fiber, the rotatably provided on the fixed side member, rotation side of the OCT optical the probe A rotating member that detachably supports the end of the optical fiber and optically connects the rotating side optical fiber and the fixed side optical fiber in a non-contact manner, and an end of the fixed side optical fiber and the rotating side provided on an optical path formed between the end of the optical fiber, the optical path a shutter member for opening and closing the shutter, e Bei and a shutter member provided on said rotary member, said rotary member Is provided with an attachment / detachment portion that is attached / detached by rotating an end portion of the rotation side optical fiber, and the shutter member engages with an end portion of the rotation side optical fiber, and an end portion of the rotation side optical fiber is provided. Rotate in conjunction with There is provided a rotary joint comprising: an engaging portion; and an opening / closing mechanism that opens and closes the shutter when the engaging portion rotates .

According to the present invention, since the shutter member is provided on the optical path, the optical path can be blocked by the shutter member when the end of the rotation side optical fiber is removed. Therefore, light can be prevented from leaking to the outside, and dust can be prevented from entering the optical path.
Further, according to the present invention, when the end portion of the rotation side optical fiber is attached to and detached from the rotation member, the end portion of the rotation side optical fiber is engaged with the engagement portion of the shutter member. And the engaging part of a shutter member rotates with the edge part of a rotation side optical fiber, and a shutter opens and closes. Therefore, since the shutter opens and closes in conjunction with the mounting of the rotation-side optical fiber, it is possible to secure an optical path at the time of mounting, and prevent light leakage and dust adhesion at the time of removal.

According to a second aspect of the present invention, in the first aspect of the invention, the shutter member is characterized in that the shutter is opened by attaching an end of the rotation side optical fiber to the rotation member.

  According to the present invention, the shutter is opened when the end of the rotation side optical fiber is mounted on the rotating member, so that the optical path can be secured at the time of mounting, and optically reliable connection can be achieved.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the shutter member is characterized in that the shutter is closed by removing an end portion of the rotation side optical fiber from the rotation member.

  According to the present invention, the shutter closes when the end portion of the rotation side optical fiber is detached from the rotation member, so that it is possible to prevent light leakage and dust adhesion upon removal.

According to a fourth aspect of the present invention, in any one of the first to third aspects, the shutter member includes a biasing unit that biases the shutter in a closing direction, and rotates an end portion of the rotation-side optical fiber. The shutter is closed by the urging means when detached from the member. According to the present invention, since the shutter is automatically closed by the urging means when the end portion of the rotation side optical fiber is detached from the rotation member, it is possible to reliably prevent light leakage and dust adhesion at the time of removal.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects, a collimating lens is disposed at an end of the fixed side optical fiber and an end of the rotation side optical fiber. . The present invention means a collimating facing rotary joint. In such a collimating facing type, since light leakage prevention and dust prevention are particularly important, the effects of the present invention become remarkable.

According to a sixth aspect of the present invention , in any one of the first to fifth aspects, a cover glass is formed on the optical path formed between the end of the fixed side optical fiber and the end of the rotating side optical fiber. It is provided. According to the present invention, since the cover glass is provided, it is possible to more reliably prevent dust from entering the optical path.

For the described invention to achieve the above objects in claim 7, a light source means for emitting light, a light dividing means which divides the light emitted from the light source unit into measuring light and reference light, the measurement light An OCT optical probe for obtaining the reflected light, a multiplexing means for combining the reflected light and the reference light to obtain interference light, and an interference light detecting means for detecting the interference light And detecting the reflection intensity at a plurality of depth positions of the measurement object based on the detected frequency and intensity of the interference light, and detecting the tomographic image of the measurement object based on the intensity of the reflection light at each depth position. An optical tomographic imaging apparatus comprising: a tomographic image processing means for acquiring a rotary joint according to any one of claims 1 to 6 connected to a proximal end portion of the OCT optical probe. I will provide a.

  According to the present invention, it is possible to prevent light leakage and dust adhesion when the OCT optical probe is detached from the rotary joint. Accordingly, safety can be improved and the accuracy of the optical tomographic image can be improved.

  According to the present invention, the shutter member is provided on the optical path, and the optical path can be blocked by the shutter member when the end of the rotation side optical fiber is removed, so that it is possible to prevent light from leaking to the outside, Dust can be prevented from entering the optical path.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 schematically shows the configuration of an optical tomographic imaging apparatus to which the rotary joint of the present invention is applied.

  An optical tomographic imaging apparatus 10 of the present invention shown in the figure is for acquiring an optical tomographic image of a measurement object by an optical coherence tomography method, and emits light La from a light source unit 12 and light source unit 12. A branching / multiplexing unit 14 that branches the measured light La into the measurement light L1 and the reference light L2, and combines the return light L3 and the reference light L2 from the measurement target that is the subject to generate the interference light L4; The interference light detection unit 20 that detects the interference light L4 generated by the branching / multiplexing unit 14 as an interference signal, and the interference signal detected by the interference light detection unit 20 are processed to obtain an optical tomographic image (hereinafter simply referred to as “tomographic image”). The apparatus main body 11 includes a processing unit 22 that acquires an image) and a display unit 24 that displays an optical tomographic image acquired by the processing unit 22, and is branched by the branching / combining unit 14 of the apparatus main body 11. Guides the measurement light L1 to the measurement target In addition, the optical probe 16 including the rotation-side optical fiber FB1 that guides the return light L3 from the measurement target, and the return light that guides the measurement light L1 to the rotation-side optical fiber FB1 and is guided by the rotation-side optical fiber FB1. A fixed-side optical fiber FB2 that guides L3, and a rotary joint 18 that rotatably connects the rotation-side optical fiber FB1 to the fixed-side optical fiber FB2 and transmits the measurement light L1 and the return light L3.

  Further, the optical tomographic imaging apparatus 10 includes, in the apparatus main body 11, an optical path length adjustment unit 26 that adjusts the optical path length of the reference light L2, an optical fiber coupler 28 that splits the light La emitted from the light source unit 12, and a reference. A detection unit 30a that detects the light L2, a detection unit 30b that detects the return light L3, and an operation control unit 32 that inputs various conditions to the processing unit 22, the display unit 24, and the like, changes settings, and the like. As will be described later, in the optical tomographic imaging apparatus 10 shown in FIG. 1, various light components including the emission light La, the measurement light L1, the reference light L2, the return light L3, and the like described above are configured as constituent elements such as optical devices. Various optical fibers FB (FB3, FB4, FB5, FB6, etc.) including the rotation side optical fiber FB1 and the fixed side optical fiber FB2 are used as light paths for guiding and transmitting between them. Here, the branching / multiplexing unit 14, the interference light detection unit 20, the optical path length adjustment unit 26, the optical fiber coupler 28, and the detection units 30a and 30b constitute an interferometer.

  FIG. 2 is a schematic cross-sectional view of an embodiment of the rotary joint 18. The rotary joint 18 shown in the figure is mainly composed of a fixed member (such as the housing 34 and the fixed sleeve 38), a rotating member (such as the rotating sleeve 46), a motor 36, and a shutter member 56.

  The end portion of the fixed side optical fiber F <b> 2 is fixed to the housing 34 via an attachment member 35. The fixed-side optical fiber FB2 transmits the measurement light L1 branched by the branching / multiplexing unit 14 to the rotation-side optical fiber FB1, and transmits the return light L3 guided by the optical fiber FB1. The ends of the fixed side optical fibers F2 are connected while being held by a cylindrical ferrule (not shown). The ferrule has a function of holding and protecting the optical fiber FB2, and a metal ferrule using a metal such as a zirconia ferrule or a nickel alloy is usually used.

  A fixed-side collimator lens 42 is held via a holder 41 at the end of the fixed-side optical fiber F2. The fixed-side collimator lens 42 collimates the measurement light L1 emitted from the tip of the optical fiber FB2 so as to enter the rotation-side collimator lens 50, and condenses the collimated return light L3 from the rotation-side collimator lens 50. In order to enter the optical fiber FB2. The positional relationship between the end face of the optical fiber FB2 and the collimator lens 42 is such that the distance (on the optical axis) between the center of the end face of the optical fiber FB2 and the center of the collimator lens 42 is equal to the focal length of the collimator lens 42. ing.

  The fixing sleeve 38 is provided in the housing 34 and is fixed to the housing 34. The central axis of the fixed sleeve 38 is arranged coaxially with the center of the fixed collimator lens 42 (that is, the center of the end face of the optical fiber FB2).

  A rotating sleeve 46 is arranged coaxially with the fixed sleeve 38 inside the fixed sleeve 38. The rotating sleeve 46 is rotatably supported by the fixed sleeve 38 via a bearing 44.

  A cover lens 37 is attached to the inside of the rotation sleeve 46 so that the above-described fixed-side collimator lens 42 is not exposed to the outside.

  A gear 52 is attached to the outer peripheral surface of the rotating sleeve 46, and the gear 52 is meshed with a gear 54 connected to the output shaft 36 a of the motor 36. Accordingly, the rotation sleeve 46 is rotated via the gear 54 and the gear 52 by driving the motor 36. 2 illustrates an example in which the motor 36 is fixed to the outside of the housing 34, the motor 36 may be disposed inside the housing 34.

  The rotation sleeve 46 is provided with an attachment / detachment portion 46A to / from which the rotation side optical fiber FB1 is attached / detached. The detachable portion 46A is formed at the end opposite to the side on which the fixed side optical fiber FB2 is fixed.

  The rotation-side optical fiber FB1 guides the measurement light L1 transmitted from the fixed-side optical fiber FB2 to the measurement target and guides the return light L3 from the measurement target to transmit it to the fixed-side optical fiber FB2. It is.

  The end of the rotation side optical fiber FB1 is held by a cylindrical ferrule (not shown), and a connecting member 53 is attached to the outside thereof. The ferrule has a function of holding and protecting the optical fiber FB1, and a metal ferrule using a metal such as a zirconia ferrule or a nickel alloy can be usually used. The connecting member 53 is configured to be detachably connected to the attaching / detaching portion 46 </ b> A of the rotating sleeve 46. For example, the female screw 46B is formed on the inner peripheral surface of the rotating sleeve 46, and the male screw 53B is formed on the outer peripheral surface of the connecting member 53 so as to be screwed into the female screw 46B. Accordingly, the connecting member 53 can be attached to the rotating sleeve 46 by rotating the connecting member 53 to the rotating sleeve 46. In addition, the connection mechanism of the connection member 53 (rotation side optical fiber FB1) and the rotation sleeve 46 is not limited to this, A various aspect is possible.

  A rotation-side collimator lens 50 is attached via a holder 51 to the end of the rotation-side optical fiber FB2. The rotation-side collimator lens 50 condenses the collimated measurement light L1 from the collimator lens 42 and causes it to enter the optical fiber FB1, and collimates the return light L3 emitted from the tip of the optical fiber FB1, thereby fixing the fixed-side collimator. This is for entering the lens 42. The positional relationship between the front end surface of the optical fiber FB1 and the collimator lens 50 is such that the distance (on the optical axis) between the center of the end surface of the optical fiber FB1 and the center of the collimator lens 50 is equal to the focal length of the collimator lens 50. ing.

  A cover glass 39 is provided inside the connecting member 53 so that the collimator lens 50 is not exposed to the outside.

  Incidentally, the rotary joint 18 of the present invention is provided with a shutter member 56. 3 (a) and 3 (b) are front views showing the configuration of the shutter member 56, FIG. 3 (a) shows a state in which the shutter 57 is closed, and FIG. 3 (b) shows that the shutter 57 is opened. Shows the state.

  The shutter member 56 shown in these drawings uses an iris diaphragm mechanism and includes a plurality of shutters 57. The shutter 57 is interlocked with the rotation operation of the dock 58, and is opened according to the position of the dock 58, or the opening is made small and completely closed. For example, when the dock 58 is disposed at the position shown in FIG. 3A, the shutter 57 is closed and completely closed. When the dock 58 is disposed at the position shown in FIG. 3B, the shutter 47 is opened to secure an optical path. The dock 58 acts as an engaging portion that engages with the shaft 59 of the connecting member 53.

  FIG. 4 is a front view showing an end face of the connecting member 53. As shown in the figure, the connecting member 53 has two shafts 59 protruding therefrom. The distance between the shafts 59 and 59 is larger than the diameter of the dock 58, and the dock 58 can be disposed between the shafts 59 and 59. Therefore, the shafts 59 can be arranged on both sides of the dock 58 as shown by the two-dot chain line in FIG. 3A or 3B. Thus, since the dock 58 is engaged with the shaft 59, when the end portion (that is, the connecting member 53) of the rotation side optical fiber FB1 is rotated with respect to the rotation sleeve 46, the dock 58 is rotated and the shutter 57 is rotated. Can be opened and closed.

  The shutter member 56 opens the shutter 57 when the connecting member 53 is attached to the rotating sleeve 46, and closes the shutter 57 when the connecting member 53 is removed from the rotating sleeve 46.

  In this embodiment, the shutter member 56 using the iris diaphragm mechanism is used. However, any configuration that opens and closes the opening on the optical path may be used.

  Next, each component which comprises the optical tomographic imaging apparatus 10 of FIG. 1 to which the rotary joint 18 of this invention is applied is demonstrated.

  As shown in FIG. 1, the light source unit 12 includes a semiconductor optical amplifier 60, an optical splitter 62, a collimator lens 64, a diffraction grating element 66, an optical system 67, and a rotary polygon mirror 68, and has a frequency. Is emitted at a constant cycle.

  The semiconductor optical amplifier (semiconductor gain medium) 60 emits weak emission light and amplifies incident light when a drive current is applied. An optical fiber FB10 is connected to the semiconductor optical amplifier 60. Specifically, one end of the optical fiber FB10 is connected to a portion where light is emitted from the semiconductor optical amplifier 60, and the other end of the optical fiber FB10 is connected to a portion where light enters the semiconductor optical amplifier 60. Therefore, the light emitted from the semiconductor optical amplifier 60 is emitted to the optical fiber FB10 and enters the semiconductor optical amplifier 60 again.

  Thus, by forming a loop of the optical path with the semiconductor optical amplifier 60 and the optical fiber FB10, the semiconductor optical amplifier 60 and the optical fiber FB10 become an optical resonator, and a driving current is applied to the semiconductor optical amplifier 60. Pulsed laser light is generated.

  An optical branching device 62 is provided on the optical path of the optical fiber FB10. An optical fiber FB11 is connected to the optical branching device 62, and a part of the light guided in the optical fiber FB10 is branched to the optical fiber FB11.

  The collimator lens 64 is disposed at the other end of the optical fiber FB11, that is, the end not connected to the optical fiber FB10, and makes the light emitted from the optical fiber FB11 parallel light.

  The diffraction grating element 66 is disposed at a predetermined angle on the optical path of the parallel light generated by the collimator lens 64. The parallel light emitted from the collimator lens 64 is split by the diffraction grating element 66. An optical system 67 is disposed on the optical path of the split light. The optical system 67 is composed of a plurality of lenses, refracts the light split by the diffraction grating element 66, and converts the refracted light into parallel light.

  A rotating polygon mirror 68 is disposed on the optical path of the parallel light, and the parallel light is reflected by the rotating polygon mirror 68. The rotating polygon mirror 68 is a regular octagonal rotating body that rotates at a constant speed in the direction R1 in FIG. 1, and its center is a rotating shaft. Therefore, the angle of each reflecting surface can be changed with respect to the optical axis of the optical system 67 by rotating the rotary polygon mirror 68. The light reflected by the rotary polygon mirror 68 passes through the optical system 67, the diffraction grating element 66, and the collimator lens 64 and enters the optical fiber FB11.

  Here, as described above, since the angle of both reflections of the rotating polygon mirror 68 changes with respect to the optical axis of the optical system 67, the angle at which the rotating polygon mirror 68 reflects light changes with time. For this reason, only the light in a specific frequency region out of the light dispersed by the diffraction grating element 66 enters the optical fiber FB11 again. Here, the light in a specific frequency range incident on the optical fiber FB11 is determined by the angle between the optical axis of the optical system 67 and the reflecting surface of the rotary polygon mirror 68. Therefore, the frequency range of the light incident on the optical fiber FB11 is It changes depending on the angle between the optical axis of the optical system 67 and the reflecting surface of the rotary polygon mirror 68.

  The light in a specific frequency range that has entered the optical fiber FB11 is incident on the optical fiber FB10 from the optical splitter 62, and is combined with the light in the optical fiber FB10. Thus, the pulsed laser light guided to the optical fiber FB10 becomes laser light in a specific frequency range, and the laser light La in the specific frequency range is emitted to the optical fiber FB3. Here, since the rotating polygon mirror 68 rotates at a constant speed in the direction of the arrow Rl, the wavelength λ of the light incident on the optical fiber FB11 again changes with a constant period as time passes. As a result, the frequency of the laser light La emitted to the optical fiber FB3 also changes at a constant period with the passage of time. The light source unit 12 has such a configuration, and emits the wavelength-swept laser light La toward the optical fiber FB3.

  Next, the branching / combining unit 14 is configured by, for example, a 2 × 2 optical fiber coupler, and is optically connected to the optical fiber FB2, the optical fiber FB3, the optical fiber FB4, and the optical fiber FB5, respectively. The branching / combining unit 14 divides the light La incident from the light source unit 12 through the optical fiber FB3 into the measurement light L1 and the reference light L2, causes the measurement light L1 to enter the optical fiber FB2, and the reference light L2 The light enters the fiber FB5. Further, the branching / combining unit 14 is incident on the optical fiber FB5, and after returning to the optical fiber FB5 after being subjected to frequency shift and optical path length change by the optical path length adjusting unit 26 described later, is incident on the branching / combining unit 14 The reference light L2 and the return light L3 from the measuring object S, which is acquired by the optical probe 16 described later and is incident on the branching / combining unit 14 from the optical fiber FB2, are combined and emitted to the optical fiber FB4.

  The optical probe 16 is connected to the optical fiber FB2 via the rotary joint 18. The measurement light L1 is incident on the optical fiber FB1 from the optical fiber FB2 via the rotary joint 18, and the incident measurement light L1 is incident. Is transmitted by the optical fiber FB1 to irradiate the measurement target S, the return light L3 from the measurement target S is acquired, the acquired return light L3 is transmitted by the optical fiber FB1, and the optical fiber is transmitted via the rotary joint 18. The light is emitted to FB2.

  As shown in FIG. 5, the optical probe 16 includes a probe outer cylinder 70, a cap 72, an optical fiber FB <b> 1, a spring 74, a fixing member 76, and an optical lens 78.

  The probe outer cylinder (sheath) 70 is a cylindrical member having flexibility, and is made of a material through which the measurement light L1 and the return light L3 are transmitted. The probe outer cylinder 70 has a part around the tip (the tip of the optical fiber FB1 opposite to the rotary joint 18, hereinafter referred to as the tip of the probe outer cylinder 70) through which the measurement light L1 and the return light L3 pass. What is necessary is just to be formed with the material (transparent material) which permeate | transmits light. The cap 72 is provided at the tip of the probe outer cylinder 70 and closes the tip of the probe outer cylinder 70.

  The optical fiber FB1 is a linear member and is accommodated in the probe outer tube 70 along the probe outer tube 70, and guides the measurement light L1 emitted from the optical fiber FB2 through the rotary joint 18 to the optical lens 78. At the same time, the measurement light L1 is irradiated to the measurement object S, and the return light L3 from the measurement object S acquired by the optical lens 78 is guided to the rotary joint 18 and enters the optical fiber FB2. Here, the optical fiber FB1 and the optical fiber FB2 are connected by the rotary joint 18, and are optically connected in a state where the rotation of the optical fiber FB1 is not transmitted to the optical fiber FB2. The optical fiber FB1 is disposed so as to be rotatable with respect to the probe outer tube 70.

  The spring 74 is fixed to the outer periphery of the optical fiber FB1. The optical fiber FB1 and the spring 74 are connected to the rotary joint 18.

  The optical lens 78 is disposed at the measurement-side tip of the optical fiber FB1 (tip of the optical fiber FB1 opposite to the rotary joint 18), and the tip part measures the measurement light L1 emitted from the optical fiber FB1. In order to collect the light, it is formed in a substantially spherical shape.

  The optical lens 78 irradiates the measurement object S with the measurement light L1 emitted from the optical fiber FB1, collects the return light L3 from the measurement object S, and enters the optical fiber FB1.

  The fixing member 76 is disposed on the outer periphery of the connection portion between the optical fiber FB1 and the optical lens 78, and fixes the optical lens 78 to the end portion of the optical fiber FB1. Here, the fixing method of the optical fiber FB1 and the optical lens 78 by the fixing member 76 is not particularly limited. Even if the fixing member 76, the optical fiber FB1 and the optical lens 78 are bonded and fixed by an adhesive, a bolt or the like is used. May be fixed with a mechanical structure. The fixing member 76 may be any member as long as it is used for fixing, holding or protecting the optical fiber such as a zirconia ferrule or a metal ferrule.

  As described above, the optical fiber FB1 and the spring 74 are connected to the rotary sleeve 46 of the rotary joint 18. By rotating the optical fiber FB1 and the spring 74 by the rotary sleeve 46, the optical lens 78 is removed from the probe. The tube 71 is rotated in the direction of arrow R2. The rotary joint 18 includes a rotary encoder (not shown), and detects the irradiation position of the measurement light L1 from position information (angle information) of the optical lens 78 based on a signal from the rotary encoder. That is, the angle with respect to the reference position in the rotation direction of the rotating optical lens 78 is detected to detect the measurement position.

  The optical probe 16 is configured as described above, and the measurement light L1 emitted from the optical lens 78 is measured by rotating the optical fiber FB1 and the spring 74 in the direction of arrow R2 in FIG. The object S is irradiated while scanning in the direction of the arrow R2 (circumferential direction of the probe outer cylinder 70), and the return light L3 is acquired. Thereby, the return light L3 reflected from the measuring object S can be acquired on the entire circumference of the probe outer cylinder 70 in the circumferential direction.

  The optical path length adjustment unit 26 in FIG. 1 is disposed on the output side of the reference light L2 of the optical fiber FB5 (that is, the end of the optical fiber FB5 opposite to the branching / combining unit 14). The optical path length adjustment unit 26 includes a first optical lens 80 that converts the light emitted from the optical fiber FB5 into parallel light, a second optical lens 82 that condenses the light converted into parallel light by the first optical lens 80, and The reflection mirror 84 that reflects the light collected by the second optical lens 82, the base 86 that supports the second optical lens 82 and the reflection mirror 84, and the base 86 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 80 and the second optical lens 82.

  The first optical lens 80 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 84 on the core of the optical fiber FB5. The second optical lens 82 condenses the reference light L2 converted into parallel light by the first optical lens 80 on the reflection mirror 84 and makes the reference light L2 reflected by the reflection mirror 84 parallel light. Thus, the first optical lens 80 and the second optical lens 82 form a confocal optical system.

  Further, the reflection mirror 84 is disposed at the focal point of the light collected by the second optical lens 82 and reflects the reference light L2 collected by the second optical lens 82. As a result, the reference light L2 emitted from the optical fiber FB5 becomes parallel light by the first optical lens 80 and is condensed on the reflection mirror 84 by the second optical lens 82. Thereafter, the reference light L2 reflected by the reflection mirror 84 is converted into parallel light by the second optical lens 82, and is condensed on the core of the optical fiber FP5 by the first optical lens 80.

  The base 86 fixes the second optical lens 82 and the reflection mirror 84, and the mirror moving mechanism 88 moves the base 86 in the optical axis direction of the first optical lens 80 (direction of arrow A in FIG. 1). . By moving the base 86 in the direction of arrow A with the mirror moving mechanism 88, the distance between the first optical lens 80 and the second optical lens 82 can be changed, and the optical path length of the reference light L2 can be adjusted. Can do.

  The interference light detection unit 20 is connected to the optical fiber FB4, and detects the interference light L4 generated by combining the reference light L2 and the return light L3 by the branching / combining unit 14 as an interference signal. Here, the optical tomographic imaging apparatus 10 is provided in the optical fiber coupler 28 that branches the laser light La from the optical fiber FB3 to the optical fiber FB6, and the optical fiber FB6 that branches from the optical fiber coupler 28, and the branched laser. The detection unit 30a detects the light intensity of the light La, and the detection unit 30b detects the light intensity of the interference light L4 on the optical path of the optical fiber FB4. The interference light detection unit 20 adjusts the balance of the light intensity of the interference light L4 detected from the optical fiber FB4 based on the detection results of the detection unit 30a and the detection unit 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, the surface of the probe outer cylinder 70 of the optical probe 16. A region that can be considered to be in contact with the surface of the measuring object S is detected, and a tomographic image is acquired from the interference signal detected by the interference light detection unit 20.

  As illustrated in FIG. 6, the processing unit 22 includes an interference signal acquisition unit 90, an A / D conversion unit 92, a contact area detection unit 94, a tomographic information generation unit 96, and an image quality correction unit 98.

  The interference signal acquisition unit 90 acquires the interference signal detected by the interference light detection unit 20, and further, information on the measurement position detected by the rotary joint 18, specifically, position information of the optical lens 78 in the rotation direction. The position information of the measurement position detected from is acquired, and the interference signal is associated with the position information of the measurement position. The associated interference signal is sent to the A / D conversion unit 92. The A / D converter 92 converts the interference signal output as an analog signal into a digital signal. The digitally converted interference signal is sent to the contact area detector 94 and the tomographic information generator 96.

  The contact area detection unit 94 applies an FFT (Fast Fourier Transform) to the interference signal converted into the digital signal to obtain the relationship between the frequency component and the intensity of the interference signal, and the detected frequency component and the relationship between the frequency component and the intensity. By associating the depth direction (the direction away from the rotation center), information on the relationship between the depth direction and the strength is acquired. The contact area detection unit 94 measures the position of the surface of the probe outer cylinder 70 at the position where the measurement light L1 is transmitted and the probe outer cylinder 70 at the position where the measurement light L1 is transmitted and the measurement from the information on the relationship between the depth direction and the intensity. A contact area with the object S is detected.

  The contact area between the probe outer cylinder 70 and the measuring object S detected by the contact area detection unit 94 in this way is sent to the tomographic information generation unit 96. The tomographic information generation unit 96 acquires a tomographic image in the depth direction by processing information on the relationship between the frequency component and the intensity. Here, the tomographic information generation unit 96 acquires a tomographic image of only the interference signal of the position information determined as the contact region from the contact region information sent from the contact region detection unit 94, and acquires the position information other than the contact region. The interference signal does not acquire a tomographic image, that is, performs mask processing without performing image acquisition processing from the result of applying FFT or FFT.

  Next, image generation in the tomographic information generation unit 96 will be briefly described. When the measurement light L1 is irradiated onto the measurement object S, interference fringes with respect to each optical path length difference 1 when the return light L3 from each depth of the measurement object S and the reference light L2 interfere with each other with various optical path length differences. S (l) is the light intensity I (k) of the interference signal detected by the interference light detector 20.

で表される。ここでｋは波数、ｌは光路長差である。上式は波数ｋ＝ω／ｃを変数とする光周波数領域のインターフェログラムとして与えられていると考えることができる。このため、断層情報生成部９６において、干渉光検出部２０で検出したスペクトル干渉縞に高速フーリエ変換を施し、干渉光Ｌ４の光強度Ｓ（１）を決定することにより、測定対象Ｓの測定開始位置からの距離情報と反射強度情報とを取得し、断層画像を生成することができる。

It is represented by Here, k is the wave number, and l is the optical path length difference. It can be considered that the above equation is given as an interferogram in the optical frequency domain with the wave number k = ω / c as a variable. For this reason, the tomographic information generation unit 96 performs fast Fourier transform on the spectral interference fringes detected by the interference light detection unit 20, and determines the light intensity S (1) of the interference light L4, thereby starting measurement of the measurement target S. The distance information from the position and the reflection intensity information can be acquired and a tomographic image can be generated.

  The image quality correction unit 98 performs logarithmic conversion and radial conversion on the tomographic image generated by the tomographic information generation unit 96 to obtain a circular image centered on the rotation center of the optical lens 78. Furthermore, the image quality correction unit 98 corrects the image quality by performing sharpening processing, smoothing processing, and the like on the tomographic image. The image quality correction unit 98 transmits the tomographic image subjected to the image quality correction to the display unit 24. Here, the transmission timing of the tomographic image is not particularly limited, and may be transmitted to the display unit 24 every time processing of one line is finished, and may be rewritten and displayed for each line. May be transmitted at the stage when the processing of the image acquired by making one round is completed and one circular tomographic image is formed.

  The display unit 24 in FIG. 1 is a CRT, a liquid crystal display device, or the like, and displays the tomographic image transmitted from the image quality correction unit 98. 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 the above-described saddle value and various processing conditions of the processing unit 22 based on an operator instruction input from the input unit, changes the display setting of the display unit 24, and the like. I do. 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. Further, the operation control unit 32 may perform operation control of the light source unit 12, the rotary joint 18, the interference light detection unit 20, the optical path length adjustment unit 26, and the detection units 30a and 30b, and setting various conditions.

  Next, in the optical tomographic imaging apparatus 10 configured as described above, an interference light and interference signal acquisition method for measuring the measurement object S will be described.

  First, the optical path length is adjusted and set so that the measuring object S is positioned in the measurable region by moving the base 86 in the arrow A direction by the mirror moving mechanism 88. Thereafter, the laser light La is emitted from the light source unit 12. The emitted laser light La is split into measurement light L1 and reference light L2 by the branching / combining unit 14. The measurement light L1 is guided through the optical fiber FB2, the rotary joint 18 of the present invention, and the optical probe 16 (optical fiber FB1), and is irradiated onto the measurement object S.

  At this time, the optical fiber FB1 and the optical lens 78 in the optical probe 16 are rotated by the rotary joint 18 of the present invention. That is, the motor 36 of the rotary joint 18 is driven, the rotary shaft 36a rotates, the gear 54 attached to the tip of the rotary shaft 18a rotates, and the gear 52 screwed with the gear 54 rotates. The rotation of the gear 52 causes the optical fiber FB1 to rotate through the rotation of the rotating sleeve 46. As a result, the optical fiber FB1 in the optical probe 16 also rotates, and the optical lens 78 attached to the tip of the optical fiber FB1 also rotates.

  On the other hand, the measurement light L1 transmitted through the optical fiber FB2 held by the fixed sleeve 38 and emitted from the end face of the optical fiber FB2 enters the collimator lens 42 held by the fixed sleeve 38 and is collimated. Then, the light is incident on the collimator lens 50 held by the connecting member 53 that rotates together with the rotating sleeve 46, and after being collected, enters the optical fiber FB1, and is optically transmitted into the optical fiber FB1 in the optical probe 16, The light enters the optical lens 78, passes through the probe outer cylinder 70 from the optical lens 78, and irradiates the measuring object S.

  At this time, since the optical fiber FB1 and the optical lens 78 in the optical probe 16 are rotated by the rotary joint 18, the measurement light L1 is irradiated over the entire circumference of the measurement target S such as a body cavity. At this time, the rotary joint 18 detects information on the measurement position of the measurement symmetry S by a rotary encoder (not shown) or the like. Then, the light reflected at each depth position of the measuring object S enters the optical probe 16 as the return light L3. Also at this time, since the optical fiber FB1 and the optical lens 78 in the optical probe 16 are rotated by the rotary joint 18, the return light L3 from the entire circumference of the measuring object S is incident on the rotating optical lens 78. become. The return light L3 is incident on the branching / combining unit 14 via the optical probe 16 (optical fiber FB1), the rotary joint 18, and the optical fiber FB2.

  At that time, the return light L3 emitted from the end face of the optical fiber FB1 is incident on the collimator lens 50 held by the rotating sleeve 46 that is rotating, collimated, and then held by the stationary sleeve 38 that is stationary. The light enters the collimator lens 42 and is condensed. Then, the light enters the end face of the optical fiber FB 2, is optically transmitted by the optical fiber FB 2, and enters the branching / combining unit 14.

  On the other hand, the reference light L2 is incident on the optical path length adjustment unit 26 through the optical fiber FB5. Then, the reference light L <b> 2 whose optical path length is adjusted by the optical path length adjusting unit 26 is guided again through the optical fiber FB <b> 5 and enters the branching / multiplexing unit 14. Then, the branching / multiplexing unit 14 combines the return light L3 from the measurement target S with the reference light L2 whose optical path length is adjusted by the optical path length adjusting unit 40. Thereby, the interference light L4 between the return light L3 and the reference light L2 is generated. The generated interference light is detected as an interference signal by the interference light detection unit 20.

  The interference signal detected by the interference light detection unit 20 is sent to the processing unit 22. In the processing unit 22, the interference signal acquisition unit 90 acquires the interference signal, acquires information on the measurement position detected by the rotary joint 18, and associates the interference signal with the position information on the measurement position. The associated interference signal is converted into a digital signal by the A / D converter 92 and sent to the contact area detector 94 and the tomographic information generator 96. The contact area detection unit 94 detects a contact area between the probe outer cylinder 70 and the measurement target S, and information on the detected contact area between the probe outer cylinder 70 and the measurement target S is sent to the tomographic information generation unit 96. . In the tomographic information generation unit 96, information on the relationship between the frequency component and the intensity acquired by subjecting the interference signal converted into the digital signal to FFT is determined as the contact region from the contact region information sent from the contact region detection unit 94. By processing only the interference signal of the positional information, a tomographic image in the depth direction for the contact area is acquired. The tomographic image acquired by the tomographic information generation unit 96 is sent to the image quality correction unit 98. The image quality correction unit 98 performs logarithmic conversion and radial conversion on the tomographic image generated by the tomographic information generation unit 96 to obtain a circular tomographic image centered on the rotation center of the optical lens 78 and sharpening. Processing, smoothing processing, and the like are performed, and the image quality is corrected. The tomographic image subjected to the image quality correction by the image quality correction unit 98 is transmitted to the display unit 24. The display unit 24 displays the tomographic image after image quality correction transmitted from the image quality correction unit 98.

  Next, the operation of the rotary joint 18 of the present invention will be described.

  The rotary joint 18 is provided with a shutter member 56. When the optical probe 16 (that is, the rotation-side optical fiber FB1) is removed, the shutter 57 of the shutter member 56 is interlocked, as shown in FIG. The opening is completely closed. Therefore, the measurement light L1 can be prevented from leaking, and safety can be improved. Moreover, since the opening is completely closed, it is possible to prevent dust from entering the optical path. Accordingly, it is possible to prevent the optical tomographic image from being deteriorated due to a decrease in the light transmission function or an increase in reflection loss, as in the case where dust enters the optical path.

  Further, when the probe 16 is connected to the rotary joint 18, the shutter 57 of the shutter member 56 is interlocked to form an opening as shown in FIG. Thereby, since an optical path can be ensured, the measurement light L1 and the return light L3 can be reliably transmitted.

  As described above, according to the present embodiment, the shutter member 56 is provided on the optical path, and the optical path can be blocked by the shutter member 56 when the end of the rotation side optical fiber FB1 is removed. Can be prevented, and dust can be prevented from entering the optical path.

  In the above-described embodiment, the dog 58 of the shutter member 56 is engaged with the shaft 59 of the connecting member 53, but the configuration and mechanism to be engaged are not limited to this.

  Further, the shutter 57 of the shutter member 56 may be biased in the closing direction. For example, in the connecting member 53 shown in FIG. 4, the shaft 59 is single and a spring spring (not shown) is provided inside the shutter member 56 of FIG. 3 to bias the shutter 57 in the closing direction. Thereby, when the connecting member 53 (rotation side optical fiber FB1) is removed from the rotary joint 18, the shutter 57 is automatically closed.

  In the above-described embodiment, the shutter member 56 using the iris diaphragm mechanism is used. However, any configuration may be used as long as the opening on the optical path is opened and closed. For example, a guillotine type shutter mechanism may be used.

  Further, as shown in FIG. 7A, a shutter member may be provided by providing a light shielding plate 61 in a rotatable manner in the rotating sleeve 46. In this case, it is preferable that the light shielding plate 61 swings to the side opposite to the side where the connecting member 53 (rotation side fiber FB1) is connected. Thereby, the light shielding plate 61 can be automatically retracted from the optical path by pushing the connecting member 53. The light shielding plate 61 may be returned to its original closed position by its own weight or a biasing means such as a spring. Thereby, by removing the connecting member 53, the light shielding plate 61 can be automatically placed on the optical path and closed.

  Further, the shutter member may have a structure in which the light shielding plate 61 is slid as shown in FIG.

  In the optical tomographic imaging apparatus 10 shown in FIG. 1 described above, the integrated branching and multiplexing unit 14 branches the light La emitted from the light source unit 12 into the measurement light L1 and the reference light L2, and Although the interference light L4 is generated by combining the return light L3 and the reference light L2 from the measurement target that is the subject, the present invention is not limited to this, and the branching unit and the combining unit are provided separately, The branching unit may branch the emission light La to the measurement light L1 and the reference light L2, and combine the return light L3 from the measurement target with the reference light L2 and generate the interference light L4.

  FIG. 8 is a schematic sectional view of an optical tomographic imaging apparatus according to another embodiment. The optical tomographic imaging apparatus 10a shown in the figure can apply the rotary joint 18 according to the present invention, similarly to the optical tomographic imaging apparatus 10 shown in FIG.

  The optical tomographic imaging apparatus 10a shown in FIG. 8 is provided with a branching / combining unit 14 and an optical fiber coupler 28 in the apparatus main body 11 of FIG. 1 as compared with the optical tomographic imaging apparatus 10 shown in FIG. On the other hand, the apparatus main body 11a of FIG. 8 is different in that a branching section 14a, a multiplexing section 14b, optical circulators 25a and 25b, and polarization controllers 27a and 27b are provided. In addition, what has the same structure attaches | subjects the same number and abbreviate | omits the description.

  An optical tomographic imaging apparatus 10a shown in FIG. 1 includes a light source unit 12, a branching unit 14a that branches light La emitted from the light source unit 12 into measurement light L1 and reference light L2, and a measurement object that is a subject. A combining unit 14b that combines the return light L3 and the reference light L2a to generate interference light L4a and L4b, and an interference light detection that detects an interference signal based on the interference light L4a and L4b generated by the combining unit 14b. Unit 20, a processing unit 22 that processes an interference signal to obtain an optical tomographic image, and a display unit 24 that displays the optical tomographic image, and a measurement branched by a branching unit 14a of the device main body 11a While guiding the light L1 to the measurement target and guiding the return light L3 from the measurement target, the optical probe 16 includes the rotation-side optical fiber FR1, and the measurement light L1 is guided to the rotation-side optical fiber FB1. The fixed side optical fiber FB2 that guides the return light L3 guided by the rotation side optical fiber FB1 and the rotation side optical fiber FB1 are rotatably connected to the fixed side optical fiber FB2, and the measurement light L1 and the return light are connected. And a rotary joint 18 that transmits L3.

  The optical tomographic imaging apparatus 10a further includes an optical path length adjustment unit 26 that adjusts the optical path length of the reference light L2, a polarization controller 27a that rotates the polarization direction of the reference light L2, and return light. The polarization controller 27b that rotates the polarization direction of L3 and the reference light L2 guided from the branching portion 14a are guided to the optical path length adjusting unit 26, and the optical path length adjusted that can be introduced from the optical path length adjusting unit 26 A circulator 25a that guides the reference light L2a to the polarization controller 27a, a measurement light L1 that is guided from the branching portion 14a, is guided to the rotary joint 18, and a return light L3 that is guided from the rotary joint 18 is polarized. A circulator 25b guided to the wave controller 27b, a first detector 30a for detecting the first interference light L4a generated by the multiplexer 14b, and a multiplexer 14b. A second detector 30b for detecting the generated second interference light L4b, input of various conditions in the processor 22, the display unit 24 or the like, and an operation control unit 32 for changing the settings and the like.

  Here, the branching unit 14a, the combining unit 14b, the interference light detecting unit 20, the circulators 25a and 25b, the optical path length adjusting unit 26, the polarization controllers 27a and 27b, the detecting units 30a and 30b, and the above-described optical fiber FB ( FB1 to FB8) constitute an interferometer.

  For example, the branching portion 14a is configured by a 2 × 2 optical fiber coupler, and is optically connected to the optical fibers FB3, FB2a, and FB5a, respectively.

  The branching unit 14a divides the light La incident from the light source unit 12 through the optical fiber FB3 into the measurement light L1 and the reference light L2, and causes the measurement light L1 to enter the optical circulator 25b through the optical fiber FB2a. The light L2 is incident on the optical circulator 25a through the optical fiber FB5a.

  The multiplexing unit 14b is configured by, for example, a 2 × 2 optical fiber coupler, and is optically connected to the optical fibers FB4a, FB4b, FB7, and FB8, respectively. The multiplexing unit 14b combines the reference light L2a incident from the polarization controller 27a via the optical fiber FB7 and the return light L3 incident from the polarization controller 27b via the optical fiber FB8 to combine the first interference light. L4a and second interference light L4b are generated, the first interference light L4a is incident on the first detection unit 30a via the optical fiber FB4a, and the second interference light L4b is input to the second detection unit 30b via the optical fiber FB4b. Make it incident.

  The optical circulator 25a is connected to the optical fibers FB5, FB5a, and FB7, and transmits light guided from the predetermined optical fiber to the predetermined optical fiber. Specifically, the optical circulator 25a transmits the reference light L2 guided from the branching portion 14a via the optical fiber FB5a to the optical fiber FB5, and guides it to the optical path length adjustment unit 26, and also optical path length adjustment unit. The optical path length is adjusted at 26, reflected, and the reference light L2a guided through the optical fiber FB5 is transmitted to the optical fiber FB7 and guided to the polarization controller 27a.

  The optical circulator 25b is connected to the optical fibers FB2, FB2a, and FB8, and transmits light guided from the predetermined optical fiber to the predetermined optical fiber. Specifically, the optical circulator 25b transmits the measurement light L1 guided from the branch part 14a through the optical fiber FB2a to the optical fiber FB2 and guides it to the rotary joint 18, and from the rotary joint 18 to the optical fiber. The return light L3 guided through FB2 is transmitted to the optical fiber 8 and guided to the polarization controller 27b.

  The polarization controller 27a is optically connected to the optical fiber FB7 and rotates the polarization direction of the reference light L2a. The polarization controller 27b is optically connected to the optical fiber FB8 and rotates the polarization direction of the return light L3. Here, as the polarization controllers 27a and 27b, for example, a known technique such as JP-A-2001-264246 can be used.

  The polarization directions of the return light L3 and the reference light L2a are adjusted by the polarization controllers 27a and 27b so that the polarization directions of the return light L3 and the reference light L2a are matched. Since the return light L3 and the reference light L2a adjusted so as to be combined, the tomographic image can be made clearer. Here, it is preferable that the polarization controllers 27a and 27b can be operated by a doctor or the like through the operation unit.

  The interference light detection unit 20 is connected to the detection units 30a and 30b via the optical fibers FB4a and FB4b, respectively, and the first interference light L4a that has passed through the first detection unit 30a and the second detection unit 30b that has passed through the second detection unit 30b. The interference signal is detected (or generated) from the difference from the two interference lights L4b. Specifically, the interference light detection unit 20 includes a detection unit such as a photodiode that photoelectrically converts and detects interference light, and a difference amplifier that detects a difference from the value detected by the detection unit. The first interference light L4a and the second interference light L4b are photoelectrically converted, the detected value is input to the difference amplifier 73, and the difference is amplified by the difference amplifier 73 to generate an interference signal.

  Thus, by detecting the balance between the two interference lights, the first interference light L4a and the second interference light L4b, in-phase optical noise other than the interference signal can be removed while amplifying and outputting the interference signal, The image quality of the tomographic image can be improved.

  Moreover, the interference light detection unit 20 adjusts the balance of the light intensities of the first interference light L4a and the second interference light L4b to be detected based on the detection results of the detector 30a and the detection unit 30b. In this way, the balance of the light intensity between the first interference light L4a and the second interference light L4b is adjusted based on the detection results of the detection unit 30a and the detection unit 30b. Specifically, the intensity is set to 50:50. Thus, the white noise component can be reduced and the S / N ratio can be increased.

  As described above, the optical tomographic imaging apparatus 10a shown in FIG. 8 can acquire the optical tomographic image of the measurement target with high resolution efficiently as in the optical tomographic imaging apparatus 10 shown in FIG. it can.

  Further, the optical tomographic imaging apparatuses 10 and 10a described above detect a contact area with a measurement target and acquire a tomographic image of the measurement target by using an SS-OCT (swept source-OCT) measurement method. The invention is not limited to this, and other OCT measurement methods may be applied. Examples of other applicable OCT measurement methods include an SD-OCT (spectral domain-OCT) measurement method and a TD-OCT (time domain-OCT) measurement method.

  As described above, the rotary joint according to the present invention and the optical tomographic imaging apparatus using the rotary joint have been described in detail with various embodiments. However, the present invention is not limited to the above embodiments, and the present invention is not limited thereto. Various improvements and changes may be made without departing from the scope of the invention.

  For example, in the above-described embodiment, the fixed sleeve 38 and the rotary sleeve 46 of the rotary joint 18 are integrally formed, but the rotary side optical transmission system including the rotary side optical fiber FB1 and the rotary side collimator lens 50 is integrated. Alternatively, the fixed-side optical transmission system including the fixed-side optical fiber FB2 and the fixed-side collimator lens 42 may be configured as a single unit, and the rotation-side optical transmission system may be rotatably supported with respect to the fixed-side optical transmission system.

Schematic configuration diagram of an optical tomographic imaging apparatus using a rotary joint of the present invention Schematic cross section of rotary joint The front view which shows the shutter member of FIG. The front view which shows the connection member of FIG. Schematic sectional view showing the tip configuration of the optical probe Block diagram showing schematic configuration of processing unit Sectional drawing which shows the shutter member of a structure different from FIG. Schematic configuration diagram of an optical tomographic imaging apparatus of another embodiment

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10, 10a ... Optical tomographic imaging apparatus 11, 11a ... Apparatus main body, 12 ... Light source unit, 14 ... Branching / combining part, 14a ... Branching part, 14b ... Combining part, 16 ... Optical probe, 18, 18a ... Rotary joint , 20 ... interference light detection section, 22 ... processing section, 24 ... display section, 25a and 25b ... optical circulator, 26 ... optical path length adjustment section, 27a and 27b ... polarization controller, 28 ... optical fiber couplers, 30a and 30b ... Detection unit, 32 ... operation unit, 34 ... housing, 36 ... motor, 38 ... fixed sleeve, 42, 50 ... collimator lens, 44 ... bearing, 46 ... rotating sleeve, 52, 54 ... gear (gear), 56 ... shutter Member 57 ... Shutter 58 ... Doc 59 59 Shaft 60 Semiconductor optical amplifier 62 Optical splitter 64 Collimator lens 66 Grating element 67 Light System: 68 ... Rotating polygon mirror (polygon mirror), 70 ... Probe outer cylinder, 72 ... Cap, 74 ... Spring, 76 ... Fixing member, 78 ... Optical lens, 80 ... First optical lens, 82 ... Second optical lens, 84: reflection mirror, 86: base, 88 ... mirror moving mechanism, 90 ... interference signal acquisition unit, 92 ... A / D conversion unit, 94 ... contact state detection unit, 96 ... tomographic information generation unit, FB1, FB2, FB3 , FB4, FB5, FB6 ... optical fiber

Claims (7)

A fixed-side member that supports the end of the fixed-side optical fiber;
The fixed side member is rotatably provided, and detachably supports the end of the rotating side optical fiber in the OCT optical probe, and optically contacts the rotating side optical fiber and the fixed side optical fiber in a non-contact manner. A rotating member to be connected to,
A shutter member provided on an optical path formed between an end portion of the fixed side optical fiber and an end portion of the rotation side optical fiber, and opens and closes the optical path by a shutter , and is provided on the rotating member. for example Bei and the shutter member, the,
The rotating member is provided with an attaching / detaching portion that is attached / detached by rotating an end portion of the rotating side optical fiber,
The shutter member is
An engaging portion that engages with an end of the rotating optical fiber and rotates in conjunction with the end of the rotating optical fiber;
An opening and closing mechanism for opening and closing the shutter by rotating the engagement portion;
Rotary joint, characterized in that it comprises a. 2. The rotary joint according to claim 1 , wherein the shutter member is opened when an end portion of the rotation-side optical fiber is attached to the rotation member. 3. The rotary joint according to claim 1, wherein the shutter member closes when the end of the rotation side optical fiber is detached from the rotation member. 4. The shutter member includes urging means for urging the shutter in a closing direction, and the shutter is closed by the urging means when the end of the rotation side optical fiber is removed from the rotation member. The rotary joint according to any one of claims 1 to 3 . The rotary joint according to any one of claims 1 to 4 , wherein a collimating lens is disposed at an end of the fixed side optical fiber and an end of the rotation side optical fiber. According to any one of claims 1-5, characterized in that the cover glass is provided on an optical path is formed between the end portions of the stationary optical fiber and said rotary optical fiber Rotary joint. Light source means for emitting light;
A light splitting means for splitting the light emitted from the light source means into measurement light and reference light;
An optical probe for OCT that irradiates the measurement object with the measurement light and obtains reflected light;
A multiplexing unit that combines the reflected light and the reference light to obtain interference light;
Interference light detecting means for detecting the interference light;
Based on the frequency and intensity of the detected interference light, the reflection intensity at a plurality of depth positions of the measurement object is detected, and the tomographic image of the measurement object is acquired based on the intensity of the reflection light at each depth position. Tomographic image processing means,
The rotary joint according to any one of claims 1 to 6 , connected to a proximal end portion of the OCT optical probe;
An optical tomographic imaging apparatus comprising:

Images