JPH0690363B2 - Endoscope device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an endoscope apparatus having a projecting illumination light emitting portion whose outer periphery is shielded.

[Prior Art] In recent years, by inserting an elongated insertion part, an endoscope that can observe the inside of a body cavity without performing an incision and can perform treatment with a treatment tool is widely used. became.

The conventional endoscope observation is performed by irradiating the observation site in the living body with the light emitted from the light guide at the distal end of the endoscope, forming an image of the reflected light with a lens, and using the image transmission means. It was

As the light for illumination, not only visible light but also infrared light, ultraviolet light, etc. have been used.

In particular, infrared light is often used when observing the state of a submucosal tumor or blood vessel in a living body because it has excellent transmission characteristics in the living body. However, even if it is said that infrared light has good transmission characteristics into living tissue, the proportion of light reflected on the tissue surface is large compared to the amount of light that penetrates into tissue, so conventional illumination methods Only surface information such as the uneven shape of the surface and the difference in color tone was obtained. Even if the subsurface blood vessel running state could be identified, it was very unclear and was not at a level practically used for diagnosis.

[Problems to be Solved by the Invention] In conventional observations under the surface of a tissue of a living body, only the reflected light on the surface was large, and information about the surface of the tissue was hardly obtained. Therefore, it is easy to observe and diagnose cancers that are deformed on the surface of the tissue or change in color tone by conventional methods, but early cancers that do not appear on the surface, submucosal tumors, etc. There was a problem that it was difficult to discover.

The one disclosed in Japanese Utility Model Laid-Open No. 58-168711 is one in which the front part of the emission end of the illumination light guide is projected to prevent the observation window from adhering to the inner wall of the body cavity and blocking the view. Therefore, it is possible to illuminate a wide range and does not solve the above problems. Further, since the protruding portion is transparent, it is difficult to completely prevent the light emitted from the side peripheral side from being reflected on the surface of the body cavity even if it is pressed against the inner wall surface of the body cavity. In addition, since the protrusion has a curved shape, it is difficult to make the whole closely adhere. Further, even if it can be emitted to the body cavity side, normal illumination light is assumed, so it is greatly attenuated in the body cavity, and it is not possible to observe the deep side inside the tissue surface due to observation with visible light. .

The present invention has been made in view of the above points, and provides an endoscope apparatus that allows illumination light to be transmitted through a tissue and prevents reflection on the tissue surface to allow easy observation / diagnosis below the tissue surface. The purpose is to provide.

[Means and Actions for Solving Problems] In the present invention, the light guide emission end face portion is provided at a position projecting from the observation lens surface at the tip of the insertion portion, and the portion other than the light guide emission end face portion is covered with an optical shading member. By closely contacting the emitting end face with the tissue surface, the illumination light is efficiently emitted into the tissue so that the inside of the tissue can be observed.

EXAMPLES The present invention will be specifically described below with reference to the drawings.

1 to 4 relate to a first embodiment of the present invention.
The figure shows an enlarged view of the tip side of the first embodiment, and FIG.
FIG. 3 shows a filter inserted in an illumination optical path, and FIG. 4 shows an example of a usage state.

As shown in FIG. 2, the endoscope apparatus 1 according to the first embodiment has an endoscope 3 having an elongated insertion portion 2 that can be inserted into a body cavity, and a light guide provided in the endoscope 3. Cable 4
It is composed of a light source device 5 for supplying illumination light to the TV and a television monitor 6 for displaying a picked-up image from an electric signal picked up by the endoscope 3.

A light guide fiber (bundle) 8 is inserted into an elongated insertion portion 2 of the endoscope 3, and the light guide fiber 8 is a flexible light protruding from an operation portion 9 having a large diameter or a wide width. Through the inside of the guide cable 4, the connector 11 provided at the end of the light guide cable 4 is connected to the light source device 5
By mounting it on (the connector receiver), the end face (incident end face) of the connector 11 is irradiated with the illumination light of the illumination lamp 12 that emits light in a wavelength range including infrared light.

The illuminating light applied to the incident end face of the light guide fiber 8 passes through the light guide cable 4 and the light guide fiber 8 in the insertion part 2, and then the end face of the tip illumination part 13 protruding from the tip of the insertion part 2, that is, the emission end face. The emitted light is diffused by the illumination lens 14 formed of a concave lens or the like so that it can be irradiated to the front of the lens 14. still,
The illuminating light of the illuminating lamp 12 is cut with infrared light by a visible light transmitting filter 15 that can be projected and retracted on the optical path between the lamp 12 and the incident end of the light guide fiber 8 to illuminate only the visible light. Alternatively, it is possible to cut visible light through an infrared light transmission filter 16 and illuminate only with infrared light. The filters 15 and 16 can be arranged, for example, as shown in FIG. 3, in a fan-shaped portion of the rotary filter 17, and can be arranged to cover the light flux by rotating the rotary filter 17. Reference numeral 18 is a transparent portion, which can be set to a state in which both infrared light and visible light can pass through.

By the way, an image pickup lens 19 is arranged on the distal end surface of the insertion portion 2, and a solid-state image pickup element 21 is arranged on the focal plane of the lens 19 so that the image pickup surface faces. Then, the optical image formed on the image pickup surface is photoelectrically converted and transmitted by the cable 22 inserted through the insertion portion 2. This cable 22 is further inserted through the light guide cable 4, and the connector 11
Is connected to the cable 23 in the light source device 5. The video signal is input to the video processing circuit 24 by the cable 23 and is displayed on the television monitor 6 as a composite video signal of the NTSC system or the like.

The solid-state image sensor 21 has a red color on the front surface of its imaging chip.
Filters that pass green, blue, that is, R, G, and B wavelengths as well as infrared light (IR), that is, R + IR, G + IR, B + IR
A color filter 25 in which these filters are arranged in a checkerboard pattern or a mosaic pattern is arranged.

By the way, the tip illumination unit 13 which is the main part of the first embodiment,
The outer peripheral side surfaces other than the emission end surface are covered with an outer cylinder 26 made of a metal tube or the like that blocks infrared light and visible light. Therefore, the illumination light does not leak to the surroundings from the outer peripheral side surface. The distal end side of the light guide fiber 8 inserted through the insertion portion 2 is filled in the outer cylinder 26. The outer cylinder 26
The projecting length L due to is not less than the minimum focal length observable by the lens 19.

An example of use of the first embodiment thus configured will be described below.

The connector 11 of the light guide cable 4 of the endoscope 3 is attached to the light source device 5, and the insertion section 2 is inserted into the body cavity from the oral cavity or the like. For example, as shown in FIG. 1 or 2, the tip of the insertion section 2 is inserted. The surface is set near the tissue 27 of the observation target portion. Then, in this state, the illumination light is irradiated toward the surface of the tissue 27,
The surface of the tissue 27 can be observed by using the imaging means including the lens 19 and the solid-state imaging device 21. In this case, for example, as shown in FIG. 2, if the illumination light of the illumination lamp 12 is observed under white illumination in which the infrared light is cut by the visible light transmission filter 15, it is possible to observe an ordinary endoscope. It can be performed in the same manner as in.

On the other hand, when it is desired to observe the state under the tissue, the distal end side of the insertion portion is brought close to the surface of the tissue 27, and the distal end surface of the protruding outer cylinder 26 is pressed against the surface of the tissue 27 to remove the lens as shown in FIG. The 14th surface is brought into close contact with the surface of the tissue 27.

When this state is set, the filter in the light source device 5 is switched to the infrared light transmitting filter 16 to illuminate the inside of the tissue 27 with infrared light. Since this infrared light is less attenuated in the living tissue 27 than visible light, it can be irradiated to a deeper side. Then, as shown in FIG. 4, when there is a submucosal tumor 28 or a blood vessel 29 portion that is hyperemic inside the surface of the tissue 27, the reflected light from that portion is imaged by the lens 19 on the image pickup surface of the solid-state image pickup device 21. Moreover, since blood has a high absorption rate of infrared light, there is little reflected light at that portion and a blood image is formed as a shadow image, and the output of this solid-state image pickup device 21 can be displayed on the television monitor 6 via the video processing circuit 24.
In this way, when the emission end face of the tip illumination unit 13 is closely attached,
Since the outer peripheral surface other than the front end surface of the projecting tip illuminating section 13 is formed by the outer cylinder 26 made of a light shielding member, it is not emitted to the inside of the tissue 27 in the conventional example, but reflected on the surface of the tissue 27 and imaged. It is possible to reliably prevent light leakage. Therefore, according to the first embodiment, it is possible to form an image of only the light reflected inside the tissue, which is almost impossible in the conventional example, so that an extremely clear subsurface image can be obtained. It is possible to realize a very effective endoscopic device.

5 and 7 show the arrangement shape of the distal end of the endoscope in the second embodiment of the present invention.

An imaging lens 19, a forceps channel 32, and a tip illumination section 13 are arranged at the tip 31 of the insertion section of the endoscope 3. In this embodiment, as compared with the image pickup system including the lens 19 and the solid-state image pickup device 21, the distal end illumination section 13 has a central portion with respect to one side of the outer circumference of the visual field 33 of the endoscope 3, as shown in FIG. It is arranged at a position deviating from the above so that a part of the tip illumination unit 13 can be seen. That is, in FIG. 5, the viewing angle of the image pickup system viewed from the direction of the line AA ′ is as shown in FIG. 7, and a part of the tip illumination unit 13 is within the field of view.

The operation of the second embodiment thus arranged will be described below.

When the endoscope 3 is inserted into the body and various parts are observed, the endoscope 3 is rotated around the axial direction of the insertion portion 2,
In addition, the bending portion formed near the distal end of the insertion portion 2 is often bent for observation. When such an operation is performed, if there is no marker indicating the position in the visual field 33, the observing direction cannot be known, which is inconvenient, but according to this embodiment, the tip illumination unit 13 is in the visual field 33. Since a part of the peripheral part deviates from the center, it is possible to easily observe and diagnose while observing the direction of observation.

FIG. 8 shows an endoscope 41 according to the third embodiment of the present invention.

In this embodiment, the protruding length of the tip illumination unit 13 is variable.

The operation section 42 of the endoscope 41 is provided with, for example, an operation lever 43 that can slide along the upper surface of the operation section.
By moving, the tip illumination part 13 can be projected as shown in FIG. 8 (a), or the projection length can be made zero as shown in FIG. 8 (b).

The operation lever 43 can move in a channel tube 44 formed in the insertion portion 2 as shown in FIG. 9, and is connected to a proximal end portion of a tube 45 made of Teflon or the like covering the light guide fiber 8. ing.

The light guide fiber 8 inserted through the channel tube 44 of the insertion section 2 is covered with a highly flexible silicon tube 46 in the operation section 42. That is, in the channel in the insertion portion 2, the light guide fiber 8 is covered with the Teflon tube 45 having a small friction resistance and easy to slide so as to be easily moved, and the bent portion of the operation portion 42 is made of the silicon tube 46. Incidentally, O-rings 47, 47 are provided near both ends of the channel tube 44.

In the third embodiment configured in this way, when performing the same illumination as the conventional one, the operation lever 43 is pulled toward the hand side to
As shown in FIG. 3B, the protrusion amount of the tip illumination unit 13 is set to zero. On the other hand, when observing and diagnosing the subsurface of the tissue 27, as shown in FIG. 8 (a) or FIG.
Sent to the front side, project the tip illumination unit 13 forward,
The front surface is closely attached to the surface of the observation site for observation.

In this case, if you want to magnify and observe under the tissue surface,
The projection length of the tip illumination unit 13 may be set to be short, while it can be realized by increasing the projection length when observing a wide range. By changing the protrusion length in this way, it is possible to perform observation under conditions suitable for observation. Further, when the insertion section 2 is inserted into the body cavity, even when the outer cylinder 26 may damage the inner wall surface of the body cavity when the tip illumination section 13 is projected, the insertion operation should be performed in the retracted state. It can also be done and safety can be ensured.

In the third embodiment, the light guide fiber 8
The channel through which the light guide fiber 8 is provided may be used, but a normal treatment tool channel may also be used.

In the above-described embodiment, the visible light imaging means uses the solid-state imaging device provided with the color filter 25 under white illumination, but the present invention is not limited to this, and a frame sequential illumination system is used. In addition, a monochrome solid-state image sensor without the color filter 25 may be used. In this case, for example,
In addition to red, green, and blue, infrared light (that is, R
+ IR, G + IR, B + IR), a rotary filter 51 provided with a fan-shaped filter 51R ', a filter 51G', and a filter 51B 'is provided between the lamp 12 and the incident end face of the light guide fiber 8, and a motor (not shown) is provided. It can be driven by rotation.

The outer cylinder 26 is not limited to a light-shielding member made of metal, and any non-metal member such as resin may be used as long as it shields visible light and infrared light. Further, even when the outer cylinder 26 is formed of a light-transmissive member, a light-shielding material may be applied to form a light-shielding member. The protruding outer cylinder 26 is not limited to a hard one, but may be a flexible one.

Further, although the present invention can be applied to a side-view endoscope,
A light guide fiber may be inserted into the treatment tool channel of a side-viewing endoscope so that it can be projected and retracted.

[Effects of the Invention] As described above, according to the present invention, the illumination light emitting portion that protrudes toward the distal end side of the insertion portion of the endoscope from the surface of the observation window and has the side outer surface shielded by the light shielding member. Since it is provided, it is possible to prevent the reflected light on the tissue surface from entering by adhering it to the tissue surface and observe the state inside the tissue surface.

[Brief description of drawings]

1 to 4 relate to a first embodiment of the present invention.
FIG. 4 is a side view showing the distal end side of the insertion portion in the first embodiment, FIG. 2 is a configuration diagram showing the overall configuration of the first embodiment, FIG. 3 is an explanatory diagram showing a filter, and FIG. FIG. 5 is a front view showing the distal end surface of the insertion portion in the second embodiment of the present invention, FIG. 6 is an explanatory view showing the visual field in the second embodiment, and FIG. 7 is A- in FIG. FIG. 8 is an explanatory view showing the field of view of the imaging system from the direction of the line A ′, FIG. 8 is a side view showing the endoscope in the third embodiment of the present invention, and FIG. 9 is a movable mechanism of the light guide fiber in the third embodiment. An explanatory view showing an outline of
FIG. 10 is a perspective view showing a peripheral portion of the rotary filter in the case of performing frame sequential illumination. DESCRIPTION OF SYMBOLS 1 ... Endoscope device, 2 ... Insertion part 3 ... Endoscope 4 ... Light guide cable 5 ... Light source device, 6 ... TV monitor 8 ... Light guide fiber 13 ... Tip illumination part, 14 ... Illumination lens 21 ... Imaging Lens, 21 ... Solid-state image sensor 25 ... Outer cylinder, 27 ... Tissue

Claims (2)

[Claims] 1. An endoscope apparatus provided with an illumination light emitting section for emitting illumination light and an observation window having a lens system for image pickup, wherein the illumination light emitting section is projected in the observation direction from the observation window. An endoscope apparatus characterized in that an outer periphery of an emission part other than the emission end face is shielded by a light shielding member. 2. The endoscope apparatus according to claim 1, wherein the light shielding member is a metal, a synthetic resin, or a paint that shields visible light and infrared light.