JPH01280442A - Endoscope device - Google Patents

Abstract

PURPOSE:To observe an image in a visible area and an image to indicate the change of the oxygen saturation of a hemoglobin by providing a switching means to switch the image in the visible area with a first wavelength separating means and the image to contain the information of the oxygen saturation of the hemoglobin with a second wavelength separating means and a third wavelength separating means. CONSTITUTION:When a mirror driver 67 causes a mirror 66 to retreat from the illuminating light path of a lamp 21, the image of an observed part illuminated by the illuminating light of the lamp 21 is obtained as a visible color image in the same way as a general electronic endoscope. On the other hand, at the time of observing the change of the oxygen saturation of the hemoglobin of an organization, the mirror 66 is inserted into the illuminating light path of the lamp 21 by the mirror driver 67, the lamp 21 is extinguished by a power source 22 for a lamp, and simultaneously, a light to make 650nm into a center and a light to make 805nm into a center are light-emitted by a laser oscillator 68. The light from the laser oscillator 68 is reflected at mirrors 69 and 66, it is made incident on a light guide 14, and the observed part by an electronic endoscope 70 is illuminated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an endo-im device that enables observation of changes in oxygen saturation of hemoglobin in blood.

[Prior Art] In recent years, it has become possible to observe organs within a body cavity by inserting an elongated insertion section into a body cavity, and to perform various therapeutic procedures as necessary using a treatment instrument inserted into a treatment instrument channel. Endoscopes are widely used.

In addition, solid-state imaging devices such as charge-coupled devices (CODs) are
Various electronic endoscopes used as imaging means have also been proposed.

Also, in recent years, the electronic? J! What about traditional fiberscopes due to ffl? 6JAn endoscopic device has been proposed for observing lesions and changes in mucous membranes that have been difficult to detect.

By the way, it is known that knowing the distribution of oxygen saturation of hemoglobin in blood (the proportion of hemoglobin bound to oxygen among hemoglobin in blood) is useful for early detection of lesions. The oxygen saturation of hemoglobin in blood can be measured by measuring wavelengths at which the absorbance does not change due to changes in oxygen saturation, such as 569 nm and 586 nm, and wavelengths at which absorbance changes significantly due to changes in oxygen saturation, such as at 577 nm. There is a method of measuring changes in oxygen saturation in mucous membranes based on the difference in absorbance.

Further, for example, in the fundus camera disclosed in Japanese Utility Model Application Publication No. 61-151704, an oxygen saturation image is obtained from the difference between two wavelengths.

[Problems to be Solved by the Invention] However, although it is possible to measure each region using a conventional oxygen saturation measurement device, it is difficult to obtain an image of oxygen saturation.

Furthermore, when trying to obtain an oxygen saturation image using a wavelength where the absorbance does not change due to a change in oxygen saturation and a wavelength where the absorbance greatly changes due to a change in oxygen saturation, as in the camera shown in the conventional example, Since the wavelength at which absorbance does not change due to changes in oxygen saturation is a single wavelength, a sufficient amount of light cannot be obtained and imaging is difficult.

Furthermore, if the wavelength range is fixed as in the conventional camera, images in the general visible range cannot be obtained, and lesions cannot be detected from the subtle color tones of mucous membranes.

[Objective of the Invention] The present invention has been made in view of the above circumstances, and has made it possible to observe images in the general visible region and images showing changes in the 11i element saturation of hemoglobin in mucous membranes, etc. The purpose is to provide an endoscope device.

[Means for Solving the Problems] An endoscope apparatus of the present invention includes an endoscope having at least an imaging optical system, an imaging means for imaging a subject image formed by the imaging optical system, and a visible a first wavelength separation means for separating a subject image into images of a plurality of wavelength regions in order to obtain an image of a region; and a first wavelength separation means for separating a subject image into images of a plurality of wavelength regions; a second wavelength separation means for separating images in a wavelength band that does not change; and a second wavelength separation means for separating images in a wavelength band in which the amount of light incident on the light receiving section of the imaging means changes due to a change in oxygen saturation of hemoglobin. wavelength separation means 3; and a switching means for switching between an image in the visible region obtained by the first wavelength separation means and an image containing information on the oxygen saturation of hemoglobin obtained by the second wavelength separation means and the third wavelength separation means. It is equipped with the following.

[Function] In the present invention, an image in the visible region is obtained by the first wavelength separation means, an image including information on the oxygen saturation of hemoglobin is obtained by the second wavelength separation means and the third wavelength separation means, These two types of images are switched by a switching means. In addition, the second wavelength separation means and the third wavelength separation means each detect not only a single wavelength but also a pre-negative l incident on the light receiving section of the flit imaging means due to a change in the oxygen saturation of the hemoglobin. A sufficient amount of light can be obtained because a wavelength band that does not change and a wavelength band in which the amount of light incident on the light receiving section of the image carrier changes depending on changes in the oxygen saturation of hemoglobin are set.

[Example] Hereinafter, the present invention will be described in detail with reference to the drawings.

FIGS. 1 to 8 relate to the first embodiment of the present invention.
Figure 2 is a block diagram showing the configuration of the endoscope device, Figure 2 is an explanatory diagram showing a rotating filter, Figure 3 is an explanatory diagram showing the transmission wavelength range of each filter in the rotating filter, and Figure 4 is an explanatory diagram showing each band-limiting filter. Fig. 11 shows the transmission wavelength range of , Fig. 5 is a side view showing the whole of the Naiho 11 device, Fig. 6 is an explanatory diagram showing the absorption spectra of oxyhemoglobin and deoxyhemoglobin, and Fig. 7 shows changes in oxygen concentration. FIG. 8 is an explanatory diagram showing a change in the absorbance of hemoglobin due to a change in the absorbance of hemoglobin. FIG.

The endoscope apparatus of this embodiment includes an electronic endoscope 1, as shown in FIG. The electronic endoscope 1 has an elongated, for example, flexible insertion section 2, and a large-diameter operation section 3 is connected to the rear end of the insertion section 2.

A flexible universal cord 4 extends laterally from the rear end of the operating section 3, and a connector 5 is provided at the tip of the universal cord 4.

The electronic endoscope lt1 is connected via the connector 5 to a video processor 6 having a built-in light source device and a signal processing circuit.
It is designed to be connected to. Furthermore, a monitor 7 is connected to the video processor 6.

On the distal end side of the insertion portion 2, a rigid distal end portion 9 and a bendable portion 10 adjacent to the distal end portion 9 and capable of bending toward the rear side are sequentially provided. Furthermore, by rotating a bending operation knob 11 provided on the operating section 3, the bending section 10 can be bent in the left-right direction or the up-down direction. Further, the operation section 3 is provided with an insertion port 12 that communicates with a treatment instrument channel provided in the insertion section 2.

As shown in FIG. 1, inside the insertion section 2 of the electronic endoscope 1,
A light guide 14 that transmits illumination light is inserted.

The distal end surface of this light guide 14 is located at the distal end 9 of the insertion section 2.
The distal end portion 9 can emit illumination light. Further, the incident end side of the light guide 14 is inserted into the universal cord 4 and connected to the connector 5. Further, the tip portion 9 is provided with an objective lens system 15, and a solid-state image sensor 16 such as a COD is disposed at the imaging position of the objective lens system 15. This solid-state image carrier 16 has sensitivity in a wide wavelength range from the visible region to the infrared region. Signal lines 26.27 are connected to the solid-state image sensor 16, and these signal lines 26.2
7 is inserted into the insertion portion 2 and the universal cord 4 and connected to the connector 5.

On the other hand, inside the video processor 6, a lamp 2 such as a xenon lamp that emits a broadband light ranging from visible light to infrared light is installed.
1 is provided. This lamp 21 is configured to be supplied with electric power by a lamp power source 22. A rotary filter 50 that is rotationally driven by a motor 23 is disposed in front of the lamp 21 . As shown in FIG. 2, this rotating filter 50 includes filters 50R and 50G that transmit light in the red (R), green (G), and blue (B) wavelength regions for normal visible region observation; 50B and specific wavelength ranges IR1, IR2, IR3 in the infrared region to color image changes in oxygen saturation of hemoglobin.
Filters 50a, 50b, and 50c that transmit the light of
50R, 50a.

50G, 50b, 50B, 50c in order, that is, R
, IRy, G, IR2, B, and IR3 are arranged along the circumferential direction in this order. The transmission characteristics of each filter of this rotary filter 50 are shown in FIG.

Further, the motor 23 is driven with its rotation controlled by a motor driver 25.

Moreover, between the rotary filter 50 and the lamp 21,
Two band-limiting filters 51 and 52 are provided which are driven by a filter drive device 53 to be inserted into and removed from the illumination optical path. As shown in FIG. 4, one of the band-limiting filters 51 is configured to transmit a visible region of approximately 650 nm or less, and the other band-limiting filter 52 is configured to transmit an infrared region of approximately 650 nm or more.

Further, a switching circuit 55 is provided for switching between a normal visible image and an image showing changes in oxygen saturation of hemoglobin.
The filter driving device 53 inserts one of the band-limiting filters 51 and 52 into the illumination optical path in accordance with the designation of the switching circuit 55. That is, when a normal visible image is selected, the band-limiting filter 51
However, when an image showing a change in oxygen saturation of hemoglobin is selected, a band-limiting filter 52 is inserted into the illumination optical path. When the band-limiting filter 51 is inserted into the illumination optical path, the illumination light is separated in time series into light in the R, G, and B wavelength regions by the rotating filter 50.
When the band-limiting filter 52 is inserted into the illumination optical path, the illumination light is divided into IRl and IR2 by the rotating filter 50.
, IR3 wavelength ranges are separated in time series.

R, G, B or IRl, In2. I
The light separated in time series into light in each of the n2 wavelength regions is incident on the input end of the light guide 14, guided to the tip 9 via the light guide 14, and emitted from the tip 9. to illuminate the observation area.

The returned light from the observation site due to the illumination light is imaged by the objective lens system 15 onto the solid-state image sensor 16 and photoelectrically converted. This solid-state image sensor 16 is connected to the video processor 6 via the signal line 26.
A drive pulse is applied from a driver circuit 31 within the memory, and reading and transfer are performed by this drive pulse. The video signal read out from the solid-state image sensor 16 is input to a preamplifier 32 provided within the video processor 6 or within the electronic endoscope 1 via the signal line 27.

The video signal amplified by the preamplifier 32 is input to a process circuit 33, subjected to signal processing such as γ correction and white balance, and converted into a digital signal by an A/D converter 34. This A/D
The video signal which is A/D converted in time series by the converter 34 is distributed by the switch circuit 35,
Three memories (1) in which video signals of each wavelength correspond to each color, for example, red (R), green (G), and blue (B).
36a, memory (2) 36b, and memory (3) 36c.

The memory (1) 36a and the memory (2) 36b.

Memories (3) 36C are read out at the same time, respectively.
The signals are converted into analog signals by the D/A converters 37, 37, and 37, and are input to the matrix circuit 38. When the illumination light is R, G, or B, the matrix circuit 38 generates a luminance signal Y and a color difference signal RY from the RlG and B signals output from each D/A converter 37.

B-Y, while the illumination light is IRI, In2゜In
In case 2, the pseudo-colored luminance signal Y and the color difference signals R-Y, B-Y are generated from the pseudo-colored R, G, and B signals output from each D/A converter 37. I am supposed to make it. The luminance signal @Y and color difference signals R-Y, B-Y from the matrix circuit 38 are sent to an encoder 39.
The encoder 39 converts the luminance signal Y and the color difference signals RY and B-Y into NTSC video signals and outputs them. Then, this NTSC video signal is input to the monitor 7, and the monitor 7
The observed area is displayed in color.

Further, R output from each D/A converter 37,
The G and B signals are also input to a selector circuit 45. This selector circuit 45 selects each D/A converter 37 in response to a selection signal from a selection means (not shown).
Two types of video signals are selected from three types of video signals outputted from the system. The two types of video signals output from this selector circuit 45 are sent to an arithmetic circuit 46.
It is now entered into This arithmetic circuit 46 is
The difference between the two types of video signals is exclusively output. The output signal of the arithmetic circuit 46 is input to a monitor, and a monochrome image showing changes in the oxygen saturation of hemoglobin is displayed on the monitor.

Further, within the video processor 6, there is provided a timing generator 42 that generates the timing of the entire system, and the driver circuit 31 and each other circuit are synchronized by this timing generator 42.

Further, the switching circuit 55 is connected to R of the rotary filter 50,
G, B or IRI, In2. In2, which timing of the solid-state image sensor 16 is to be read is specified, and the switch circuit 35 is switched in synchronization with the read timing of the solid-state image sensor 16.

Next, the operation of this embodiment will be explained with reference to FIGS. 6 to 8.

First, when observing an image in a normal visible region, a band-limiting filter 51 is inserted into the illumination optical path.

Then, the lamp 21 is turned on using the lamp power supply 22, and
Light ranging from the visible light region to the infrared light region is emitted, and is made to enter the rotary filter 50 as light only in the visible light region by the band-limiting filter 51 .

This rotary filter 50 performs color separation into R, G, and 8 wavelength regions in time series, allows light to enter the light guide 14, and also filters IRt, IF5, and In2.
The sections 0a, 50b, and 50c are light-blocking periods, and the solid-state image sensor 16 can read out R, G, and B images during the light-blocking periods.

The light incident on the light guide 14 is transmitted to the observation site by the endoscope 1 inserted into the body cavity, and illuminates the observed tissue in chronological order. The reflected light from the illuminated area is converted into an optical image by the objective lens system 15, and this optical image is photoelectrically converted by the solid-state imager 16. The output signal of this solid-state R image tree 16 is transmitted to the preamplifier 32. The process circuit 33 processes the signal, and the A/D converter 34
The signal is converted into a digital signal by the switch circuit 35, and the R image is recorded in the memory <1) 36a, the G image is recorded in the memory (2) 36b, and the B image is recorded in the memory (3) 36c. These memories 36a, 36b.

The video signal read from 36C is converted into an analog signal by the D/A converter 37, and then converted to an analog signal by the matrix circuit 38.
The signals are converted into a rating signal and a color difference signal at the encoder 39, and converted into an NTSCIn signal at the encoder 39, which is output to the monitor 7. Then, on this monitor 7, a color image in a normal visible range is displayed.

On the other hand, when observing an image showing changes in oxygen saturation of hemoglobin, the band-limiting filter 52 is inserted into the illumination optical path. The light in the infrared region that has passed through the band-limiting filter 52 is passed through the rotating filter 50 in a time-series manner by IRt.
, IF5. The light is separated into different wavelength regions of In2 and enters the light guide 14. In addition, R, G, and B filters 50
The sections R, 50G, and 50B are light shielding periods.

IRt, IF5. The reflected light from the observation site illuminated in time series with In2 light is converted into an optical image by the objective lens 15 and photoelectrically converted by the solid-state image sensor 16, as in the case of R, G, and B illumination. .

The output signal of this solid-state 1D image element 16 is transmitted to a preamplifier 32.
, process circuit 33. Through the A/D converter 34° switch circuit 35, the image of IRl is stored in the memory (<1) 36a, the image of IF5 is stored in the memory (2) 36b, and the image of IF5 is stored in the memory (2) 36b.
) 36c, the images of In2 are recorded respectively. These memories 36a, 36b.

The 'video signal read out from 36C is converted into an analog signal by the D/A converter 37, and the
7 outputs video signals of images in each wavelength region of IR1, IF5, and In2.

Here, as shown in FIGS. 6 and 7, the spectral characteristics of the absorbance of hemoglobin in blood changes depending on its oxygen saturation. In this example, the wavelength range IR1 is within the wavelength range of 600 to 700 nm, where the absorbance changes greatly depending on the oxygen saturation, and the rate of change is small compared to the narrow band IR2 and IR1 centered around 805 nm, where there is almost no change in absorbance. The images in each wavelength region IR3 of about 900 to 11000 nm, in which differences due to changes in oxygen saturation can be detected, are each converted into pseudocolor. The video signals from each D/A converter 37 are processed by a matrix circuit 38 as a pseudo color difference signal, converted into an NTSC video signal by an encoder 39, and outputted to the monitor 7. The difference in tissue oxygen saturation is displayed on the monitor 7 in pseudo color.

By the way, the wavelength at which the absorbance does not change due to changes in oxygen saturation is a single wavelength of approximately 800 nm, but if the light from the light source is limited by a very narrow band filter in order to obtain an image of this single wavelength, the amount of light will decrease. Due to the shortage, it becomes difficult to visualize. Furthermore, errors due to slight shifts in the transmission wavelength of the filter become large.

Therefore, in this embodiment, as shown in FIG. 8, as a wavelength band (IF5) in which the amount of light incident on the solid-state image sensor 16 does not change due to a change in the oxygen saturation of hemoglobin, a short wavelength of the isoabsorbance point (805 nm) is used. A wavelength band λ1 or λ2 is set that has a certain width including the long wavelength side and the long wavelength side. In this wavelength band λ1゜λ2, the absorbance changes depending on the oxygen saturation on the short wavelength side and long wavelength side of the isoabsorbance point, so even if there is a certain width, the oxygen saturation will change. The light R incident on the solid-state image sensor 16 hardly changes due to a change in the degree of illumination. In this way, by setting 16 wavelength bands with a certain width, it is possible to obtain a sufficient amount of light for imaging, and to obtain an image that does not affect the video signal level in practical use due to changes in oxygen saturation. I can do it.

Further, the selector circuit 45r includes each D/A converter 37.
Two types of video signals are selected from among the video signals in each wavelength range from . For example, when the IRt and IRz video signals are selected, the brightness rendering circuit 46 detects the difference between the respective video signals, and displays the image of this difference in monochrome on the monitor. Therefore, with this image, changes in oxygen saturation in the tissue can be observed with good contrast.

As described above, according to this embodiment, color images in the general visible range enable conventional medical examination based on changes in color tone in tissues, and changes in the oxygen saturation of hemoglobin in tissues can be detected using pseudocolor images. By converting the images into monochrome or monochrome, they can be viewed as images with good contrast. Therefore, early detection of lesions is possible, and diagnostic performance is improved by comparison with conventional color images.

Note that changes in oxygen saturation may be observed by selecting and displaying only IRz using the selector circuit 45.

9 to 13 relate to a second embodiment of the present invention, in which FIG. 9 is a block diagram showing the configuration of the endoscope 11 device, FIG. 10 is an explanatory diagram showing a rotating filter, and FIG. 11 is a hemoglobin An explanatory diagram showing changes in absorbance due to changes in oxygen saturation of
Fig. 12 is an explanatory diagram showing the transmission wavelength region of each filter for image formation showing changes in hemoglobin oxygen saturation in the rotating filter, and Fig. 13 is an explanatory diagram showing the transmission wavelength range of each filter for image formation, showing the change in hemoglobin oxygen saturation in the rotating filter. FIG. 2 is an explanatory diagram showing wavelength regions.

In this embodiment, the band-limiting filter 5 in the first embodiment is
1, 52, filter drive device 53 is not provided.

Further, instead of the rotary filter 50, a rotary filter 60 as shown in FIG. 10 is provided. This rotating filter 60 includes filters 60R, 60G, and 60B that transmit light in the R, G, and B wavelength regions for normal visible region observation.
and a specific wavelength range in the visible region [Gt.

Filters 60a and 60b that transmit the light of G2 and G3,
5Qc is 60R, 60a, 60G, 60b, 60B
, 60c, that is, R, G1°G, G2, B
, G3 along the circumferential direction. Said G1
．． The wavelength regions of G2 and G3 are shown in FIG. As shown in FIGS. 11 and 12, the G1. The G2 and G3 wavelength regions are regions in which the absorbance changes depending on changes in the oxygen saturation of hemoglobin, and G+,
Between G2 and G2.03, the absorbance changes depending on the oxygen saturation. Further, in this embodiment, the lamp power source 22 is controlled by the switching circuit 55, and the lamp 21 is connected to the G1. G2,
Light is emitted at the timing of G3 or the timing of R2O,B.

The other configurations are the same as in the first embodiment.

In this example, for lamps! +1!22 and the lamp 21 to R and G at the timing from the switching circuit 55.

B or G], G2, and G3, the light guide 14 is provided with R, G, B, or G1. Color-separated light enters G2 and G3.

When R, G, and B lights are incident, signal processing is performed in the same manner as in the first embodiment, and a color image in a general visible range is obtained. On the other hand, G1. When observing using light separated into G2 and G3, as in the first embodiment, G1. G2
, G3 are each pseudo-colored, and changes in oxygen saturation (also referred to as S02) are observed.

Also, G1. Since each video signal of G2 and G3 changes due to the difference in Mi saturation, by detecting the difference between the two types of video selected by the selector circuit 45, changes in oxygen saturation are detected as changes in brightness in monochrome images. It is visualized as.

According to this embodiment, G1. Absorbance changes in all wavelength regions of G2 and G3 due to changes in acid saturation, and
Between G+ and 02, and between G2 and G3, the absorbance changes depending on the oxygen saturation, so compared to the first example, it is easier to observe changes in oxygen saturation using color images. becomes easier.

Also, G1. Since the G2 and G3 wavelength regions have a lower tissue transmission number than the infrared light region, it is possible to detect the MX saturation level only on the tissue surface.

In addition, as the wavelength region of Gl and G3, λ shown in FIG.
4. Like λ3, the absorbance changes depending on the oxygen saturation on the short wavelength side and long wavelength side of the isosbestic point, so there is almost no change in the video signal level due to changes in oxygen saturation. may be set. In this way, by setting a wavelength band having a certain width including the short wavelength side and the long wavelength side of the isoabsorbance point, it is possible to obtain a sufficient light indication for imaging.

Other functions and effects are similar to those of the first embodiment.

14 to 17 relate to the third embodiment of the present invention,
Fig. 14 is a block diagram showing the configuration of the endoscope device;
FIG. 16 is an explanatory diagram showing a mosaic filter, FIG. 16 is an explanatory diagram showing the transmission wavelength range of each filter of the mosaic filter, and FIG. 17 is an explanatory diagram showing the emission characteristics of a laser oscillation device.

This embodiment is an example in which a simultaneous method is used as the color 111@ method.

As shown in FIG. 14, the electronic endoscope 7 in this embodiment
A solid-state imaging element 71 is disposed at the imaging position of the objective lens system 15 provided at the distal end 9 of the insertion section 0, and a mosaic filter 72 is provided in front of the solid-state imaging element 71. There is. As shown in FIG. 15, the mosaic filter 72 is configured by arranging filters in a mosaic pattern that transmit light in each wavelength region of green (G), cyan (Cy), and yellow (Ye). The transmission wavelength range of each filter of this mosaic filter 72 is shown in FIG. As shown in this figure, in this embodiment, each filter also transmits infrared light. Other configurations of the electronic endoscope 70 are as follows:
This is the same as the electronic endoscope 1 of the first embodiment.

On the other hand, on the video processor side, as a light source, there is a lamp 21 that is supplied with power from a lamp power source 22 and emits light in a wide band from visible light to infrared light, and a laser oscillation device that has light emission characteristics as shown in FIG. A device 68 is provided. A mirror 6 whose surface facing the light guide 14 is a reflective surface is provided between the lamp 21 and the incident end of the light guide 14.
6 is removably provided in the illumination optical path. This mirror 66 is inserted into and removed from the illumination optical path by a mirror drive device 67, and when inserted into the illumination optical path, the reflective surface is at approximately 45 degrees with respect to the optical axis. Further, in front of the laser oscillation device 68, there is a device for guiding the light emitted from the laser oscillation device 68 to a mirror 66 inserted in the illumination optical path, and making it enter the light guide 14 via this mirror 66. A mirror 69 is provided. In this way, when the mirror 66 is retracted from the illumination optical path, the light from the lamp 21 enters the light guide 14, and when the mirror 66 is inserted into the illumination optical path, the light from the laser oscillation device 68 enters the light guide 14. light is mirror 6
9.66 and enters the light guide 14.

Return light from the observation site due to the illumination light emitted from the light guide 14 is transmitted through the mosaic filter 72 and transferred to the solid-state imager 71 by the objective lens system 15.
An image is formed on top and photoelectrically converted. A drive pulse from a driver circuit 75 in the video processor is applied to the solid-state image carrier 71 via a signal line 74, and reading and transfer are performed by this drive pulse. The video signal read from the solid-state image device 16 is inputted via a signal line 73 to a preamplifier 78 provided within the video processor or the electronic endoscope. This preamp 7
The video signal amplified in step 8 is passed through a low-pass filter (hereinafter referred to as LPF) 81 that separates the luminance signal, and an LPF 8 that separates the narrowband luminance signal for color difference signal generation.
3 and a bandpass filter (hereinafter referred to as B()) that separates the color signal modulated by the Mojik filter 72.
.

)85. Said LPF81
The bright turtle signal is input to a process circuit 82 and subjected to signal processing such as waveform shaping and γ correction. Furthermore, the narrowband luminance signal from the LPF 83 is
Similarly, the signal is input to a process circuit 84 and subjected to signal processing. Further, the output signal of the BPF 85 is transmitted to a 1Hf relay line (hereinafter referred to as IHDL) 86. which delays the signal by a period of 11-1. The signal is input to an adder 87 and a subtracter 88. The adder 87 combines the direct signal from the BPF 85 and the 1l-IDL8
6 and the signal extended by IHilV at 1 HDL 86, and the n reducer 88 subtracts the direct signal from BPF 85 and the signal extended by 1t-In at 1HDL 86. The respective output signals of the adder 87 and the subtracter 88 are subjected to γ correction in γ correction circuits 89 and 90, and the respective modulated color signals are demodulated in demodulation circuits 91 and 92. There is. I) The narrowband power-saving signal from the hiss circuit 84 and the color signals from the demodulation circuits 91 and 92 are input to the matrix circuit 93, and the 7-trix circuit 92 generates a color difference signal. It has become. The color difference signal from the matrix circuit 93 and the brightness If from the IL7 bus circuit 82 (No. 3 is the color encoder 9
4, and this color encoder 94 outputs the NTS
It is converted into a G signal. And this N
The TSC signal is input to the monitor 7, which displays the TIA detection site in color.

Further, the process circuit 84. Each color signal from the demodulation circuits 91 and 92 is also input to a selector circuit 95. This selector circuit 95 is configured to select and output two types of video signals from the three types of video signals in response to a selection signal from a selection means (not shown). The two types of video signals output from the selector circuit 95 are input to a performance circuit 96. This arithmetic circuit 96 is configured to calculate and output the difference between the two types of video signals. The output signal of this arithmetic circuit 96 is input to the monitor, and on this second day, a monochrome image showing changes in the oxygen saturation of hemoglobin is displayed.

Further, a timing generator 76 that generates timing for the entire system is provided within the video processor, and the driver circuit 75 and each other circuit are synchronized by this timing generator 76.

Next, the operation of this embodiment will be explained.

When the mirror drive device 67 retracts the mirror 66 from the illumination light path of the lamp 21, the image of the observation region illuminated by the illumination light of the lamp 21 is visible, similar to an in-shell electronic endoscope. A color image of 10 is obtained.

On the other hand, when observing changes in the oxygen saturation of hemoglobin in tissues, the mirror 66 is inserted into the illumination optical path of the lamp 21 using the mirror driver 8 device 67, and the lamp 21 is turned off using the lamp power source 22. In addition, the laser excavation V device 68 emits light centered at 650 nm as shown in FIG.
It emits light centered at 0.05 nm. The light from the laser firing device 68 is reflected by mirrors 69, 66, and
The light enters the light guide 14 and illuminates the area observed by the electronic endoscope 70. Here, laser light has a single wavelength and is extremely powerful, with high energy density per unit wavelength.
It is possible to sufficiently visualize the image using illumination using this laser light. The laser light emitted from the light guide 14 illuminates the mucosal tissue, and the reflectance of the laser light around 65 Qnm changes greatly due to the change in the oxygen saturation of hepeptidontal globin in the tissue, and the reflectance of the laser light around 805 nm changes significantly. Its reflectance hardly changes. The light reflected from the tissue is converted into an optical image by the objective lens system 15, passes through the mosaic filter 72, and forms an image on the light receiving surface of the solid-state image carrier 71. Here, since the mosaic filter 72 has transmission characteristics as shown in FIG.
Since only the Ye filter passes through it, it is processed as an R signal, and when illuminated with 850 nm light, Cy, Ye, and G pass through all the filters, so it is pseudo-color processed as a G signal, and the signal is sent from the color encoder 94. Output. At this time, by selecting the R and G video signals in the selector circuit 95 and detecting the difference between these video signals in the arithmetic circuit 96, the difference in oxygen saturation in the mucosal tissue can be detected.
Display is possible due to the density difference.

Furthermore, during illumination by the lamp 21, it is also possible to select G and R video signals using the selector circuit 95, detect the difference between them using the N circuit 96, and visualize the difference.

As described above, according to this embodiment, the first. Similar to the second embodiment, changes in hemoglobin oxygen saturation in mucosal tissues can be visualized. Also, 1st. Since color separation is not performed in time series as in the second embodiment, there is no time lag when performing calculations between images of different wavelengths, so that there are few mathematical errors.

Furthermore, since laser light is used, it is possible to select the most effective wavelength in a narrower band.

Note that the illumination light for observing changes in the oxygen saturation of hemoglobin is not limited to laser light, and a light source such as the LED 69 may be used.

The operation and effect of the second embodiment are the same as those of the first embodiment.

It should be noted that the present invention is not limited to the above-mentioned embodiments; for example, the first embodiment
Or in the third embodiment, the endoscope 1f! The eastern part of J may be observed using transmitted illumination. In this case, the illumination may be performed from outside the living body, or the light may be guided into the living body and only the tissues may be illuminated through the light.

Furthermore, the present invention is applicable not only to electronic endoscopes having a solid-state imaging element at the distal end of the insertion part, but also to the eyepiece part of an endoscope capable of visual observation such as a conventional fiberscope, or to the eyepiece part. In place of this, an external device having a solid-state imaging device such as a COD can also be applied to an endoscope device that is used by connecting a television camera.

Furthermore, the wavelength band for observing changes in the oxygen saturation of globin is not limited to those shown in each embodiment, and can be arbitrarily selected and set.

[Effects of the Invention] As explained above, according to the present invention, an image in the visible region can be obtained by the first wavelength separation means, and the oxygen saturation of hemoglobin can be determined by the second wavelength separation means and the third wavelength separation means. Since an image including information on - can be obtained, it is possible to observe an image of the visible region within the membrane and an image showing changes in the oxygen saturation of hemoglobin in the mucous membrane and the like.

[Brief explanation of the drawing]

FIGS. 1 to 8 relate to the first embodiment of the present invention.
Figure 2 is a block diagram showing the configuration of the endoscope device, Figure 2 is an explanatory diagram showing a rotating filter, Figure 3 is an explanatory diagram showing the transmission wavelength range of each filter in the rotating filter, and Figure 4 is an explanatory diagram showing each band-limiting filter. Fig. 5 is a side view showing the entire endoscope device, Fig. 6 is an explanatory drawing showing the absorption spectrum of oxyhemoglobin and deoxyhemoglobin, and Fig. 7 is an explanatory drawing showing the transmission wavelength range of oxygen. An explanatory diagram showing changes in the absorbance of hemoglobin due to changes in concentration. Figure 8 is an explanatory diagram showing the wavelength band in which the appearance of light incident on the light receiving section does not change due to changes in oxygen saturation. Figures 9 to 13 are diagrams from this book. Regarding the second embodiment of the invention, FIG. 9 is a block diagram showing the configuration of the endoscope device, and FIG.
Figure 0 is an explanatory diagram showing a rotating filter. Figure 11 is an explanatory diagram showing changes in absorbance due to changes in hemoglobin oxygen saturation. Figure 12 is an explanatory diagram showing changes in hemoglobin oxygen saturation in a rotating filter. 1 For image formation. FIG. 13 is an explanatory diagram showing the transmission wavelength range of two filters of the rotating filter in a modification of the second embodiment, and FIGS. 14 to 17 are diagrams showing the transmission wavelength range of each filter of the present invention. Regarding the third embodiment, FIG. 14 is a block diagram showing the configuration of the endoscope device, FIG. 15 is an explanatory diagram showing the mosaic filter, and FIG.
The figure is an explanatory diagram showing the transmission wavelength range of each filter of the mosaic filter, and FIG. 17 is an explanatory diagram without showing the emission characteristics of the laser oscillation device. 1... Electronic endoscope 6... Video processor 7... Monitor 15... Objective lens system 1
6...Solid image carrier 21...Lamp 50...
Rotating filter Fig. 2 50b Fig. 3 Liquid length (nm) Fig. 4 5 Skin moxibustion (nm) Fig. 6 Fig. 8 Gold line

Claims (1)

[Scope of Claims] An endoscope having at least an imaging optical system; an imaging means for imaging a subject image formed by the imaging optical system; and an imaging means for capturing a subject image formed by the imaging optical system; a first wavelength separation means for separating into images in a plurality of wavelength ranges; and a first wavelength separation means for separating into images in a wavelength range in which the amount of light incident on the light receiving section of the imaging means hardly changes due to a change in oxygen saturation of hemoglobin. a second wavelength separation means; a third wavelength separation means for separating images in a wavelength band in which the amount of light incident on the light receiving section of the imaging means changes due to a change in oxygen saturation of hemoglobin; It is characterized by comprising a switching means for switching between an image in the visible region produced by the wavelength separation means and an image containing information on oxygen saturation of hemoglobin produced by the second wavelength separation means and the third wavelength separation means. Viewing device.