JPH06125911A - Endoscopic device - Google Patents

Abstract

PURPOSE:To provide an endoscopic device in which a fluorescent image can be picked up and displayed, together with an appearance image, only if fluorescence with more than predetermined luminous strength is detected. CONSTITUTION:When illuminating light involving excitation light is emitted from a light source 56, it is separated by a rotating filter 58 into normal illumination light and excitation light, which are then applied alternately to a subject 51 for inspection. The appearance image and fluorescent image of the subject for inspection are guided by an image guide fiber 53 and caused to impinge on respective first and second CCD cameras 62, 63. The fluorescence of the subject for inspection is detected by a photodetector 69 and only when its luminous strength is at or greater than a set value an image intensifier 65 is operated to double the luminous strength of the fluorescent image and then the image is picked up by the second CCD camera 63. At an image processing circuit 66 the fluorescent image is combined with the appearance image from the first camera 62 and the composite image is displayed on a monitor 67.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope apparatus for observing the condition of the inside of a human body cavity or internal organs.

[0002]

2. Description of the Related Art There are various types of endoscope devices, but a normal illumination light is applied to an object to be inspected such as internal organs of a human body,
An endoscope apparatus that displays an external image of an object to be inspected, which is illuminated thereby, on a monitor is generally used.

Also, an endoscope apparatus has conventionally been used in which a fluorescent substance such as a hematoporphyrin derivative or fluorescein is administered to an object to be inspected, and then excitation light is irradiated to display a fluorescent image emitted from the fluorescent substance on a monitor. Has been. This utilizes the property that a fluorescent substance accumulates in a lesion if the subject has a lesion.

The endoscopic device for displaying a fluorescence image has an advantage that a lesion can be easily found, but has a drawback that the appearance of an object to be inspected cannot be observed. Therefore, conventionally, there has been developed an endoscope apparatus capable of displaying an appearance image and a fluorescence image on one monitor. Such an apparatus is disclosed in Japanese Patent Laid-Open No. 63-2521.
The ones described in Japanese Patent No. 33 and Japanese Patent Application Laid-Open No. 3-97439 are known.

As shown in FIG. 5, the endoscope apparatus disclosed in Japanese Patent Laid-Open No. 63-252133 discloses a white light source 1 for obtaining a normal appearance image, and a laser emitting excitation light for a fluorescent substance. And a light source 2 respectively connected to the corresponding light guide fibers 4, 5 in the fiberscope 3. In addition, in the fiberscope 3,
An image guide fiber 7 for extracting an image of the inspection target 6 illuminated by the white light and the excitation light is provided. The image information output from here is branched by the half mirror 8 and guided to the TV camera 9 and the fluorescence image processing system 10, respectively. The TV camera 9 captures a normal appearance image and outputs the image information. On the other hand, the fluorescent image processing system 1
0 outputs fluorescence image information. These pieces of image information are combined in the image processing circuit 11, and a fluorescent image is pseudo-color mapped on the external image on the monitor 12.

In FIG. 5, reference numeral 13 is an image guide fiber for taking out a fluorescence spectrum image, a high-sensitivity camera 15 is connected to an output end of the fluorescence spectroscopic image via a spectroscope 14, and an analysis circuit 16 is used. The fluorescent spectrum image display device 17 outputs a fluorescent spectrum image.

On the other hand, the endoscope apparatus disclosed in Japanese Patent Laid-Open No. 3-97439 has a configuration as shown in FIG. 6, and includes a fiberscope 20, a TV camera 21, and an image processing circuit 2.
2 and a monitor 23. The endoscope device includes a light source 24 that emits illumination light including excitation light. The illumination light emitted from the light source 24 is transmitted through the first rotary filter 25 to generate the illumination light and the excitation light. Can be alternately guided to the light guide fiber 26 in the fiber scope 20. In addition, a second rotary filter 28 that rotates in synchronization with the first rotary filter 25 is attached in front of the fixed image sensor 27 of the TV camera 21, and as a result, the light is output from the image guide fiber 29. The appearance image and the fluorescence image are alternately incident on the solid-state imaging device 27. The image information corresponding to each of the appearance image and the fluorescence image from the solid-state image sensor 27 is combined in the image processing circuit 22, and the combined image is displayed on the monitor 23.

[0008]

In the conventional appearance image / fluorescence image combining type endoscope apparatus as described above, the operator must always observe the fluorescence image and the appearance image on the monitors 12 and 23. Therefore, the operator tends to feel tired and the examination time tends to be long. A long-term examination is painful to the subject. In addition, even a small lesion may be overlooked because the amount of fluorescence in that portion is small.

In addition, the endoscope apparatus shown in FIG.
No. 52133), the white light source 1, the laser light source 2, and the two light guide fibers 4 and 5 connected to each are required, which causes a problem that the device becomes large.

Furthermore, the endoscope apparatus shown in FIG.
No. 97439), a single fixed image sensor 27 captures a fluorescent image and an external image, but since the fluorescent image is generally much darker than the external image, only a bright fluorescent image can be captured. A high-sensitivity TV camera may be used to solve this problem, but the high-sensitivity TV camera has a low spatial resolution and is not suitable for capturing a normal appearance image.

The present invention has been made in view of the above circumstances, and an object thereof is to make it possible to capture and display a fluorescent image together with an external image only when detecting fluorescent light having a predetermined light intensity or more. It is to provide a mirror device.

[0012]

In order to achieve the above object, the invention according to claim 1 provides an appearance image obtained when a subject to be inspected containing a fluorescent substance is irradiated with normal illumination light, In an endoscope apparatus of an appearance image / fluorescent image combination type that displays a fluorescent image obtained when irradiating the fluorescent substance with excitation light, a light source that emits illumination light including excitation light, and illumination light emitted from the light source. , And a filter means for alternately transmitting the excitation light contained in the illumination light, a light guide means for guiding the illumination light and the excitation light transmitted through the filter means to an object to be inspected, an external image and a fluorescent image of the object to be inspected Guide means for guiding the light, branching means for branching the output light from the image guide means into a first optical path and a second optical path, and a first
A first image pickup means placed in the optical path for taking an external image, and a second image pickup means placed in the second optical path for taking a fluorescent image;
Fluorescence guide means for guiding the fluorescence emitted from the object to be inspected, light detection means for detecting the light intensity of the output light from the fluorescence guide means, and light when the light intensity of the output light from the fluorescence guide means is equal to or greater than a set value. A control unit that operates the second image pickup unit according to the output of the detection unit, an image processing unit that processes image information from the first image pickup unit and the second image pickup unit, and an image processed by the image processing unit are displayed. And an image display means.

The endoscope apparatus according to a second aspect of the invention is the photodetector for detecting the light intensity of the fluorescence, wherein the fluorescence guide means in the first aspect of the invention is omitted. Is adapted to detect the light intensity of the output light from the image guide means corresponding to the fluorescence.

Such an endoscope apparatus according to the present invention preferably includes fluorescent display means for displaying the output of the light detection means.

[0015]

In the present invention, the rotating filter irradiates the inspection object with illumination light and excitation light alternately, and the appearance image and the fluorescence image of the inspection object obtained thereby are alternately imaged in the first and second images. It is imaged by means. In the present invention, the light intensity of the fluorescence emitted from the object to be inspected is detected, the detected value and the set value are compared, and when the detected value exceeds the set value, that is, when abnormal fluorescence is emitted. , The fluorescence image is combined with the appearance image.

According to the first aspect of the invention, the fluorescence is transmitted by the fluorescence guide means provided separately from the image guide means. Further, as in the invention of claim 2, of the output light emitted from the image guide means, the light intensity of the light corresponding to the fluorescence may be detected.

The fluorescent display means displays the output information of the light detection means, thereby making it possible for the operator to recognize the presence of abnormal fluorescence.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an endoscope apparatus according to the first embodiment of the present invention. In the figure, reference numeral 50 is a fiberscope, which is a flexible elongated insertion portion 50a to be inserted into the body.
And the operation portion 5 provided at the base of the insertion portion 50a
It consists of 0b. The operation portion 50b has such a form that the operator can perform an operation such as angle, air / water supply, and suction with one hand, and an optical fiber (light guide means for guiding illumination light from this portion 50b to the object 51 to be inspected). In the following, a "light guide fiber" 52, an optical fiber (hereinafter referred to as "image guide fiber") 53 as image guide means for guiding an image of the inspection object 51, and further fluorescence for guiding fluorescence emitted by the inspection object 51. An optical fiber (hereinafter referred to as “fluorescent guide fiber”) 54 as a guide means is inserted.

A light source 56 is arranged at a position facing the incident end face of the light guide fiber 52 via a condenser lens 55. The illumination light emitted from the light source 56 also includes excitation light for the fluorescent substance contained in the inspection object 51. Further, a rotary filter 58, which is rotationally driven by a motor 57, is arranged between the condenser lens 55 and the incident end face of the light guide fiber 52. The rotary filter 58 has at least one pair of a first filter 58a that transmits illumination light in almost all wavelength bands and a second filter 58b that transmits only excitation light. These filters 58a and 58b are alternately arranged in the circumferential direction, and pass through the optical path of the light source 56 when the rotary filter 58 rotates.

The optical path of the output light from the image guide 53 is branched by a half mirror 59 into a first optical path 60 and a second optical path 61, and a first CCD camera (first image pickup means) 62 is placed in the first optical path 60. A second CCD camera (second image pickup means) 63 is placed in the second optical path 61. Second CCD
A filter 64 for removing stray light other than fluorescence is arranged between the camera 63 and the half mirror 59, and an image intensifier 65 is arranged between the filter 64 and the second CCD camera 63. ing. The first and second CCD cameras 62, 63 are connected to an image processing circuit 66, image information from each is subjected to processing such as composition in the image processing circuit 66, and the composite image is displayed on a monitor 67. .

A photodetector 69 is arranged at a position facing the emission end face of the fluorescence guide fiber 54, with a filter 68 for removing stray light other than fluorescence interposed therebetween. The photodetector 68 detects the light intensity of the received light, and its output terminal is connected to the optical signal processing circuit 71 of the control circuit 70. A gate circuit 72 is connected to the optical signal processing circuit 71, and the gate circuit 72 controls the operation of the image intensifier 65 according to the signal from the optical signal processing circuit 71. In addition, the optical signal processing circuit 71
A fluorescent display device 73 is connected to. The fluorescent display device 73 uses the optical signal from the photodetector 69 as the inspection target 5
It can be displayed as sound information or light information corresponding to one fluorescence, or as a number.

The operation of the endoscope apparatus having such a configuration will be described with reference to the timing chart of FIG.

First, when the illumination light is emitted from the light source 56 and enters the rotary filter 58 through the condenser lens 55, it passes through the filters 58a and 58b of the rotary filter 58 which is rotationally driven by the motor 57 to illuminate it. Light and excitation light are alternately incident on the incident end surface of the light guide fiber 52 (see FIG. 2A). This incident light is guided to the inside of the body by the light guide fiber 52 and is irradiated on the inspection object 51.

The reflected light reflected from the inspection object 51 by the irradiation of the illumination light and the fluorescence generated from the fluorescent substance in the inspection object 51 by the irradiation of the excitation light are transmitted by the fluorescence guide fiber 54 and passed through the filter 68. It is incident on the photodetector 69. FIG. 2B shows the output from the photodetector 69, which corresponds to the light intensity of the fluorescence emitted from the inspection object 51. The output signal from the photodetector 69 is sent to the optical signal processing circuit 71. The optical signal processing circuit 71, as shown in FIGS.
The output signal from the photodetector 69 is sampled as the detection value of the fluorescence light intensity only during the ON state of the counter operation after the start of irradiation of the excitation light. The fluorescent display device 73 displays the detected value collected by the optical signal processing circuit 66 in an appropriate form such as sound information and informs the operator of the fluorescent state. Further, the optical signal processing circuit 66 compares the detected value collected with the previously stored set value. Then, when the detected value exceeds the set value, the optical signal processing circuit 66 determines that abnormal fluorescence is emitted from the inspection object 51 (see FIG. 2E), and only the fluorescence image is obtained. For multiplication, a signal is sent to the gate circuit 72 in synchronization with the rotary filter 58 to turn on the image intensifier 65.

On the other hand, the fluorescence image and the normal appearance image from the object 51 to be inspected are transmitted by the image guide fiber 53 and, after passing through the relay lens 74, are split by the half mirror 59 into the first optical path 60 and the second optical path 61. It First optical path 6
Image information passing through 0 is captured by the first CCD camera 62. Further, the image information passing through the second optical path 61 is the filter 6
After the stray light is removed at 4, the light is incident on the image intensifier 65. The information of the fluorescence image and the appearance image is always incident on the image intensifier 65, but the image intensifier 65 is used only when the optical signal processing circuit 71 determines that abnormal fluorescence is present in the inspection object 51. Operate. More specifically, as shown in FIG. 2F, the image intensifier 65 amplifies the light intensity of the image by the signal from the control circuit 70 only during the period when the fluorescent image is seen, and the second CCD camera in the rear side. At 63, this enhanced fluorescence image is captured. The appearance image with high light intensity is
It is blocked by turning off the image intensifier 65, and does not enter the second CCD camera 63.

In the image processing circuit 66, the rotary filter 5
In synchronism with 8, the external image of the image captured by the first CCD camera 62 is captured as image information (see FIG. 2).
(G)). Then, as shown in FIG. 2H, the image processing circuit 66 sequentially outputs the image information of the appearance image and the fluorescence image from the second CCD camera 63, and displays it on the monitor 67. Since the cycle of irradiating the excitation light and the observation light is very short, by alternately outputting the image information of the appearance image and the fluorescence image, both images are displayed on the monitor 67 in a superimposed manner.

As shown in FIG. 1, a sensitivity adjusting knob 75 is provided on the operation portion 50b of the fiberscope 50,
It is also possible to manually turn the knob 75 to adjust the degree of light enhancement of the image intensifier 65. In this case, the fluorescent image can be displayed brightly on the monitor 67, and the state of the lesion area of the inspection target 51 can be easily grasped.

An image changeover switch 76 is provided on the operation portion 50b of the fiberscope 50, and the image processing circuit 6 is provided.
It is also possible to make the monitor 67 display only one of the external image and the fluorescent image on the monitor 67.

Further, in the optical signal processing circuit 71, by making the set value of the light intensity variable, it is possible to react to extremely weak fluorescence. Usually, in an endoscopic examination, a fluorescent substance is administered to a subject 51 to be inspected, and a place where the fluorescent substance is accumulated is searched. However, according to the present invention, since extremely weak fluorescence can be detected, it becomes possible to detect a fluorescent substance possessed by the human body,
It is not necessary to separately administer the fluorescent substance.

FIG. 3 shows a second embodiment of the present invention.
In the figure, the same or corresponding parts as those in the endoscope apparatus of the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. Unlike the endoscope device according to the first embodiment, the endoscope device according to the second embodiment has no fluorescent guide fiber. In addition, in the second embodiment, the second optical path 61 branched by the half mirror 59 and the third optical path 61 ′ which goes straight as it is by the other half mirror 80.
The image intensifier 65 and the second CCD camera 63 are placed on the optical path 61 'in the optical path 81',
The photodetector 69 is placed in the optical path 81. Half mirror 59
In the second optical path 61 between the half mirror 80 and the half mirror 80, there is a chopper 82 and a filter 6 for removing stray light other than fluorescence.
4 are arranged.

In this structure, although the fluorescent guide fiber is not provided, the fluorescent light from the inspection object 51 passes from the image guide fiber 53 to the optical paths 61 and 81.
Since the light is incident on the photodetector 69 through the above, there is substantially no difference from the operation of the first embodiment. The difference is the second
As can be understood from FIGS. 4B and 4C, which are timing charts showing the operation of the embodiment, the second optical path 61 is provided during a period in which normal illumination light is emitted by the chopper 82 synchronized with the rotary filter 58. Is blocked and the light of the appearance image is prevented from entering the photodetector 69.

In the second embodiment, since the fluorescent guide fiber is unnecessary, it is possible to reduce the diameter of the fiberscope 50, or when the ordinary fiberscope 50 having three holes is used, The remaining holes can be used for other manipulators.

The image processing circuit 66 in the above-mentioned first and second embodiments includes the first and second CCD cameras 62 and 6.
The image information of No. 3 is alternately sent to the monitor 67 for composition, but other types of image processing circuits can be used, and the image display method is limited to the superimpose format. Absent.

[0035]

As described above, according to the present invention, the fluorescent image is displayed on the monitor together with the external image only when the object to be inspected has abnormal fluorescent light. Therefore, the operator always obtains the external image and the fluorescent image. Eliminates the need to compare and simplifies inspection.
According to the invention of claim 3, the presence of fluorescence can be separately notified to the operator by using the fluorescence display means. Therefore, the operator is less tired, the examination is completed in a short time, and the pain to the subject is reduced.

Further, since the light intensity of fluorescence is detected separately from the image, it is possible to detect even weak fluorescence that cannot be detected by the camera. Therefore,
There is no need to administer a fluorescent substance such as porphyrin, and it becomes possible to search for a lesion using the fluorescent substance that the human body has. This is an inspection method that cannot be performed by the conventional device.

Further, in the invention according to claim 2, since the fluorescence is also derived by using the image guide means for extracting the fluorescence image, the fluorescence guide means becomes unnecessary and the diameter of the fiberscope can be reduced. Alternatively, in the case of an existing fiberscope having many holes, the holes can be effectively used.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an endoscope apparatus according to a first embodiment of the present invention.

FIG. 2 is a timing chart showing the operation of the endoscope apparatus according to the first embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of an endoscope apparatus according to a second embodiment of the present invention.

FIG. 4 is a timing chart showing the operation of the endoscope apparatus according to the second embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration of a conventional endoscope apparatus.

FIG. 6 is a block diagram showing a configuration of another conventional endoscope apparatus.

[Explanation of symbols]

50 ... Fiberscope, 51 ... Inspected object, 52 ...
Light guide fiber, 53 ... Image guide fiber, 54 ... Fluorescence guide fiber, 56 ... Light source, 58
... Rotating filter, 59 ... Half mirror, 60 ... First optical path, 61, 61 '... Second optical path, 62 ... First CCD camera, 63 ... Second CCD camera, 65 ... Image intensifier, 66 ... Image processing circuit, 67 … Monitor, 6
9 ... Photodetector, 70 ... Control circuit, 71 ... Optical signal processing circuit, 72 ... Gate circuit, 73 ... Fluorescent display device.

Claims (3)

[Claims] 1. An endoscope for displaying an appearance image obtained when a subject to be inspected containing a fluorescent substance is irradiated with normal illumination light and a fluorescent image obtained when the excitation light for the fluorescent substance is irradiated. In the mirror device, a light source that emits illumination light containing excitation light, a filter means that alternately transmits the illumination light emitted from the light source, and the excitation light included in the illumination light, and an illumination that transmits the filter means. Light guide means for guiding light and excitation light to an object to be inspected, image guide means for guiding an external image and a fluorescent image of the object to be inspected, and output light from the image guide means is branched into a first optical path and a second optical path. A branching unit, a first image pickup unit placed in the first optical path for picking up an external image, a second image pickup unit placed in the second optical path for picking up a fluorescent image, and fluorescence emitted from the inspection target. Firefly leading Guide means, light detection means for detecting the light intensity of the output light from the fluorescence guide means, and depending on the output of the light detection means when the light intensity of the output light from the fluorescence guide means is a set value or more. Control means for operating the second imaging means, an image processing means for processing image information from the first imaging means and the second imaging means, and an image display for displaying an image processed by the image processing means. An endoscopic device comprising: 2. An endoscope for displaying an appearance image obtained when a subject to be inspected containing a fluorescent substance is irradiated with normal illumination light and a fluorescent image obtained when the excitation light for the fluorescent substance is irradiated. In the mirror device, a light source that emits illumination light containing excitation light, a filter means that alternately transmits the illumination light emitted from the light source, and the excitation light included in the illumination light, and an illumination that transmits the filter means. Light guide means for guiding light and excitation light to an object to be inspected, image guide means for guiding an external image and a fluorescent image of the object to be inspected, and output light from the image guide means is branched into a first optical path and a second optical path. A branching unit, a first image pickup unit placed in the first optical path for picking up an external image, a second image pickup unit placed in the second optical path for picking up a fluorescent image, and fluorescence emitted from the inspection target. Corresponds to Light detection means for detecting the light intensity of the output light from the image guide means, and the light detection when the light intensity of the output light from the image guide means corresponding to the fluorescence emitted from the inspection target is equal to or more than a set value. Control means for operating the second imaging means according to the output of the means, image processing means for processing image information from the first imaging means and the second imaging means, and an image processed by the image processing means And an image display unit for displaying the endoscopic device. 3. The endoscope apparatus according to claim 1, further comprising fluorescent display means for displaying an output of the light detection means.