JPH01297042A - Endoscope device - Google Patents

Abstract

PURPOSE:To selectively obtain the image of a general visible area and an image with a specific wavelength area by inserting and removing a wavelength restricting means into the from an illuminating light path or observing light path in an endoscope having an image-forming optical system. CONSTITUTION:On the illuminating light path between a rotary filter 50 and a light guide 14 incident edge, a band-pass filter turret 51 is arranged, and for example, five kinds of filters 51a, 51b, 51c, 51d and 51e having band-pass characteristics to be different, respectively, are arranged along a circumference direction. A filter switching device 55 is controlled by a switching circuit 43, and when one among respective filters 51a-51e of the band-pass filter turret 51 is selectively made to intervene in the illuminating light path, the wavelength area of a light transmitted through the rotary filter 50 is restricted by the selected filter. Thus, when the wavelength restricting means is made to retreat from the illuminating light path and observing light path, the color image of the visible area can be obtained, and when the means is inserted, the image with the specific wavelength area can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an endoscope device that can obtain images in a general visible range and images in a specific wavelength range.

[Problems to be solved by conventional techniques and inventions] In recent years,
By inserting the elongated insertion section into the body cavity, internal organs, etc. can be inserted into the body cavity. BACKGROUND ART Endoscopes are widely used in dormitories and can perform treatment every second using a treatment instrument inserted into a treatment instrument channel as needed.

Furthermore, various electronic endoscopes using solid-state imaging devices such as charge-coupled devices (CODs) as imaging means have been proposed.

By the way, it is known that knowing the distribution of hemoglobin levels and oxygen saturation in blood is useful for early detection of lesions. As a method for determining hemoglobin level and oxygen saturation in blood, for example,
As shown in the above publication, there is a method of obtaining the hemoglobin from images in a plurality of specific wavelength regions related to hemoglobin in blood.

However, since the observation wavelength range is fixed in the camera shown in the conventional example, color images in the visible range cannot generally be obtained. For example, a special image containing blood information and an image in the general visible range cannot be obtained. It was not possible to compare.

[Object of the Invention] The present invention has been made in view of the above circumstances, and provides an endoscope device that can obtain images in a general visible range and images in a specific wavelength range. is intended to provide.

[Means for solving the problem] Among the present invention? The J2 mirror device includes at least an endoscope that includes an imaging optical system, a color separation means that separates a subject image into images in a plurality of wavelength regions to obtain a color image, and an image forming system that uses the imaging optical system. and an M image means for transporting images of each wavelength region separated by the color separation means, and an M image means which is removably installed on the illumination optical path or observation optical path leading to the image pickup means, and the color separation means It is equipped with wavelength limiting means that can transmit a part of the wavelength long chain region to be separated.

[Function] In the present invention, when the wavelength limiting means is retracted from the illumination optical path or the observation optical path, the subject image is color separated by the color separation means, and it becomes possible to obtain a color image in a general visible range. When the wavelength limiting means is inserted, it becomes possible to obtain an image in a specific wavelength range limited by the wavelength limiting means.

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

1 to 12 relate to a first embodiment of the present invention, in which FIG. 1 is a block diagram showing the configuration of an endoscope device, FIG. 2 is an explanatory diagram showing a bandpass filter turret, and FIG. A side view showing the entire endoscope device, Figures 4 and 5 are explanatory diagrams showing changes in blood absorbance due to changes in oxygen saturation of hemoglobin, and Figure 6 shows the transmission wavelength range of each filter of the rotating filter. Figures 7 to 11 are explanatory diagrams showing the transmission wavelength range of each filter of the bandpass filter turret, and Figure 12 is a block diagram showing a processing circuit for determining hemoglobin 11 and oxygen saturation. It is a diagram.

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 cable 4 is connected to the side from the rear end of the operating section 3.
is extended, and a connector 5 is provided at the tip of this cable 4. The electronic congratulation 111 is connected to the connector 5
It is connected to a video processor 6 in which a light source device and a signal processing circuit are built-in. 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 operating 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 carrier 16 is disposed at the imaging position of the objective lens system 15. This solid-state image sensor 16 has sensitivity in a wide wavelength range from the element body region to the infrared region, including the visible region.

Signal lines 26 and 27 are connected to the solid-state image carrier 16, and these signal lines 26 and 27 are inserted into the insertion section 2 and the universal cord 4 and connected to the connector 5.

On the other hand, inside the video processor 6, a lamp 21 is provided that emits a wide band of light ranging from ultraviolet light to infrared light. As this lamp 21, a general xenon lamp, a strobe lamp, or the like can be used. The xenon lamp and strobe lamp emit not only visible light but also ultraviolet light and infrared light to the ship. This lamp 21 is configured to be supplied with electric power by a power supply section 22. A rotary filter 50 that is rotationally driven by a motor 23 is disposed in front of the lamp 21 .

In the rotating filter 50, filters that transmit light in the red (R), green (G), and blue (B) wavelength regions for normal observation are arranged along the circumferential direction.

The transmission characteristics of each filter of this rotary filter 50 are shown in FIG. As shown in this figure, in this example, the filter that transmits B has a double transmission characteristic that also transmits wavelength region B' near 800 nm in the infrared band, and the filter that transmits G has a double transmission characteristic that also transmits wavelength region B' near 800 nm in the infrared band. It has a double transmission characteristic that also transmits the wavelength region G' of about 900 nm or more.

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

Further, a bandpass filter turret 51 is disposed on the illumination optical path between the rotary filter 50 and the incident end of the light guide 14. As shown in FIG. 2, this bandpass filter turret 51 includes five types of filters 51a and 51, each having different bandpass characteristics.
b, 51c.

51d and 51e are arranged along the circumferential direction. The transmission characteristics of each of the filters 51a to 51e are shown in FIGS. 7 to 11.

That is, as shown in FIG.
It transmits a narrow band centered at 69 nm and a narrow band centered at 650 nm. As shown in FIG. 8, the filter 51b has a narrow band centered at 805 nm and a narrow band centered at 900 nm.
Transmits wavelengths of m or more. As shown in FIG. 9, the filter 51c transmits a narrow band near 580 nm, a narrow band near 650 nm, and a narrow band near 800 nm. As shown in FIG. 10, the filter 51d transmits a band having a width of about 80 nm centered at about 400 nm. Further, as shown in FIG. 11, the filter 51e has approximately 40
Transmits visible band from 0 to 750 nm.

The bandpass filter turret 51 is rotated by a motor 52 whose rotation is controlled by a filter switching device 55.

Further, the filter switching device 55 is controlled by a control signal from the switching circuit 43. Then, by selecting the observation wavelength by the switching circuit 43, the bandpass filter turret 51
Behind each of the filters 51a to 51e, the switching circuit 4
The motor 52 is rotated so that the filter corresponding to the observation wavelength selected in step 3 is interposed on the illumination optical path, and the position of the bandpass filter turret 51 in the rotational direction is changed.

The light transmitted through the rotary filter 50 and separated in time series into light in each wavelength region of R, G, and B is further transmitted through a selected filter of the band-pass filter turret 51 and sent to the light guide. The light enters the incident end of the light guide 14, is guided to the tip 9 through the light guide 14, and is emitted from the tip 9 to illuminate the observation site.

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. A driving pulse from the driver circuit 31 in the video processor 6 is applied to the solid-state imaging collector 16 via the signal line 126,
Reading and transfer are performed by this drive pulse. The video signal read out from the solid state element 16 is input to a preamplifier 32 provided in the video processor 6 or in the electronic endoscope 1 via the signal line 27. . The video signal amplified by the preamplifier 32 is input to the GJ1 processing circuit 33, subjected to signal processing such as γ correction and white balance, and converted into a digital signal by the A/D converter 34. This digital video signal is selected by a select circuit 35 such as red (R), green (
Three memories (1) 3 corresponding to each color: G) and blue (B)
6a, Me-EIJ (2) 36b, Me-EIJ (
3) It is designed to be selectively stored in 36c.

hl memo') (1) 36a, me-f:') (2>3
6b.

The memory (3) 36c is simultaneously read out, converted into an analog signal by the D/A converter 37, and R, G
, is output as a B color signal, and is also input to an encoder 38, from which it is output as an NTSC composite signal.

The R, G, and B color signals or the NTSC signal are input to a color monitor 7, and the color monitor 7 displays the observed region in color.

Further, a timing generator 42 is provided in the video processor 6 to generate timing for the entire system, and the timing generator 42 controls the motor drivers 25 . Driver circuit 31. Each circuit, such as the select circuit 35, is synchronized.

In this embodiment, when the filter switching device 55 is controlled by the switching circuit 43 and one of the filters 518 to 51e of the bandpass filter turret 51 is selectively inserted into the illumination optical path, the selection By the filter,
The wavelength range of the light transmitted through the rotating filter 5O is further restricted.

When filter 51a is selected, 650
A narrow band centered at 569 nm is transmitted, and a narrow band centered at 569 nm is transmitted at the timing when the G transmission filter is inserted in the illumination optical path.

These two narrow band lights are irradiated onto the subject at the R and G timings, respectively, and the subject image created by this illumination light is
The image is imaged by the solid-state imaging element 16. And the above 2
Images in two wavelength ranges are output as R and G images, respectively.

By the way, Figure 4 shows the oxygen saturation of hemoglobin (80
Also written as 2. ) shows changes in blood absorbance (scattered reflection spectrum) due to changes in S02.
There is little change in blood absorbance due to changes in blood (569nm
(the wavelength is small compared to the degree of change in the vicinity).

Therefore, the blood flow rate in the mucous membrane can be observed from the difference in absorbance at these two wavelengths. As can be seen from FIG. 4, the wavelength at which the absorbance of blood hardly changes due to a change in 802 is 548 nm instead of 569 nm.
．． 5 nm or 586 nm may also be used.

Also, when the filter 51b is selected, the rotating filter 50
When the 8 transmission filter is inserted in the illumination optical path, a narrow band centered on 805 nm is transmitted, and when the G transmission filter is inserted in the illumination optical path, a band of 900 nm or more is transmitted.

The light in these two bands is irradiated onto the subject at timings B and G, respectively, and an image of the subject based on this illumination light is captured by the solid-state image sensor 16.

The images in the two wavelength ranges are B, respectively.

It is output as a G image.

By the way, ICG (Indocy), which is an infrared absorbing dye,
anine green, indocyanine green)
Blood mixed with Q has a maximum absorption at 805 nm, and almost no change in absorption rate is observed above 9 Q Q nm. Therefore, for example, the above CG is mixed into the blood by static injection, and the 805 nm and 900 nm
Images in the wavelength range of nm or more make it possible to observe the state of blood vessel running under the mucosa. That is, by using infrared light that has good tissue penetration, the light can reach deep into the tissue, while images in the 805 nm wavelength range show shadows in blood vessels. Therefore, this 805n
By taking the difference between the image in the wavelength range of m and the image in the wavelength range of 900 nm or more, it becomes possible to visualize the running state of blood vessels with good contrast.

Also, when the filter 51C is selected, the rotating filter 50
When the R transmission filter is inserted into the illumination optical path, a narrow band around 650 nm is transmitted, when the G transmission filter is installed in the illumination optical path, a narrow band around 580 nm is transmitted, and when the B transmission filter is installed in the illumination optical path, a narrow band around 580 nm is transmitted. A narrow band around 80 Qnm is transmitted at the timing when it is inserted in the optical path. This 3
The two narrow-band lights are irradiated onto the subject at the respective R, G, and B timings, and the subject image based on this illumination light is captured by the solid-state image sensor 16. Images in the three wavelength ranges are output as R, G, and B images, respectively.

By the way, Fig. 5 shows the spectral characteristics of oxy (oxidized) hemoglobin and deoxy (reduced) hemoglobin in order to show the change in the absorbance of blood due to the change in 802. and 800nm
31 is a region where the absorbance of blood hardly changes due to a change in 302, and near 650 nm is a region where the absorbance of blood changes due to a change in SO2. Therefore, changes in SO2 can be observed using images in these three wavelength regions.

Also, when the filter 51d is selected, the rotating filter 50
At the timing when the 0B transmission filter is inserted in the illumination optical path, a band around 400 nm is transmitted.

This band of light is irradiated onto the subject at timing B,
A subject image created by this illumination light is captured by the solid-state imaging device 16. Then, an image in this wavelength range is output as a B image.

As shown in FIG. 5, near 400 nm is a region where the absorbance Q of hemoglobin is large. Therefore, this 400nm
The hemoglobin distribution on the mucosal surface can be observed with good contrast using images in nearby wavelength ranges.

Also, when the filter 51e is selected, the rotating filter 50
The transmission wavelength range of the B and G transmission filters is limited to only visible light, and the subject is irradiated with regular R, G, and B light sequentially, and the subject image created by this illumination light is captured by the solid-state image sensor 16.
imaged by.

Therefore, normal color images in the visible band can be observed.

Further, the wavelength range is limited by each filter of the bandpass filter turret 51, and the wavelength range is R, G.

By processing the image signal assigned to the above in a signal processing circuit 60 as shown in FIG. 12, it is possible to obtain an image 302 or an image showing the amount of hemoglobin.

The signal processing circuit 60 has three selectors 61a, 61b, and 61c each with three inputs and one output, and an image signal corresponding to each wavelength is applied to each input of each selector. . Furthermore, each of the selectors selects and outputs image signals corresponding to mutually different wavelengths.

The output of each selector is sent to an inverse γ correction circuit 62.
a, 62b, and 62c, and since γ correction has already been performed by the video processor 6, inverse γ correction is performed to restore the original value.

The outputs of the inverse γ correction circuit are input to level adjustment circuits 63a, 63b, and 63c, respectively. The level of this level adjustment circuit is adjusted by a level adjustment control signal from a level adjustment control signal generation circuit 64, and the three level adjustment circuits 63 perform overall level adjustment.

Furthermore, since the vertical axis of a diagram showing changes in blood absorbance due to changes in oxygen saturation, such as in FIG. 5, is a log axis, the output of the level adjustment circuit is
7'/Pro 5a, 65b, and 65c perform logarithmic transformation.

Two of the three log amplifiers 10q amplifier 65a,
The output of 65b is input to a differential amplifier 66a, and the difference between the image signals corresponding to the two wavelengths is calculated. Similarly, two 100 amplifiers 65b, 65
The output of signal c is input to a differential amplifier 66b, and the difference between image signals corresponding to two wavelengths in other combinations is calculated.

Filter 51 of the bandpass filter turret 51
When G7/1 is selected, the differential amplifier 66a,
66b, an image signal corresponding to an area where the absorbance of blood hardly changes due to a change in 802;
The difference in image signals corresponding to areas where the absorbance of blood changes due to changes in blood is calculated by 1, and from this difference, it is possible to know how much oxygen has dissolved in the subject, that is, the oxygen saturation level. .

The outputs of the differential amplifiers 66a and 66b are oxygen saturation S
It is used to calculate O2 and is input to the divider 67,
By performing a predetermined calculation with this divider 67, when the filter 51C is selected, the above-mentioned value 802 is obtained. Further, the output of the differential amplifier 66b is transmitted to the filter 51.
a, 51b.

When 51d is selected, the blood flow rate.

Observe changes in blood vessel running status and hemoglobin amount.

Used for measurement. The output of the filter remover 67 and the output of the differential amplifier 66b are input to a two-man operated selector 68, which outputs one of a signal indicating S02 and a signal indicating blood flow, the running state of blood vessels, and the amount of hemoglobin. is selectively output.

1) When the output signal of the η selector 6B is used for measurement, it is taken out as is, but when it is to be displayed, it is subjected to γ correction again by the γ correction circuit 69 and output to the monitor.

Although the signal processing circuit 60 shown in FIG. 12 performs calculations using hardware, the processing may also be performed using software (that is, a microcomputer).

As described above, in this embodiment, by selectively interposing one of the filters 51a to 51e of the bandpass filter turret 51 in the illumination optical path, normal images,
It is also possible to switch and observe images showing changes in hemoglobin acid saturation, blood flow, blood vessel running conditions, hemoglobin amount, etc. in blood.

13 to 15 relate to the second embodiment of the present invention,
FIG. 13 is a block diagram showing the configuration of the endoscopic m device, and FIG.
The figure is an explanatory diagram showing a color filter array, and FIG. 15 is an explanatory diagram showing the transmission wavelength range of each filter of the color filter array.

This embodiment shows an example in which a simultaneous method is used as a color imaging method.

As shown in FIG. 13, the electronic endoscope 101 has an objective lens system 108 at the distal end of the insertion section, and a color filter array 102 is provided on the front surface at the imaging position of the objective lens system 108. A solid-state image carrier 103 is provided.

As shown in FIG. 14, the color filter array 102 is configured by arranging filters in a mosaic pattern that transmit light in the green (G), cyan (Cy), and yellow (Ye) wavelength ranges. . Furthermore, as shown in FIG. 15, in this embodiment, the filter that transmits and covers Cy is s in the infrared band.
It has a double transmission characteristic that also transmits the wavelength region Cy' near oom, and the filter that transmits G has a wavelength range of about 9 in the infrared band.
It has a double transmission characteristic that transmits the wavelength region G' of 00 nm or more.

Further, a light source unit 104 built into the video processor 6 includes a lamp 1 that emits light in a wide range from visible to infrared light.
05, and the light emitted from this lamp 105 is condensed by a lens 106 and made incident on the incident end of a light guide 107.

In this embodiment, the lens 106 and the light guide 107
A bandpass filter turret 51 similar to that of the first embodiment is disposed between the input end and the input end. Similar to the first embodiment, this bandpass filter turret 51 is rotated by a motor 52 whose rotation is controlled by a filter switching device 55, and one of the filters 518 to 51e is selectively interposed in the illumination optical path. It is now equipped.

The object illuminated by the illumination light is focused on the imaging surface of the solid-state image sensor 103 by the objective lens 108. that time,
The colors are separated into G, Cy, and Ye by the color filter array 102, but the bandpass filter turret 5
The wavelength is limited by 1.

The solid-state image sensor 103 is read by applying a drive signal from the driver 120. The solid-state image sensor 103
After being amplified by a preamplifier 122, the output signal of
123, 124 and band pass filter (BPF) 12
5 is passed.

The LPFs 123 and 124 are, for example, 3M)-1z.

The signals that pass through these are divided into a high-frequency luminance signal YH and a low-frequency luminance signal YL, and are sent to process circuits 126 and 1, respectively.
27, and γ correction and the like are performed. The high-frequency side luminance signal Y[+ passed through the process circuit 126 is subjected to horizontal contour correction, horizontal aberration correction, etc. in a horizontal correction circuit 128, and then inputted to a color encoder 129.

In addition, the low frequency side luminance signal Y passing through the process circuit 127
L is input to the matrix circuit 131 and also to the correction circuit 133, where tracking correction is performed.

On the other hand, BPF12 with a passband of 3.58±0.5MHz
5, the C color signal component is extracted, and this color signal component is 1
The signal is input to an HDL (IH delay line) 134, an adder 135, and a subtractor 136, and color signal components B and R are separated and extracted. In this case, the output of the 1HDL 134 is processed by the process circuit 127 and further processed by the vertical correction circuit 137.
The mixer 138 mixes the vertical aperture-corrected low-frequency luminance signal @YL, and this mixed output is sent to the adder 135.
and is input to the subtracter 136. And adder 135
The color signal B of the subtractor 136 and the color signal R of the subtractor 136 are input to the γ correction circuits 141 and 142, respectively, and are γ corrected using the low frequency side luminance signal YL passed through the correction circuit 133. 144, demodulated color signals B and R are input to the matrix circuit 131. This matrix circuit 131 generates a color difference signal R-
Y, B-Y are generated and the simulated color encoder 129
A luminance signal obtained by mixing luminance signals YH and YL and a chroma signal obtained by orthogonally modulating the color difference signals R-Y and B-Y using subcarriers are mixed (further superimposed with a synchronization signal (not shown)). , a composite video signal is output from the NTSC output terminal 145. The image signal outputted from the output terminal 145 displays the observed region in color.

Note that the driver 120 receives a synchronization signal from the synchronization signal generation circuit 152, and outputs a drive signal synchronized with this synchronization signal. Further, this synchronization signal generation circuit 152 is input to a pulse generator 153, and this pulse generator 153
outputs various timing pulses.

In this embodiment, as in the first embodiment, by selectively interposing one of the filters 51a to 51e of the bandpass filter turret 51 in the illumination optical path, normal images and blood Hemoglobin oxygen saturation, blood flow, and blood vessel running status.

It becomes possible to switch and observe each image showing changes in hemoglobin amount, etc.

Other functions and effects of the configuration 1 are the same as those of the first embodiment.

16 to 20 relate to the third embodiment of the present invention,
Fig. 16 is an explanatory diagram showing the transmission wavelength range of each filter of the rotating filter, Fig. 17 is an explanatory diagram showing the transmission wavelength range of one filter of the bandpass filter turret, and Fig. 18 is an explanatory diagram of the rotating filter and Fig. 17. Fig. 19 is an explanatory diagram showing the wavelength range of light transmitted through the filter of 1, Fig. 19 is an explanatory drawing showing the transmission wavelength range of the other filter of the bandpass filter turret, Fig. 20 is the rotating filter and the filter of Fig. 19. FIG. 3 is an explanatory diagram of the wavelength range of light transmitted through the .

In this embodiment, the characteristics of each filter of the rotary filter 50,
The configuration is similar to that of the first embodiment except that the characteristics of the bandpass filter in the bandpass filter turret 51 are different.

The transmission characteristics of the R, G, and B color separation filters provided in the rotary filter 50 are set as shown in FIG. 16. That is, in the visible light range, the light is separated into R, G, and B, and the B transmission filter has double transmission characteristics that also transmits the infrared light range B' of about 790 nm or more.

On the other hand, the bandpass filter turret 51 has a 17th
As shown in the figure, an infrared cut filter having infrared cut characteristics that blocks light in a wavelength region of approximately 750 nm or more;
As shown in FIG. 19, a filter having a bandpass characteristic that transmits light in a wavelength range of about 570 to 820 nm is provided.

In this embodiment, the transmitted wavelength of the light transmitted through the rotary filter 50 and color-separated in time series is limited by each wavelength range limiting filter provided on the bandpass filter turret 51.

That is, when an infrared cut filter with the characteristics shown in FIG. 17 is inserted in the illumination optical path, the light that goes far from the light guide 14 is divided into R, which divides the visible light range into three, as shown in FIG.
These are the characteristics of G and B. With this illumination light, a normal color image in the visible light range can be observed.

On the other hand, if a bandpass filter with the characteristics shown in FIG. 19 is inserted in the illumination optical path, the light reaching the light guide 14 will be
As shown in FIG. 20, the light is separated into two narrow wavelength bands in time series, one centered at about 580 nm and the other narrow band centered at about 800 nm.

As shown in Figure 20, the - side of the light is so
As shown in FIG. 5, the wavelength range centered on onm has a characteristic that its absorbance hardly changes due to changes in the oxygen saturation of hemoglobin, and images in this wavelength range are obtained as eight images. Furthermore, as shown in FIG. 5, the 16 wavelength range centered around 580 nm has a characteristic of high absorbance of hemoglobin, and an image in this wavelength range is obtained as a 0 image. Therefore, by processing the images in the two wavelength ranges in the signal processing circuit 60 shown in FIG. 12, a mucous membrane hemoglobin distribution image can be obtained. Furthermore, it is possible to switch between this mucous membrane hemoglobin distribution image and a normal color image.

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

21 to 26 relate to the fourth embodiment of the present invention,
Fig. 21 is an explanatory diagram showing the transmission wavelength range of each filter of the rotating filter, Fig. 22 is an explanatory diagram showing the transmission wavelength range of one filter of the bandpass filter turret, and Fig. 23 is an explanatory diagram showing the transmission wavelength range of each filter of the rotating filter and Fig. 22. An explanatory diagram showing the wavelength range of light transmitted through the filter, Figure 24 is an explanatory diagram showing the transmission wavelength range of one filter of the bandpass filter turret, and Figure 25 is an explanatory diagram showing the wavelength range of light transmitted through the rotating filter and the filter in Figure 24. FIG. 26 is an explanatory diagram showing the transmission characteristics of hemoglobin added with ICG.

In this embodiment, the characteristics of each filter of the rotary filter 50,
The configuration is similar to that of the first embodiment except that the characteristics of the bandpass filter in the bandpass filter turret 51 are different.

The transmission characteristics of the R, G, and B color separation filters provided in the rotary filter 50 are set as shown in FIG. 21. That is, in the visible light range, the light is divided into R, G, and B, and the B transmission filter has double transmission characteristics that also transmits the infrared light range B' of about 900 nm or more. Further, the R transmission filter is configured to transmit up to about 820 nm on the long wavelength side.

On the other hand, the bandpass filter turret 51 has a 22nd
As shown in the figure, an infrared cut filter having infrared cut characteristics that blocks light in a wavelength range of about 700 nm or more;
As shown in FIG. 24, a wavelength limiting filter is provided that transmits light in a wavelength range of about 790 nm or more.

In this embodiment, the transmitted wavelength of the light transmitted through the rotary filter 50 and color-separated in time series is limited by each wavelength range limiting filter provided on the bandpass filter turret 51.

That is, when an infrared cut filter with the characteristics shown in FIG. 22 is inserted in the illumination optical path, the light reaching the light guide 14 has R, which divides the visible light range into eight, as shown in FIG.
These are the characteristics of G and B. With this illumination light, a normal color image in the visible light range can be observed.

On the other hand, when a band-limiting filter with the characteristics shown in FIG. 24 is inserted in the illumination optical path, the light reaching the light guide 14 has a narrow band centered at about 8000 m and a narrow band centered at about 900 nm, as shown in FIG. 25. The light is separated into two wavelength ranges in time series.

An image in a wavelength range centered around about soon m is visualized as an R image, and an image in a wavelength range of about 900 nm or more is visualized as 8', that is, a B image.

It is known that when ICG (indocyanine green) is added to hemoglobin, which is the main pigment of blood in living organisms, the maximum absorbance peak is at 805 nm.
Further, the transmittance characteristics are as shown in FIG. 26.

Therefore, by inserting a wavelength limiting filter with the characteristics shown in Fig. 24 into the illumination optical path, it is possible to distinguish between the maximum peak wavelength range of light absorption when ICG is mixed into a living body, for example, by intravenous injection, and the wavelength range where there is no change in the approximate luminous intensity. It is possible to obtain an image based on

As described above, according to this embodiment, the difference between two images obtained by inserting a wavelength limiting filter having the characteristics shown in FIG. 24 into the illumination optical path can be calculated using, for example, the signal processing circuit 60 shown in FIG. By detecting blood vessels on the mucosa and under the mucosa, which are difficult to observe with visible light, it is possible to extract images with high contrast, and it is also possible to detect submucosal muscles, which are difficult to detect under the mucosa. This has the effect of dramatically improving observation ability.

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

In addition, 1st. In the third and fourth embodiments, the rotating filter 50 and the bandpass filter turret 51 may be located at opposite positions on the optical path.

27 to 29 relate to the fifth embodiment of the present invention,
Fig. 27 is an explanatory diagram showing the transmission wavelength range of each filter in the color filter array, Fig. 28 is an explanatory diagram showing the wavelength range of light transmitted through the color filter array and the filter in Fig. 17, and Fig. 29 is an explanatory diagram showing the wavelength range of light transmitted through the color filter array and the filter in Fig. 17. 20 is an explanatory diagram showing the wavelength range of light transmitted through the array and the filter of FIG. 19. FIG.

This embodiment has the same configuration as the second embodiment, except that the characteristics of each filter in the color filter array 102 and the characteristics of the bandpass filter in the bandpass filter turret 51 are different.

The transmission characteristics of the color filter array 102 are as follows:
The settings are as shown in the figure. That is, in the visible light range, the colors are separated into Cy, G, and Ye, and the Cy transmission filter transmits infrared light of about 790 nm or more II! It has a double transmission characteristic that also transmits tcy-.

The arrangement of the color filter array 102 is, for example, as shown in FIG. 14.

On the other hand, the bandpass filter turret 51 has a 17th
As shown in the figure, an infrared cut filter having infrared cut characteristics that blocks light in a wavelength region of approximately 750 nm or more;
As shown in FIG. 19, a filter having a bandpass characteristic that transmits light in a wavelength range of about 570 to 820 nm is provided.

In this embodiment, in the case of normal observation, the filter switching device 55 inserts an infrared cut filter having the characteristics shown in FIG. 17 into the illumination optical path. Then, due to this filling,・
The transmission wavelength range of the color filter array 102 is limited, and the colors are separated into Cy, G, and Ye as shown in FIG. 28. Then, a video signal is outputted in the same manner as in the second embodiment, and a normal color image in the visible light range can be observed.

On the other hand, when a bandpass filter with the characteristics shown in FIG. 19 is inserted in the illumination optical path, as shown in FIG.
It is color-separated into two narrow bands of wavelengths: a narrow band centered at , and a narrow band centered at about 8000 m. And the second
Since the same signal processing as in the example is performed, the image in the wavelength range centered around 580 nm transmitted through the Cy and G filters is visualized as a 0 image, and the image in the wavelength range of Cy′, which is the double transmission region of Cy, is visualized as a 0 image. Since light passes only through the Cy transmission filter, an image in this wavelength range is visualized as a Bji image.

As described above, according to this embodiment, the signal processing circuit 60 shown in FIG. 12 is used to process images in the two wavelength ranges shown in FIG. 29. l! By doing so, the same effects as in the third embodiment can be obtained in a simultaneous manner.

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

30 and 31 relate to the sixth embodiment of the present invention, FIG. 30 is an explanatory diagram showing the transmission wavelength range of each filter of the color filter array, and FIG. 31 is a color filter array and the filter of FIG. 24. FIG. 2 is an explanatory diagram showing the wavelength range of light transmitted through the .

This embodiment has the same configuration as the second embodiment, except that the characteristics of each filter in the color filter array 102 and the characteristics of the bandpass filter in the bandpass filter turret 51 are different.

The transmission characteristics of the color filter array 102 are as follows:
The settings are as shown in the figure. That is, in the visible light range, the colors are separated into Gy, G, and Ye, and the Cy transmission filter has double transmission characteristics that also transmits the infrared light range Cy' of about 900 nm or more.

Further, the Ye transmission filter is designed to transmit up to about 820 nm on the long wavelength side.

On the other hand, the bandpass filter turret 51 has a 22nd
As shown in the figure, an infrared cut filter having infrared cut characteristics that blocks light in a wavelength range of about 700 nm or more;
As shown in FIG. 24, a wavelength limiting filter is provided that transmits light in a wavelength range of about 790 nm or more.

In this embodiment, in the case of normal observation, by interposing an infrared cut filter having the characteristics shown in FIG. 22 in the illumination optical path, Cy ,
The colors are separated into G and Ye, allowing normal color images to be observed in the visible light range.

On the other hand, if a wavelength limiting filter with the characteristics shown in Fig. 24 is inserted in the illumination optical path, two wavelength ranges, a narrow band centered at about 800 nm and a wavelength range of about 9000 m or more, will be produced as shown in Fig. 31. Separated by color.

The light in the wavelength range centered around 800 nm is Ye
Since the light is only received by art trees that are compatible with transparent and filter filters,
Images in this wavelength range are visualized as 8 images, and light in the wavelength range of about 900 nm or more is transmitted only through the Cy-transmission filter, which is the Cy double transmission region. Images in this wavelength range are visualized as eight images.

As described above, according to this embodiment, the same effects as in the fourth embodiment can be obtained by processing images in two wavelength ranges shown in FIG. 31 using the Shintan processing circuit 60 shown in FIG. 12. However, it is possible to achieve 1 wattage using the simultaneous method.

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

Note that the present invention is not limited to the above-mentioned embodiments, and for example, the bandpass filter turret 51 as a wavelength limiting means.
The transmission characteristics and number of each filter can be set arbitrarily.

Furthermore, as the wavelength v1 limiter, a plurality of filters having different transmission characteristics may be provided in the optical path so as to be insertable and removable. Further, the wavelength limiting means may be provided in the front of the light guide output end, in the imaging optical system, in front of the solid-state image sensor, in the middle of the light guide, or on the illumination optical path or observation optical path leading to the image carrying means. You can set it up anywhere.

Further, the present invention is not limited to the one that receives reflected light from the object to be observed, but may be one that receives light that has passed through the object to be observed.

Furthermore, the present invention is applicable not only to electronic endoscopes having a solid-state image sensor at the distal end of the insertion section, but also to the eyepiece of an endoscope capable of visual observation such as a fiberscope, or to be replaced with the eyepiece. The present invention can also be applied to an endoscope device that is used by connecting a television camera.

[Effects of the Invention 1] As explained above, according to the present invention, by inserting and removing the wavelength υ1 limiting means on the illumination optical path or observation optical path leading to the m-image means, it is possible to obtain an image in the visible region within the shell; This has the effect that images in a specific wavelength range can be selectively obtained.

[Brief explanation of the drawing]

1 to 12 relate to a first embodiment of the present invention, in which FIG. 1 is a block diagram showing the configuration of an endoscope device, FIG. 2 is an explanatory diagram showing a bandpass filter turret, and FIG. A side view showing the entire endoscope device, Figures 4 and 5 are explanatory diagrams showing changes in blood absorbance due to changes in oxygen saturation of hemoglobin, and Figure 6 shows the transmission wavelength range of each filter of the rotating filter. 7 to 11 are explanatory diagrams showing the transmission wavelength range of each filter of the bandpass filter turret. FIG. 12 is a block diagram showing a processing circuit for determining hemoglobin dissemination and oxygen saturation. , FIG. 13 to FIG. 15 relate to a second embodiment of the present invention, FIG. 13 is a block diagram showing the configuration of an endoscope device, FIG. 14 is an explanatory diagram showing a color filter array, and FIG. 15 is a block diagram showing the configuration of an endoscope device. An explanatory diagram showing the transmission wavelength region of each filter of the color filter array, FIGS. 16 to 20 relate to the third embodiment of the present invention, and FIG. 16 shows the transmission wavelength region of each filter of the rotating filter. 17 is an explanatory diagram showing the transmission wavelength range of one filter of the band-pass filter turret; FIG. 18 is an explanatory diagram showing the wavelength range of light transmitted through the rotating filter and the filter in FIG. 17; FIG. The figure is an explanatory diagram showing the transmission wavelength range of another filter of the band-pass filter turret, Fig. 20 is an explanatory diagram showing the wavelength range of light transmitted through the rotating filter and the filter in Fig. 19, and Figs. FIG. 26 relates to the fourth embodiment of the present invention, FIG. 21 is an explanatory diagram showing the transmission wavelength range of each filter of the rotating filter, and FIG.
Figure 2 is an explanatory diagram showing the transmission wavelength range of one filter of the bandpass filter turret i, Figure 23 is an explanatory diagram showing the wavelength range of light transmitted through the rotating filter and the filter in Figure 22, and Figure 24. is one of the bandpass filter turrets
Fig. 25 is an explanatory diagram showing the wavelength range of light transmitted through the rotating filter and the filter in Fig. 24, and Fig. 26 is an explanatory diagram showing the transmission characteristics of hemoglobin with ICG added. 27 to 29 relate to the fifth embodiment of the present invention, FIG. 27 is an explanatory diagram showing the transmission wavelength range of each filter of the color filter array, and FIG. FIG. 29 is an explanatory diagram showing the wavelength range of light transmitted through the filter in FIG. 29. FIG. 29 is an explanatory diagram showing the wavelength region of light transmitted through the color filter array and the filter in FIG. Regarding the sixth embodiment, FIG. 30 shows the transmission wavelength range of each filter of the color filter array.
The figure is an explanatory diagram showing the wavelength range of light transmitted through the color filter array and the filter of FIG. 24. 1... Electronic endoscope 6... Video processor 7... Monitor 15... Objective lens system 1
6... Solid-state positive image element 21... Lamp 50...
Rotating filter 51... Bandpass filter turret (nm) (nm) (nm) (nm) (nm) (nm) (nm) (nm) (nm) (nm) (nm) (nm) (nm) (nm) (nm) (nm) Fig. 10 WaJ & (nm) Fig. 11 TeE1. - ~ (nm) Fig. 14 Fig. 15 Growth (nm) 'R' (nm) Fig. 18 Fig. 19 Fig. 20 Mass M (nm) ffl& (nm) Uranaga (nm) Fig. 23 Bay 4% (nm) Wavelength (nm) Bay length (nm) iJ% (nm) Temperature (nm)

Claims (1)

[Claims] an endoscope having at least an imaging optical system; a color separation means for separating a subject image into images of a plurality of wavelength regions to obtain a color image; an image means for capturing images of each wavelength range separated by the means; and a part of the wavelength range separated by the color separation means, which is removably provided on the illumination optical path or observation optical path leading to the image capturing means. What is claimed is: 1. An endoscope apparatus comprising: a wavelength limiting means capable of transmitting the .