JPS63234939A - Endoscope - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) This invention relates to an endoscope that provides fi images of internal organs of the human body, etc.
It is designed to image fluorescence from internal organs, etc., with high resolution.

(Prior art) When imaging and inspecting internal organs of the human body, it is useful to irradiate excitation light such as ultraviolet rays and observe the fluorescence image emitted from the cells in order to identify the affected area. This is well known medically.

Examples of conventional endoscopes that capture such fluorescent images include the following. That is, a light guide for guiding excitation light from a light source into the body and an optical fiber for transmitting an image for guiding a fluorescent image obtained from the internal fission of the subject to the outside are bundled together and placed inside the body. A cable for insertion is constructed, and a filter for cutting excitation light and a TV camera are provided at the eyepiece part of the optical fiber for image transmission. The TV camera is connected to a CRT monitor via a suitable amplifier, frame memory, etc.

Then, when the subject is irradiated with excitation light, fluorescence fp! of a wavelength different from the wavelength of the excitation light emitted from the cell!
Excitation light reflected from the subject is guided out of the body via an image transmission optical fiber.

Among these, the excitation light is cut by a filter, and only the fluorescence image is formed on a TV camera to form an m image. Next, the image signal output from the TV camera is appropriately amplified, and then passed through a frame memory or the like and displayed as a fluorescent image on the CRT Tanabata screen.

(Problems to be Solved by the Invention) In conventional endoscopes, image transmission optical fibers for guiding fluorescent images from a subject to the outside of the body are arranged in parallel to a light guide, and filters for cutting off excitation light and Since TV cameras were arranged in the eyepiece of an optical fiber for image transmission to convey fluorescent images, the cable was thicker due to the installation valve of the optical fiber for image transmission, making it difficult to insert it into the body. There is a problem that the subject may be in pain when the test is performed, and the resolution is reduced by 1a.

This invention was made based on the above-mentioned circumstances, and it is an object of the present invention to provide an endoscope that can make the cable inserted into the body thinner and improve the decomposition fil.

[Structure of the Invention] (Means for Solving the Problems) In order to solve the above problems, the present invention includes a light source that emits excitation light to excite a subject and obtain a fluorescent image, and a light source that is attached to the distal end of a scope. The object of the present invention is to include an image pickup means for taking an image of the subject, and a filter disposed in an incident optical path of the image fusion means for cutting off the excitation light.

When the excitation light is irradiated from the light source to the subject, the excitation light reflected from the subject is cut off by a filter, and only the fluorescence image emitted from the cells in the subject area is captured by the image carrier mounted on the tip of the scope. The image is transported by a means. Since the fluorescent image is converted into an electrical signal at the distal end of the scope and taken out of the body, deterioration in resolution is prevented.

(Example) Hereinafter, an actual FJi example of the present invention will be described based on the drawings.

First, the basic structure and operation of this embodiment will be explained using the principle block diagram shown in FIG. In Figure 1, 1 is a light guide using an optical fiber, 2 is a drive circuit 3
4 is an output signal line connected to a display means 5 such as a CRT monitor, and 4 is an output signal line connected to the light guide 1,
Control signal line 2 and output signal I! i14 constitutes a cable that is bundled together and inserted into the body.

A light source 6 for excitation light made of, for example, ultraviolet rays and a condenser lens 7 are disposed on the incident end surface side of the light guide 1, and an illumination lens 8 is disposed on the exit end surface side, that is, the tip end side of the scope. Further, on the distal end side of the scope, an objective lens 9 is arranged in parallel with the illumination lens 8, and on the spinal side of the objective lens 9 there is a filter 11 for cutting off excitation light (g external rays), and an optical amplifier 12 consisting of a microchannel plate. and C.C.D.
Solid-state image sensing devices 13 are sequentially arranged. The other ends of the control signal line 2 and the output signal line 4 are connected to the solid-state image element 13.

The amplification degree of the optical amplifier 12 is controlled by a voltage applied between both end faces of the optical amplifier 12, and the weak fluorescence emitted from the cells of the stomach wall or the like, which is the subject 14, is multiplied to a level that can be imaged. Optical amplifier 12 and prisoner imaging element 13
This constitutes an imaging means.

Next, the operation of the endoscope configured as described above will be explained.

The control signal line 2 and the output signal line 4, which are electrical signal transmission lines constituting the cable, can have a smaller diameter than optical fibers, so that the entire cable has a smaller diameter. If the cable to be inserted into the body is formed to have a small diameter, even if only the distal end of the scope is formed to have a large diameter, the pain inflicted on the subject during the setting for insertion into the body can be extremely alleviated.

When the cable is inserted into the body and the excitation light from the light source 6 is irradiated onto the subject 14 such as the stomach wall through the light guide 1 and the illumination lens 8, cells in the subject 14 are excited and fluorescence a is generated. After being multiplied to a required level by an optical amplifier 12 via an objective lens 9 and a filter 11,
The fluorescence image is formed on the image plane of the solid-state image sensor 13.

At this time, the excitation light reflected from the object 14 stops, but this excitation light is cut by the filters 11.

Then, the solid-state image sensor 1 is v-controlled by the drive 1 path 3.
3 carries the fluorescent image, and its image signal output is sent to the display means 5 via the output signal line 4 to display the fluorescent image. In this way, the fluorescent image is not transmitted through the image transmission optical fiber, but is converted into an image signal at the distal end of the scope and then taken out of the body, which prevents a decrease in resolution and improves resolution.
A highly accurate fluorescence image is displayed on the display means 5.

Next, FIG. 2 shows a first embodiment of the present invention. In this embodiment, ultraviolet rays are used as excitation light, and the subject is selectively irradiated with ultraviolet rays and visible light, so that a visible light image and a fluorescent image can be displayed superimposed on the display means. .

In FIG. 2 and FIG. 3, the same or equivalent parts or equipment as those in FIG.

First, to explain its configuration, on the incident end surface side of the light guide 1, a light beam 6 for ultraviolet light and a light source 15 for visible light are arranged in parallel. 16 is a condensing lens for visible light, and shutters 17 and 18 are provided in the optical path of ultraviolet rays and the optical path of visible light, respectively. Both shutters 17 and 18 are alternately switched in synchronization with the scanning period of one field of the solid-state image sensor 13 by a switching mechanism (not shown).

In addition, the optical amplifier 11 consisting of a microchannel plate is connected via a control line (not shown) in synchronization with the switching cycle of the light source 6.15 so that the degree of amplification is increased only during the period when the fluorescent images are fused. The applied voltage is controlled.

Further, an image signal amplifier 19 and an A/D converter 20 are sequentially connected to the output signal line 4 of the solid-state image sensor 13.
The output terminal of the /D converter 20 is connected to a first frame memory 21 for recording fluorescence image signals and a second frame memory 22 for controlling visible light image signals. The output terminals of the first and second frame memories 21 and 22 are connected to a computing unit 23, and the output line of the computing unit 23 is connected to the display means 5.

Next, the effect will be explained.

Both shutters 17 and 18 are switched in synchronization with the scanning period of the solid-state image sensor 13, and the subject 14 is alternately irradiated with ultraviolet rays and visible light. The filter 11 cuts only reflected ultraviolet rays, and the solid-state N pixel elements 13 alternately output fluorescence image signals and visible light image signals. and the first
, the memory timing of the second frame memories 21 and 22 is controlled by a control circuit (not shown), and a fluorescence image signal is recorded in the first frame memory 21.
A visible light image signal is recorded in the frame memory 22 . The 8ti calculator 23 calculates and extracts a fluorescence image signal of a certain level or higher from the first frame memory 21, and displays the fluorescence image signal and the visible light image signal from the second frame memory 22. In the means 5, a fluorescence image is displayed superimposed on a visible light image, so that identification of the invasive site of the diseased area, etc. can be performed more easily and reliably.

FIG. 3 shows a second embodiment of the invention. In this embodiment, the filter is a movable filter, and the filter is retracted from the optical path of incidence on the image carrier when necessary.

First, to explain its structure, in FIG. 3, reference numeral 11a is a movable filter, one end of which is rotatably attached to the inner wall of the cable via a hinge 24. A spring 25 is attached to the hinge 24, and the active end of the spring 25 is hooked to the movable filter 11a, so that the movable filter 11a is always given a rotational tendency in the clockwise direction in FIG. 3. . A stopper 26 is provided on the opposing surface of the inner wall of the cable, and the movable filter 11a is prevented from rotating at all times. 111 is located in the incident optical path to the imaging means. 27 is a wire as an evacuation means, the tip of the wire 27 is latched to the rotating end of the movable filter 11a, and the other end is pulled out to the outside of the body.
The tensioning operation is performed manually or the like.

Further, on the incident end side of the light guide 1, a light source for ultraviolet light and a light source for visible light are installed in parallel, similar to the one shown in FIG. A third frame memory for ultraviolet image signals is further attached to the first frame memory for signals and the second frame memory for visible light image signals.

When the movable filter 11a is positioned in the incident optical path of the image carrier and the subject is irradiated with ultraviolet rays or visible light by switching the shutter, a fluorescent image signal or a visible light image FA is output from the solid-state image sensor 13. A signal is output and recorded in the corresponding first frame memory and second frame memory, respectively.

On the other hand, when the wire 27 is pulled at the required time, the movable filter 1
1a is retracted from the optical path of incidence on the image carrier. When the subject is irradiated with ultraviolet rays by switching the shutter in this state, an image signal of ultraviolet rays is output from the solid-state image sensor 13, and this is recorded in the third frame memory.

Then, by operating the operator, etc., the fluorescence image, visible light image, and ultraviolet image are displayed individually on the display means.
Alternatively, various types of inspection information can be obtained by adjusting the levels to appropriate levels and displaying them in an arbitrary combination.

[Effects of the Invention] As explained above, according to the present invention, an image of fluorescence emitted from a subject by irradiation with excitation light is captured by an image carrier attached to the distal end of a scope and taken out of the body as an electrical signal. be done. Therefore, there is an advantage that it is not necessary to provide an optical fiber for image transmission, the cable for insertion into the body can be made thinner, and the resolution can be improved.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the basic structure of an endoscope according to the present invention, FIG. 2 is a block diagram showing the first embodiment of the present invention, and FIG.
The figure is an enlarged configuration diagram showing a portion on the distal end side of a scope in a second embodiment of the present invention. 1 light guide, 4: output signal line, 5: display means, 6: light source of excitation light, 11: filter for cutting excitation light, 11a: movable filter, 12: optical amplifier, 13: solid-state image sensor, 15: visible light source, 17.18: shutter, 24: hinge, 25: spring, 26: stopper, 27: wire (evacuation means).

Claims (3)

[Claims] (1) A light source that emits excitation light to excite a subject to obtain a fluorescent image; an imaging means attached to the distal end of a scope for imaging the subject; and a light source disposed in the incident optical path of the imaging means to excite the subject. An endoscope characterized by having a filter for cutting light. (2) The image pickup means is comprised of a solid-state image sensor and an optical amplifier disposed upstream of the solid-state image sensor. Endoscope. (3) The filter is constituted by a movable filter that can freely move in and out of the incident optical path of the imaging means, and is retracted from the incident optical path when necessary by controlling the retracting means. The endoscope according to item 1 or 2.