JP2000041942A - Endoscope apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To observe with a higher contrast of an infrared image by dosing ICG as contrast medium. SOLUTION: An object is irradiated with infrared rays with a wavelength near 805 nm and near 930 nm from a light source unit 1 and the image of the object taken by a CCD15 is inputted into a processor 3. The processor 3 is so arranged to allot the image with the wavelength near 803 nm to a green signal and the image with the wavelength near 930 nm to a blue signal and outputs the images to a monitor 4. The infrared image with the wavelength near 805 nm absorbed more by the ICG is allotted to green greatly affecting a contrast felt by a human being thereby enabling the observation of the infrared image with a better contrast by dosing the ICG.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD OF THE INVENTION

[0002]

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

[0003]

2. Description of the Related Art In recent years, by inserting a scope into a body cavity, a gastrointestinal tract such as the esophagus, stomach, small intestine, or large intestine, or a trachea such as a lung is observed, and a treatment tool inserted into a treatment tool channel as necessary. 2. Description of the Related Art An endoscope apparatus capable of performing various kinds of medical treatments by using a computer is widely used. In particular, an endoscope apparatus using an electronic imaging device such as a charge-coupled device (CCD), that is, an electronic endoscope, can display a moving image on a color monitor in real time, and the operator who operates the endoscope is less fatigued. Widely used for.

As a monitor for an endoscope, four signals consisting of R, G, and B signals indicating a red component, a green component, and a blue component of an image and a synchronization signal are inputted, and the R, G, and B signals are converted into red, green, and blue signals. The mainstream is to display on a cathode ray tube corresponding to the dots of phosphors emitting green and blue light.

[0005] An infrared endoscope apparatus, which is an electronic endoscope using an electronic imaging device having sensitivity to near-infrared light and enabling observation of infrared light, is a main device for absorbing light in the body. Since near-infrared light, which is little absorbed by hemoglobin and water, which is a factor, is used, it is useful for imaging blood vessels in the submucosal layer, which is difficult when visible light is used. The infrared endoscope apparatus is configured to allow observation while switching between a normal image, that is, a visible image and an infrared image.

In the observation using an infrared endoscope, a method of injecting intravenously as a contrast agent a drug called indocyanine green (ICG), which has an absorption peak in blood near-infrared light having a wavelength of about 805 nm, is performed. Have been done. By intravenous injection of ICG, the blood vessel portion in the submucosal layer is shaded, and the running state of the blood vessel can be clearly observed as compared with the case where no drug is used.

In the infrared endoscope apparatus generally used conventionally, observation is performed at a single wavelength near 805 nm, and only an infrared image of a monochrome, that is, a single tone can be obtained.

For example, Japanese Patent Application Laid-Open No. Hei 6-335451 proposes a color display infrared endoscope apparatus in which images of infrared light in a plurality of wavelength bands are assigned to different color components of a monitor and displayed. In JP-A-6-335451, an image having a wavelength near 900 nm is assigned to a green component of a monitor.

[0009]

SUMMARY OF THE INVENTION However, 900
At wavelengths near nm, absorption by ICG is small, and an image at a wavelength around 900 nm, which is less absorbed by ICG, is assigned to a green component that greatly affects the sense of contrast of human beings. If the color is assigned to another color, the contrast of the infrared image at the time of ICG administration is deteriorated.

The present invention has been made in view of the above circumstances, and provides an endoscope apparatus capable of observing an infrared image at the time of ICG administration with good contrast.

[0011]

A light source for emitting light in a first wavelength band including a wavelength of 805 nm and a light in a second wavelength band not including a wavelength of 805 nm, and light emitted from the light source. Imaging means for capturing an image of the first wavelength band and an image of the second wavelength band of the subject illuminated by, and displaying the image of the first wavelength band captured by the imaging means as a green component; Display means for displaying the image of the second wavelength band as at least one color component of a red component or a blue component, so that an image of a wavelength band including a wavelength of 805 nm, which is largely absorbed by ICG, can be converted into a human image. A green component having a large influence on the sense of contrast is assigned, and an infrared image at the time of ICG administration can be observed with good contrast.

[0012]

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

(First Embodiment) FIGS. 1 to 20 relate to a first embodiment of the present invention. FIG. 1 is a block diagram for explaining the overall configuration of an endoscope apparatus, and FIG. FIG. 3 is an explanatory diagram illustrating the configuration of a visible light switching filter, FIG. 3 is an explanatory diagram illustrating light transmission characteristics of a visible light transmitting filter and an infrared light transmitting filter, FIG. 4 is an explanatory diagram illustrating the configuration of an RGB rotation filter, and FIG. FIG. 6 is an explanatory diagram illustrating the light transmission characteristics of the R filter, the G filter, and the B filter, FIG. 6 is an explanatory diagram illustrating the configuration of the CCD, FIG. 7 is an explanatory diagram illustrating the arrangement of the infrared light cut filter, and FIG. FIG. 9 is a block diagram illustrating a configuration of a color balance correction circuit, FIG. 10 is a block diagram illustrating a configuration of an image processing circuit, and FIG. 11 is a color tone adjustment circuit. Block explaining the configuration of FIGS. 12 and 13 show examples of screen display. FIG. 13 is an explanatory diagram for explaining an internal memory map of the CPU. FIG. 14 is a flowchart for explaining a flow of a filter switching process. 16 is a flowchart illustrating a flow of color tone setting, FIG. 17 is a flowchart illustrating a flow of operation of laser irradiation, FIG. 18 is a flowchart illustrating a flow of operation of image recording, and FIG. 19 is a transmission characteristic of ICG. FIG. 20 is an explanatory diagram illustrating visual spatial frequency characteristics.

As shown in FIG. 1, an endoscope apparatus according to the present embodiment includes a light source device 1 as light source means for emitting light for observation, a scope 2 for insertion into a body cavity, and a scope 2 A processor 3 for performing signal processing on the image signal obtained in step 1, a monitor 4 for displaying an image, a digital filing device 5 for recording a digital image, a photographing device 6 for recording an image as a photograph, and a laser beam for treatment. It is mainly constituted by the laser light source device 7.

The light source device 1 includes a lamp 8 such as a xenon lamp for emitting light, an infrared-visible switching filter 9 provided on an illumination optical path of the lamp 8 for limiting a transmission wavelength, and an infrared-visible switching filter 9 for switching. A motor 10, an RGB rotary filter 11, a motor 12 for rotating and driving the RGB rotary filter 11, an illumination light stop 13 for limiting an irradiation light amount, and the like are provided.

The scope 2 is a light guide fiber 14 for transmitting illumination light incident from the light source device 1 to the distal end of the scope 2, and an image pickup means C for imaging light from a subject.
A CD 15 and a scope discriminating element 19 for storing information such as the type of the scope 2 are provided.

A filter changeover switch 16 for instructing the user to switch the infrared-visible changeover filter 9 to a position where a user of an operation unit (not shown) on the scope 2 side can easily press the digital filing device 5 and the photographing device 6. A release switch 17 for instructing recording on the image recording apparatus, a laser irradiation switch 18 for instructing irradiation of treatment laser light, and the like are provided.

The processor 3 includes two pre-processing circuits 20, two A / D conversion circuits 21, two color balance correction circuits 22, a multiplexer 23, three synchronization memories 24r, 24g, 24b, an image processing circuit 25, A color tone adjustment circuit 26, three D / A conversion circuits 27r, 27g,
27b, an encoding circuit 28, a dimming circuit 29, an exposure time control circuit 30, and a CPU 31 for controlling each part of the processor 3.

A color balance setting switch 32, an image processing setting switch 33, and a color tone setting switch 34 are provided on a front panel (not shown) operated by an operator of the processor 3.

The CPU 31 can detect the state of each of the color balance setting switch 32, image processing setting switch 33, and color tone setting switch 34.

The CPU 31 can detect the state of each of the filter changeover switch 16, the release switch 17, and the laser irradiation switch 18 of the scope 2, and can read information stored in the scope discriminating element 19. It has become.

A control signal (not shown) is output from the CPU 31 to each unit of the processor 3 so as to control each unit of the processor 3. Also, CPU
An image recording instruction signal 31 is a control signal for instructing the digital filing device 5 and the photographing device 6 to record an image, and a control signal for the light source device 1 for instructing to switch the infrared-visible switching filter 9. A filter switching instruction signal and the like are output.

From the lamp 8 of the light source device 1 shown in FIG.
Light in a wavelength region including the visible region and the near-infrared region is emitted. The light emitted from the lamp 8 passes through the infrared-visible switching filter 9, the illumination light stop 13, and the RGB rotation filter 11, and is incident on the light guide fiber 14 of the scope 2.

As shown in FIG. 2, the infrared-visible switching filter 9 has two filters: a visible light transmitting filter 35 that transmits visible light, and an infrared light transmitting filter 36 that transmits infrared light. By rotating the infrared-visible switching filter 9 with the motor 10, the filter inserted on the optical path can be switched. The visible light transmitting filter 35 and the infrared light transmitting filter 36
As shown in FIG. 3, light having a wavelength in the visible region and light having a wavelength in the near infrared region are respectively transmitted.

The illumination light diaphragm 13 limits the amount of light emitted from the light source device 1 in accordance with the dimming signal output from the dimming circuit 29 of the processor 3, so that the image picked up by the CCD 15 is saturated. This is to prevent it from occurring.

As shown in FIG. 4, three filters, an R filter 37, a G filter 38, and a B filter 39, which limit the wavelength band of light to be transmitted, are arranged in the RGB rotation filter 11, By being driven to rotate, light of different wavelength bands is sequentially transmitted.

As shown in FIG. 5, the R filter 37, the G filter 38, and the B filter 39
Each of them transmits red, green, and blue light. That is, when the visible light transmitting filter 35 is inserted in the optical path, the RGB rotation filter 11
Green light and blue light are sequentially transmitted.

Further, an R filter 37, a G filter 38,
As shown in FIG. 5, the B filter 39 transmits not only light having a wavelength in the visible region but also light having a wavelength in the infrared region. The infrared light transmitting filter 36 is inserted into the optical path. 805 ± 15 nm, 805 ± 15 nm, 930 ± 2 instead of red, green and blue
Light of a wavelength band of 0 nm is transmitted.

Light guide fiber 14 of scope 2
Is radiated from the tip of the scope 2 to a subject such as a digestive tract. The light scattered and reflected by the subject enters the CCD 15 at the tip of the scope 2. CCD15 is R
Driven in synchronization with the rotation of the GB rotation filter 11, image signals corresponding to the respective irradiation lights of the R filter 37, the G filter 38, and the B filter 39 are sequentially output to the processor 3.

As shown in FIG. 6, after the charges accumulated in the CCD 15 are vertically transferred downward from the light receiving area 40, the charges of the pixels in the odd columns and the charges of the pixels in the even columns are separated by different paths. The charges are horizontally transferred, charges are converted into voltages by a charge detection unit, and output to the processor 3.

In this specification, for convenience, the path through which the image signals corresponding to the pixels in the odd-numbered columns of the CCD 15 pass is referred to as A channel, and the path through which the image signals corresponding to the pixels in the even-numbered columns pass is referred to as B channel.

That is, the A-channel image signal and the B-channel image signal are output from the CCD 15 to the processor 3.

As shown in FIG. 7, in the light receiving area 40 of the CCD 15, an infrared light cut filter 42 is arranged in an even number row (shaded area in FIG. 7) with a width corresponding to the pixel row of the CCD. I have.

As shown in FIG. 8, the infrared light cut filter 42 is an infrared light component 810 of the treatment laser light.
Light having a wavelength near nm is greatly attenuated, and light in the visible light band is almost transmitted.

Therefore, the A-channel image signal read out from the odd-numbered columns of pixels of the CCD 15 where the infrared light cut filter 42 is not disposed can include an infrared light component, and the infrared light cut filter is disposed. The image signal of the B channel read from the pixels in the even-numbered columns hardly includes the infrared light component of the treatment laser light.

The CCD 15 incorporates a so-called electronic shutter, which is means (not shown) for adjusting the charge accumulation time, and adjusts the exposure time of the image obtained by adjusting the time from sweeping out of charge to reading out. It can be adjusted.

The image signals of the two channels of the A channel and the B channel input to the processor 3 are first input to separate pre-processing circuits 20, respectively, and are subjected to CDS (correlation 2).
Processing such as double sampling) is output.

The two-system image signals output from the A-channel and B-channel pre-processing circuits 20 are converted from analog signals to digital signals by separate A / D conversion circuits 21, respectively, and are respectively subjected to different color balance corrections. Input to the circuit 22.

Each of the color balance correction circuits 22 has the same configuration, and as shown in FIG. 9, a color balance correction coefficient storage memory which is a nonvolatile memory for storing three color balance correction coefficients. 4
3r, 43g, 43b, a selector 44 for selecting a color balance correction coefficient, and a multiplier 45.

The selector 44 stores the color balance correction coefficient storage memory 43r at the timing when the R filter 37 is inserted into the optical path, the color balance correction coefficient storage memory 43g at the timing when the G filter 38 is inserted into the optical path, At the timing when the filter 39 is inserted in the optical path, the color balance correction coefficient storage memory 43b
Is to be selected.

The multiplier 45 multiplies the input image signal by the color balance correction coefficient selected by the selector 44 and outputs the result.

Each color balance correction coefficient storage memory 43
The color balance correction coefficients calculated by the CPU 31 are written in r, 43g, and 43b.

A-channel color balance correction circuit 2
2 color balance correction coefficient storage memories 43r, 43
g and 43b are configured to store a color balance correction coefficient for either the infrared image or the visible image corresponding to the switching of the infrared-visible switching filter 9, and to perform color balance correction for the B channel. A color balance correction coefficient for a visible image is always written in the color balance correction coefficient storage memories 43r, 43g, and 43b of the circuit 22.

From the image signals output from the color balance correction circuits 22, the image signals of the A channel and the B channel are alternately taken out by the multiplexer 23 in a normal state (during non-laser irradiation and visible light observation). , CC
The image is returned to the arrangement of the pixels on the light receiving area 40 of D15, and the images at the timing when the R filter 37, the G filter 38, and the B filter 39 are inserted in the optical path are sorted and stored in the synchronization memories 24r, 24g, and 24b, respectively. You.

At the time of infrared light observation, the multiplexer 23
Reads out the output signal from the color balance correction circuit 22 of the A channel at all times,
The image signals corresponding to the pixels in the even-numbered column above are interpolated by reading out the image signals of the pixels of the A channel corresponding to the same pixel twice, thereby interpolating and synchronizing the memories 24r and 24.
g, 24b.

When irradiating the laser beam, the output signal from the color balance correction circuit 22 for the B channel is read out at all times, and the image signal corresponding to the pixels in the odd columns on the light receiving area 40 of the CCD 15 is read for the B channel corresponding to the same pixel. The image signals of the pixels are interpolated by being read out twice and stored in the synchronization memories 24r, 24g, 24b.

The images stored in the synchronization memories 24r, 24g, and 24b are read out at the same time to
An image at a timing when the filter 37, the G filter 38, and the B filter 39 are sequentially inserted in the optical path, that is, a so-called plane-sequential image is synchronized.

An output signal from the A-channel color balance correction circuit 22 is input to the dimming circuit 29.

The dimming circuit 29 creates a dimming signal for keeping the brightness of the obtained image approximately constant according to the magnitude of the input image signal. The dimming signal is the light source device 1
To control the amount of light emitted from the light source device 1.

Further, the dimming circuit 29 is controlled by a control signal (not shown) from the CPU 31, and opens the illumination light diaphragm 13 at the time of irradiating the treatment laser as described later.

An output signal from the B-channel color balance correction circuit 22 is input to the exposure time control circuit 30.

The exposure time control circuit 30 controls the exposure time of the electronic shutter of the CCD 15 in accordance with the magnitude of the input image signal in order to keep the brightness of the obtained image approximately constant. Is output.

The exposure time control circuit 30 includes a CPU 3
The exposure time is controlled by a control signal (not shown) from No. 1 so that the exposure time is maximized except when the treatment laser is irradiated as described later.

As shown in FIG. 10, the image processing circuit 25 includes a dye amount calculation circuit 46, an enhancement coefficient calculation circuit 47, a delay circuit 48 for adjusting the timing of an image signal, a dye enhancement circuit 49 for performing color enhancement, and a structure enhancement. Circuit 50, monitor 4
Creation circuit 5 for creating a graph of the amount of dye to be displayed on the screen
1. It is composed of an image synthesis circuit 52.

The image processing circuit 25 includes a synchronization memory 24
Image signals synchronized at r, 24g, and 24b are input.

In this specification, for the sake of convenience, the three signals constituting the image signal at each point on the path from the synchronization memories 24r, 24g, 24b to the monitor 4 are represented by signals R,
Signal G and signal B are called. In the case of a visible image, the signals R, G, and B mean a red component signal, a green component signal, and a blue component signal of the image signal, respectively. Signals transmitted through respective cables for transmitting signals R, G, and B in the case of a visible image are also referred to as signals R, G, and B for convenience in the case of an infrared image. Further, the frame sequential images are also referred to as signals R, G, and B for convenience.

The image processing circuit 25 calculates a dye amount in a dye amount calculation circuit 46 based on the input image signal.

In accordance with the infrared-visible switching signal from the CPU 31, the dye amount calculating circuit 46 calculates a dye amount (hereinafter simply referred to as a hemoglobin amount) for the visible image for the visible image and a dye amount for the visible image. Calculates the amount of dye representing the amount of ICG (hereinafter simply referred to as the amount of ICG) for each pixel.

The magnitudes of the signals R, G, and B of the image signal input to the dye amount calculation circuit 46 are represented by Rin, Gin, and B, respectively.
Assuming that in is, the formula for calculating the hemoglobin amount IHb is expressed by IHb = log (Rin / Gin), and the formula for calculating the ICG amount IIcg is expressed by IIcg = log (Bin / Rin).

The dye amount calculating circuit 46 outputs an average dye amount, which is an average value of the dye amounts for one frame of an image, in addition to the dye amounts such as the hemoglobin amount and the ICG amount for each pixel.

The dye amount and the average dye amount calculated by the dye amount calculation circuit 46 are input to an enhancement coefficient calculation circuit 47, and an enhancement coefficient based on the difference between the dye amount and the average dye amount is calculated for each pixel. You. In the case of a visible image, the enhancement coefficient α for each pixel is represented by α = IHb−Ave (IHb), and in the case of an infrared image, I instead of IHb in the above equation
By entering Icg, the enhancement coefficient α is similarly expressed. Here, Ave (IHb) indicates the average value of one frame of the IHb image.

The dye emphasizing circuit 49 includes a delay circuit 48
The image signal, the emphasis coefficient α, and the dye enhancement level designated by the CPU 31 are adjusted in timing, and color enhancement based on the amount of dye is performed for each pixel.

The relational expression between the input signal and the output signal of the dye enhancement circuit 49 is as follows: Rout = Rin × exp (h × kR × α) Gout = Gin × exp (h × kG × α) Bout = Bin × exp (h × kB × α). However, Rin, Gin, Bin are the dye emphasis circuit 4.
9, Rout, Gout, and Bout represent the magnitudes of the signals R, G, and B of the image signal input to the dye enhancement circuit 4, respectively.
9 is the magnitude of each of the signals R, G, and B of the image signal output from FIG. Further, kR, kG, and kB are coefficients determined by the absorptance of each target dye for each color, and these take different values between a visible image and an infrared image.
The values of kR, kG, and kB are switched between a value for a visible image and a value for an infrared image according to an infrared-visible switching signal from the CPU 31. H is a coefficient indicating the degree of emphasis, and is determined by the dye emphasis level set by the CPU 31. Α is an enhancement coefficient.

By performing color enhancement in the dye enhancement circuit 49, an image is formed in which the apparent hemoglobin amount IHb is increased at the time of enhancement based on the hemoglobin amount IHb, and at the time of enhancement based on the ICG amount IIcg.
An image is formed such that the CG amount IIcg increases.

Further, by emphasizing the image signal with the emphasis coefficient α, which is the difference between the dye amount calculated by the emphasis coefficient calculating circuit 47 and the average dye amount, it is possible to effectively emphasize even an image having a biased color distribution. I can do it.

The image signal output from the dye emphasizing circuit 49 is emphasized by a spatial filter by a structure emphasizing circuit 50 so as to emphasize a fine pattern on a living mucous membrane. The degree of the structure emphasis in the structure emphasis circuit 50 is determined by the CPU 3.
It is determined by the structure enhancement level output from 1.

The average dye amount calculated by the dye amount calculation circuit 46 is also input to the graph creation circuit 51. The graph creation circuit 51 determines whether the input dye amount is the hemoglobin amount IHb or the ICG amount IIcg with reference to the infrared-visible switching signal from the CPU 31, and the horizontal axis represents time, and the vertical axis represents time. At this time, an image signal displaying a graph with the average dye amount input is output.

In the image synthesizing circuit 52, the structure emphasizing circuit 50
The image signal output from the graph creation circuit 51 is superimposed on the image signal output from. The output signal of the image synthesis circuit 52 becomes the output signal of the image processing circuit 25.

As shown in FIG. 11, the tone adjustment circuit 26 has three tone adjustment coefficient storage memories 53r, 53g, 53 which are nonvolatile memories for storing tone adjustment coefficients.
b, three multipliers 54r, 54g, 54b and three gamma correction circuits 55r, 55g, 55b.

The color tone adjustment circuit 26 includes an image processing circuit 25
Is input.

Each tone adjustment coefficient storage memory 53r, 53
g and 53b are color tone adjustment coefficients corresponding to the signals R, G and B of the input image signal of the color tone adjustment circuit 26, respectively.
It is written by U31.

The signals R, G, and B of the input image signal are obtained by combining the tone adjustment coefficients stored in the tone adjustment coefficient storage memories 53r, 53g, and 53b with the multipliers 54r, 54g, and 5b.
4b, and are converted into a color tone set by the user.

Each signal output from the multipliers 54r, 54g, 54b is subjected to gamma correction, that is, conversion for correcting the gamma characteristic of the monitor 4, by gamma correction circuits 55r, 55g, respectively.
g, 55b and output.

The signals R, G, and B of the image signal output from the color tone adjustment circuit 26 are respectively converted into D / A conversion circuits 27r,
The signals are converted into analog signals at 27g and 27b and output to the monitor 4, and the image of the subject is displayed on the monitor 4. The image signal encoded by the encoding circuit 28 is sent to the digital filing device 5 and the photographing device 6,
In accordance with an image recording instruction signal from the CPU 31, an image is recorded in each device.

FIG. 12 is an example of a screen display on the monitor 4 when an infrared image is displayed. An infrared image is displayed in the octagon on the right side of the screen, and a character string “IR Observation” indicating that the image being displayed is an infrared image is displayed on the lower right of the screen. In addition, a graph in which the horizontal axis represents time and the vertical axis represents ICG amount (average dye amount) is displayed at the lower left of the image. From this graph, the time change of the ICG amount can be quantitatively known, and the degree of decrease in the ICG amount with respect to the elapsed time after ICG administration can be quantitatively known. I
CG is selectively taken up by the liver when injected intravenously, and the state of liver function can be known from the uptake rate. Therefore, the liver function can be checked by quantitatively knowing how the ICG amount has decreased with respect to the elapsed time.

The CPU 31 has a nonvolatile memory area therein, and stores set values such as various coefficients used in the color balance correction circuit 22, the image processing circuit 25, and the color tone adjustment circuit 26.

FIG. 13 shows a part of the internal memory map of the CPU 31.

As the color balance correction coefficient, a value is stored when the user sets the color balance according to a procedure described later.

The values of the dye enhancement level, the structure enhancement level, and the color tone adjustment level are updated each time the user changes the set value (set level) by operating the front panel.

The tone adjustment coefficient is a value stored in the CPU 31 in advance, and when the user changes the tone adjustment level, the tone adjustment coefficient corresponding to the set level is output to the tone adjustment circuit 26. .

As described above, the internal memory of the CPU 31
It has a role as a storage unit for the color balance correction amount, color tone adjustment value, and image processing set value.

Further, the CPU 31 outputs an instruction signal for switching the filter and setting various set values during the vertical blanking period so that the image is not disturbed. The CPU 31 can determine whether the connected scope is an infrared scope by reading information stored in the scope determination element 19 incorporated in the scope 2. The infrared scope described here is shown in FIG.
The infrared cut filter 42 is partially disposed on the front surface of the light receiving surface 40 of the CCD 15 as shown in FIG.
In addition, a scope that does not support infrared is a scope in which an infrared cut filter is arranged on the entire light receiving surface of the CCD and is not suitable for infrared light observation.

When the filter changeover switch 16 is pressed,
A filter switching request signal is sent. When detecting the filter switching request signal, the CPU 31 executes processing according to the flowchart shown in FIG. Note that reference numerals S1 to S11 are reference numerals assigned to the processing steps.

First, in step S1, it is determined whether or not the currently connected scope 2 is an infrared scope. If the scope 2 is a scope that does not support infrared, the processing is performed without any operation. finish.

In step S1, if the currently connected scope 2 is an infrared scope, as shown in step S2, a filter switching instruction signal is sent to the light source device 1, and the visible light transmitting filter 35 The light transmission filter 36 or the infrared light transmission filter 36 is switched to the visible light transmission filter 35.

Next, in step S3, the filter inserted in the optical path at this time is the infrared light transmitting filter 3.
6 or visible light transmission filter 35,
In the case of the infrared light transmitting filter 36, as shown in step S4, the infrared color balance correction coefficient is written in the color balance correction coefficient storage memory 43 of the color balance correction circuit 22 for the A channel, and as shown in step S5, An infrared image enhancement level (a dye enhancement level and a structure enhancement level) and an infrared-visible switching signal are sent to the image processing circuit 25, and the infrared color tone adjustment coefficient is written into the color tone adjustment coefficient storage memory 54 as shown in step S6. Step S7
As shown in (5), the signal of channel A is always selected by the multiplexer 23, and the process is terminated.

Since the signal of the A channel is a signal of a pixel transmitting infrared light, an infrared image of a subject can be taken well. However, since the signals of the same pixel are arranged in two pixels in the horizontal direction, the resolution in the horizontal direction is deteriorated as compared with a normal image.

If it is determined in step S3 that the visible light transmitting filter 35 is inserted in the optical path, the visible light color balance correction coefficient storage memory 43 stores the visible light color balance as shown in step S8. The correction coefficient is written, the visible image enhancement level and the infrared-visible switching signal are sent to the image processing circuit 25 as shown in step S9, and the visible color adjustment coefficient is stored in the color adjustment coefficient storage memory 54 as shown in step S10. Is written, and as shown in step S11, the multiplexer 23
Is set so that the signal of the A channel and the signal of the B channel are alternately input for each pixel, and the process is terminated.

The filter switching process allows the CPU 31
Reads the various set values from the internal memory and switches them according to the switching between the visible light transmitting filter 35 and the infrared light transmitting filter 36, so that the user can observe the desired image without any troublesome operation. Can be.

By switching the multiplexer 23,
At the time of visible light observation, a high-resolution image using all the pixels of the CCD can be obtained.
A bright infrared image is obtained using pixels in which No. 2 is not arranged.

When setting the color balance, the user takes an image of the reference color object and sets the color balance setting switch 3 on the front panel of the processor 3.
Press 2. The reference color object here is visible light to 1000 n.
The reflectance is defined at a near-infrared wavelength of about m, and the object is a color reference. When the color balance setting switch 32 is pressed, a color balance setting request signal is sent to the CPU 31. When the color balance setting request signal is sent, the CPU 31 performs processing according to the flowchart shown in FIG. In addition, the symbols S12 to S12
21 is a reference number assigned to the processing step.

First, in step S12, if the infrared light transmitting filter 36 is in the state of being inserted in the optical path,
As shown in step S13, the filter switching process (FIG. 4)
), And the visible light transmitting filter 35 is inserted into the optical path.

Next, as shown in step S14, the CP
U31 takes in the visible image signals of the A channel and the B channel after the A / D conversion.

Next, as shown in step S15, the signals R, G, B of the A channel and the B channel, respectively.
The color balance correction for the visible channel for the A channel and the B channel is performed so that the brightness ratio of each image becomes a predetermined value and the variation such as the amplification factor between the A channel and the B channel is corrected. Calculate the respective coefficients and calculate C
It is stored in the internal memory of the PU 31.

Next, as shown in step S16, the color balance correction coefficients calculated in step 15 are stored in the color balance correction coefficient storage memories 43r, 43g, and 43b.

Next, in step S17, the connected scope 2 is determined, and if the scope 2 is not an infrared scope, the process is terminated.

If the connected scope 2 is an infrared scope in step S17, first, as shown in step S18, a filter switching process (FIG. 14) is performed.
), And the filter inserted into the optical path is switched to the infrared light transmitting filter 36.

Next, as shown in step S19, an infrared image of the A channel is taken into the CPU 31.

Next, as shown in step S20, the ratio of the brightness of each infrared image captured at the timing when each of the R filter 37, the G filter 38, and the B filter 39 is inserted into the optical path is set to a predetermined value. The infrared color balance correction coefficient for the A channel is calculated so that
In the internal memory.

Next, as shown in step S21, a filter switching process (see FIG. 14) is performed to switch to a visible image.

As described above, only by pressing the color balance setting switch 32, the setting of the color balance correction for visible light and the setting of color balance correction for infrared can be easily performed.

When the user changes the color tone level by using the color tone setting switch 34, a color tone setting request signal is sent to the CPU 31. The color tone setting request signal includes signals R,
Information indicating which level of G or B is to be set is included. When detecting the color tone setting request signal, the CPU 31 executes processing according to the flowchart shown in FIG. Note that reference numerals S22 to S26 are reference numerals assigned to the processing steps.

First, in step S22, if the infrared light transmitting filter 36 is in the state of being inserted in the optical path,
As shown in step S23, the changed set value is stored as an infrared color tone adjustment level in the internal memory of the CPU 31, and as shown in step S24, the signals R, G, and B for the signals R, G, and B corresponding to the changed level are stored. Are stored in the color tone adjustment coefficient storage memories 53r, 53, g, and 53b, respectively.
And the process ends.

If it is determined in step S22 that the visible light transmitting filter 35 is inserted in the optical path,
As shown in step S25, the input set value is stored in the internal memory of the CPU 31 as a color tone adjustment level for visible light, and as shown in step S26, each color of the signals R, G, and B corresponding to the changed level Color adjustment coefficients are stored in memory 53r, 53g, and 53b, respectively.
And the process ends.

As described above, the color tone setting switch 34 is set to 1
One switch also serves as a switch for the visible image and a switch for the infrared image, and changes the color tone adjustment level corresponding to the filter inserted at that time.

When the user changes the set value of image processing (image enhancement level) with the image processing setting switch 33, an image processing setting request signal is sent to the CPU 31.
When the CPU 31 receives the image processing setting request signal,
Similarly to the case of changing the color tone level, the changed infrared or visible image enhancement level (dye enhancement level, structure enhancement level) is stored in the internal memory of the CPU 31, and the changed enhancement level is stored in the image processing circuit. send. in this way,
The image processing setting switch 33 also serves as a switch for the visible image and a switch for the infrared image with one switch, and changes the image enhancement level corresponding to the filter inserted at that time.

When the laser irradiation switch 18 is pressed,
A laser irradiation request signal is sent to the CPU 31. C
When the PU 31 detects the laser irradiation request signal,
The processing is executed according to the flowchart shown in FIG.
Note that reference numerals S27 to S37 are reference numerals assigned to the processing steps.

First, in step S27, it is determined whether the filter inserted in the optical path is the visible light transmitting filter 35 or the infrared light transmitting filter 36. If the filter is the infrared transmitting filter 36, the process proceeds to step S38. As shown in (5), a warning message is displayed on the monitor 4, and the process is terminated.

This is because when irradiating a laser while performing infrared observation, halation occurs in an image and operability is impaired.

If it is determined in step S27 that the visible light transmitting filter 35 is inserted in the optical path, the process proceeds to step S2.
At 8, it is determined whether or not the connected scope 2 is an infrared scope.

In step S28, if the scope 2 is not an infrared scope, the process proceeds to step 32 for starting laser beam irradiation without performing the processing shown in steps S29 to S31.

When the scope 2 is an infrared scope in step S28, as shown in step S29,
The signal of the B channel is input by the multiplexer 23, and as shown in step S30, a control signal (not shown) is sent to the dimming circuit 29, the illumination light aperture 13 is opened, and the maximum amount of light is Then, as shown in step S31, a control signal (not shown) is sent to the exposure time control circuit 30 so that an image with appropriate brightness can be obtained by the electronic shutter.

Next, as shown in step S32, a laser irradiation start instruction signal for instructing laser irradiation to the laser light source device 7 is sent, and the laser light source device 7 starts irradiation of laser light.

Next, as shown in step S33, the process waits until the laser irradiation switch 18 is released.

In step S33, when the laser irradiation switch 18 is released, a laser light irradiation stop instruction signal for instructing the laser light source device 7 to stop laser light irradiation is sent to the laser light source device 7 as shown in step S34. Stops laser light irradiation.

Next, as shown in step S35, the CP
U31 starts the dimming by the dimming circuit 29, and proceeds to Step S
As shown at 36, the exposure time control circuit 30 sends a control signal so that the exposure time becomes the maximum.

Next, as shown in step S37, the input by the multiplexer 23 is controlled so as to be an alternate input of the A channel and the B channel, and the processing is terminated.

As described above, when the light control and the electronic shutter are combined, when the laser light is not irradiated, the influence on the living body can be suppressed by maximizing the exposure time and minimizing the amount of light from the light source device. When irradiating a laser beam, by controlling the brightness with an electronic shutter by maximizing the light amount of the light source device, the influence of the laser beam on the image is relatively reduced, and halation can be suppressed.

Further, by switching the multiplexer 23,
At the time of non-irradiation of laser light, a high-resolution image using all the pixels of the CCD is obtained. At the time of laser light irradiation, an image with little halation is obtained by the laser light using the pixel where the infrared light cut filter 42 is arranged. Can be

When the release switch 17 is pressed, the CP
An image recording request signal is sent to U31. CPU31
Executes the processing according to the flowchart shown in FIG. 18 upon detecting the image recording request signal. Note that reference numerals S39 to S43 are reference numerals assigned to the processing steps.

First, as shown in step S39, an image recording instruction signal is sent to each image recording device, that is, the digital filing device 5 and the photographing device 6.

Thus, each image recording device records an image according to the instruction of the image recording instruction signal.

The digital filing device 5 communicates with the processor 3 to communicate with the patient data, the type of scope,
It also receives information such as the type of the inserted filter, the set values of image processing and color tone adjustment, and records the information together with the image as header information of the image.

Next, in step S40, it is determined whether or not the connected scope 2 is an infrared scope. If not, the process is terminated.

In step S40, if the scope 2 is an infrared scope, a filter switching process (see FIG. 14) is performed as shown in step 41, and an image recording instruction is issued again to each image recording device as shown in step S42. The signal is sent, and as shown in step S43, the filter switching process is performed again to return to the original filter, and the process ends.

By such processing, the user can record both the visible image and the infrared image by pressing the release switch 17 once.

In the present embodiment, a wavelength of 805 nm is displayed as a red component and a green component, and a wavelength of 930 nm is displayed as a blue component on the monitor 4 during infrared light observation. I
The transmission characteristics of the CG are as shown in the graph of FIG. The horizontal axis of this graph represents the wavelength, and the vertical axis represents the transmittance. In this graph, the curve marked “ICG” is the characteristic of ICG, the curve marked “HS” is the characteristic of the serum of the human body, and “ICG + H”.
The curve labeled "S" is the combined properties of ICG and human serum.

In this graph, the curve marked “ICG” indicates that the transmittance is lowest at a wavelength slightly shorter than 800 nm, and that at this wavelength, light absorption by ICG alone is large. ing.

[0129] ICG alone has the lowest transmittance at a wavelength slightly shorter than 800 nm, but ICG administered in a living body has an "ICG" due to the effect of protein binding.
+ HS ”, the wavelength at which the transmittance is lowest slightly shifts to the longer wavelength side, and the effective maximum absorption wavelength of ICG at a wavelength in the visible or near infrared region is around 805 nm. Becomes

At wavelengths around 930 nm, the wavelengths shown in FIG.
As shown in the graph, light absorption by ICG is small.

Therefore, when ICG is injected intravenously into a subject, an image having a wavelength of 805 nm becomes an image with high contrast because light is absorbed by the ICG and blood vessels are darkened. On the other hand, in the image having a wavelength of 930 nm, light is not so much absorbed by the ICG, the blood vessel portion is not so dark, and the contrast is low.

Since the wavelength of 805 nm is assigned to the green and red components of the monitor 4 and the wavelength of 930 nm is assigned to the blue component of the monitor 4,
Above, an image in which the blood vessel part is stained blue is observed.

Here, it is important to assign the 805 nm image to the green component and the red component of the monitor 4 in order to obtain an image with a high contrast. this is,
Due to human visual characteristics.

FIG. 20 is a graph showing visual spatial frequency characteristics, in which the horizontal axis represents spatial frequency and the vertical axis represents relative contrast sensitivity. In the figure, a curve marked “(y−b)” is a relative contrast sensitivity to a stripe pattern generated by a color difference between yellow and blue, and a curve marked “(r−g)” is a red mark. Contrast sensitivity to a stripe pattern generated by the color difference between green and green, "Br (bright and dark)"
The curve marked “” indicates the relative contrast sensitivity known from the stripe pattern caused by light and dark.

From this graph, it can be seen that higher spatial frequencies can be recognized when there is light and darkness than when only the hue changes. That is, human eyes cannot see a fine structure only by a change in hue, and a change in luminance is necessary in an image to see a fine structure such as a blood vessel structure. Among the red component, the green component, and the blue component, the effect on the luminance is largest for the green component and smallest for the blue component.

Therefore, in order to display a fine structure with good contrast on the monitor 4 which is a color monitor, it is effective to assign an image of a target dye, that is, an image of a wavelength at which light is largely absorbed by ICG, to the green component of the monitor 4. It is.

When an image having a wavelength at which light is largely absorbed by the target dye, ie, ICG, is also assigned to the red component of the monitor 4, the color component, for example, the blue component is left at the position where the light is absorbed by the ICG, while the contrast is maintained. A high-quality image can be obtained.

The reason that a normal endoscopic image, that is, a visible image, can observe a relatively fine portion of a blood vessel part with good contrast is that hemoglobin which is a dye in a living body absorbs a large amount of light of blue and green wavelengths. This is because the change in luminance of the obtained image is relatively large.

The characteristics of ICG are as shown in FIG. 19, and the ICG derivative-labeled antibody also shows light absorption characteristics similar to ICG. Therefore, by observing the subject to which the ICG derivative-labeled antibody has been sprayed in advance with infrared light, the lesion where the ICG derivative-labeled antibody has accumulated can be recognized as a blue stain on the monitor 4 as in the case where ICG was administered. Can be.

In the present embodiment, attention is paid to the light absorption characteristics of ICG or an ICG derivative-labeled antibody, and light having a wavelength around 805 nm, which is the maximum absorption peak in the body, of the ICG or ICG derivative-labeled antibody is compared with light having a relatively high absorption rate The location of ICG or an ICG derivative-labeled antibody, which is observed using light having a low wavelength of around 930 nm, can be effectively observed by observing the color of an endoscopic image. Therefore, it is not necessary to use an expensive high-sensitivity element, the cost can be suppressed, and the accumulation of ICG or an ICG derivative-labeled antibody can be confirmed, and the presence or absence of a lesion can be confirmed.

In this embodiment, the present invention is applied to the frame sequential endoscope apparatus. However, the present embodiment is applied to the case where the mosaic filter of the simultaneous endoscope apparatus has infrared transmission characteristics. The same effect can be obtained.

The technique of changing various set values in accordance with the switching of the filter is not limited to switching between infrared light and visible light, but may be applied to light including infrared light, visible light, ultraviolet light, fluorescence, or the like. It may be applied to switching, or may be applied to switching of plural types of visible light having different characteristics.

When the filter is switched, in order to recognize the type of the filter currently inserted in the optical path,
An infrared image or a visible image may be automatically recognized based on the image quality of the image.

Also, instead of the color tone adjustment circuit 26, CP
In U31, the color balance correction coefficient is multiplied by the color tone adjustment coefficient, and the product is stored in the color balance correction coefficient storage memory.
Therefore, the color may be adjusted and the cost may be reduced.

In the dye amount calculating circuit 46 of the image processing circuit 25, when the infrared light transmitting filter 36 is inserted, the ICG
The brightness of the image may be obtained instead of the amount, and the contrast may be converted by the dye emphasizing circuit 49 based on the average brightness of the image, so that the contrast of the infrared image may be adjusted and observed.

Further, the image processing circuit 25 is not limited to the one incorporated in the processor 3 as in the present embodiment, but may be an external device. In this case, the image signal and the control signal are transmitted via a cable. You may.

It is convenient to allow the user to set whether or not to display the graph indicating the amount of dye.

Also, a luminance signal and a chrominance signal may be generated from the signals R, G, and B during the processing, and the image signal may be output from the processor 3 as a composite signal and input to the monitor 4.

The monitor 4 to be displayed is not limited to the CRT type, and a plasma display or a liquid crystal display may be used.

Further, communication is performed between the CPU 31 of the processor 3 and the light source device 1 to determine whether or not the light source is compatible with infrared observation, which is the same as the infrared scove determination in the present embodiment. Branch processing may be performed.

Further, a filter changeover switch 16 is provided on the front panel of the light source device 1 and communication is performed between the light source device 1 and the CPU 31 of the processor 3 to request a filter changeover. Processing may be performed.

The antibody of the ICG derivative-labeled antibody is not limited to the antibody targeting the cancer such as the CEA antibody. For example, by using an antibody targeting the Helicobacter pylori, the antibody may be used for diagnosis of the presence of Helicobacter pylori. Good.

The effects of the present embodiment described above are as follows.

A light source device 1 having a lamp 8 as light source means for emitting light in a first wavelength band including a wavelength of 805 nm and light in a second wavelength band including a wavelength of 930 nm not including the wavelength of 805 nm; The first wavelength band of the object illuminated by the light emitted from the light source means, ie, 8
A CCD 15 serving as an imaging unit for capturing an image of a wavelength band including 05 nm and an image of a second wavelength band, ie, an image of a wavelength band including 930 nm, and the first wavelength band captured by the imaging unit, ie, a wavelength band including 805 nm. Is displayed as a green component, and the second wavelength band, ie, 930
a monitor 4 which is a display unit connected to the processor 3 which performs signal processing so as to display an image in a wavelength band including nm as at least one of a red component and a blue component.
And 805, which is largely absorbed by ICG
The image in the wavelength band including the wavelength of nm is assigned to the green component that has a large effect on the human sense of contrast.
This makes it possible to observe an infrared image at the time of administration with good contrast.

In addition, since the display means for displaying the image in the wavelength band including 930 nm as the red component or the blue component of the display means is provided, it is possible to clearly distinguish the high and low ICG density parts by color.

Further, since the display means for displaying the image in the wavelength band including 805 nm on both the green component and the red component of the display means is provided, the sense of contrast of the displayed image is greatly increased.

The image picked up using the visible light transmitting filter 35 as the first wavelength limiting means is different from the image picked up using the infrared light transmitting filter 36 as the second wavelength limiting means. Since the color balance is corrected using the color balance correction coefficient, the color balance is properly corrected when either of the wavelength limiting means is used.

In addition, one instruction from the color balance setting instructing means, one for the visible light transmitting filter 35 as the first wavelength limiting means and the other for the infrared light transmitting filter 36 as the second wavelength limiting means. Since two color balance correction amounts are obtained, the color balance can be easily set.

The image picked up using the visible light transmitting filter 35 as the first wavelength limiting means is different from the image picked up using the infrared light transmitting filter 36 as the second wavelength limiting means. Since the color tone is adjusted using the color tone adjustment coefficient, the color tone is appropriately adjusted when either of the wavelength limiting means is used.

In addition, an image captured using the visible light transmitting filter 35 as the first wavelength limiting means and an image captured using the infrared light transmitting filter 36 as the second wavelength limiting means are: Since the image processing is performed using different set values, the image processing is appropriately performed when either of the wavelength limiting units is used.

Also, with one instruction from the image recording instruction means, the visible light transmitting filter 35 serving as the first wavelength limiting means can be used.
And both the image captured using the infrared light transmission filter 36 as the second wavelength limiting means and the image captured using the second wavelength limiting means are recorded. Can be recorded with simple operation.

Further, since the dye amount calculating circuit 46 for obtaining the dye amount of the subject is provided and the time change of the calculated dye amount is displayed, the change in the dye amount can be notified quantitatively.

Further, the infrared light cut filter 42 which is a wavelength limiting means for partially covering the light receiving area 40 which is the light receiving surface of the CCD 15 which is the image pickup means and removing the laser light is provided. Without receiving
An image with less halation is created.

The amount of light of the light source is increased in accordance with an instruction to irradiate the treatment laser light to the subject, and the CCD 1 serving as an image pickup means is increased.
Since the exposure time of No. 5 is shortened, the influence of the treatment laser beam on the image is reduced.

A wavelength limiting means for guiding light having a wavelength including 805 nm which is a substantial absorption peak wavelength of a drug such as ICG, for example, a G filter 38 and guiding light having a wavelength including 930 nm which does not include 805 nm. Since, for example, the B filter 39 serving as the wavelength limiting means is provided, the degree of accumulation of a drug such as ICG can be easily known from the obtained image.

(Second Embodiment) FIGS. 21 to 22
FIG. 21 is a diagram illustrating light transmission characteristics of an R filter, a G filter, and a B filter, and FIG. 22 is a diagram illustrating states and operations of a visible-infrared switching filter and an RGB rotation filter. FIG. 4 is an explanatory diagram for explaining a relationship with a synchronization memory.

The configuration and operation of the parts not described in the present embodiment are the same as the configuration and operation of the parts described in the first embodiment.

The R filter 37, the G filter 38, and the B filter 39 of this embodiment correspond to “R”,
It has transmission characteristics indicated by curves marked “G” and “B”.

The visible light transmitting filter 3 is added to the R filter 37, the G filter 38, and the B filter 39 according to the present embodiment.
5 are the same as those of the first embodiment, but when the infrared light transmitting filter 36 is combined, the R filter 37 is 805 ± 15 nm, and the G filter 38 is 930 ± 20 nm. At a wavelength of

FIG. 22 shows which of the three synchronization memories 24r, 24g, and 24b stores the image signal in synchronization with the switching of the infrared-visible switching filter 9 and the rotation of the RGB rotation filter 11. Are shown.

In the multiplexer 23, when the visible light transmitting filter 35 is inserted, the image when the R filter 37 is inserted is synchronized with the synchronization memory 24r as in the first embodiment.
Then, the image when the G filter 38 is inserted is stored in the synchronization memory 24g, and the image when the B filter 39 is inserted is stored in the synchronization memory 24b. However, when the infrared light transmitting filter 36 is inserted, the image when the R filter 37 is inserted is stored in the synchronization memory 24r and the synchronization memory 24g.
Then, the image when the G filter 38 is inserted is stored in the synchronization memory 24b.

Since the infrared image obtained in this embodiment has the same color tone as that of the first embodiment, the wavelength of 805 nm is displayed as the red component and the green component of the monitor 4 and the wavelength of 930 nm is displayed as the blue component. Is done. Therefore, as in the first embodiment, the same effects as in the first embodiment can be obtained in the present embodiment, for example, ICG or an ICG derivative-labeled antibody can be observed with good contrast.

The R filter 3 used in the present embodiment
7, the G filter 38 and the B filter 29 require a relatively small number of rising edges and falling edges, so that only a small number of interference films are deposited on the filters.
A filter can be created at low cost.

(Third Embodiment) FIGS. 23 to 26
FIG. 23 relates to a third embodiment of the present invention, and FIG. 23 shows light transmission characteristics of a visible light transmission filter and an infrared light transmission filter.
4 is a light transmission characteristic of an R filter, a G filter, and a B filter, FIG. 25 is a block diagram illustrating a configuration of an extension multiplexer, and FIG. 26 is an explanatory diagram illustrating a light absorption characteristic of hemoglobin. The configuration and operation of the parts that do not exist are the same as the configuration and operation of the parts described in the first embodiment.

Infrared / visible switching filter 9 of the present embodiment
Indicates the transmission characteristics shown in FIG. 23. The infrared light transmission filter 36 transmits not only infrared light but also light in a wavelength region corresponding to blue visible light. The RGB rotation filter 11 has the transmission characteristics shown in FIG. 24, and the B filter 39 does not transmit at least a wavelength of 1000 nm or less in near-infrared light. Further, the synchronization memory 24 according to the first embodiment
r, 24g, 24b and the image processing circuit 25, FIG.
An extension multiplexer 56 shown in FIG.

In this embodiment, the transmission characteristics when the R filter 37, the G filter 38, and the B filter 39 are respectively combined with the visible light transmission filter 35 are the same as those of the first embodiment, When combined with the light transmission filter 36, the R filter 37 transmits a wavelength range of 805 ± 15 nm, the G filter 38 transmits a wavelength range of 930 ± 20 nm, and the B filter 39 transmits a blue wavelength range of visible light.

The average value calculation circuit 57 of the extension multiplexer 56 calculates the average value of the image signal when the R filter 37 is inserted and when the B filter 39 is inserted for each pixel. The two selectors 58 and 59 are switched in synchronization with the switching of the infrared-visible switching filter 9 by a control signal (not shown) from the CPU 31. When the visible light transmitting filter 35 is inserted, the selector 58 selects the signal G of the input image signal, and the selector 59 selects the signal B of the input image signal. Accordingly, the input image signals R, G, and B of the input image are output as signals R, G, and B of the output image signal, respectively. When the infrared light transmitting filter 36 is inserted, the selector 58 selects the output from the average value calculation circuit 57, and the selector 59 selects the signal G of the input image signal. Therefore, the signal R of the input image signal is output as it is as the signal R of the output image signal, but the signal G of the output image signal is an average of the signal R of the input image signal and the signal B of the input image signal. The value is output, and the signal G of the input image signal is output as the signal B of the output image signal. The infrared image finally displayed on the monitor 4 is 805 as the red component of the monitor 4.
An image with a wavelength of ± 15 nm is 805 ± 1 as a green component.
An image having an average value of 5 nm and a blue wavelength and an image having a wavelength of 930 ± 20 nm as a blue component are displayed.

Hemoglobin has light absorption characteristics as shown in FIG. The curve labeled “Hb” in the figure represents the characteristics of hemoglobin not bound to oxygen, and “HbO”
The curve marked `` 2 '' shows the properties of hemoglobin bound to oxygen, but both are in the visible light wavelength range.
It is a dye that exhibits large absorption in the wavelength region of 380 to 590 nm, that is, in the wavelength region from blue to green.

In this embodiment, when observing an infrared image,
As the green component of the monitor 4, an image of a wavelength around 805 nm where light absorption by ICG or ICG derivative-labeled antibody is large and an image of a blue wavelength band where absorption by hemoglobin is large are displayed. In addition to the thick blood vessels, fine blood vessels on the mucosal surface that can be observed with blue light can be simultaneously observed with good contrast.

The present invention is not limited to the above-described embodiment, but can be variously modified without departing from the gist of the invention.

[Appendix] (Appendix 1) Light source means for emitting light in a first wavelength band including a wavelength of 805 nm and light in a second wavelength band not including a wavelength of 805 nm, and light emitted from the light source means. The image of the subject in the first wavelength band and the second
Imaging means for capturing an image of the wavelength band of the first wavelength band, the image of the first wavelength band captured by the imaging means is displayed as a green component, and the image of the second wavelength band is at least a red component or a blue component. An endoscope apparatus comprising: a display unit for displaying one color component.

(Additional Item 2) The second wavelength band is 93
2. The endoscope apparatus according to claim 1, wherein the endoscope apparatus has a wavelength band including a wavelength of 0 nm.

(Additional Item 3) The endoscope apparatus according to additional items 1 and 2, wherein the display means displays an image of the first wavelength band as a red component.

(Additional Item 4) The display means is 380 nm
4. The endoscope apparatus according to claim 1, wherein an image of at least a part of the wavelength band of 590 nm to 590 nm and the image of the first wavelength band are displayed as a green component.

(Additional Item 5) Light source means for emitting light, image pickup means for picking up an image of a subject illuminated by the light source means, and light source inserted on an optical path between the light source means and the image pickup means. A first wavelength limiter and a second wavelength limiter, which are two wavelength limiters selectively used to limit a transmission wavelength, and a signal magnitude of each color component of an image taken by the imager. Color balance correction means for correcting the color balance by multiplying by a color balance correction coefficient which is a coefficient for correcting the color balance, and imaging by the imaging means when using the first wavelength limiting means. A first correction coefficient storage unit for storing a first color balance correction coefficient used for correcting the color balance of the image of the subject, and a method for using the second wavelength limiting unit. A second correction coefficient storing means for storing a second color balance correction coefficient used to correct the color balance of the image of the imaged object by the image pickup means,
An endoscope apparatus comprising:

(Additional Item 6) A reference color object having a reference color, color balance setting instructing means for instructing to calculate the color balance correction coefficient, and one time from the color balance setting instructing means. In response to the instruction, an image of the reference color object is taken in a state where the first wavelength limiting unit is used, the first color balance correction coefficient is calculated, and the second wavelength limiting unit is used. 6. An endoscope apparatus according to claim 5, further comprising: control means for capturing an image of the reference color object and obtaining the second color balance correction amount.

(Additional Item 7) Light source means for emitting light, image pickup means for picking up an image of a subject illuminated by the light source means, and light source inserted on an optical path between the light source means and the image pickup means. A first wavelength limiter and a second wavelength limiter, which are two wavelength limiters selectively used to limit a transmission wavelength, and a magnitude of an image signal of each color component of an image captured by the imager. Color tone adjustment means for adjusting the color tone of the image by multiplying by a color tone adjustment coefficient which is a coefficient specified by the user, and adjusting the color tone of the image captured when the first wavelength limiting means is used. A first tone adjustment coefficient storage unit that stores the tone adjustment coefficient used for the image processing; and a tone adjustment coefficient that is used when adjusting the tone of an image captured when the second wavelength limiting unit is used. Second color tone adjustment coefficient storage means for storing The endoscope apparatus being characterized in that comprises a.

(Additional Item 8) Light source means for emitting light, image pickup means for picking up an image of an object illuminated by the light source means, and light source inserted on an optical path between the light source means and the image pickup means. A first wavelength limiter and a second wavelength limiter, which are two wavelength limiters selectively used to limit a transmission wavelength, and a setting set by a user with respect to an image taken by the imager. An image processing unit that performs image processing such as color tone emphasis in accordance with a value, and an image processing unit that performs the image processing on an image captured by the imaging unit when the first wavelength limiting unit is used. First to store setting values
Setting value storage means, and a second setting value for storing the setting value used when the image processing is performed on an image picked up by the imaging means when the second wavelength limiting means is used. An endoscope apparatus comprising: a storage unit.

(Appendix 9) Light source means for emitting light, image pickup means for picking up an image of a subject illuminated by the light source means, and a light source inserted on an optical path between the light source means and the image pickup means. A first wavelength limiting unit and a second wavelength limiting unit, which are two wavelength limiting units selectively used to limit a transmission wavelength, an image recording unit that records an image captured by the imaging unit, An image recording instructing unit for instructing recording of an image in the image recording unit, and an image captured by the imaging unit using the first wavelength limiting unit in response to one instruction from the image recording instructing unit. Control means for recording the image in the image recording means, and recording the image picked up by the image pickup means using the second wavelength limiting means in the image recording means. Mirror device.

(Appendix 10) Light source means for emitting light,
Imaging means for imaging the subject illuminated by the light source means, a dye amount calculating means for determining the amount of dye contained in the subject from the image obtained by the imaging means, and a dye amount calculated by the dye amount calculating means An endoscope apparatus comprising: display means for displaying a time change.

(Appendix 11) Light source means for emitting light,
Imaging means for imaging a subject illuminated by the light source means, laser light source means for generating treatment laser light, and wavelength of the laser light generated by the laser light source means that partially covers the light receiving surface of the imaging means Wavelength limiting means for removing the light of the first image picked up by the portion of the light receiving surface of the imaging means covered by the wavelength limiting means and the light receiving surface of the imaging means not covered by the wavelength limiting means Display means for displaying both the second image picked up by the portion or displaying either the first image or the second image.

(Additional Item 12) The endoscope apparatus according to Additional Item 11, wherein the light source means sequentially outputs lights having different wavelengths.

(Appendix 13) Light source means for emitting light,
Imaging means for imaging a subject irradiated by the light source means, laser light source means for generating laser light for treatment, laser light irradiation instruction means for instructing the laser light to be irradiated on the subject, and laser light irradiation A light amount control unit that increases a light amount output from the light source unit during laser light irradiation according to an instruction from the instruction unit; and an imaging unit during laser light irradiation according to an instruction from the laser light irradiation instruction unit. An endoscope apparatus comprising: an exposure time control unit configured to shorten an exposure time.

(Supplementary Item 14) Light source means for irradiating light to a living body to which a drug specifically accumulating in a specific lesion by an antigen-antibody reaction is previously administered, and a subject irradiated by the light source means Imaging means for imaging, and first wavelength limiting means inserted on the optical path of the light source means and the imaging means for guiding a wavelength in a first wavelength band including an effective maximum absorption peak wavelength of the drug; The first wavelength limiting means is selectively inserted on an optical path between the light source means and the imaging means, and guides a wavelength in a second wavelength band which does not include an effective maximum absorption peak wavelength of the drug. An endoscope apparatus comprising: a second wavelength limiting unit; and a display unit that displays an image captured by the imaging unit.

(Prior Art According to Supplementary Items 5 to 14) Before starting the inspection of the electronic endoscope, the color balance is set. To set the color balance, the user presses a switch for setting the color balance while capturing a reference color object serving as a white reference. In the endoscope apparatus, the color balance is set according to the switch so that the reference color object has a predetermined color on the monitor. By setting the color balance in this manner, variations (individual differences) in the wavelength characteristics of the lamp, light guide, CCD, etc. of the light source can be corrected, and observation can always be performed with a constant color tone.

Further, the preference of the color of the endoscope image differs depending on the user, and there are various persons such as a person who prefers a reddish image and a person who prefers a bluish image. In order to provide such an image according to the user's preference, the endoscope apparatus is provided with a color tone setting switch for setting the color tone of the image. Can be adjusted to color.

At the time of endoscopic observation, a medicine for diagnosis may not be used in some cases, but observation may be performed while spraying a medicine useful for diagnosis. An ICG derivative-labeled antibody has both the properties of ICG emitting fluorescence and the properties of an antibody, and binds to a specific antigen by an antigen-antibody reaction. Since the antigen-antibody reaction is extremely sensitive and extremely excellent in specificity, an ICG derivative-labeled antibody has been attracting attention as a marker indicating a specific lesion such as cancer. The presence or absence of a lesion corresponding to the antibody can be known by spraying the ICG derivative-labeled antibody into the body cavity and examining the presence or absence of fluorescence.

Further, an image processing circuit for more effectively diagnosing an image obtained by an electronic endoscope has been put to practical use, and is effective in detecting a minute lesion. In the image processing circuit, IHb color enhancement processing that enhances the color according to the amount of hemoglobin that affects the subtle color tone of the mucous membrane, adaptive structure enhancement processing that enhances the mucosal structure, or contrast enhancement processing that increases the contrast of the image The user can set values such as which processing is to be enabled and the level (strength) of the emphasizing processing by the user's preference and the target area. It can be set by switching.

Further, a digital filing device, a photographing device, a video printer, or the like is connected as an image recording device to the endoscope device, and when the user presses a release switch of the scope, the endoscope device is connected to various image recording devices. The image is recorded.

As treatment using an endoscope apparatus, laser treatment using near-infrared light is becoming widespread due to the emergence of a small high-power semiconductor laser. By irradiating laser light having a wavelength of about 810 nm emitted from a semiconductor laser through a light guide inserted into a channel of a scope, incision and coagulation of a portion to be irradiated can be performed.

(Problem of the Related Art According to Supplementary Item 4) When observing an infrared image with an infrared endoscope, fine blood vessels on the mucous membrane surface that can be seen during normal observation (observation with visible light) become invisible. There was also a problem. (Problems of the related arts according to Supplementary Items 5 and 6) Further, in the conventional infrared endoscope, the color balance corrected for the visible image is applied to the infrared image. The color of the image fluctuated depending on the individual such as the light source and the scope.

(Problem of the Related Art According to Supplementary Item 7) Since the color tone adjustment set for the visible image is applied to the infrared image in the conventional infrared endoscope, it is set in the visible image. When the desired color tone and the content of the desired color tone for the infrared image are different, the user has to switch the color tone setting every time the infrared image and the visible image are switched.

(Problem of the Related Art According to Supplementary Item 8) In the conventional infrared endoscope, since the image processing set for the visible image is also applied to the infrared image, it is performed on the visible image. If the content of the desired image processing is different from the content of the image processing desired to be performed on the infrared image, the user has to switch the image enhancement setting every time the infrared image and the visible image are switched.

(Problems of the Related Art According to Supplementary Item 9) If it is attempted to record both a visible image and an infrared image on a digital filing apparatus or the like during the conventional infrared observation,
It is necessary to perform a complicated operation such as releasing the release while displaying the infrared image, switching the filter once, displaying the visible image, releasing the release again, and switching the filter and returning to the infrared image display. Was.

(Problems of the Related Art According to Supplementary Item 10) Conventionally, the change in the concentration of ICG administered to the body is subjectively determined by looking at the contrast and color of the infrared image, and is quantitatively known. There was no means.

(Problems of Related Art According to Supplementary Items 11 to 13) In a normal endoscope, an infrared light cut filter is arranged in front of an image pickup device. In order to receive light efficiently, the infrared cut filter is removed. For this reason, when an infrared laser for treatment is used, halation occurs over a wide area of the image due to the powerful laser light, hindering observation, and hindering the operability of laser treatment.

(Problems of the Related Art According to Supplementary Item 14) In addition, a fluorescent endoscope apparatus has conventionally been required for performing a diagnosis using an ICG derivative-labeled antibody. However, IC
Since the fluorescence emitted from the G derivative-labeled antibody is very weak, a very sensitive and expensive imaging device such as an image intensifier has been required for the fluorescent endoscope.

(Problem to be Solved in Additional Item 4) Fine blood vessels on the mucosal surface are also displayed with good contrast.

(Problems to be Solved by Additional Items 5 and 6) An endoscope apparatus capable of observing both a visible image and an infrared image with a stable color balance is provided.

(Problem to be Solved by Supplementary Item 7) An endoscope apparatus capable of easily setting a desired color tone for both a visible image and an infrared image is provided.

(Problem to be Solved by Additional Item 8) An endoscope apparatus capable of easily setting appropriate image processing for both a visible image and an infrared image is provided.

(Problem to be Solved by Supplementary Item 9) An endoscope apparatus capable of easily recording both an infrared image and a visible image in a recording device is provided.

(Problem to be Solved in Supplementary Item 10) I
Provided is an endoscope apparatus capable of quantitatively knowing a temporal change in the amount of a dye such as CG.

(Problems to be Solved by Supplementary Items 11 to 13) [0214] An endoscope apparatus capable of safely performing treatment with an infrared laser even when using an infrared endoscope is provided.

(Problem to be Solved by Supplementary Item 14) An endoscope apparatus capable of observing an ICG derivative-labeled antibody without using an expensive high-sensitivity imaging device is provided.

(Function and Effect of Supplementary Item 2) Since the display means for displaying the image in the wavelength band including 930 nm as the red component or the blue component of the display means is provided, the parts where the ICG density is high and the parts where the ICG density is low are clearly colored. Can be distinguished.

(Function and Effect of Supplementary Item 3) Since the display means for displaying the image in the wavelength band including 805 nm on both the green component and the red component of the display means is provided, the sense of contrast of the displayed image is greatly increased. .

(Functions and Effects of Supplementary Item 4) Not only a wavelength band including 805 nm as a green component of the display means but also 400 to
Since an image in a wavelength band including at least a part of 590 nm is also assigned, not only blood vessels under the mucosa but also fine blood vessels on the mucosal surface are displayed with good contrast.

(Function and Effect of Supplementary Item 5) For an image picked up using the first wavelength limiting means, the color balance is corrected using the first color balance correction amount, and the second wavelength limiting means is used. The color balance is corrected using the second color balance correction amount for an image captured by using either of the above methods, so that the color balance can be appropriately corrected using either wavelength limiting means. Will be

(Function and Effect of Supplementary Item 6) Two color balance correction amounts for the first wavelength limiting unit and the second wavelength limiting unit are obtained in accordance with an instruction from the color balance setting instructing unit. Therefore, the color balance can be easily set.

(Function and Effect of Supplementary Item 7) For an image picked up using the first wavelength limiting means, the color tone is adjusted using the first color tone adjusting value, and the second wavelength limiting means is used. Since the color tone is adjusted using the second color tone adjustment value for the image picked up in this way, the color tone is appropriately adjusted when either wavelength limiting means is used.

(Function and Effect of Supplementary Item 8) The image captured using the first wavelength limiting means is subjected to image processing using the first image processing setting value, and the second wavelength limiting means is processed. Since the image processing is performed on the image captured using the second image processing setting value, the image processing is appropriately performed when either wavelength limiting unit is used.

(Function and Effect of Supplementary Item 9) In response to an instruction from the image recording instructing means, an image captured using the first wavelength limiting means and an image captured using the second wavelength limiting means are displayed. Since both are recorded, an image when both wavelength limiting means are used can be recorded by a simple operation.

(Function and Effect of Supplementary Item 10) Since the dye amount calculating means for obtaining the dye amount of the subject is provided and the calculated time change of the dye amount is displayed, the change in the dye amount can be notified quantitatively. .

(Functions and Effects of Supplementary Items 11 and 12) Since the wavelength limiting means for partially covering the light receiving surface of the imaging means and removing the laser light is provided, the halation is not affected by the treatment laser light. An image with few images is created.

(Function and Effect of Supplementary Item 13) The amount of light from the light source is increased in accordance with the instruction to irradiate the treatment laser light to the subject, and the exposure time of the imaging means is shortened. Become smaller.

(Function and Effect of Supplementary Item 14) Since wavelength limiting means for guiding wavelengths including and not including the substantial absorption peak of the drug are provided, the degree of drug accumulation can be easily known from the obtained images. be able to.

[0228]

According to the present invention, light source means for emitting light in a first wavelength band including a wavelength of 805 nm and light in a second wavelength band not including a wavelength of 805 nm, and light emitted from the light source means is provided. An imaging unit that captures an image of a first wavelength band and an image of a second wavelength band of a subject; and displaying the image of the first wavelength band captured by the imaging unit as a green component. Display means for displaying an image in the wavelength band as at least one color component of a red component or a blue component.
The image in the wavelength band including the wavelength of 05 nm is assigned to the green component which has a large effect on the human sense of contrast.
This makes it possible to observe an infrared image at the time of CG administration with good contrast.

[Brief description of the drawings]

FIG. 1 to FIG. 20 are related to a first embodiment of the present invention, and FIG. 1 is a block diagram illustrating an entire configuration of an endoscope apparatus.

FIG. 2 is an explanatory diagram illustrating a configuration of an infrared-visible switching filter.

FIG. 3 is an explanatory diagram illustrating light transmission characteristics of a visible light transmission filter and an infrared light transmission filter.

FIG. 4 is an explanatory diagram illustrating a configuration of an RGB rotation filter.

FIG. 5 is an explanatory diagram illustrating light transmission characteristics of an R filter, a G filter, and a B filter.

FIG. 6 is an explanatory diagram illustrating a configuration of a CCD.

FIG. 7 is an explanatory diagram illustrating an arrangement of an infrared light cut filter.

FIG. 8 is an explanatory diagram illustrating light transmission characteristics of an infrared light cut filter.

FIG. 9 is a block diagram illustrating a configuration of a color balance correction circuit.

FIG. 10 is a block diagram illustrating a configuration of an image processing circuit.

FIG. 11 is a block diagram illustrating a configuration of a color tone adjustment circuit.

FIG. 12 is a diagram showing an example of a screen display.

FIG. 13 is an explanatory diagram illustrating an internal memory map of a CPU.

FIG. 14 is a flowchart illustrating the flow of a filter switching process.

FIG. 15 is a flowchart illustrating a flow of color balance setting.

FIG. 16 is a flowchart illustrating the flow of color tone setting.

FIG. 17 is a flowchart illustrating a flow of an operation of laser irradiation.

FIG. 18 is a flowchart illustrating a flow of an image recording operation.

FIG. 19 is an explanatory diagram illustrating transmission characteristics of ICG.

FIG. 20 is an explanatory diagram illustrating visual spatial frequency characteristics.

21 and 22 relate to a second embodiment of the present invention, and FIG. 21 shows an R filter, a G filter, and a B filter.
Explanatory drawing explaining the light transmission characteristics of the filter

FIG. 22 is an explanatory diagram illustrating the relationship between the states of the visible-infrared switching filter and the RGB rotation filter and the operating synchronization memory;

23 to 26 relate to a third embodiment of the present invention, and FIG. 23 shows light transmission characteristics of a visible light transmission filter and an infrared light transmission filter.

FIG. 24 shows light transmission characteristics of an R filter, a G filter, and a B filter.

FIG. 25 is a block diagram illustrating a configuration of an extension multiplexer.

FIG. 26 is an explanatory diagram illustrating the light absorption characteristics of hemoglobin.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Light source device 2 ... Scope 3 ... Processor 4 ... Monitor 5 ... Digital filing device 6 ... Photographing device 7 ... Laser light source device 8 ... Lamp 9 ... Infrared-visible switching filter 10 ... Motor 11 ... RGB rotation filter 12 ... Motor 13 ... Illumination light aperture 14 ... Light guide fiber 15 ... CCD 16 ... Filter switch 17 ... Release switch 18 ... Laser irradiation switch 19 ... Scope discriminating element 20 ... Pre-processing circuit 21 ... A / D conversion circuit 22 ... Color balance correction circuit 23 ... Multiplexer 24 ... Simultaneous memory 25 ... Image processing circuit 26 ... Color tone adjustment circuit 27 ... D / A conversion circuit 28 ... Encoding circuit 29 ... Dimming circuit 30 ... Exposure time control circuit 31 ... CPU 32 ... Color balance setting switch 33 … Image processing setting switch 34… Color Setting switch 35 Visible light transmission filter 36 Infrared light transmission filter 37 R filter 38 G filter 39 B filter 40 Light receiving area 41 Horizontal transfer register 42 Infrared light cut filter 43 Correction coefficient storage memory 44 ... Selector 45 ... Multiplier 46 ... Dye amount calculation circuit 47 ... Enhancement coefficient calculation circuit 48 ... Delay circuit 49 ... Dye enhancement circuit 50 ... Structure enhancement circuit 51 ... Graph creation circuit 52 ... Image synthesis circuit 53 ... Color tone adjustment coefficient storage memory 54 ... Multiplier 55 ... Gamma correction circuit 56 ... Expansion multiplexer 57 ... Average value calculation circuit 58 ... Selector 59 ... Selector

Continued on the front page F term (reference) 2H040 BA00 BA11 CA02 CA04 CA06 CA10 CA11 CA22 DA03 DA12 GA02 GA05 GA06 GA07 GA11 4C061 AA00 BB01 CC06 DD00 LL02 MM03 NN01 NN05 QQ02 QQ03 QQ09 RR04 RR14 RR18 RR22 SS02 SS02 SS23 SS02 SS02 SS02 SS02 SS02 SS02 SS02 SS02 SS02 SS02 SS02 SS02 SS02 SS02 SS02 SS02 SS02 SS02 5C054 AA01 CA06 CB02 CC07 EA01 EB05 EB07 ED13 EE08 FA02 FE12 GA04 GB01 HA12

Claims (1)

[Claims] 1. A light source means for emitting light in a first wavelength band including a wavelength of 805 nm and light in a second wavelength band not including a wavelength of 805 nm, and illuminated by light emitted from the light source means. An imaging unit that captures an image of a subject in a first wavelength band and an image of a second wavelength band; displaying the image of the first wavelength band captured by the imaging unit as a green component; Display means for displaying an image in a wavelength band as at least one color component of a red component or a blue component.