JP2007075445A - Image pickup system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image pickup system which can obtain an observation image of the vascular running state at a deep part of a living body. <P>SOLUTION: The image pickup system includes a light source means to generate the light in an infrared region exceeding at least a wavelength of 1,200 nm, an image pickup means having the sensitivity in the infrared region exceeding the wavelength of 1,200 nm, and a spectral diffraction means to control the wavelength so that the image pickup light used for the image capturing by the image pickup means which receives the reflection light or the transmission light of the light emitted to a subject has only a prescribed wavelength band exceeding the wavelength of 1,200 nm, wherein the prescribed wavelength band is the wavelength band including at least an optical absorption peak of the blood vessel. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an imaging system, and more particularly to an imaging system capable of obtaining a blood vessel running state.

Conventionally, as a technique for identifying blood vessel running, there is a method of observing using a hemoglobin absorption characteristic of 700 nm to 1000 nm in a 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.

  The present invention has been made in view of the above-described points, and an object thereof is to provide an imaging system capable of obtaining an observation image of a running state of a blood vessel in a deep part of a living body.

  A first imaging system according to the present invention includes a light source unit that generates light in an infrared region exceeding a wavelength of at least 1200 nm, an imaging unit having sensitivity in an infrared region exceeding the wavelength of 1200 nm, and a subject. Spectroscopic means for limiting the wavelength so that imaging light used for imaging by the imaging means that receives reflected light or transmitted light in the light has only a predetermined wavelength band exceeding the wavelength of 1200 nm, and The predetermined wavelength band is a wavelength band including at least a light absorption peak of a blood vessel.

  The second imaging system according to the present invention is the first imaging system, wherein the spectroscopic unit is configured to emit only the predetermined wavelength band with respect to light emitted from the light source unit or light incident on the imaging unit. It is characterized by comprising filter means for transmitting or selectively reflecting means for selectively reflecting.

  According to a third imaging system of the present invention, in the first imaging system, the spectroscopic unit is configured by a light emitting element that is provided in the light source unit and emits light of the predetermined wavelength band. To do.

  According to a fourth imaging system of the present invention, in the first imaging system, the predetermined wavelength band is a band in which a light transmittance of a predetermined living tissue is equal to or higher than a light transmittance of a blood vessel wall or blood. It is a wavelength band including

  According to a fifth imaging system of the present invention, in the fourth imaging system, the predetermined biological tissue is fat.

  According to a sixth imaging system of the present invention, in the fourth or fifth imaging system, the predetermined wavelength band is a wavelength band including at least a band of 1200 nm to 1600 nm and a band of 1850 nm to 2200 nm. To do.

  According to a seventh imaging system of the present invention, in the fourth or fifth imaging system, the predetermined wavelength band is a wavelength band including a band of at least 1200 nm to 2500 nm.

  According to an eighth imaging system of the present invention, a light source unit that generates light in an infrared region exceeding a wavelength of at least 1200 nm, an imaging unit having sensitivity in an infrared region exceeding the wavelength of 1200 nm, and an object are irradiated Spectroscopic means for limiting the wavelength so that imaging light used for imaging by the imaging means that receives reflected light or transmitted light in the light has only a predetermined wavelength band exceeding the wavelength of 1200 nm, and The predetermined wavelength band is a wavelength band including a wavelength at which a difference between the light transmittance of a predetermined biological tissue and blood vessel wall and the light transmittance of blood is a maximum.

  According to a ninth imaging system of the present invention, in the eighth imaging system, the predetermined living tissue is fat.

  According to a tenth imaging system of the present invention, in the eighth or ninth imaging system, the predetermined wavelength band is at least one band among bands of 1650 ± 50 nm, 1850 ± 50 nm, or 2200 ± 50 nm. It is characterized by including.

  According to the imaging system of the present invention, it is possible to obtain an observation image of a running state of a blood vessel in a deep part of a living body.

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

(First embodiment)
1 to 7 relate to a first embodiment of the present invention. FIG. 1 is a diagram illustrating an overall configuration of an imaging system according to the first embodiment. FIG. 2 is a conceptual operation explanatory view of observing a blood vessel by irradiating a biological tissue as a subject with infrared light. FIG. 3 is a diagram showing the permeability characteristics of blood vessels and fat in living tissue. FIG. 4 is a diagram illustrating a schematic image example obtained when a blood vessel covered with fat is observed with light in a visible region. FIG. 5 is a diagram illustrating a schematic image example obtained by the imaging system of the first embodiment. FIG. 6 is an overall configuration diagram of an imaging system according to a first modification example of the first embodiment. FIG. 7 is an overall configuration diagram of an imaging system according to a second modification example of the first embodiment.

As shown in FIG. 1, an imaging system 1 according to the first embodiment of the present invention includes a light source device 3 that irradiates, as illumination light, light including an infrared region with respect to, for example, a living body 2 as a subject, and the illumination light. An infrared imaging camera (hereinafter simply abbreviated as “infrared camera”) 4 that performs imaging with light reflected in the living body 2 irradiated with light or light in the infrared region of transmitted light as indicated by a two-dot chain line; The control device 5 performs signal processing on the image signal picked up by the infrared camera 4 and the monitor 6 displays the video signal output from the control device 5.
The light source device 3 incorporates a lamp 11 such as a halogen lamp or a tungsten lamp that generates illumination light ranging from the visible region to an infrared region exceeding a wavelength of at least 1200 nm.

Further, it is desirable that the lamp 11 has a high emission intensity in a specific narrow band wavelength band to be described later. As this lamp 11, for example, a halogen lamp having continuous light emission characteristics up to a wavelength band exceeding 3000 nm can be used.
Illumination light from the lighting of the lamp 11 is irradiated to the living body 2 through the illumination lens 12. The reflected light when irradiated on the living body 2 is imaged by the imaging element 15 via the filter 13 and the imaging lens 14 constituting the infrared camera 4 as the imaging means having sensitivity in the infrared region exceeding the wavelength of at least 1200 nm. The image is formed on the surface.
In FIG. 1, the infrared camera 4 is shown configured to receive reflected light from the living body 2 when illuminated by the living body 2 from the light source device 3, but for example, as shown by a two-dot chain line, The apparatus 3 may be arranged to receive light transmitted by the living body 2.

The imaging device 15 used in the infrared camera 4 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.
Further, as shown in FIG. 3, the filter 13 disposed in front of the imaging element 15 has a minimum blood vessel transmittance, that is, a blood vessel absorbance peaked in a wavelength region exceeding the wavelength of 1200 nm. A specific narrow band wavelength is set so that the wavelength is transmitted in a narrow band. Specifically, the filter 13 transmits a first narrowband wavelength band that transmits 1450 nm ± 50 nm (indicated by symbol A in FIG. 3) and a first narrowband wavelength band that transmits 1950 nm ± 50 nm (indicated by symbol B in FIG. 3). The transmission characteristic is set to transmit one of the two narrow-band wavelength bands.

That is, in the present embodiment, the imaging light incident on the imaging device 15 that is arranged on the imaging means side and that captures (receives light) to obtain image information is set to have a specific narrowband wavelength. As in the case of the second embodiment to be described later, by limiting the wavelength band of the illumination light on the illumination side, the wavelength band of the imaging light imaged by the imaging element 15 is also a specific narrowband wavelength. May be set.
Further, these narrowband wavelength bands are selected and set so as to be a wavelength band in which the transmittance of fat tissue is sufficiently large as shown in FIG. Specifically, in the first narrowband wavelength band and the second narrowband wavelength band, the value of fat transmittance is more than double that of the blood vessel transmittance.

  In addition, since the absorption peak of the blood vessel is wider on the second narrow band wavelength band side than on the first narrow band wavelength band side, the transmission wavelength range by the filter 13 is set to the first narrow band wavelength band side. It may be set wider than in the case of.

  Note that, as the specific narrowband wavelength by the first narrowband wavelength band and the second narrowband wavelength band, for example, a case where the transmission wavelength range is set to a narrow band of about 100 nm is shown, but the present invention is not limited to this. What is necessary is just to set to a narrow band of about several tens of nm to 100 nm. By setting in this way, it is possible to permeate the fat tissue portion with a small amount of attenuation when it is desired to grasp the running state of the blood vessel in a state where the blood vessel is covered with fat, as will be described later. However, when imaging light reflected by the blood vessel tissue under the fat tissue, the image can be taken in a high S / N state.

  Although the living body 2 is irradiated with illumination light from the visible region to the infrared region, the optical image formed on the imaging element 15 is the first narrowband wavelength band or the second narrowband transmitted through the filter 13. This is due to a specific narrow-band wavelength light in the wavelength band.

In other words, in the present embodiment, the wavelength of the imaging light is limited by the filter 13 so that the light imaged by the imaging element 15 is based on the specific narrowband wavelength light on the longer wavelength side than the wavelength of 1200 nm. Forms spectroscopic means.
The optical image formed on the imaging surface of the image sensor 15 is photoelectrically converted by the image sensor 15. When a drive signal is applied to the image pickup device 15 from a drive circuit (not shown) in a camera control unit (abbreviated as CCU) 16 built in the control device 5, a photoelectrically converted signal is used as an image pickup signal. 15 is output. This imaging signal is input to the CCU 16 and converted into a video signal by a video signal generation circuit (not shown) in the CCU 16.

The video signal is output to the monitor 6, and an image captured by the image sensor 15 is displayed on the display surface of the monitor 6. In addition, the control device 5 includes a lighting control circuit 17 that drives the lamp 11 in the light source device 3 to light and controls the amount of light emission.
The imaging system 1 of the present embodiment having such a configuration has an operation as shown in the schematic diagram of FIG. FIG. 2 shows the case of infrared observation using reflected light.
As shown in FIG. 2, illumination light covering the visible region to the infrared region is irradiated from the light source device 3 to the living body 2. Then, the reflected light from the living body 2 is imaged by the infrared camera 4. In the living body 2, the blood vessel 19 is often covered with the tissue of fat 18.

For this reason, the amount of attenuation increases in the infrared region, which is shorter than the wavelength of about 1200 nm, as well as in the case of illumination light in the visible region, and imaging is performed with the reflected light from the blood vessel 19 below the fat 18. Becomes difficult.
In contrast, in the present embodiment, the imaging element 15 having sensitivity on the longer wavelength side than the wavelength of 1200 nm is used, and illumination light including a longer wavelength side than the wavelength of 1200 nm is irradiated as illumination light. Further, a filter 13 having a characteristic of selectively transmitting a specific narrowband wavelength light in the first narrowband wavelength band or the second narrowband wavelength band in which the absorbance to the blood vessel 19 reaches a peak before the image sensor 15. Is arranged.
Further, this specific narrow-band wavelength light has a high transmittance to the tissue of fat 18, and therefore reaches the tissue of the blood vessel 19 with a small amount of attenuation. Since the light is absorbed by the tissue of the blood vessel 19, the intensity of the reflected light is greatly different between the reflected light from the tissue of the blood vessel 19 and the reflected light from the surrounding tissue such as fat 18 (the reflected light is different from the reflected light). Become). That is, as shown by the dotted line in FIG. 2, the reflected light reflecting the traveling state of the blood vessel 19 is obtained.

Therefore, when the image signal picked up by the image pickup device 15 is subjected to signal processing by the CCU 16 to generate a video signal and displayed on the monitor, an image as shown in FIG. 5 can be obtained.
When the blood vessel 19 covered with the tissue of fat 18 is observed as described above, when observed with light in the visible region, the attenuation is large due to the tissue of fat 18 as shown in FIG. Thus, the blood vessel 19 is displayed as an image that is hardly visible.
On the other hand, when observed with a specific narrowband wavelength light on the longer wavelength side than the wavelength of 1200 nm in the present embodiment, the blood vessel 19 can be displayed as an image having a large contrast as shown in FIG. . For this reason, the traveling state of the blood vessel 19 can be grasped.

In the above description, the configuration and operation for observing using the infrared camera 4 have been described. However, as shown in FIG. 6, a configuration such as the imaging system 1B of the first modification example for observing the inside of a living body may be used.
An imaging system 1B according to a first modification shown in FIG. 6 is a camera-equipped endoscope in which a camera head 23 having a built-in imaging means is attached to, for example, an optical endoscope 22 inserted into an abdominal part 2B (of a living body 2). (Hereinafter simply abbreviated as a scope) 24, a light source device 25 that supplies illumination light to the optical endoscope 22, a CCU 26 that performs signal processing on the imaging means built in the camera head 23, and an output from the CCU 26 When a standard video signal is input, the monitor 27 displays an endoscopic image picked up by the image pickup means.

The optical endoscope 22 includes, for example, a rigid insertion portion 31, a grip portion 32 provided at the rear end of the insertion portion 31, and an eyepiece portion 33 provided at the rear end of the grip portion 32. The light guide cable 34 is connected to the base of the grip portion 32.
A light guide 35 that transmits illumination light is inserted into the insertion portion 31, and the light guide 35 is provided at an end portion thereof via a light guide cable 34 that is connected to a base on the side of the grip portion 32. A connector 36 is detachably connected to the light source device 25.
The light source device 25 is provided with a lamp 38 such as a halogen lamp that is turned on by a lamp lighting power source supplied from a lamp lighting control circuit 37. The lamp 38 has an infrared region exceeding a wavelength of at least 1200 nm as described above. Generate light.
The light from the lamp 38 is collected by a condenser lens 39 disposed on the illumination optical path, and the illumination light is incident on the incident end face of the light guide 35 of the light guide connector 36. It is transmitted to the front end surface (outgoing end surface).

And it radiates | emits from the front end surface of the said light guide 35, and irradiates illumination light to the observation object site | part 40 side, such as a stomach, as a to-be-photographed object in the abdominal part 2B, and illuminates the observation object site | part 40.
An objective lens 41 is attached to an observation window provided adjacent to the illumination window at the distal end of the insertion portion 31 to connect an optical image of a site to be observed such as an illuminated affected area. The optical image is transmitted to the rear end face side by a relay lens system 42 as an image guide.
The transmitted optical image can be enlarged and observed by an eyepiece lens 43 provided on the eyepiece 33. When the camera head 23 is attached to the eyepiece 33, an optical image transmitted through the imaging lens 44 in the camera head 23 is formed on the imaging device 15.
In this case, for example, in the optical path between the imaging lens 44 and the imaging element 15, there are a first narrowband wavelength band that transmits 1450 nm ± 50 nm and a second narrowband wavelength band that transmits 1950 nm ± 50 nm. A filter 13 having a transmission characteristic that transmits one side is disposed.

A camera cable 47 extended from the camera head 23 is connected to the CCU 26. The CCU 26 includes an image sensor drive circuit 48 and a signal processing circuit 49, and the image sensor drive circuit 48 applies an image sensor drive signal to the image sensor 15.
The image signal photoelectrically converted by the image sensor 15 by the application of the image sensor drive signal is input to the signal processing circuit 49. The signal processing circuit 49 performs signal processing for generating a video signal for the input imaging signal.
The generated video signal is output to the monitor 27, and an image captured by the image sensor 15 is displayed on the display surface of the monitor 27.
In addition, a dimming signal representing the average brightness in the several frame period with respect to the luminance level of the video signal in the signal processing circuit 49 is input to the lamp lighting control circuit 37 in the light source device 25. The lamp lighting control circuit 37 controls the light emission amount of the lamp 38 based on a difference signal between a dimming signal and a reference brightness signal (not shown).

Next, an operation in the case where a surgical operation is performed by observing the stomach to be treated in the abdomen 2B by using the imaging system 1B under the scope 24 will be described.
With this imaging system 1B according to this modification, as shown in FIG. 6, the insertion portion 31 of the scope 24 is inserted into the abdominal portion 2B through a trocar (not shown), and the treatment target is cancerous covered with a omentum, for example. In order to cut the stomach, it may be necessary to check the running state of the blood vessel 19.
In this case, in the case of an adult or the like, the greater omentum is thickened in the tissue with the fat 18, and as described above, in the visible light or near infrared light, the running state of the blood vessel 19 due to the fat 18 tissue. It becomes difficult to grasp.

On the other hand, as shown in FIG. 6, when the blood vessel 19 is running on the lower side (inner side) covered with the observation target part 40 made of the tissue of fat 18 such as the greater omentum, in the present embodiment, By imaging using light of a specific narrow band wavelength exceeding the wavelength of 1200 nm, an image capable of grasping the running state of the blood vessel 19 can be obtained as shown on the monitor 27 (or FIG. 5) of FIG.
As described above, according to the first modification example of the present embodiment, even when inserted into a body cavity and performing an endoscopic surgical operation, the running state of the blood vessel 19 below the fat 18 and the like can be grasped and smooth. In addition, treatment can be performed in a short time. Therefore, the operation time can be greatly shortened, and the burden on both the operator and the patient can be greatly reduced.
FIG. 7 shows an imaging system 1C of the second modification. In this imaging system 1C, in the imaging system 1B shown in FIG. 6, a dichroic mirror 51 as a selective reflecting means for selectively reflecting light of a specific narrow band wavelength is disposed in the camera head 23, and this dichroic is arranged. The image sensor 15 is disposed at the image formation position reflected by the mirror 51.

In addition, a scope 24C using a camera head 23C in which an imaging element 52 for normal light observation, such as a CCD, is disposed at an imaging position on the transmitted light side of the dichroic mirror 51 is employed. The image sensor 52 is a simultaneous color image sensor including an optical color separation filter such as a mosaic filter that transmits light in the R, G, and B wavelength bands in the visible region.
In addition, the CCU 26C in the present modification includes a signal processing circuit 26C having a signal processing function for the two image pickup devices 15 and 52. The signal processing circuit 26 </ b> C includes an image sensor driving circuit 48 that drives the image sensors 15 and 52, and a signal processing circuit 49 </ b> C that performs signal processing on the two image sensors 15 and 52.
Then, both video signals generated by the signal processing on the imaging signals of the imaging elements 15 and 52 are mixed in the signal processing circuit 49C and output to the monitor 27, and images 27a and 27a respectively captured by both the imaging elements 15 and 52 are captured. 27b can be displayed side by side at the same time.

The two image sensors 15 and 52 have the same number of pixels, for example, and can be driven in common by one image sensor drive circuit 48. Of course, they may be driven separately.
According to this modification, in addition to the image 27a for infrared observation, a color image 27b for normal observation in the visible region can also be obtained.
For this reason, since the color image 27b for normal observation and the image 27a for infrared observation can be obtained with one scope 24C, surgery can be performed with one scope 24C without using a plurality of scopes. Surgery can be performed in a short time. Therefore, the burden on both the operator and the patient can be reduced.
In FIG. 7, a half prism and a filter 13 may be used instead of using the dichroic mirror 51.

(Second Embodiment)
Next, a second embodiment of the present invention will be described.

  8 and 9 relate to the second embodiment of the present invention. FIG. 8 is an overall configuration diagram of an imaging system according to the second embodiment. FIG. 9 is an overall configuration diagram of an imaging system according to a modification example of the second embodiment.

In the first embodiment, the illumination light is irradiated to the living body 2 as a subject using broadband illumination light including a specific narrowband wavelength exceeding a wavelength of 1200 nm from the visible region, and is provided on the imaging means side. The light having a specific narrow band wavelength is incident on the image sensor 15 for infrared observation by the filter 13 or the like functioning as a means. On the other hand, in the present embodiment, the filter 13 is arranged on the light source device side, and the light irradiated on the living body 2 as the subject is set to have a specific narrow band wavelength exceeding the wavelength of 1200 nm. is there.
The imaging system 1D has a configuration in which the filter 13 disposed in the camera head 23 in the imaging system 1B in FIG. 6 is changed to be disposed in the light source device 25, for example.

That is, the imaging system 1D includes a camera head 23D in which the filter 13 disposed in the camera head 23 is removed instead of the camera head 23 in the imaging system 1B in FIG. A light source device 25D is used.
In the light source device 25D, for example, the filter 13 is disposed on the optical path between the lamp 38 and the condenser lens 39. Other configurations are the same as those of the imaging system 1B of FIG. According to the present embodiment, it is possible to obtain an image that can grasp the running state of the blood vessel 19 in substantially the same manner as in the case of FIG. 6 in the first embodiment.
Next, a modification of this embodiment will be described.

The imaging system 1E uses the infrared LED array 61 instead of the lamp 38 and the filter 13 in the light source device 25D and emits the infrared LED array 61 instead of the lamp lighting control circuit 37 in the imaging system 1D of FIG. A light source device 25E having a configuration using the LED drive control circuit 62 to be driven is used.
In this case, the infrared LED array 61 employs a plurality of infrared LEDs 61a having a characteristic of emitting light at a specific narrow band wavelength exceeding the above-described wavelength of 1200 nm. Other configurations are the same as those in FIG.
According to this modification, substantially the same effect as that of the second embodiment can be obtained, and the power consumption can be reduced as compared with the case of the lamp. Further, the light source device 25E can be reduced in weight and size.

(Third embodiment)
10 to 16 relate to the third embodiment of the present invention. FIG. 10 is a diagram illustrating an example of a configuration of a main part of an imaging system according to the third embodiment. FIG. 11 is a diagram illustrating an example of the relationship between the wavelength band of the irradiated light and the light transmittance in the fat and blood vessel wall. FIG. 12 is a diagram illustrating an example of an arrangement state of the light source device and the imaging device when a blood vessel traveling state is obtained using the imaging system according to the third embodiment. FIG. 13 is a diagram illustrating an example of an image visualized on the state of blood vessel running, which is displayed on a monitor when observation is performed using the imaging system according to the third embodiment. FIG. 14 is a diagram illustrating an example of the relationship between the wavelength band of irradiating light and radiance in a halogen lamp. FIG. 15 is a diagram illustrating an example of an arrangement state of the light source device and the imaging device when the blood vessel traveling state is obtained using the imaging system according to the third embodiment, which is different from FIG. FIG. 16 is a diagram showing an example of the relationship between the wavelength band of light to be irradiated and the light transmittance in fat, blood vessel wall and blood.

  As shown in FIG. 10, the imaging system 101 emits illumination light having a bandwidth in the infrared region exceeding 1200 nm to a subject 201 such as a living tissue, for example, a light source including a halogen lamp as a light source. A light source device 102 as a means and an image of the subject 201 are output, and the captured image of the subject 201 is output as an imaging signal. For example, the imaging device 103 including an endoscope or the like, the light source device 102 and the imaging device 103 The controller 106 is connected as a main part.

  The imaging device 103 captures an image of the subject 201 based on the filter 104 as a spectroscopic unit that transmits light in a predetermined wavelength band and the light transmitted through the filter 104, and outputs the image of the subject 201 as an imaging signal. And an image pickup device 105 as an image pickup means.

  The filter 104 includes a light absorption peak of the blood vessel as a predetermined wavelength band and transmits light in a band where the light transmittance of fat is equal to or higher than the light transmittance of the blood vessel wall. . In other words, the filter 104 limits the wavelength so that the imaging light used for imaging by the imaging element 105 that receives reflected or transmitted light in the illumination light emitted to the subject is only in a predetermined wavelength band. . Specifically, as shown in FIG. 11, the filter 104 has a configuration that transmits light in a band of 1200 nm to 1600 nm and light in a band of 1850 nm to 2200 nm, for example.

  The imaging element 105 is configured as an infrared detection element that is made of, for example, InGaAs, InAs, InSb, or the like and has sensitivity in an infrared region exceeding a wavelength of 1200 nm.

  The control device 106 includes a camera control unit (hereinafter abbreviated as CCU) 107 for performing control and the like on the imaging device 103, and performs video processing by performing signal processing based on the imaging signal output from the imaging device 103. A signal is generated, and the generated video signal is output to the monitor 108. Thus, the monitor 108 displays an image of the subject 201 captured by the imaging device 103 based on the video signal output from the control device 106.

  Next, the operation of the imaging system 101 will be described.

  First, in order to obtain a state of blood vessel travel at a desired observation site of a living body, for example, the user places the light source device 102 and the imaging device 103 in a positional relationship as shown in FIG. The light source device 102 is disposed at a position where the blood vessel 201a as one is illuminated, and the imaging device 103 is disposed at a position where an image of the blood vessel 201a illuminated by the illumination light emitted from the light source device 102 can be captured. .

  Thereafter, the illumination light emitted from the light source device 102 is transmitted and reflected by the blood vessel 201a, the blood 201b flowing inside the blood vessel 201a, and the fat 202 covering the periphery of the blood vessel 201a. Of the illumination light emitted from the light source device 102, the reflected light reflected by the blood vessel 201 a, the blood 201 b and the fat 202 enters the filter 104 of the imaging device 103.

  The reflected light incident on the filter 104 is emitted to the imaging element 105 as light in a state where band components other than 1200 nm to 1600 nm and 1850 nm to 2200 nm are blocked.

  The imaging element 105 captures an image of the blood vessel 201a based on the light transmitted through the filter 104, and outputs the image of the blood vessel 201a as an imaging signal.

  Thereafter, the imaging signal output from the imaging element 105 is subjected to signal processing in the control device 106 and then output to the monitor 108 as a video signal.

  As a result of the above-described operation, the monitor 108 displays an image as shown in FIG. 13 in which the state of the blood vessel running in the blood vessel 201a covered with the fat 202 is visualized. That is, an image is displayed on the monitor 108 such that the fat 202 having a high light transmittance has a relatively high luminance and the tube wall of the blood vessel 201a having a low light transmittance has a relatively low luminance. As a result, the user can perform a treatment on the living tissue while viewing the image of the living tissue that is displayed on the monitor 108 and has a clear blood vessel running state in the deep living body covered with fat or the like. In a short time.

  Further, as described above, when the transmission band of the filter 104 is set wide, the radiance is attenuated in a long wavelength band longer than the infrared band. For example, a halogen lamp having the characteristics shown in FIG. Even when used as a light source in the apparatus 102, the user can observe the state of blood vessel running in the deep part of the living body while viewing an image of brightness suitable for observation displayed on the monitor 108.

  Note that the imaging system 101 of the present embodiment may capture the blood vessel 201a with transmitted light in order to obtain substantially the same effect as described above. When the blood vessel 201a is imaged with transmitted light, the user illuminates the blood vessel 201a so that the light source device 102 and the imaging device 103 have a positional relationship as shown in FIG. The light source device 102 may be disposed at such a position, and the imaging device 103 may be disposed at a substantially opposite position across the blood vessel 201a.

  Further, in the imaging system 101 of the present embodiment, the filter 104 is not limited to that provided in the imaging device 103 as a configuration for obtaining substantially the same effect as described above. The light source device 102 may be provided so that illumination light in a band in which the light transmittance is equal to or higher than the light transmittance of the vessel wall of the blood vessel is emitted to the subject.

  By the way, as shown in FIG. 16, the light transmittance of blood is often lower than the light transmittance of fat and blood vessel walls in a band from 1200 nm to 2500 nm. Therefore, as a configuration for obtaining substantially the same effect as described above, the imaging system 1 of the present embodiment has a configuration for capturing an image based on reflected light or transmitted light in the blood 201b flowing in the blood vessel 201a. It may be a thing. Specifically, the filter 104 may have a configuration that transmits the band from 1200 nm to 2500 nm based on the light transmittance of blood described above. Further, the filter 104 having a configuration that transmits a band from 1200 nm to 2500 nm is not limited to that provided in the imaging device 103. For example, a band in which the light transmittance of fat is equal to or higher than the light transmittance of blood. The illumination light may be provided in the light source device 102 so that the illumination light is emitted toward the subject.

(Fourth embodiment)
17 to 21 relate to the fourth embodiment of the present invention. FIG. 17 is a diagram illustrating an example of a configuration of a main part of an imaging system according to the fourth embodiment. FIG. 18 is a diagram illustrating an example of a relationship between a wavelength band of light to be irradiated and light transmittance in fat, a blood vessel wall, and blood. FIG. 19 is a diagram illustrating an example of an arrangement state of the light source device and the imaging device when a blood vessel traveling state is obtained using the imaging system according to the fourth embodiment. FIG. 20 is a diagram illustrating an example of an image that visualizes the state of blood vessel running, which is displayed on a monitor when observation is performed using the imaging system according to the fourth embodiment. FIG. 21 is a diagram illustrating an example of an arrangement state of the light source device and the imaging device when the blood vessel traveling state is obtained using the imaging system according to the fourth embodiment, which is different from FIG.

  As shown in FIG. 17, the imaging system 301 emits illumination light having an infrared band exceeding at least 1200 nm to a subject 401 such as a living tissue, for example, a light source including a halogen lamp as a light source. A light source device 302 as a means and an image of the subject 401 are captured, and the captured image of the subject 401 is output as an imaging signal. For example, the imaging device 303 including an endoscope, the light source device 302, and the imaging device 303 It has a control device 306 to be connected as a main part.

  The imaging device 303 captures an image of a subject 401 based on light that has passed through the filter 304 and a filter 304 that transmits light in a predetermined wavelength band, and outputs the image of the subject 401 as an imaging signal. And an image pickup device 305 as an image pickup means.

  The filter 304 transmits light in a predetermined wavelength band including a wavelength at which the difference between the light transmittance of the fat and blood vessel wall and the light transmittance of blood is maximized, and light outside the predetermined wavelength band. It has the structure which interrupts. In other words, the filter 304 limits the wavelength so that the imaging light used for imaging by the imaging element 305 that receives reflected or transmitted light in the illumination light emitted to the subject is only in a predetermined wavelength band. . Specifically, as shown in FIG. 18, the filter 304 transmits light having at least one band among the bands of 1650 ± 50 nm, 1850 ± 50 nm, or 2200 ± 50 nm, for example. It has the structure which blocks light other than. In the present embodiment, for simplicity of explanation, it is assumed that the filter 304 has a configuration that transmits light having a band of 1650 ± 50 nm and blocks light other than the band of 1650 ± 50 nm. .

  The imaging element 305 is configured as an infrared detection element that is formed of, for example, InGaAs, InAs, InSb, and the like and has sensitivity in an infrared region exceeding a wavelength of 1200 nm.

  The control device 306 includes a camera control unit (hereinafter abbreviated as CCU) 307 for controlling the imaging device 303 and the like, and performs video processing by performing signal processing based on the imaging signal output from the imaging device 303. A signal is generated, and the generated video signal is output to the monitor 308. As a result, an image of the subject 401 imaged by the imaging device 303 based on the video signal output from the control device 306 is displayed on the monitor 308.

  Next, the operation of the imaging system 301 will be described.

  First, in order to obtain a blood vessel running state at a desired observation site of a living body, for example, the user places the light source device 302 and the imaging device 303 in a positional relationship as shown in FIG. A position where the light source device 302 is disposed at a position where the blood 401b as one of the subjects flowing inside is illuminated, and an image of the blood 401b illuminated by the illumination light emitted from the light source device 302 can be captured The imaging device 303 is disposed in the area.

  Thereafter, the illumination light emitted from the light source device 302 is transmitted and reflected by the blood vessel 401a, the blood 401b flowing inside the blood vessel 401a, and the fat 402 covering the periphery of the blood vessel 401a. Of the illumination light emitted from the light source device 302, the reflected light reflected by the blood vessel 401 a, blood 401 b, and fat 402 enters the filter 304 of the imaging device 303.

  The reflected light incident on the filter 304 is emitted to the image sensor 305 as light in a state where band components other than 1650 ± 50 nm are blocked.

  The imaging element 305 captures an image of blood 401b based on the light transmitted through the filter 304, and outputs the image of blood 401b as an imaging signal.

  Thereafter, the image signal output from the image sensor 305 is subjected to signal processing in the control device 306 and then output to the monitor 308 as a video signal.

  Due to the above-described action, the monitor 308 displays an image as shown in FIG. 20 in which the state of the blood 401b flowing inside the blood vessel 401a covered with the fat 402, that is, the state of blood vessel running is visualized. . That is, the monitor 308 displays an image in which the luminance of the blood vessel 401a and the fat 402 having a high light transmittance is relatively high and the luminance of the blood 401b having a low light transmittance is relatively low. Is done. As a result, the user can perform the treatment on the living tissue compared to the conventional case while viewing the image of the living tissue in which the blood vessel traveling state in the deep part of the living body covered with fat or the like is displayed on the monitor 308. In a short time.

  In addition, by setting the transmission band of the filter 304 in the imaging system 301 as the band as described above, the user sees an image displayed on the monitor 308 with a good contrast between fat and blood vessels and blood. However, it is possible to observe the state of blood vessel travel in the deep part of the living body.

  Note that the imaging system 301 of the present embodiment may have a configuration for imaging the blood 401b with transmitted light in order to obtain substantially the same effect as described above. When the blood 401b is imaged by transmitted light, the user illuminates the blood 401b so that the light source device 302 and the imaging device 303 have a positional relationship as shown in FIG. The light source device 302 may be disposed at such a position, and the imaging device 303 may be disposed at a position substantially opposed across the blood vessel 401a.

  In the imaging system 301 of the present embodiment, the filter 304 is not limited to that provided in the imaging device 303 as a configuration for obtaining substantially the same effect as described above. The light source device 302 may be provided so that illumination light in a band in which the difference between the light transmittance of the blood vessel wall and the light transmittance of blood is maximized is emitted to the subject. Such a configuration can be applied to any configuration in which blood 401b is imaged with reflected light and blood 401b is imaged with transmitted light.

  In addition, this invention is not limited to embodiment mentioned above, Of course, a various change and application are possible in the range which does not deviate from the meaning of invention.

1 is a diagram illustrating an overall configuration of an imaging system according to a first embodiment. The conceptual effect | action explanatory drawing of a mode that a biological tissue as a to-be-photographed object is irradiated with infrared light, and a blood vessel is observed. The figure which shows the permeability | transmittance characteristic of the blood vessel and fat in a biological tissue. The figure which shows the typical example of a image obtained by the case where the blood vessel covered with fat is observed with the light of a visible region. FIG. 3 is a diagram illustrating a schematic image example obtained by the imaging system of the first embodiment. The whole block diagram of the imaging system of the 1st modification in 1st Embodiment. The whole block diagram of the imaging system of the 2nd modification in 1st Embodiment. The whole block diagram of the imaging system concerning a 2nd embodiment. The whole block diagram of the imaging system of the modification in 2nd Embodiment. The figure which shows an example of a structure of the principal part of the imaging system which concerns on 3rd Embodiment. The figure which shows an example of the relationship between the wavelength range of the light and the light transmittance in the fat and blood vessel wall. The figure which shows an example of the arrangement | positioning state of a light source device and an imaging device at the time of imaging a blood vessel using the imaging system which concerns on 3rd Embodiment. The figure which shows an example of the image by which the state of the vascular running visualized displayed on a monitor when the blood vessel was imaged using the imaging system which concerns on 3rd Embodiment. The figure which shows an example of the relationship between the wavelength range of the light to irradiate, and radiance in a halogen lamp. The figure which shows an example different from FIG. 3 of the arrangement | positioning state of a light source device and an imaging device at the time of imaging a blood vessel using the imaging system which concerns on 3rd Embodiment. The figure which shows an example of the relationship between the wavelength range of the light and the light transmittance in fat, the blood vessel wall, and blood. The figure which shows an example of a structure of the principal part of the imaging system which concerns on 4th Embodiment. The figure which shows an example of the relationship between the wavelength range | band of the light and the light transmittance in fat, the blood vessel wall, and blood. The figure which shows an example of the arrangement | positioning state of a light source device and an imaging device at the time of obtaining the state of blood-vessel running using the imaging system which concerns on 4th Embodiment. The figure which shows an example of the image by which the state of the vascular running visualized displayed on a monitor when observing using the imaging system which concerns on 4th Embodiment. It is a figure which shows an example different from FIG. 19 of the arrangement | positioning state of a light source device and an imaging device when obtaining the state of blood-vessel running using the imaging system which concerns on 4th Embodiment.

Explanation of symbols

  1, 1B, 1C, 1D, 1E, 101, 301 ... imaging system, 2 ... living body, 2B ... abdomen, 3, 25, 25D, 25E, 102, 302 ... light source device, 4. ..Infrared camera, 5, 106, 306 ... control device, 6, 27, 108, 308 ... monitor, 11 ... lamp, 12 ... illumination lens, 13, 104,304 ... Filter, 14 ... Imaging lens, 15, 52, 105, 305 ... Image sensor, 16, 107, 307 ... CCU, 17 ... Lighting control circuit, 18, 202, 402 ... Fat 19, 201a, 401a ... blood vessel, 22 ... optical endoscope, 23, 23C, 23D ... camera head, 24, 24C ... scope, 26C ... signal processing circuit, 27a ..Image, 27b ... Color image, DESCRIPTION OF SYMBOLS 1 ... Insertion part, 32 ... Holding part, 33 ... Eyepiece part, 34 ... Light guide cable, 35 ... Light guide, 36 ... Light guide connector, 37 ... Lamp Lighting control circuit, 38... Lamp, 39... Condensing lens, 40 .. observation target part, 41 .. objective lens, 42 .. relay lens system, 43. ..Imaging lens, 47... Camera cable, 48... Image sensor drive circuit, 49, 49C... Signal processing circuit, 51... Dichroic mirror, 61. Infrared LED, 62 ... drive control circuit, 103, 303 ... imaging device, 201, 401 ... subject, 201b, 401b ... blood

Claims (10)

Light source means for generating light in the infrared region exceeding a wavelength of at least 1200 nm;
Imaging means having sensitivity in the infrared region exceeding the wavelength of 1200 nm;
A spectroscopic unit that limits the wavelength so that imaging light used for imaging by the imaging unit that receives reflected or transmitted light in the light irradiated on the subject has only a predetermined wavelength band that exceeds the wavelength of 1200 nm; ,
Comprising
The imaging system according to claim 1, wherein the predetermined wavelength band is a wavelength band including at least a light absorption peak of a blood vessel.   The spectroscopic means is constituted by filter means that transmits only the predetermined wavelength band or selective reflection means that selectively reflects light emitted from the light source means or light incident on the imaging means. The imaging system according to claim 1, wherein:   The imaging system according to claim 1, wherein the spectroscopic unit includes a light emitting element that is provided in the light source unit and emits light of the predetermined wavelength band. Light source means for generating light in the infrared region exceeding a wavelength of at least 1200 nm;
Imaging means having sensitivity in the infrared region exceeding the wavelength of 1200 nm;
A spectroscopic unit that limits the wavelength so that imaging light used for imaging by the imaging unit that receives reflected or transmitted light in the light irradiated on the subject has only a predetermined wavelength band that exceeds the wavelength of 1200 nm; ,
Comprising
The imaging system according to claim 1, wherein the predetermined wavelength band is a wavelength band including a band in which a light transmittance of a predetermined living tissue is equal to or higher than a light transmittance of a blood vessel wall or blood.   The imaging system according to claim 4, wherein the predetermined living tissue is fat.   6. The imaging system according to claim 4, wherein the predetermined wavelength band is a wavelength band including at least a band of 1200 nm to 1600 nm and a band of 1850 nm to 2200 nm.   The imaging system according to claim 4 or 5, wherein the predetermined wavelength band is a wavelength band including a band of at least 1200 nm to 2500 nm. Light source means for generating light in the infrared region exceeding a wavelength of at least 1200 nm;
Imaging means having sensitivity in the infrared region exceeding the wavelength of 1200 nm;
A spectroscopic unit that limits the wavelength so that imaging light used for imaging by the imaging unit that receives reflected or transmitted light in the light irradiated on the subject has only a predetermined wavelength band that exceeds the wavelength of 1200 nm; ,
Comprising
The imaging system according to claim 1, wherein the predetermined wavelength band is a wavelength band including a wavelength at which a difference between a light transmittance of a predetermined biological tissue and a blood vessel wall and a light transmittance of blood is a maximum.   The imaging system according to claim 8, wherein the predetermined living tissue is fat.   10. The imaging system according to claim 8, wherein the predetermined wavelength band includes at least one of a band of 1650 ± 50 nm, 1850 ± 50 nm, or 2200 ± 50 nm.

Images