JP2007117192A - Infrared observation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an infrared observation system which can acquire the observation image of the running state of a blood vessel on the deep part side of a living body with a good quality. <P>SOLUTION: An object lens 15 is arranged at the distal end 13 of the insertion part 11 of an endoscope body 4 and the optical image is picked up by an imaging element 18 for infrared imaging arranged within an infrared camera 5 through an image guide 16. A slide section 21, which composes an illumination unit 3 and can be slid, is attached to the insertion part 11, and a LED unit 22 in a circle form is attached to the distal end of this slide section 21 after alignment is carried out so as to be opposite to the visual field direction the object lens 15, so that transmitted light at the time of illuminating the living body 2 is efficiently entered into the object lens 15. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an infrared observation system suitable for observing a running state of a blood vessel in a deep part of a living body as a subject.

Conventionally, as a technique for identifying a subject to be observed, specifically, blood vessel travel of a living body, there is a method of observing using a hemoglobin absorption characteristic of 700 nm to 1000 nm in the near infrared wavelength region.
For example, Japanese Patent Application Laid-Open No. 2004-358051 as a first conventional example uses a characteristic that blood hemoglobin absorbs infrared light, and observes blood vessels of living tissue that are difficult to observe with visible light using infrared light. A technique for obtaining an image that is easy to perform is disclosed.
In addition, Japanese Patent Laid-Open No. 2005-87728 as a second conventional example discloses a fluorescent labeling substance administered to a living body using a light emitting element that generates light of any narrow wavelength band belonging to a range of 600 nm to 2000 nm. A capsule optical sensor incorporating a sensor for detecting fluorescence is disclosed.
JP 2004-358051 A Japanese Patent Application Laid-Open No. 2005-87728

In the first conventional example, since the wavelength in the range of 700 nm to 1000 nm is used, it is difficult to observe the blood vessels in the deep part of the living tissue.
Further, in the second conventional example, the capsule optical sensor is provided with a sensor that simply detects the presence or absence of the fluorescence wavelength, and therefore cannot obtain an image for knowing the running state of the blood vessel.

(Object of invention)
The present invention has been made in view of the above-described points, and an object thereof is to provide an infrared observation system that can obtain an observation image of a running state of a blood vessel on the deep side of a living body with good image quality.

An infrared observation system according to the present invention includes illumination means for irradiating a living body to be observed with illumination light in an infrared region longer than a wavelength of at least 1200 nm;
An imaging means provided with an imaging element that is arranged at an imaging position of an objective optical system that connects optical images or an imaging position that transmits an optical image by the objective optical system and has sensitivity in an infrared region longer than a wavelength of 1200 nm;
Signal processing means for performing signal processing on an imaging signal by the imaging means;
Alignment means for aligning the illumination means relative to the objective optical system.
With the above configuration, when illumination light in an infrared region longer than a wavelength of 1200 nm is irradiated on a living body, alignment is performed so that incident light imaged by the imaging unit through the living body is efficiently incident on the objective optical system. Therefore, an observation image such as a running state of a blood vessel in a deep part of a living body can be obtained with a good image quality.

  ADVANTAGE OF THE INVENTION According to this invention, the observation image of the running state of the blood vessel of the deep part of a biological body can be obtained in a state with favorable image quality.

  Embodiments of the present invention will be described below with reference to the drawings.

1 to 5 relate to the first embodiment of the present invention, FIG. 1 shows the overall configuration of the infrared observation system of the first embodiment of the present invention, and FIG. 2 shows the illumination unit on the distal end side of the insertion portion of the endoscope. 3 shows a configuration of a modified example in which the illumination direction in the illumination unit is changed. FIG. 4 shows a schematic image example obtained by the present embodiment in comparison with the case of visible light. 5 shows a characteristic example of a measurement result indicating that fat permeability can be increased after heat irradiation as compared to before heat irradiation.
As shown in FIG. 1, the infrared observation system 1 according to the first embodiment of the present invention includes an illumination unit 3 that irradiates a living body 2 as an object to be observed with light including an infrared region with illumination light. For example, an optical endoscope main body 4 provided and an infrared imaging camera (hereinafter simply abbreviated as an infrared camera) 5 attached to the endoscope main body 4 and imaging with light in the infrared region are provided. The endoscope 6 includes a camera control unit (abbreviated as CCU) 7 that performs signal processing on an image signal captured by the infrared camera 5, and a monitor 8 that displays a video signal output from the CCU 7. The

The endoscope main body 4 has an elongated and hard insertion portion 11 to be inserted into a body cavity, and an infrared camera 5 is attached to a rear end portion 12 of the insertion portion 11. A transparent hood 14 is attached to a distal end portion 13 provided at the distal end of the insertion portion 11, and an objective lens 15 having a direction parallel to the axis of the insertion portion 11 as a visual field direction is disposed inside the transparent hood 14. A front end surface of the image guide 16 is disposed at an image formation position by the objective lens 15, and the image guide 16 transmits an optical image formed on the front end surface to the rear end surface.
The optical image transmitted to the rear end surface of the image guide 16 is imaged on the infrared image sensor 18 through the imaging lens 17 disposed at a position facing the rear end surface of the image guide 16. This infrared imaging device 18 has sensitivity in an infrared region exceeding a wavelength of at least 1200 nm, for example, Ex. This is an imaging element formed using a semiconductor detection element (photovoltaic semiconductor detection element) such as InGaAs, InAs, or InSb.

These image sensors have sensitivity up to a wavelength band from at least 1200 nm to around 2550 nm. Note that InAs and InSb are sensitive to long wavelengths longer than 2550 nm and longer than 3000 nm.
In addition, the illumination unit 3 is attached to the endoscope body 4 in the present embodiment so as to be slidable in the axial direction of the insertion portion 11.
The illumination unit 3 has a cylindrical slide portion 21 that is slidable by being fitted to the outer peripheral surface of the outer tube that forms the insertion portion 11, and a support rod that extends from the tip of the slide portion 21. An annular LED unit 22 provided with a plurality of LEDs 22a for generating illumination light in the infrared region is attached to the tip of the LED unit 22 through the position 21a.
As each LED 22a, an LED that emits light in a wavelength region including an infrared region on the long wavelength side longer than 1200 nm in the infrared region is employed.

Moreover, the rear end side of this slide part 21 is arrange | positioned, for example inside the cylinder part 23 provided in the infrared camera 5, and the coil spring 24 is arrange | positioned in the space between both. The lighting unit 3 is biased toward the rear side of the insertion portion 11 by the coil spring 24. In addition, convex portions for retaining are formed at the front end of the cylindrical portion 23 where both ends of the coil spring 24 abut and the rear end portion of the slide portion 21.
In addition, a slide lever 25 for performing a slide operation is provided at a position near the rear end of the slide unit 21, and a user such as an operator operates the slide lever 25 in the direction of the arrow to insert the insertion unit 11. The illumination unit 3 side can be slid in the axial direction.

A signal line (power line) 26 connected to each LED 22 a of the LED unit 22 is inserted through the slide portion 21 and connected to the CCU 7 through the camera cable extended from the infrared camera 5.
The CCU 7 includes an image sensor driving circuit 27 that drives the infrared image sensor 18, a signal processing circuit 28 that performs signal processing on the image sensor output signal output from the image sensor 18, and an LED that causes the LED 22 a of the LED unit 22 to emit light. And an LED power supply circuit 29 for supplying power.
The video signal generated by the signal processing circuit 28 is output to the monitor 8, and an image captured by the image sensor 18 is displayed on the display surface of the monitor 8. The LED power supply by the LED power supply circuit 29 is applied to each LED 22a of the LED unit 22 via the signal line 26, and the LED 22a generates light in the infrared region.

FIG. 2 is a perspective view of the distal end portion of the endoscope body 4. As shown in FIG. 2, alignment (positioning) is performed along the optical axis O (or field of view) direction of the objective lens 15 (so as to face the objective lens 15) so that the observation range of the objective lens 15 can be effectively illuminated. The made LED unit 22 is provided in an annular shape. That is, the LED unit 22 is positioned and positioned so as to face the distal end surface of the insertion portion 11, and is movable in the visual field direction of the objective lens 15 in this arrangement state.
A large number of LEDs 22 a are arranged on the circular rear surface of the LED unit 22 along the circumference, and the LED unit 22 is integrated with the tip of the support bar 21 a protruding from the tip surface of the slide portion 21. It is fixed.
Each LED 22a expands the light at a predetermined angle θ toward the rear objective lens 15 and emits the light. That is, each LED 22a emits illumination light to the rear side in parallel with the visual field direction of the objective lens 15 (or the direction of the optical axis O). FIG. 2 shows an angle θ at which illumination light emitted from one LED 22a arranged in a circumferential shape is emitted.

The inner diameter of the annular shape of the LED unit 22 is set larger than the outer diameter of the distal end portion 13 of the insertion portion 11, and the distal end portion of the insertion portion 11 can be passed inside the annular shape portion (implementation). See FIG. 6 of Example 2).
As shown in FIG. 3, for example, the direction of the emission surface of the LED 22 a is shown in FIG. 2 so that the direction in which the illumination light emitted from the LED 22 a is emitted is an obliquely rearward inner direction on the optical axis O side of the objective lens 15. It may be changed. In this way, the visual field range on the short distance side by the objective lens 15 can be illuminated more effectively. Note that FIG. 3 shows an angle θ at which the illumination light emitted by the two LEDs 22a arranged opposite to each other in the diameter direction is emitted.

In this embodiment, as shown in FIG. 2 or FIG. 3, a plurality of LEDs 22 a are arranged along, for example, a rotationally symmetric circle on the optical axis O of the objective lens 15. The alignment means is formed so that the field of view by the objective lens 15 facing the rear side of the plurality of LEDs 22a can be efficiently illuminated by emitting illumination light from the plurality of LEDs 22a.
That is, when the living body 2 is illuminated from the back side by the LED unit 22 serving as an illuminating means, the transmitted light that has passed through the living body 2 is efficiently incident on the objective lens 15 as incident light that is imaged by the image sensor 18. So that they are aligned.
Further, the LED unit 22 can be moved in a direction parallel to the visual field direction, and as shown in FIG. 1, the living body 2 portion to be observed is disposed between the LED unit 22 and the objective lens 15 and observed with the transmitted light. The target can be observed efficiently.

The operation of the present embodiment having such a configuration will be described.
When observing the living body 2 to be observed, the operator moves the slide lever 25 to the front side, moves the illumination unit 3 to the front side of the transparent hood 14 as shown in FIG. The living body 2 is disposed between the LED unit 22 and the transparent hood 14 at the tip of the hood.
When the amount of force to move the slide lever 25 forward is reduced, the illumination unit 3 moves rearward due to the elastic force of the coil spring 24, and as shown in FIG. 1, between the LED unit 22 and the transparent hood 14. The living body 2 can be set in a sandwiched state.
As shown in FIG. 1, the living body 2 is sandwiched between the LED unit 22 and the transparent hood 14 to illuminate the living body 2 from the back side with illumination light from the LED unit 22, and the illuminated living body The transmitted light that has passed through 2 can be efficiently incident on the objective lens 15.

Since the LED 22a of the LED unit 22 includes a wavelength region that emits light on the longer wavelength side than the wavelength of 1200 nm, the transmission distance that passes through the living body 2 can be increased when irradiated with infrared light in that wavelength region.
FIG. 4A shows an example of an image captured by the image sensor 18 and displayed on the monitor 8 when the living body 2 is sandwiched as shown in FIG.
When the living body 2 is formed of, for example, adipose tissue and a blood vessel is running inside or on the LED unit 22 side, the distance through which the light is transmitted in the state of normal observation with light in the visible region is as follows. Get smaller.

For this reason, when observation is performed with light in the visible region, for example, as shown by a dotted line in FIG. 4B, the blood vessel 31 is blocked by the adipose tissue 32 and it is difficult to obtain a clear image of the blood vessel running. become.
In contrast, in the present embodiment, illumination is performed with light having a wavelength longer than 1200 nm, which has a large transmission distance with respect to a living tissue such as adipose tissue 32, and the imaging element 18 having sensitivity in the wavelength region is provided. It is used for imaging.
Therefore, when illuminated with this infrared light, for example, as shown in FIG. 4A, the adipose tissue 32 can be transmitted, and at the blood vessel 31 portion, the transmitted light absorbed by the blood portion therein is absorbed. Is incident on the objective lens 15 side. The optical image formed by the objective lens 15 is transmitted by the image guide 16 and is imaged by the imaging element 18 disposed at the imaging position via the imaging lens 17. Then, signal processing is performed by the signal processing circuit 28 of the CCU 7, and an image captured by the image sensor 18 is displayed on the monitor 8 as an endoscopic image by infrared light.

Therefore, according to the present embodiment, the traveling state of the blood vessel 31 can be observed as an easily distinguishable image with a large contrast difference. That is, an image having a contrast that passes through the adipose tissue 32 and becomes black due to absorption in the blood vessel 31 is obtained.
Further, in the present embodiment, the plurality of LEDs 22a constituting the LED unit 22 are aligned and disposed so as to face the observation field of view by the objective lens 15 constituting the imaging means. The transmitted light that has passed through the living body 2 is efficiently incident on the objective lens 15 side.
For this reason, the amount of incident light of the light transmitted through the living body 2 is increased in the objective lens 15 and an image having a good S / N is obtained.
Therefore, according to the present embodiment, infrared observation can be performed with good image quality.

Further, in this embodiment, as described above, since imaging is performed with the transmitted light that has passed through the living body 2, the blood vessel 31 on the deeper side of the living body 2 from the objective lens 15 side than in the case of imaging with reflected light. It is possible to obtain an image of the running state with better S / N.
That is, when imaging is performed with reflected light, it is necessary to capture the return light reflected from the objective lens 15 side at the site on the deep layer side of the living body 2, and in this case, the light reflected on the surface layer side. As compared with the above, the optical path length in the living body 2 becomes longer, and the attenuation in the living body 2 becomes larger accordingly. On the other hand, when imaging the transmitted light of the living body 2, the optical path length in the living body 2 is almost the same on the deep layer side and the surface layer side of the living body 2. The phenomenon that the intensity of the reflected light becomes smaller than that in the case of from the shallow layer side can be reduced. For this reason, it is possible to obtain image information relating to blood vessel running, etc., particularly on the deep layer side, with a good S / N.

Moreover, according to the present Example, the temperature of the biological body 2 can be raised a little by irradiating the illumination light of LED22a by the LED unit 22 in contact with the biological body 2 (in other words, from a short distance).
FIG. 5 shows spectral transmittance characteristics obtained by measuring the transmittance of fat before and after irradiation with a dryer, for example. More specifically, the measurement result of the transmittance of fat before and after irradiation with hot air for 10 seconds (fat) with a 1200 W dryer at a distance of 10 cm from the fat to be measured is shown.
As shown in FIG. 5, the transmittance of adipose tissue increases after heat irradiation. Therefore, even when irradiating the living body 2 with light having a wavelength longer than 1200 nm by the LED 22a and observing the living body 2, the irradiation is performed at a short distance so as to be in contact with the living body 2 in particular. In addition, the transmittance in the fat tissue portion can be increased. For this reason, according to the present Example, it becomes possible to observe the blood vessel 31 in a more contrasted state.

Next, a second embodiment of the present invention will be described with reference to FIGS. 6 shows the configuration of the endoscope according to the second embodiment of the present invention, FIG. 7 shows an enlarged part of the front end side of FIG. 6, and FIG. 8 shows the periphery of the power supply switching circuit on the rear end side of FIG. The structure of a part is shown.
In the present embodiment, illumination is performed from the back side of the living body 2 as in the first embodiment, and in addition to the first illumination unit that performs illumination so that the transmitted light of the living body 2 is incident on the objective lens 15, the objective lens 15 is provided with second illumination means for illuminating the living body 2 on the front side of the visual field so that the reflected light is incident on the objective lens 15.
An endoscope 6B according to the second embodiment includes an endoscope body 4B and an infrared camera 5B. The endoscope body 4B includes a front LED unit 41 that performs front illumination and a rear LED unit 42 that performs rear illumination instead of the illumination unit 3 that illuminates the rear side of the endoscope body 4 of the first embodiment. 3B is provided.

That is, the annular illumination unit 3B provided at the tip of the support rod 21a of the cylindrical slide portion 21 is provided with a front LED unit 41 that performs front side illumination on the front side portion thereof, and on the rear side. Is provided with a rear LED unit 42 for performing rear side illumination.
In addition, the infrared camera 5B is provided with a slide detection switch 43 as movement detection means for detecting movement of the illumination unit 3B by sliding in the infrared camera 5 of the first embodiment. In addition, a power supply switching circuit 44 that switches supply of LED power according to a slide detection result by the slide detection switch 43 is provided.
That is, as shown in FIG. 6, in a state where the rear end of the slide portion 21 is disposed at the rearmost side, the rear end surface presses the slide detection switch 43 provided inside the infrared camera 5B, and this slide detection is performed. The switch 43 is turned on.

In this state, as shown in FIG. 7 showing the front end side of FIG. 6 in an enlarged manner, LED power is supplied to the front LED unit 41 that performs front illumination, and the LED 41a that constitutes the front LED unit 41 is caused to emit light (light on). Further, when the slide part 21 is moved to the front side from the state of FIG. 6 and the slide detection switch 43 is turned OFF, the power supply switching circuit 44 supplies the LED power to the rear LED unit 42 to perform the rear illumination. To do.
The configuration of the periphery of the power supply switching circuit 44 that switches the supply of the LED power supply in accordance with the detection signal of the slide detection switch 43 is shown in FIG.
The detection signal of the slide detection switch 43 is input to the switch detection circuit 45. The switch detection circuit 45 controls the contact a of the changeover switch 46 to be ON when the slide detection switch 43 is ON. LED power from the power supply circuit 29 is supplied to the front LED unit 41.

The switch detection circuit 45 controls the contact b of the changeover switch 46 to be ON when the slide detection switch 43 is OFF, and supplies the LED power from the LED power supply circuit 29 to the rear LED unit 42.
In this embodiment, the signal lines 47a and 47b connected to the front LED unit 41 and the rear LED unit 42 are connected to the slide contacts 48a and 48b provided inside the slide portion 21 and the contacts 49a and 498b of the infrared camera 5B. Then, it is connected to the contacts a and b of the changeover switch 46.
Specifically, as shown in FIG. 8, a projecting piece extends from the infrared camera 5B side to the front side, and contacts 49a and 49b are provided on the upper and lower surfaces thereof, and slides in contact with the projecting piece. Slide contacts 48a and 48b are provided on the upper inner surface and lower inner surface of the moving slide portion 21, respectively.

In the first embodiment, the illuminating means is provided so as to be aligned so as to emit the illumination light to the rear objective lens 15 side, whereas in the present embodiment, the illumination means is further on the front side in the visual field direction of the objective lens 15. Positioning is provided so as to emit illumination light. Moreover, when the illumination unit 3B is moved, a switching unit that detects the movement and switches between the front illumination and the rear illumination is also provided.
Other configurations are the same as those of the first embodiment. Next, the operation of this embodiment will be described.
In this embodiment having such a configuration, the front LED unit 41 and the like as front illumination means for illuminating the front side are further provided as compared with the case of the first embodiment. When the 3B slide portion 21 is set in the retracted state on the rear side, the front side of the visual field of the objective lens 15 can be illuminated by the front LED unit 41. Then, the front side of the visual field can be observed with infrared rays.

Further, when the living body 2 is to be observed with transmitted light as in the first embodiment, the slide detection switch 43 is changed from the ON state to the OFF state by moving the slide portion 21 forward.
When the slide detection switch 43 changes from ON to OFF, the LED power supply supplied from the LED power supply circuit 29 by the power supply switching circuit 44 is switched. Then, the illumination state by the front LED unit 41 is switched to the illumination state by the rear LED unit 42.
Then, infrared observation with transmitted light can be performed in the same manner as in Example 1.
Therefore, according to the present embodiment, in addition to having the same effects as those of the first embodiment, infrared observation by front illumination can be further performed. Further, since the movement of the slide portion 21 is detected and the illumination mode between the front illumination and the rear illumination is automatically switched in accordance with the movement, it becomes easy to use.
Therefore, according to the present embodiment, the observation function is improved and the usability is further improved.

Next, a third embodiment of the present invention will be described with reference to FIGS. FIG. 9 shows the configuration of the endoscope and the light source device according to the third embodiment of the present invention, and FIG. 10 shows the configuration of the power supply switching circuit peripheral portion on the rear end side of the endoscope. In the second embodiment, the front LED unit 41 that illuminates the front side is provided, but in this embodiment, this function is realized by another configuration.
The infrared observation system of the present embodiment includes an endoscope 6C shown in FIG. 9 instead of the endoscope 6B of the second embodiment, and a light source device 51 that supplies illumination light in the infrared region to the endoscope 6C. It has.
The endoscope 6C in the present embodiment includes an endoscope main body 4C and an infrared camera 5C fixed to the endoscope main body 4C. The endoscope main body 4C is a front LED in the endoscope main body 4B of FIG. The unit 41 is not provided, and the lighting unit 3C having the rear LED unit 42 is provided.

  That is, the rear LED unit 42 has substantially the same configuration as the LED unit 22 of the first embodiment.

In addition, in the endoscope body 4C, a light guide 52 that transmits illumination light is inserted into the insertion portion 11, and the light guide 52 is connected to a base portion provided near the rear end of the insertion portion 11. Is detachably connected to the light source device 51 through the light guide cable 53.
The endoscope main body 4C does not have the signal line 47a because the front LED unit 41 is not provided as described above, and is provided only on the side of the signal line 47b connected to the rear LED unit 42. As shown in FIG. 10, the signal line 47b is connected to the changeover switch 46 'of the power supply changeover circuit 44' through the slide contact 48b and the contact 49b on the infrared camera 5C side.

The power supply switching circuit 44 'has a switch detection circuit 45' that detects a switch signal of the slide detection switch 43, and the switch detection circuit 45 'turns ON / OFF the contact b of the changeover switch 46' by the output signal. At the same time, a control signal is sent to the lamp lighting control circuit 55 of the light source device 51.
The light source device 51 includes, for example, a halogen lamp 56 that generates light having a wavelength longer than a wavelength of 1200 nm in the visible region to the infrared region, an infrared transmission filter 57 disposed on the illumination light path of the halogen lamp 56, and the like. And a condensing lens 58 that condenses light in the infrared region having a wavelength longer than 1200 nm transmitted through the infrared transmission filter 57. The light in the infrared region collected by the condenser lens 58 is supplied to the light guide 52 in the endoscope body 4C through the light guide of the light guide cable 53.

The halogen lamp 56 has continuous light emission characteristics from the visible region to a wavelength band exceeding, for example, 3000 nm. In addition to the halogen lamp 56, a mercury lamp or the like that generates light having a longer wavelength than the wavelength of at least 1200 nm may be employed.
The halogen lamp 56 is controlled to emit (turn on) / turn off by the lamp lighting control circuit 55. The lamp lighting control circuit 55 controls lighting / extinguishing of the halogen lamp 56 by a control signal from the switch detection circuit 45 'of the power supply switching circuit 44'.
Specifically, when the slide detection switch 43 is ON, the switch detection circuit 45 'turns off the contact b as shown in FIG. 10 and causes the lamp lighting control circuit 55 to turn on the halogen lamp 56. Send.

When the slide detection switch 43 is OFF, the switch detection circuit 45 ′ sends a control signal for turning on the contact b from the state shown in FIG. 10 and turning off the halogen lamp 56 to the lamp lighting control circuit 55. Other configurations are the same as those of the second embodiment. Next, the operation of this embodiment will be described.
In the present embodiment having such a configuration, in the state where the slide portion 21 is moved to the rearmost side as shown in FIG. 9, instead of causing the front LED unit 41 in the second embodiment to emit light, the infrared region by the light source device 51 is used. Light is transmitted through the light guide 52 and emitted from the distal end surface through the transparent hood 14 to illuminate the front side of the field of view of the objective lens 15.
In addition, when the living body 2 is to be observed with infrared rays using transmitted light, the slide portion 21 of the illumination unit 3C is moved forward.

When the slide unit 21 is moved forward, the slide detection switch 43 changes from the ON state to the OFF state. Due to this change, the halogen lamp 56 of the light source device 51 is turned off by the switching operation of the power supply switching circuit 44 ', and the LED is turned on. The LED power of the power supply circuit 29 is supplied to the rear LED unit 42 and switched to a state in which the rear side is illuminated.
As in Example 1 or Example 2, infrared observation using transmitted light can be performed.
Therefore, according to the present embodiment, the configuration of the front illumination means is different from that in the second embodiment, but the same effect as in the second embodiment is obtained.
That is, this embodiment has the same effect as that of the first embodiment, and can also perform infrared observation by front illumination.
In addition, since the present embodiment is configured to be easily applied to an existing optical endoscope, it can be manufactured at a low cost.

Next, a fourth embodiment of the present invention will be described with reference to FIGS. FIG. 11 shows an infrared observation system 1D according to the fourth embodiment of the present invention.
An infrared observation system 1D of Example 4 shown in FIG. 11 includes an optical endoscope 4D to which an illumination unit 3D is detachably attached, and an infrared camera 5D to be attached to the endoscope 4D. The camera-equipped endoscope 6D, the CCU 7D, the light source device 51D, and the monitor 8 are included. In the endoscope 4D, a transparent hood 14 is attached to the distal end portion 13 of the insertion portion 11, the proximal end side of the insertion portion 11 is enlarged in diameter, and a grasping portion (or operation portion) 61 that an operator grasps is provided. The infrared camera 5D is detachably connected to the eyepiece 62 at the rear end of the grip 61.

A cylindrical unit attachment portion 63 provided on the rear end side of the illumination unit 3D is detachably attached to the grip portion 61 by a fixing screw 64, and a base of the slide portion 21 is provided inside the unit attachment portion 63. The end side is slidably held using a coil spring 24.
This endoscope 4D is provided with an objective lens 15, an image guide 16, and a light guide 52 as in the third embodiment. The rear end of the image guide 16 is disposed in the vicinity of the eyepiece 62, and the surgeon can observe the optical image transmitted to the rear end surface of the image guide 16 through the eyepiece 65.
Further, in the infrared camera 5D attached to the eyepiece 62, the imaging lens 17 is disposed so as to face the eyepiece 65, and normal light is applied to the imaging position by the eyepiece 65 and the imaging lens 17. An imaging element 68 for imaging is arranged.

A dichroic mirror 66 that reflects, for example, light in the infrared region and transmits light in the visible light region is disposed between the imaging lens 17 and the image sensor 68 for normal light imaging. An imaging element 18 for infrared imaging is disposed at the imaging position reflected by 66.
The dichroic mirror 66 reflects the light in the infrared region, but may have a characteristic of reflecting the light in the infrared region of 1200 nm or more. In this case, a filter that cuts off part of the light in the infrared region incident on the image sensor 68 for normal light imaging may be disposed.
The image sensor 18 for infrared imaging and the image sensor 68 for normal light imaging have the same number of pixels, for example, and are driven simultaneously by an image sensor driving signal from the image sensor driving circuit 27 provided in the CCU 7D, for example. Is done.

Signals photoelectrically converted by the imaging element 18 for infrared imaging and the imaging element 68 for normal light imaging are input to the signal processing circuit 28D. This signal processing circuit 28D has a signal processing function for two input signals, generates a video signal from each of the input signals, further mixes them by an internal mixing circuit, outputs them to the monitor 8, and outputs an infrared image 8a and a normal signal. The image 8b is displayed.
In the illumination unit 3D, for example, a rear LED unit 42 is attached to the tip of a support bar extending from the tip of the slide portion 21.
As shown in FIG. 12, the signal line 47b connected to the rear LED unit 42 is provided on the side of the unit mounting portion 63 that is in sliding contact with the slide contact 69a provided on the end surface protruding in an L shape at the rear end of the slide portion 21. Connected to the contact 69b. The contact 69b is connected to a switch 70 for ON / OFF, and a signal line 67 extending from a terminal connected to the switch 70 is connected to the LED power supply circuit 29 of the CCU 7D.

Note that the configuration is not limited to the contact structure shown in FIG. Further, a simplified configuration may be adopted by forming a curl as in the first embodiment.
In the present embodiment, an existing rigid endoscope can be adopted as the endoscope 4D. In this embodiment, in addition to the image sensor 18 for infrared imaging, an image sensor 68 for normal imaging is provided in the infrared camera 5D.
Then, both of the imaging elements 18 and 68 can obtain (observable) an infrared image 8a imaged with infrared light and a normal image 8b imaged with light in the visible region (normal light). Other configurations are the same as those of the third embodiment. Next, the operation of this embodiment will be described.
As shown in FIG. 11, in the state where the illumination unit 3D is moved to the rearmost side, the distal end of the illumination unit 3D is arranged on the outer peripheral surface behind the distal end surface of the endoscope 4D (the distal end surface of the transparent hood 14). (Evacuated) state.

In this state, the endoscope 4D is in a state close to that of a normal rigid endoscope, and the insertion portion 11 (with the slide portion 21 provided on the outer peripheral surface) is inserted into the body cavity via a trocar (not shown) or the like. be able to.
The light source device 51 supplies illumination light from the visible region to the infrared region (having a longer wavelength longer than 1200 nm) to the light guide 52, and becomes an observation target such as an organ in a body cavity via the light guide 52. Illumination light is irradiated to the living body part.
The light reflected by the illuminated body part is incident on the infrared camera 5D side through the endoscope 4D, and the light in the infrared region is reflected by the dichroic mirror 66 and imaged on the image sensor 18 to be visible region. Is transmitted through the dichroic mirror 66 and focused on the image sensor 68.

The signals imaged by both the image sensors 18 and 68 are processed by the signal processing circuit 28D, and the infrared image 8a and the normal image 8b are displayed on the monitor 8 simultaneously, for example.
Therefore, the surgeon can obtain the infrared image 8a and the normal image 8b by the light reflected by the living body part irradiated with the illumination light.
On the other hand, when performing infrared observation using transmitted light, the user operates the switch 70 to supply the LED power from the LED power supply circuit 29 to the rear LED unit 42 and turn on the LED 42a.
Further, for example, as in the case of the third embodiment, the slide portion 21 of the illumination unit 3D is moved to the front side, and the living body part is sandwiched between the rear LED unit 42 and the transparent hood 14 at the tip thereof. Infrared observation with transmitted light can be performed.
Also in this case, the normal image 8b by reflected light can be obtained.

According to the present embodiment, it is possible to obtain a normal image in the visible region by reflected light, so that it can be used for normal observation other than the case of performing infrared observation. Further, according to the present embodiment, since a normal optical endoscope can be used, it can be realized at low cost.
Moreover, since the illumination unit 3D is configured to be detachable, the illumination unit 3D can be removed and used for infrared observation and normal observation using reflected light when it is not necessary. Note that embodiments configured by partially combining the above-described embodiments also belong to the present invention.

[Appendix]
1. 2. The illumination unit according to claim 1, wherein the illumination unit illuminates the living body from the back side of the living body on the front side of the visual field of the objective optical system, and transmits the illumination light so that the transmitted light transmitted through the living body is incident on the objective optical system. appear.
2. In Claim 1, The said positioning means has a moving means to move the said illumination means.
3. In Claim 4, the said positioning means has a moving means to move the said illumination means.
4). In Supplementary Note 3, there is provided switching means for switching the illumination operation between the first illumination means and the second illumination means by moving the moving means.
5. In Claim 1, it has an imaging means in a visible region further.

  By irradiating the living body with light in the infrared region longer than the wavelength of 1200 nm, it is possible to obtain image information corresponding to the state of blood vessel traveling on the deep side of the living body, and the field of view range by the objective optical system constituting the imaging means Since an alignment mechanism is provided so that illumination can be performed effectively, an infrared image with good image quality can be obtained.

1 is an overall configuration diagram of an infrared observation system according to a first embodiment of the present invention. The perspective view which shows the structure of the illumination unit etc. of the front end side of the insertion part of an endoscope. The block diagram which shows the structure of the modification which changed the illumination direction in an LED unit. Explanatory drawing which shows the typical image example obtained by a present Example compared with the case of a visible region. The measured transmittance | permeability characteristic figure which shows that the transmittance | permeability of fat can be enlarged by heat irradiation. The block diagram of the endoscope in Example 2 of this invention. The block diagram which expands and shows a part of the front end side of FIG. The figure which shows the structure of the power supply switching circuit periphery part of the rear end side of FIG. The block diagram of the endoscope and light source device in Example 3 of this invention. The figure which shows the structure of the power supply switching circuit periphery part of the rear end side of an endoscope. FIG. 6 is an overall configuration diagram of an infrared observation system according to a fourth embodiment of the present invention. Sectional drawing which shows the contact structure part of the rear-end side of an illumination unit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Infrared observation system 2 ... Living body 3 ... Illumination unit 4 ... Endoscope body 5 ... Infrared camera 6 ... Endoscope 7 ... CCU
DESCRIPTION OF SYMBOLS 8 ... Monitor 11 ... Insertion part 13 ... Tip part 14 ... Transparent hood 16 ... Image guide 18 ... Image pick-up element 21 ... Slide part 22 ... LED unit 23 ... Tube part 24 ... Coil spring 25 ... Slide lever 27 ... Image pick-up element drive circuit 29 ... LED power supply circuit 28 ... Signal processing circuit

Claims (5)

Illuminating means for irradiating a living body to be observed with illumination light in an infrared region longer than a wavelength of at least 1200 nm;
An imaging means provided with an imaging element that is arranged at an imaging position of an objective optical system that connects optical images or an imaging position that transmits an optical image by the objective optical system and has sensitivity in an infrared region longer than a wavelength of 1200 nm;
Signal processing means for performing signal processing on an imaging signal by the imaging means;
An infrared observation system comprising: an alignment unit that aligns the illumination unit relative to the objective optical system.   The said illuminating means is opposingly arranged along the visual field direction of the said objective optical system, and the said alignment means is formed so that it can slide to the direction parallel to the said visual field direction, It is characterized by the above-mentioned. Infrared observation system.   2. The living body can be arranged between the objective optical system and the illuminating means arranged opposite to the visual field direction of the objective optical system. Infrared observation system.   The illuminating means illuminates a living body opposite to the visual field direction of the objective optical system, and generates first illuminating light for causing reflected light from the living body to enter the objective optical system; and the objective Second illumination means for illuminating the living body from the back side opposite to the visual field direction of the optical system and generating illumination light that causes the transmitted light that has passed through the living body to enter the objective optical system. The infrared observation system according to claim 1, wherein   The infrared observation system according to claim 4, further comprising a switching unit that switches an illumination operation between the first illumination unit and the second illumination unit.

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