JP3361132B2 - Optical tomographic imaging system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] BACKGROUND OF THE INVENTION 1. Field of the Invention
Optical tomographic imaging system for obtaining tomographic images of specimens
I do. [0002] 2. Description of the Related Art In recent years, when a living tissue is diagnosed,
Imaging equipment for obtaining optical information on the surface state of the fabric
Optical CT apparatus capable of obtaining optical information inside tissue
Has been proposed. [0003] This optical CT apparatus uses a picosecond pulse.
Then, information inside the living body is detected to obtain a tomographic image. However
To generate ultrashort pulse light on the order of picosecond pulses
Laser light sources are expensive, bulky, and cumbersome to handle. [0004] Recently, an object has been inspected using low coherence light.
OCT (optical co
For example, Science Tomography)
Vol. 254, 1178 (1991).
You. [0005] In the above-mentioned interference OCT,
Can be used for tissue near the body surface,
Information for diagnosing any internal tissue
In order to obtain
No, it is virtually impossible. The present invention has been made in view of the above points.
Light for diagnosing tissue inside the body cavity
Optical tomographic imaging system capable of obtaining tomographic images
It is intended to provide. [0007] [MEANS FOR SOLVING THE PROBLEMS] To achieve the above object
The present inventionLight ofThe tomographic imaging device emits low coherent light
Low-coherence light generating means for generating the low-coherence light
To guide the low coherent light generated by the step to the subject side
In particular, a complex for guiding the reflected light reflected on the subject side is provided.
Light guiding means having a number of optical fibers;
Low coherence in a given optical fiber out of a number of optical fibers
When the light is sequentially switched to guide the light and the emission position is changed,
To sequentially detect the reflected light reflected on the subject side
Light scanning means, reflected light detected by the light scanning means and the
Interfere with the reference light generated from low coherence light,
Light extracting means for extracting an interference signal corresponding to the generated interference light
When,PreviousSignal processing for the interference signalBefore doingOf the subject
Signal processing means for constructing a tomographic image in the depth direction;The signal
For the tomographic image constructed by the processing means,
At the time of light propagation that changes based on the above switching of the optical fiber
Calculating means for correcting distortion generated due toWith
It is characterized by doing. [0008] Embodiments of the present invention will be described below with reference to the drawings.
I do. FIG. 1 shows optical tomographic imaging according to a first embodiment of the present invention.
The device is shown. Optical tomographic imaging apparatus of the first embodiment
1 is an endoscope 2 capable of observing an arbitrary part in a body cavity, and
A light source device 3 for supplying illumination light to the endoscope 2;
The light guide member that guides light with low coherence provided in
And an optical interference device 4 for performing optical tomographic imaging,
As a display device for displaying an optical tomographic image by the interference device 4
And a monitor 5. The optical interference device 4 uses low-coherence light.
Interference light detection between measurement light and reference light to generate optical tomographic images
Outgoing interference unit 6 and interference obtained by this interference unit 6
Signal processing of electrical signals corresponding to light to respond to optical tomographic images
And a signal processing unit 7 for generating a video signal.
The image signal is displayed on the monitor 5. The endoscope 2 is an elongated and flexible insertion device.
Part 8 and a wide-width operation part provided at the rear end of the insertion part 8
9, an eyepiece 11 provided at the rear end of the operation unit 9,
A light guide cable extending from the side of the operation unit 9 to the outside
Bull 12. The insertion section 8, the operation section 9, and branching on the way
One light guide cable 12 has a light guide 1 inside.
3 is inserted, and the connector 14 at the proximal end thereof is connected to the light source device.
It can be detachably attached to the device 3. In this mounted state, the light source
For example, the white illumination light of the xenon lamp 15 inside the device 3 is
The light is collected by the condenser lens 16 and
This illumination light is transmitted by the light guide 13.
Other than being sent and fixed to the illumination window at the tip 17 of the insertion section 8
From the other end face forward through the illumination lens 18
Is done. Illumination light emitted through the illumination lens 18
Thus, the illuminated region of interest 19 such as the affected part is illuminated.
Objective lens 21 attached to the observation window adjacent to the lens 18
The optical image is formed on the focal plane. This focus
An image guide 22 having an image transmission function is provided at the position of the surface.
Of the image guide 22 is disposed.
Thus, the optical image is transmitted to the end face on the eyepiece section 11 side. An image guide is provided inside the eyepiece window of the eyepiece unit 11.
The eyepiece 23 is attached to the end face of the
The surgeon moves the eye closer to the eyepiece window,
Magnifying and observing the optical image transmitted through the
it can. The operating section 9 has a bending operating device (not shown).
There is a structure, and by operating the bending operation knob,
The curved portion formed at the rear end of the tip portion 17
The surgeon can bend in any direction, and the operator
Point the observation window of the tip 17 in a direction suitable for observation
be able to. The endoscope 2 is further polarized with low coherent light.
Polarization-maintaining fiber bundle 25 for transmitting while maintaining the wavefront
Is inserted. That is, the insertion unit 8, the operation unit 9, and the
Polarized light is maintained in the light guide cable 12 branched in
The fiber bundle 25 is inserted and the light guide cable
The connector 26 at the tip of the
It can be detachably attached to. This polarization maintaining fiber bundle 25 is, for example,
In the middle part, the cross section is circular, but at both ends the cross section is straight
N polarization-maintaining fibers are arranged in a
You. Also, as shown in FIG.
The array of 1,..., Fn is the fiber f1, at the other end.
.., Fn. A light source having low coherence arranged in the interference section 6
Ultra-bright light emitting diode (hereinafter abbreviated as SLD)
Note) At a wavelength of, for example, 830 nm, for example, a coherent distance
Light with a separation of about several tens to several thousand μm
a, a certain polarization plane through the polarizer 32b and the lens 32c.
It is converted into linearly polarized light, and the single mode optical fiber 33a
From one end face and transmitted to the other end face. The optical fiber 33a is a PANDA on the way.
The other single mode optical fiber 33b is connected to the coupler 34.
And optically coupled. Therefore, this coupler 34
It is split into two parts and transmitted. Optical fiber 33a
(From coupler 34) is the lead zirconate ceramic
Mix (abbreviated as PZT) 35
ing. The PZT 35 receives a drive signal from an oscillator 36.
Is applied, and by vibrating the optical fiber 33a,
A modulator 37 for modulating transmitted light is formed. This drive
The frequency of the motion signal is, for example, 5 to 20 KHz. Modulated
The emitted light is emitted from the end face of the optical fiber 33a,
The scanner 39 is connected via the lens 38 facing the distal end face.
Incident on the mirror 41. This mirror surface 41 is the scanner 39
Is rotated so that the incident angle changes. The light reflected by the mirror 41 is a cylinder.
The polarization maintaining fiber bundle 25 through the riical lens 42
, Fn. This polarization
The light is transmitted by the holding fiber bundle 25 and is
Are sequentially emitted from the end faces of the fibers f1,.
The part 19 is scanned substantially linearly. Site of interest 19 side
Is reflected by the polarization maintaining fiber bundle 25.
Transmitted, the cylindrical lens 42, the mirror 41 and
The light enters the distal end surface of the optical fiber 33a through the lens 38.
You. This light is almost half of the light output by the coupler 34.
Then, the light beam is guided to the (interference light) detection unit 44.
Also, this optical fiber 33b was attached to the tip surface.
The light reflected by the mirror 45 (light from the SLD 31 side
The reference light branched by the coupler 34 is also transmitted, and the detection unit 44
Lead to. In other words, the light guided to the detection unit 44 is polarization-maintaining.
Transmitted to the fiber bundle 25 side, and
The reflected measurement light and the reference light reflected by the mirror 45
Will be mixed. The mirror 4 in the optical fiber 33b
An optical fiber is provided between the tip fixed to
Wound to form the modulator 37 in the iva 33a
The optical path length at the portion and the polarization maintaining fiber bundle 25 side
Of the optical path length to almost compensate for the
A compensation ring 46 is provided. Rear end face of optical fiber 33b
The light emitted from the lens is converted into a parallel light beam by a lens 47 and analyzed.
After the light component on the polarization plane is extracted by the
The light is split into transmitted light and reflected light by the mirror 49. The reflected light is reflected by the mirror 51,
The light component transmitted by the half mirror 49 is)
Focused, silicon photodiode as photodetector
A light (abbreviated as Si-PD) 53 is received. Also, transmitted light
Is reflected by the mirror 55 attached to the X-stage 54.
(And the light component reflected by the half mirror 49)
The light is collected by the lens 52 and received by the Si-PD 53.
You. The X-stage 54 is, for example, a stepping module.
Facing the end face of the optical fiber 33b by the data 56
To move the optical path length on the reference beam side.
ing. The reference light reflected by the mirrors 45 and 55 is S
The optical path length until the light enters the i-PD 53 and the polarization maintaining
From a certain depth of the site of interest 19 through the fiber bundle 25
The returned measurement light is reflected by the mirror 51 and the Si-PD 53
When the optical path length until the light enters the
Interference light for that depth is detected, and thus the reference light
Optical tomography in the depth direction by changing the optical path length on the side
The interference light data for the formation is obtained. Incidentally, up to the half mirror 49 and the mirror 51
Path length and the optical path to the half mirror 49 and the mirror 55
Length should be at least out of the interference range of low coherence light
The light to be measured is half mirror
Half mirror after branching to transmitted light and reflected light at -49
49 is set so that interference does not occur. The signal photoelectrically converted by the Si-PD 53
After being amplified by the preamplifier 57,
The signal is input to the signal input terminal of the lock-in amplifier 58. This b
The reference signal input terminal of the
A drive signal or a signal having the same phase as the drive signal is input as a reference signal.
And the reference signal in the signal that has passed through the preamplifier 57
The same phase signal components are extracted and detected and amplified.
You. The output of the lock-in amplifier 58 is
Input to the computer 59 and the polarization maintaining fiber bundle 25.
Obtained by each fiber fi (i = 1 to n)
To generate a video signal corresponding to the tomographic image from the obtained signal
Control. That is, from the fiber f1 to the fiber fn
A control signal is sent to the scanner 39 so that light is sequentially input.
You. Light scans sequentially from fiber f1 to fiber fn
In this state, the signal input from the lock-in amplifier 58 is
Signal (converted to digital quantity by A / D converter)
For example, it is stored in an image memory (not shown). When scanning is completed up to the fiber fn,
A control signal is sent to the stepping motor 56 and the mirror 55
Is controlled to move a little. Again, the scanner 39
Control signal, and the light is sequentially transmitted from fiber f1 to fiber fn.
After the next scan, input from the lock-in amplifier 58.
The input signal is stored in the image memory. Like this
To store the signal for the predetermined depth range in the image memory.
When the operation is completed, the signals stored in the image memory are
Video processor 6 via D / A converter not shown
Output to 0. It should be noted that the light exits from the end face of the optical fiber 33a.
Light until the input light enters the end face of each fiber fi
The optical path length is such that the path length is small at the center and large at both ends.
Is different enough to deviate from the acceptable range,
Without correction, the tomographic image will be distorted.
The computer 59 performs a process for performing the correction. In the video processor 60, the computer 5
Standard by superimposing a synchronization signal on the signal input from 9
A typical video signal is generated and output to the monitor 5. Monitor 5
Displays an input video signal on a monitor screen. This model
The tomographic image 5a of the site of interest is displayed on the screen
Become. According to the first embodiment, the endoscope 2 has a low
By inserting a light guide member that guides coherent light,
Low-interference light can be guided to the site where
Can easily be obtained. Follow
From the surface condition of the part desired to be observed by the endoscope 2.
Obtain this tomographic image even when the information is insufficient
Provides information on the internal state,
It can provide information for making an accurate diagnosis. Also pico
This can be realized at lower cost than in the case of using the second pulse. FIG. 2 shows a main part of a first modification of the first embodiment.
Is shown. In this modification, a polarization maintaining fiber band
The end of the connector 25 on the connector 26 side is different. In other words, this
In a modification, the ends are arranged so as to form an arc, and
Polarization maintaining fiber emitted from the distal end face of fiber 33a
Optical path to the end of each of the fibers f1 to fn of the bundle 25
They are arranged so that their lengths are the same. In this modified example, cylindrical callen
Without using the mirror 42, the light reflected by the mirror 41
The light is incident (guided) on each fiber fi. Mirror 4
The actual light reflection position at 1 is set at the center of the arc
Is set to According to this modification, each fiber f
Since the respective optical path lengths when guided to i are equal,
It is possible to reduce the distortion of the obtained tomographic image.
There is a merit that the correction of can be omitted. FIG. 3 shows a main part of a second modification of the first embodiment.
Is shown. This modified example faces the connector 26 side end face.
A linear scanning mechanism 61 is provided. Optical fiber 33
a is fixed to the X-stage 62 with a fixing member 63.
Have been. The X-stage 62 has a lens 38.
And the mirror 64 are also fixed, and the distal end surface of the optical fiber 33a is fixed.
Light emitted from the lens passes through a lens 38 and is orthogonally formed by a mirror 64.
Polarization maintaining fiber bundle 2 reflected in the opposite direction
No. 5 fiber fi. The X-stage 62 is a stepping motor 6
5, the direction indicated by the arrow, that is, the polarization maintaining fiber
To scan in the direction parallel to the end face of the bundle 25
It has become. Also in this case, the end face of each fiber fi
The optical path length until the light is guided can be made constant. Therefore,
It has the same effect as the first modification. FIG. 4 shows a third modification of the first embodiment.
3 shows a part of the endoscope distal end side. Polarization-maintaining fiber bundle
The tip of each fiber fi 25 is a tip constituting the tip 17.
Each file is fixed to a hole provided in the end body 66, and
A selfoc lens 67 is formed in a line on the tip of the fi.
Are located. It should be noted that the self-
Observation window 21a and illumination window provided adjacent to back lens 67
18a has an objective lens 21 and an illumination lens 18 respectively.
It is attached. Light is efficiently emitted by the selfoc lens 67.
It guides light well forward along its optical axis,
Collects light incident from different directions and efficiently
The light is guided to the front end face of fi. According to this variant, the sensitivity and
And S / N can be improved. FIG. 5 shows a fourth modification of the first embodiment.
3 shows a part of the endoscope distal end side. In this modification, the tip
The body 66 has a circle adjacent to the observation window 21a and the illumination window 18a.
A through hole is formed, and a lens is formed inside the cover glass 68.
The optical fiber 69 is attached inside the lens 69.
The fi is stored as shown in the enlarged view of FIG.
ing. That is, the optical fiber fi is as shown in FIG.
Are stacked so that the vertical position is slightly shifted.
Disassembled than when placed vertically without stacking
Performance has been improved. FIG. 7 shows an optical tomographic image according to a second embodiment of the present invention.
2 shows a main part of a zing device 71. In the first embodiment, an endoscope
2 In addition to the usual illumination optical system and observation optical system, low interference
The light guide member for guiding the light of
In the example, the insertion part can be reduced in diameter by being provided integrally with the observation optical system.
I'm working. The endoscope 72 of this device 71
(Image Guide) Fiber Band Constructing Id 22
The polarization maintaining fiber bundle 25 is embedded in the fiber 22a.
In. For example, as shown in FIG.
2a, a polarization-maintaining fiber
Embedded so that the fibers f1 to fn of the handle 25 are arranged.
It is embedded. The polarization maintaining fiber bundle 25 is buried.
The objective lens faces the distal end surface of the inserted image guide 22.
21 is disposed, and a cover glass 74 is disposed in front thereof.
Have been. In this embodiment, the light guide 13 is
It is branched into two in the insertion portion 8, and each tip is a cover cover.
Turn diagonally so that illumination light can be emitted through lath 74
It is fixed in this way. The polarization maintaining fiber bundle 25 is an example.
For example, the operation unit 9 separates the image guide 22 from the image guide 22.
Inserted in a cable different from the light guide cable 12
(Through the light guide cable 12 as shown in FIG. 2)
And may be branched at the distal end), like in FIG.
The connector 26 at the end of the connection is connected to the interference unit 6.
Swelling. Other structures are the same as those described with reference to FIG. 1 or FIG.
Therefore, the same components are denoted by the same reference numerals.
Therefore, the description is omitted. In this embodiment, the polarization maintaining
Embed the Iva bundle 25 in the image guide 22 and watch
Independent optical system, independent of image guide 22
Than the case where the polarization maintaining fiber bundle 25 is provided.
The diameter of the entrance 8 can be reduced, and the measurement position can be confirmed.
There are benefits. Further, light is illuminated through a common cover glass 74.
Emit bright light and capture light for observation
As shown in FIG.
Lighting and observation are performed with the end face in close contact with the subject 75.
I can do it. Use in close contact
If this is the case, it is possible to prevent misalignment with the subject 75 during measurement.
As a result, a highly accurate optical tomographic image can be obtained. FIG. 10 shows an optical tomographic image according to the third embodiment of the present invention.
2 shows a main part of the easing device 81. In this embodiment, scanning
Multiple optical tomographic images with different directions can be obtained
It is. The endoscope 82 of this embodiment is a normal illumination optical system.
Transmits two low-interference lights in addition to the system and observation optics
Fiber bundles 25A and 25B to be inserted
At the tip portion 17 of the portion 8, for example, as shown in FIG.
The two fiber arrays 83A and 83B arranged in
Have been. The fiber at the center of the cross in FIG. 11 is common
Used for The fiber bundles 25A and 25B are operating units.
9 is inserted through the cable 84 extending from
Are connected to the interference unit 85. Fiber bundle 25A,
The ends of 25B are arranged in an arc shape as described with reference to FIG.
Is placed. That is, the light is drawn on a circle centered on the mirror 41.
The two ends are arranged facing each other so that the end of the
41 is rotated by a motor (not shown),
Optical fibers are connected to the fibers f1 to fn and f1 'to fn' at each end.
The low coherence light from the iva 33a side is transmitted through the lens 38.
The optical fiber guides the light and reflects the light reflected on the subject side.
The light is guided to the side 33a. The interference unit 85 of this embodiment is the same as that of the first embodiment.
The configuration may be the same as that shown in FIG.
No. In FIG. 10, the light from the SLD 31 is the light from the lens 32.
The light is incident on one end face of the fiber 33a, and a part thereof is
Via a coupler 34 branched to an optical fiber 33b,
Further, through the modulator 37 formed of PZT35 or the like,
From the mirror 41. For example, the mirror 41 shown by a solid line in FIG.
In this state, the light is guided to the fiber bundle 25A side,
The light is emitted from the array 83A toward the subject in front, and
And part of the light reflected inside enters the same fiber fi
Is done. This light is reflected by the mirror 41 and the coupler 34
To the other optical fiber 33b via Si-PD, etc.
Is received by the photodetector 86. On the other hand, the light of the SLD 31 passes through the coupler 34.
Into the other optical fiber 33b,
Through the lens 87 from the distal end face of the optical fiber 33b
The light is collected and emitted. This light is reflected by the mirror 45
The optical detection is performed as reference light from the rear end face of the optical fiber 33b.
The light is received by the output device 86. The mirror 45 is connected to a scanning mechanism (not shown).
And move as shown by the arrow, and the optical path length on the reference
Changed. The optical path length of the measurement light returning through the endoscope 82 is
When it almost matches the optical path length on the reference light side, it is detected as interference light.
Detected by the output unit 86 and output to the signal processing unit 7 shown in FIG.
The signal is processed, and a tomographic image is displayed on the monitor 5.
You. In this case, as shown by the solid line SA in FIG.
In response to scanning, for example, the left side of the monitor 5 as shown in FIG.
Is displayed as a tomographic image GA. In the state of the mirror 41 shown by the dotted line in FIG.
The light is guided to the fiber bundle 25B side, and the fiber array
83B is emitted toward the subject in front, and on the surface and inside
A part of the reflected light is the same fiber fi′Incident on
You. This light is reflected by the mirror 41, and
34, and the other optical fiber 33b is transferred to the Si-PD
The signal processing unit 7 shown in FIG.
Output, signal processed, and tomographic image displayed on monitor
Is done. In this case, as shown by the dotted line SB in FIG.
In response to the scanning in the direction, for example, as shown in FIG.
The tomographic image GB is displayed on the right side. FIG. 14 shows an endoscope according to a modification of the third embodiment.
9 shows a fiber support member 91 fixed to a mirror tip. Insertion
A through hole is formed at the tip of the entrance, and the through hole
The support member 91 is fixed with an adhesive or the like. The fiber support member 91 has a cross shape.
Holes are formed in the fiber array 83A.
Between the fi and the fiber fi 'of the fiber array 83B.
The tip side is inserted and fixed with an adhesive or the like. Each
The end faces of fibers fi and fi 'are respectively selfoc
A lens 92 is attached. FIG. 15 is a schematic diagram showing a fourth embodiment of the present invention.
FIG. 15A is a front view, and FIG.
FIG. 16 is a sectional view taken along the line AA ′ of FIG. This pro
Bulb 93 is normally equipped with observation window 94a and illumination window 94b.
Probe that can be inserted into the channel 94c of the endoscope 94
It is. Light with low coherence is guided into the probe 93.
The optical fiber bundle 95 that emits light is inserted,
The tip of the bundle 95 is attached to the tip of the probe 93
Fixed by an optical fiber array support member 96. The optical fiber array support member 96 is shown in FIG.
(B) As shown in FIG.
The tip of the fiber bundle 95 is inserted into the hole provided along the arc.
Is inserted and fixed. Therefore, as shown in FIG.
As shown, the tip of the fiber bundle 95 is curved along an arc.
The optical fiber array 95a is arranged on the line.
You. FIG. 16 is a front view of the optical fiber array 95a.
Is shown. Of the optical fiber array support member 96
The direction perpendicular to the tangent direction of the curved surface of the porosity δ, that is, the normal direction
Holes are provided in each hole, and each light of the fiber bundle 95 is provided in each hole.
The fiber is inserted and secured. Therefore, each optical fiber
Fiber is oriented perpendicular to the tangent of the curved surface
become. According to this embodiment, as shown in FIG.
An optical tomographic image of a fan-shaped visual field is obtained. The dotted line in FIG.
For example, the field of view obtained by the first embodiment,
The example shows that a wider field of view can be obtained than in each of the above-mentioned embodiments.
There is an advantage. FIG. 18 shows a program of a first modification of the fourth embodiment.
Shows the head 93 '. This variant is to improve the resolution
The vertical position of the optical fiber array little by little.
It is a laminate. FIG. 19 shows an optical fiber according to a second modification of the fourth embodiment.
A fiber array support member 96 'is shown. This modification is an optical fiber
Selfoc lens 97 is arranged in front of fiber array
It has a structure. FIG. 20 is a diagram showing a program according to the fifth embodiment of the present invention.
FIG. 20A is a front view, and FIG.
20 (b) is a sectional view taken along line BB 'of FIG. 20 (a).
In this embodiment, an optical tomographic image in a side view direction can be obtained.
Things. For example, using the probe 93 shown in FIG.
When trying to obtain an optical tomographic image in the side viewing direction,
Must be greatly curved (bent). This place
In this case, it becomes difficult to bend in the esophagus and the like. like this
Suitable for using this probe 101 in some cases
Become. In this probe 101, light having low coherence is provided.
The optical fiber bundle 102 for guiding light is inserted,
The tip of the fiber bundle 102 is the tip of the probe 101
Optical fiber attached to the opening provided on the side surface of member 103
It is fixed by the array support member 104. This optical fiber array support member 104 is
It has a curved surface 104a curved at a constant porosity ρ,
04a has many holes in the direction parallel to the axis of probe 101
Formed eachHoleEach optical fiber of the optical fiber bundle 102
Direction is parallel to the axis of the probe 101
The optical fiber array 105 is formed at the bottom. The optical tomographic image obtained by this embodiment is shown in FIG.
As shown in Fig. 1, it corresponds to a field of view that spreads fanwise with depth.
It will be. It should be noted that an optical fiber
A cell as shown in FIG.
A Fock lens may be provided. Also, along the curved surface
Has a wide-angle field of view with the optical fiber array 105
Not only objects but also light sources in the side viewing direction
A layer image may be obtained. FIG. 22 shows an optical tomographic image according to the sixth embodiment of the present invention.
FIG. Optical tomographic image shown in FIG.
Zing device 111 can be elongated and inserted into the subject.
Flexible insertion section 112 and light for tomographic image observation
Emits light and receives reflected light from inside the subject
An interference unit 113 and a signal for processing the output of the interference unit 113.
Signal processing unit 114 and the signal processing unit 115
And a monitor 115 for displaying a video signal. The insertion section 112 is used to insert an endoscope, for example.
Channel portion 116 of the tip portion 116
a, the illumination window 117, the observation window 118, and the suction channel.
And the like 119 are formed. A light distribution lens is provided inside the illumination window 117.
A light guide 120 is attached to the rear end of the light distribution lens.
Are connected. The light guide 120 has an insertion portion
112 and is connected to a light source device (not shown),
The illumination light from this light source device is transmitted and transmitted through the illumination window 117.
Irradiation is performed on the observation site of the subject. The observation window 118InsideHas an objective lens
121, an image forming position of the objective lens 121.
, A tip surface of the image guide 122 is disposed.
The image guide 122 is inserted through the insertion portion 112.
The rear end face faces the eyepiece in the eyepiece (not shown).
ing. Then, the image was formed by the objective lens 121.
The optical image of the observation site is guided by the image guide 122
Thus, the naked eye can be observed from the eyepiece. Further, the insertion section 112 is used for observation of tomographic images.
Optical fiber bundle 1 as a means for scanning the light radially
23, and this optical fiber bundle 123 is
12, a plurality of optical fibers 123a are annularly disposed on the outer peripheral side.
It is composed. As shown in FIGS. 22 and 23,
The distal end of the optical fiber 123a is
It is arranged so as to surround the channel portion 116a,
As shown in FIG. 24, the tip surface is
For example, it is cut at 45 ° to form a tapered surface 123b.
ing. The tapered surface 123b is made of aluminum.
Mirror surface is formed by depositing nickel, silver, gold, etc.
At the same time, this mirror surface is
The light from the optical interference device 113 is arranged in a fiber
Reflected to the side of the axis and reflected from inside the subject
Light is made to enter in the fiber axis direction. Ma
The end of the optical fiber bundle 123 is provided inside the interference section 113.
The mirror 124a of the galvanometer 124 faces the portion
Are located. This galvanometer 124 is a control circuit
125. That is, the light is emitted from the end face of the optical fiber 33a.
The emitted light is passed through a lens 38 to the end of an optical fiber bundle 123.
Mirror 124 so as to guide the light sequentially to each optical fiber of the section.
The swing angle of a is variably controlled. In this state, the object side
The emitted light passes through an optical fiber 33a through a lens 38.
The light is incident on the end face. Other of interference unit 113
The configuration is the same as that shown in FIG. 10, for example.
Description is omitted. The output of the photodetector 86 of the interference section 113 is a signal
The signal is input to the processing unit 114, subjected to signal processing, and
A corresponding video signal is generated, and an optical tomographic image is
Is displayed. The optical fiber 123a has a tapered end.
Although the surface 123b is formed, instead of the tapered surface 123b,
A prism may be arranged, and the optical fiber 123a
Instead, as shown in FIG.
Optical fiber 123a 'bent outward from entrance 112
May be used to form the optical fiber bundle 123. Next, optical tomographic image observation using this device 111
Will be described. For example, an optical tomographic image of the affected part of a human organ
First, insert the insertion section 112 into the body cavity
I do. Next, the outer peripheral side of the distal end portion 116 reached the affected part position.
Of the SLD 31 in the interference unit 113
The optical fiber bundle 12 is reflected by the mirror 124a of the optical fiber bundle 124.
3 is made to enter each optical fiber 123a. The light incident on each optical fiber 123a is
Reflected by the tapered surface 123b at the tip, the side of the fiber axis
And emitted outward from the optical fiber bundle 123.
Optical scanning is performed radially. And the light illuminated on the affected area
When light is reflected on and inside the tissue, this reflected light
Mirror 1 of the galvanometer 124 from the fiber bundle 123
24a, the light is guided into the interference unit 113, and the internal lens
38, the optical detector 86 via the optical fibers 33a and 33b.
Is incident on. The output of the photodetector 86 is sent to the signal processing unit 11
Video signal corresponding to the optical tomographic image of the observation site
The optical tomographic image is displayed on the monitor 115. This fruit
According to the embodiment, the insertion section 112 is inserted into the subject and cut.
When observing a layer image, complicated bending operation of the insertion section 112 is required.
The outer periphery of the distal end portion 116 of the insertion portion 112 without requiring any operation
Side only to the observation site and release it from the insertion section 112.
Since light scanning is performed in a radial pattern, light interruption at the desired observation site
A layer image is easily obtained. FIG. 26 shows an insertion portion according to a modification of the sixth embodiment.
You. In this modified example, not the entire circumference of the tip 116 but only a part thereof
An optical fiber bundle 123 is provided for transmitting and receiving light in a fan shape.
This is to obtain a tomographic image. FIG. 27 shows an optical tomographic image according to the seventh embodiment of the present invention.
FIG. This optical tomographic imaging system
The position 161 is an endoscope 16 capable of observing an arbitrary part in a body cavity.
2 and a light source device 3 for supplying illumination light to the endoscope 162
Guides light of low coherence provided in the endoscope 162.
Light guide member is connected to
Interfering device 164 and an optical tomographic image by the optical interference device 164
And a monitor (not shown) for displaying The light interference device 164 uses light having low coherence.
Section for detecting interference light for generating optical tomographic images
166 and the interference light detected by the interference unit 166
Image signal corresponding to the optical tomographic image
And a signal processing unit 167 for generating a signal. The endoscope 162 is similar to the endoscope 2 shown in FIG.
The connector 26 of the polarization maintaining fiber bundle 25
Each side has a hole formed along the circumference of the disk.
It is inserted and fixed with an adhesive or the like. The interference section 166 of this embodiment is the same as that shown in FIG.
In the embodiment, an optical tomographic image was obtained with one wavelength of light.
On the other hand, in this embodiment, light of three wavelengths
You will get an image. For this reason, the three SLDs 31-1 and 31-1
2, 31-3 form a light-generating portion, and these are, for example, 7
Generates light of each wavelength of 60nm, 790nm, 840nm
And a lens 32a, a polarizer 32b, a dichroic
Optical fiber 3 through the optical mirror 32d and the lens 32c.
The light is guided to 3a. The optical fiber 33a faces the distal end face of the optical fiber 33a.
Optical rod 1 with lens 38 and gear 171 attached
72 is disposed at one end thereof, and this gear 171 is provided with an intermediate gear.
Gear 1 attached to the shaft of motor 174 via gear 173
75 is engaged. Then, the motor 174 rotates.
And the connector 26 side of the polarization maintaining fiber bundle 25
The end of the optical rod 172 is attached to the end face of each of the optical fibers f1 to fn.
The end faces face each other, and the light on the optical fiber 33a side is
The light is guided to the polarization maintaining fiber bundle 25 side, and
The light from the wave holding fiber bundle 25 side is
The light is guided to the side 3a. The motor 174 is connected to a two-axis driver 176.
A drive signal for more rotational drive is supplied. This 2-axis drive
The drive 176 sends a drive signal to the motor 56 of the X stage 54.
Supply. The supply of the drive signal to the motors 174 and 56 is
It is controlled by the computer 59. Detecting light emitted from optical fiber 33b
Detection unit 177 can also separate and detect light of three wavelengths.
Configuration. That is, the reflected light of the mirror 51
The light reflected by the mirror 55 is mixed by the half mirror 49 and
Selectable according to the wavelength of light with the ichroic mirror 178
Transmitted / reflected, and further through the analyzer 48 and the lens 52
With Si-PD53-1, 53-2, 53-3 respectively
Received. Si-PD53-1, 53-2, 53-3
Are amplified by a preamplifier 57, respectively,
The signal is input to the lock-in amplifier 58 of the processing unit 167. This
The lock-in amplifier 58 has one input in FIG.
There are 3 channels to support 3 inputs.
Channels are sequentially selected and operated in time division. The other points are the same as in the embodiment of FIG. This
In the embodiment, optical tomographic images are obtained with three wavelengths of light, respectively.
There are benefits. In addition, the optical rod is
172 only rotates the polarization maintaining fiber bundle 2
The light can be sequentially guided to the five optical fibers f1 to fn. That is,
It is easy to sequentially guide light to the optical fibers f1 to fn.
be able to. By the way, the intestines and other organs are stapled with a stapler.
When cutting after pulling, the tissue at the staple
If you are dead, there is a risk that the staples will fall out after surgery
The stapled tissue is alive
A machine that allows you to know in advance if it is dead by measuring
A structure may be provided. Stapler 1 equipped with this mechanism
31 is shown in FIG. The stapler 131 is used for a lumen such as an intestine.
And a stapler 133 for stapling the container 132.
The optical fiber bundle 134 provided on the stapler 133 is
135, connected via connector 136, tomographic image
Imaging apparatus 137 that performs signal processing for obtaining
Is connected to the imaging device 137 to break tissue.
Computer 138 that performs arithmetic processing for determining whether or not a person is dead
And a display device that displays tomographic images and the results of necrosis determination
139. At the tip of the stapler 133, FIG.
Cart with anvil 141 installed as shown enlarged
A ridge 142 is attached. This car
Longitudinal direction of stapled portion of cartridge 142
The fiber array 134a is formed in
You. FIG. 30 shows the surface to be stapled. The fiber adjacent to the cutter guide groove 144
An array 134a is formed, and the part of the tissue to be cut is necrotic
While emitting light to determine whether or not reflected light is
I am able to do it. Also, the cutter guide groove 144 and
For forming staples on both sides of the fiber array 134a
The staple forming groove 145 is provided. FIG. 31 shows the configuration of the imaging device 137.
Show. This imaging device 137 is the interference unit 8 shown in FIG.
5, means for generating light of two wavelengths and light of each wavelength
It has means for detecting light. SLDs 31-1 and 31-2 are different from each other
It generates light of wavelengths, for example, 750 nm and 800 nm,
Each light is transmitted through a lens 32a and a dichroic mirror 14.
7. The light is guided to the optical fiber 33a through the lens 32c.
You. The light guided to the optical fiber 33a is
Polarization maintaining fiber through a lens 38 and a mirror 41
At the end of the optical fiber on the connector 136 side of the bundle 134
Incident. The end face of the optical fiber on the connector 136 side is
It is formed in an arc shape as described with reference to FIG. The transmission by the polarization maintaining fiber bundle 134 is performed.
The light reflected by the body cavity organ 132 is again polarized
The fiber bundle 134 transmits the optical fiber
The light is guided to the tip end surface of 33a. This light is emitted by coupler 34
A part is guided to the other optical fiber 33b,
Emitted from the end face, lens 148, dichroic mirror
149, through the lens 150, the photodetectors 86-1, 86
-2. The outputs of the photodetectors 86-1 and 86-2 are pre-
After being amplified by the amplifier 57, the lock-in amplifier
58 is input. Detected by lock-in amplifier 58
The signals are respectively compiled through the A / D converter 151.
Input to the computer 59. This computer 59 rotates the mirror 41.
Performs control and movement control of the mirror 45, etc., and responds to tomographic images
Obtained image data. This image data is
Computer 138, and the computer 138
Performs arithmetic processing to analyze data obtained at two wavelengths
From the tissue portion facing the fiber array 134a.
It is determined whether or not the received data corresponds to necrosis. FIG. 32 shows the wavelength of hemoglobin in blood.
Extinction characteristics. When hemoglobin has oxygen
(B) and the case without (a) have two wavelengths
The necessity of necrosis can be determined from the difference in the dimming degree. Toes
For light with a wavelength of 800 nm, hemoglobin is acid
If you have a prime
In other words, it is almost the same as tissue that has died without blood circulation
It shows the dimming characteristic. On the other hand, for light having a wavelength of 750 nm,
If hemoglobin has oxygen than it does not
Also shows a characteristic that the dimming degree (hereinafter referred to as OD) is small. Ma
When hemoglobin has oxygen, the wavelength is 750.
800nm light than OD (750) by nm light
OD (800) is large. That is, OD (750) <OD (800) Becomes On the other hand, when hemoglobin has no oxygen
Shows the opposite trend. That is, OD (750)> OD (800) Becomes Therefore, as described above, it is possible to obtain two wavelengths.
By comparing the reflected intensity data,
It is easy to determine when oxygen has oxygen or no oxygen.
Can be turned off. If three wavelengths and four wavelengths are used,
Mb and cytochrome can be detected in addition to the bottle. In the above embodiment, the optical path length is changed.
When performing the conversion, it is limited to the one performed on the reference
Instead of changing the optical path length on the measurement light side.
You may. [0108] 【The invention's effect】As described above, according to the present invention,
It is possible to obtain a tomographic image in the depth direction of the subject by invasion.
Wear.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration diagram of an optical tomographic imaging apparatus according to a first embodiment of the present invention. FIG. 2 is a configuration diagram of a main part of a first modified example of the first embodiment. FIG. 3 is a configuration diagram of a main part of a second modified example of the first embodiment. FIG. 4 is a cross-sectional view showing a distal end side of an endoscope in a third modified example of the first embodiment. FIG. 5 is a cross-sectional view showing a distal end side of an endoscope in a fourth modified example of the first embodiment. FIG. 6 is a diagram showing a state in which optical fibers are stacked. FIG. 7 is a configuration diagram of a main part of an optical tomographic imaging apparatus according to a second embodiment of the present invention. FIG. 8 is a diagram showing a distal end surface of an image guide. FIG. 9 is a diagram showing a state in which a distal end surface of an insertion section is brought into close contact with a subject. FIG. 10 is a configuration diagram of a main part of an optical tomographic imaging apparatus 81 according to a third embodiment of the present invention. FIG. 11 is a diagram showing a distal end surface of an endoscope insertion section. FIG. 12 is an explanatory view showing a surface scanned by an optical fiber array. FIG. 13 is a view showing that two tomographic images are displayed on a monitor. FIG. 14 is a perspective view showing a fiber support member fixed to a distal end portion of an endoscope in a modification of the third embodiment. FIG. 15 is a view showing a probe according to a fourth embodiment of the present invention. FIG. 16 is an explanatory diagram showing an arrangement of the tip of an optical fiber. FIG. 17 is a view showing a fan-shaped tomographic range obtained by a fourth embodiment. FIG. 18 is a diagram showing a distal end side of a probe according to a first modification of the fourth embodiment. FIG. 19 is a diagram showing an optical fiber array support member according to a second modification of the fourth embodiment. FIG. 20 is a front view showing a distal end side of a probe according to a fifth embodiment of the present invention. FIG. 21 is a diagram showing a fan-shaped tomographic area obtained by a fifth embodiment. FIG. 22 is a configuration diagram showing an optical tomographic imaging apparatus according to a sixth embodiment of the present invention. FIG. 23 is a view showing a state in which a plurality of optical fibers are annularly arranged on the outer periphery of the insertion portion. FIG. 24 is a diagram showing that the distal end surface of the optical fiber is a tapered surface. FIG. 25 is a diagram showing a distal end side of an optical fiber in a modification. FIG. 26 is a diagram showing a state in which a plurality of optical fibers are provided around the outer periphery of the insertion section. FIG. 27 is a configuration diagram showing an optical tomographic imaging apparatus according to a seventh embodiment of the present invention. FIG. 28 is an overall configuration diagram of a stapling apparatus. FIG. 29 is a diagram showing a state in which an optical fiber array is provided on the tip side of the stapler. FIG. 30 is a diagram showing a configuration of a cut surface on the distal end side of the stapler. FIG. 31 is a configuration diagram of an imaging apparatus. FIG. 32 is a diagram showing a schematic dimming characteristic with respect to the wavelength of hemoglobin in blood. [Description of Signs] 1 ... optical tomographic imaging device 2 ... endoscope 3 ... light source device 4 ... optical interference device 5 ... monitor 6 ... interference unit 7 ... signal processing unit 8 ... insertion unit 9 ... operation unit 11 ... eyepiece unit 12 light guide cable 13 light guide 15 xenon lamp 17 tip 21 objective lens 22 image guide 23 eyepiece 25 polarization maintaining fiber bundle 26 connector 31 SLD 32b polarizers 33a and 33b Fiber 34 Coupler 35 PZT 36 Oscillator 37 Modulator 39 Scanner 41 Mirror surface 42 Cylindrical lens 44 Detector (interference light) 45 Mirror 48 Analyzer 49 Half mirrors 51 and 55 Mirror 53 ... Si-PD 54 ... X-stage 56 ... Stepping motor 57 ... Preamplifier 58 ... Lock-in amplifier 59 ... Computer 60 Video processor

──────────────────────────────────────────────────続 き Continuation of the front page (72) Kuniaki Kami, Inventor 2-43-2 Hatagaya, Shibuya-ku, Tokyo O-limpus Optical Industry Co., Ltd. 43-2 O Olympus Optical Industrial Co., Ltd. (72) Inventor Tetsumaru Kubota 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inventor Koji Yasunaga 2 (72) Inventor, Koji Yasunaga 2 Chome 43-2 O Olympus Optical Industrial Co., Ltd. (72) Inventor Atsushi Osawa 2-43-2 O Olympus Optical Industrial Co., Ltd. (72) Inventor Kazushi Ohashi Hatagaya, Shibuya-ku, Tokyo 2-43-2 O Olympus Optical Industrial Co., Ltd. (72) Inventor Yoshinao Daiaki 2-43-2 Hatagaya, Shibuya-ku, Tokyo O-limpus Hikari (56) References WO 92/19930 (WO, A1) (58) Fields investigated (Int. Cl. ⁷ , DB name) A61B 10/00

Claims (1)

(57) [Claims 1] Low coherence light generating means for generating low coherence light; and low coherence light generated by the low coherence light generation means is guided to the subject side. A light guiding unit having a plurality of optical fibers for guiding the reflected light reflected on the subject side; and the low coherence light being transmitted to a predetermined optical fiber among the plurality of optical fibers of the light guiding unit. The light scanning means for sequentially switching and guiding the light, changing the emission position, and sequentially detecting the reflected light reflected on the subject side, the reflected light detected by the light scanning means and the low coherence light by interfered with the reference light generated from the interference light extracting means for extracting an interference signal corresponding to the interference with interference light, the pre-Symbol tomographic image in the depth direction before Symbol subject performs signal processing for interference signals A signal processing means to be constructed; For the constructed tomographic image,
Changes based on the switching of the plurality of optical fibers
Arithmetic means for correcting distortion caused by light propagation time
When the optical tomographic imaging apparatus, comprising a.