JP3583731B2 - Endoscope device and light source device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an endoscope apparatus that captures an image of a living tissue and performs signal processing.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, an endoscope apparatus that irradiates illumination light to obtain an endoscopic image in a body cavity has been widely used. In this type of endoscope device, an electronic endoscope having imaging means for guiding illumination light from a light source device into a body cavity by using a light guide or the like and capturing an image of a subject by return light thereof is used. An endoscope image is displayed on an observation monitor by performing signal processing on an imaging signal from an imaging unit, and an observation site such as an affected part is observed.
[0003]
When performing normal living tissue observation with an endoscope device, the light source device emits white light in the visible light region, and irradiates the subject with light in a sequential manner through a rotating filter such as RGB. A color image is obtained by synchronizing the return light by light with a video processor and performing image processing, or a color chip is arranged in front of the imaging surface of the imaging means of the endoscope, and the return light by white light is converted into RGB by the color chip. A color image is obtained by taking an image by separating and processing the image by a video processor.
[0004]
On the other hand, in living tissue, light absorption characteristics and scattering characteristics are different depending on the wavelength of light to be irradiated. In recent years, for example, it is possible to irradiate living tissue with infrared light as illumination light and observe deep tissue in the living tissue. Various infrared endoscope devices have been proposed.
[0005]
[Problems to be solved by the invention]
However, in the diagnosis of a living tissue, deep tissue information near the tissue surface is also an important observation target, but the infrared endoscope apparatus described above can only obtain deep tissue information deeper than the tissue surface.
[0006]
Further, when white light is radiated on living tissue as RGB plane sequential light by a rotation filter, since the wavelength range is different, an imaging signal by light of each color has different deep tissue information near the tissue surface of the living tissue. However, in order to make the endoscope image by the RGB plane sequential light into a more natural color image, white light is generally separated into RGB light whose wavelength ranges overlap each other.
[0007]
That is, in the overlapped RGB light, a wide depth of tissue information is captured in the imaging signal of light in each wavelength range, so that it is difficult to visually recognize desired deep tissue information near the tissue surface of the living tissue. There's a problem.
[0008]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an endoscope apparatus and a light source apparatus that can obtain tissue information at a desired deep portion near a tissue surface of a living tissue.
[0009]
[Means for Solving the Problems]
An endoscope apparatus according to the present invention includes an illumination light supply unit that supplies illumination light including a visible light region, an endoscope having an imaging unit that irradiates the illumination light onto a subject and captures the subject with return light, An endoscope apparatus comprising: a signal processing unit that performs signal processing on an imaging signal from the imaging unit.A plurality of the illumination lights are arranged so as to be arranged on an optical path from the illumination light supply means to the imaging means, and the tissue information of the tissue in the body cavity of the subject is separated at a layer level and can be visually recognized. A band limiting unit that limits a band of at least one wavelength region in the wavelength region to be narrow, and forms a band image of a discrete spectral distribution of a subject obtained from the narrow band light on the imaging unit. And
The light source device of the present invention is provided such that illumination light supply means for supplying illumination light in a plurality of wavelength regions including a visible light region, and to be arranged on an optical path of illumination light supplied from the illumination light supply means. A band in which the band of at least one wavelength region of the plurality of wavelength regions of the illumination light is limited to be narrowed, and a band image of a discrete spectral distribution of a subject obtained from the narrow band light is formed on the imaging unit. Limiting means, a normal observation mode for obtaining an image for normal observation based on the illumination light, and tissue information of a tissue in a body cavity of the subject from the band image of the discrete spectral distribution obtained by the band limiting means at a layer level. And control means for controlling the generation of the light having the discrete spectral distribution by the band limiting means based on a mode switching instruction for switching between a narrow band observation mode and a narrow band observation mode that can be visually recognized separately. The features.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0011]
1 to 33 relate to a first embodiment of the present invention, FIG. 1 is a configuration diagram showing a configuration of an endoscope device, FIG. 2 is a configuration diagram showing a configuration of a rotary filter of FIG. 1, and FIG. FIG. 4 is a diagram showing spectral characteristics of a first filter set of the rotary filter of FIG. 2; FIG. 4 is a diagram showing spectral characteristics of a second filter set of the rotary filter of FIG. 2; FIG. 6 is a diagram illustrating a layered structure of a living tissue to be observed, FIG. 6 is a diagram illustrating a state in which illumination light from the endoscope apparatus in FIG. 1 reaches a layered direction of the living tissue, and FIG. 7 is a first diagram in FIG. FIG. 8 is a diagram showing each band image by plane-sequential light transmitted through the second filter set of FIG. 4, and FIG. 9 is a diagram showing each band image by plane-sequential light transmitted through the filter set. FIG. 10 is a diagram for explaining dimming control according to the first embodiment of the present invention. FIG. 10 shows spectral characteristics of a first modification of the second filter set of the rotary filter in FIG. FIG. 11 is a diagram showing spectral characteristics of a second modification of the second filter set of the rotary filter of FIG. 2; FIG. 12 is a third modification of the second filter set of the rotary filter of FIG. FIG. 13 is a view for explaining the operation of the third modification of the second filter set of the rotary filter of FIG. 2, and FIG. 14 is a first example of the spectral distribution of the xenon lamp of FIG. FIG. 15 is a diagram showing a spectral characteristic of a fourth modified example of the second filter set of the rotating filter at the time of the spectral distribution of the xenon lamp of FIG. 14, and FIG. 16 is a second filter set of FIG. FIG. 17 is a diagram showing a spectral characteristic of living tissue illumination light according to a fourth modified example of FIG. 17, FIG. 17 is a diagram showing a second example of the spectral distribution of the xenon lamp of FIG. 1, and FIG. FIG. 19 is a view showing an example, and FIG. FIG. 20 is a diagram showing the spectral characteristics of the neutral density filter deposited on the fifth modified example of the second filter set of the rotary filter when the characteristic is shown in FIG. 18. FIG. 20 is a second filter on which the neutral density filter of FIG. 19 is deposited. FIG. 21 is a diagram showing the spectral characteristics of a fifth modification of the set, FIG. 21 is a configuration diagram showing the configuration of a first modification of the light source device of FIG. 1, and FIG. 22 is a configuration showing the configuration of the dimming rotation filter of FIG. FIG. 23 is a configuration diagram showing a configuration of a second modified example of the light source device of FIG. 1, and FIG. 24 is a diagram showing a dimming characteristic of a first dimming filter constituting the dimming filter of FIG. 25 is a diagram showing the dimming characteristics of the second dimming filter constituting the dimming filter of FIG. 23, FIG. 26 is a diagram showing the dimming characteristics of the dimming filter of FIG. 23, and FIG. 27 is a rotary filter of FIG. FIG. 28 is a diagram showing an example showing detailed spectral characteristics of the second filter set of FIG. FIG. 29 is a diagram illustrating spectral characteristics of a sixth modification of the second filter set, FIG. 29 is a diagram illustrating a configuration of a main part of a modification of the video processor in FIG. 1, and FIG. 30 is a diagram illustrating the operation of the video processor in FIG. FIG. 31 is a second diagram for explaining the operation of the video processor of FIG. 29, FIG. 32 is a diagram showing a seventh modification of the second filter set of the rotary filter of FIG. 2, and FIG. FIG. 33 is a diagram illustrating spectral characteristics of a seventh modification of the second filter set in FIG. 32.
[0012]
As shown in FIG. 1, an endoscope apparatus 1 according to the present embodiment includes an electronic endoscope 3 having a CCD 2 as an imaging unit that is inserted into a body cavity to image a tissue in the body cavity, and illuminates the electronic endoscope 3. A light source device 4 for supplying light and an imaging signal from the CCD 2 of the electronic endoscope 3 are signal-processed to display an endoscope image on an observation monitor 5 or to encode the endoscope image and image filing as a compressed image. And a video processor 7 for outputting to the device 6.
[0013]
The light source device 4 includes a xenon lamp 11 that emits illumination light, a heat ray cut filter 12 that blocks a heat ray of white light, an aperture device 13 that controls the amount of white light that passes through the heat ray cut filter 12, and a light source that emits illumination light. A rotary filter 14 for converting the light into light in a plane-sequential manner; a condenser lens 16 for collecting the light in a plane-sequential manner via the rotary filter 14 on an incident surface of a light guide 15 disposed in the electronic endoscope 3; And a control circuit 17 for controlling the rotation of.
[0014]
As shown in FIG. 2, the rotary filter 14 is formed in a disc shape and has a double structure with the center as a rotation axis, and the outer diameter portion has an overlap suitable for color reproduction as shown in FIG. The R1 filter 14r1, the G1 filter 14g1, and the B1 filter 14b1 constituting a first filter set for outputting plane-sequential light having the obtained spectral characteristics are arranged, and a desired deep layer as shown in FIG. An R2 filter 14r2, a G2 filter 14g2, and a B2 filter 14b2, which constitute a second filter set for outputting narrow-band plane-sequential light having discrete spectral characteristics from which tissue information can be extracted, are arranged. As shown in FIG. 1, the rotary filter 14 is driven by a control of a rotary filter motor 18 by a control circuit 17, and is rotated, and is moved in a radial direction (movement perpendicular to the optical path of the rotary filter 14; The first filter set or the second filter set of the filter 14 is selectively moved on the optical path) by the mode switching motor 19 according to a control signal from a mode switching circuit 42 in the video processor 7 described later.
[0015]
Power is supplied from the power supply unit 10 to the xenon lamp 11, the aperture device 13, the rotary filter motor 18, and the mode switching motor 19.
[0016]
Returning to FIG. 1, the video processor 7 includes a CCD drive circuit 20 that drives the CCD 2, an amplifier 22 that amplifies an imaging signal obtained by capturing an image of a body cavity tissue by the CCD 2 via the objective optical system 21, and an imaging via the amplifier 22. A process circuit 23 that performs correlated double sampling and noise removal on the signal, an A / D converter 24 that converts an image signal that has passed through the process circuit 23 into digital signal image data, and an A / D converter 24. A white balance circuit 25 for performing a white balance process on the image data of FIG. 1, a selector 26 for synchronizing the frame-sequential light by the rotation filter 14, and synchronizing memories 27, 28, 29, and synchronizing memories 27, 28, 29. An image processing circuit 30 that reads out the stored image data of the frame sequential light and performs gamma correction processing, contour enhancement processing, color processing, and the like; D / A circuits 31, 32 and 33 for converting image data from the processing circuit 30 into analog signals, an encoding circuit 34 for encoding the outputs of the D / A circuits 31, 32 and 33, and control of the light source device 4 A timing generator 35 that inputs a synchronization signal synchronized with the rotation of the rotation filter 14 from the circuit 17 and outputs various timing signals to the respective circuits.
[0017]
Further, the electronic endoscope 2 is provided with a mode changeover switch 41, and an output of the mode changeover switch 41 is output to a mode changeover circuit 42 in the video processor 7. The mode switching circuit 42 of the video processor 7 outputs a control signal to the dimming circuit 43, the dimming control parameter switching circuit 44, and the mode switching motor 19 of the light source device 4. The dimming control parameter switching circuit 44 outputs dimming control parameters corresponding to the first filter set or the second filter set of the rotary filter 14 to the dimming circuit 43. The aperture control device 13 of the light source device 4 is controlled on the basis of the control signal and the dimming control parameter from the dimming control parameter switching circuit 44 to perform appropriate brightness control.
[0018]
Next, the operation of the thus configured endoscope apparatus of the present embodiment will be described.
[0019]
As shown in FIG. 5, the body cavity tissue 51 often has an absorber distribution structure such as a blood vessel different in the depth direction. Many capillaries 52 are mainly distributed near the surface layer of the mucous membrane, and in the middle layer deeper than this layer, a blood vessel 53 thicker than the capillaries is distributed in addition to the capillaries, and a thicker blood vessel 54 is further distributed in the deeper layer. become.
[0020]
On the other hand, the depth of the light in the depth direction of the light with respect to the tissue 51 in the body cavity depends on the wavelength of the light, and the illumination light including the visible region has a blue (B) color as shown in FIG. In the case of light with such a short wavelength, light can only reach the surface layer due to absorption and scattering characteristics of living tissue, and light is absorbed and scattered within the range of the depth, and light emitted from the surface is observed. Is done. In the case of green (G) light having a longer wavelength than blue (B) light, the light reaches deeper than the range where blue (B) light deepens, and is absorbed and scattered in that range and exits from the surface. Light is observed. Furthermore, red (R) light, which has a longer wavelength than green (G) light, reaches a deeper range.
[0021]
At the time of normal observation, the mode switching circuit in the video processor 7 is controlled by a control signal so as to be located on the R1 filter 14r1, the G1 filter 14g1, and the B1 filter 14b1, which are the first filter set of the rotary filter 14, on the optical path of the illumination light. The mode switching motor 19 is controlled.
[0022]
As shown in FIG. 3, the R1 filter 14r1, the G1 filter 14g1, and the B1 filter 14b at the time of normal observation of the body cavity tissue 51 are imaging signals picked up by the CCD 4 by the B1 filter 14b1 so that the respective wavelength ranges overlap. FIG. 7 (a) shows a band image having shallow-layer and middle-layer tissue information containing a large amount of tissue information in the shallow layer as shown in FIG. 7 (a). The image signal picked up by the CCD 4 by the G1 filter 14g1 is shown in FIG. 7 (b), a band image having shallow-layer and middle-layer tissue information containing a large amount of tissue information in the middle layer as shown in FIG. 7 (b) is captured. As shown in the figure, a band image having middle-layer and deep-layer tissue information including a large amount of tissue information at the deep layer is captured.
[0023]
Then, by synchronizing the RGB image signals with the video processor 7 and performing signal processing, it is possible to obtain an endoscope image having desired or natural color reproduction as the endoscope image.
[0024]
On the other hand, when the mode changeover switch 41 of the electronic endoscope 3 is pressed, the signal is input to the mode changeover circuit 42 of the video processor 7. The mode switching circuit 42 outputs a control signal to the mode switching motor 19 of the light source device 4 to move the first filter set of the rotary filter 14 on the optical path at the time of normal observation, and to light the second filter set. The rotary filter 14 is driven with respect to the optical path so as to be arranged on the road.
[0025]
The R2 filter 14r2, the G2 filter 14g2, and the B2 filter 14b2 at the time of narrow-band light observation of the tissue 51 in the body cavity by the second filter set are used to convert the illumination light into a narrow-band surface having discrete spectral characteristics as shown in FIG. In order to sequentially emit light, a band image having tissue information in a shallow layer as shown in FIG. 8A is captured in an image signal captured by the CCD 4 by the B2 filter 14b2, and the CCD 4 is captured by the G2 filter 14g2. A band image having tissue information in the middle layer as shown in FIG. 8B is taken as an image pickup signal picked up in FIG. 8B, and an image pickup signal picked up by the CCD 4 by the R2 filter 14r2 is taken as shown in FIG. A band image having tissue information at a deep level as shown is captured.
[0026]
At this time, as is apparent from FIGS. 3 and 4, the transmitted light amount by the second filter set is smaller than the transmitted light amount by the first filter set because the band becomes narrower. The circuit 44 outputs a dimming control parameter corresponding to the first filter set or the second filter set of the rotary filter 14 to the dimming circuit 43, so that the dimming circuit 43 controls the diaphragm device 13, and As shown in FIG. 9, for example, a linear aperture control line 61 by the aperture device 13 at the time of normal observation according to the set value Lx on a setting panel (not shown) of the video processor 7 is compared with the aperture device 13 at the time of narrow-band light observation. To control the light amount Mx according to the aperture control curve 62 corresponding to the set value Lx.
[0027]
Specifically, in conjunction with the change from the first filter set to the second filter set, the aperture level value corresponding to the light amount set value Lx is changed from Mx1 to Mx2 as shown in FIG. As a result, the aperture is controlled in the opening direction, and the filter operates so as to compensate for a decrease in the illumination light amount due to the narrow band of the filter.
[0028]
As a result, image data with sufficient brightness can be obtained even during narrowband light observation.
[0029]
As described above, in the present embodiment, at the time of normal observation of the tissue 51 in the body cavity, the mode switch 41 is depressed as necessary to switch the first filter set of the rotary filter 14 to the second filter set. It is possible to shift to narrow-band light observation, and in this narrow-band light observation, tissue information of each layer of the body cavity tissue 51 can be obtained as an imaging signal in a separated state by the second filter set of the rotary filter 14, In addition, since an imaging signal of an appropriate light amount can be obtained by controlling the diaphragm device 13, the tissue information of each layer of the tissue 51 in the body cavity, which is important for diagnosis, can be separated at the layer level and can be reliably viewed. The state of the internal tissue 51 can be diagnosed more accurately.
[0030]
The second filter set is a filter set (R2 filter 14r2, G2 filter 14g2, B2 filter 14b2) as shown in FIG. 4 for the spectral characteristics of the illumination light, but is not limited to this. As a first modification of the first embodiment, a filter set that generates narrow band plane-sequential light having discrete spectral characteristics as shown in FIG. In the filter set of the first modification, the G filter and the R filter are the same as the G filter and the R filter of the first filter set, and only the B filter is narrowed. This is particularly suitable when attention is paid to a capillary structure or the like near the surface of a living tissue, and other band images may be the same as conventional images.
[0031]
The filter characteristics are not limited to the visible light range. As a second modified example of the second filter set, the illumination light is converted into narrow band plane sequential light having discrete spectral characteristics as shown in FIG. A filter set may be used. The filter set according to the second modified example sets B in the near-ultraviolet region and R in the near-infrared region in order to observe irregularities on the surface of the living body and the absorber near the extremely deep layer. This is suitable for obtaining image information that cannot be obtained.
[0032]
Further, as a third modification of the second filter set, as shown in FIG. 12, instead of the G filter, a filter set including two filters that are close to B2a and B2b in a short wavelength range may be used. This is suitable for imaging a subtle difference in scattering characteristics rather than absorption characteristics by utilizing the fact that the wavelength band in the vicinity extends only to the vicinity of the very surface layer of the living body. In other words, as shown in FIG. 13, if a filter is formed at a position where the scattering characteristics change greatly so that the absorption characteristics of the living body become substantially equal at the center wavelengths of B2a and B2b, the near-surface scattering characteristics can be imaged. It is suitable for. Medically, it is supposed that the present invention is used for discriminating and diagnosing diseases such as early cancer, which have disordered cell arrangement near the mucosal surface layer.
[0033]
Generally, a xenon lamp or the like is often manufactured so as to block ultraviolet light. FIG. 14 shows an example of the spectral distribution of the illumination light source. Therefore, in the B region of the second filter set, even if the short wavelength side is set as an open characteristic as a transmission region as shown in FIG. 15, the characteristic as shown in FIG. Band illumination light characteristics can be realized. In addition, in the case of manufacturing an optical filter, it is often the case that a multilayer interference film filter is usually deposited, and in the manufacturing method, in order to narrow the spectral transmittance characteristic, a number of layers must be deposited, Therefore, there is a problem that the cost is increased and the thickness of the filter is increased. However, by using the lamp characteristics to make one side open, the manufacturing cost and the thickness can be reduced.
[0034]
When the spectral distribution of the light source is as shown in FIG. 17 and the spectral sensitivity characteristic of the CCD is as shown in FIG. 18, the rotation filter 14 is switched from the first filter set to the second filter set. In conjunction with this, light control is set brighter to compensate for the decrease in light amount due to the narrowing of the band. As a result, although the B2 band image is appropriate, the G2 band image and the R2 band image may become slightly saturated. Alternatively, the white balance is adjusted by the white balance circuit 25 in FIG. 1, and as a result, the B2 band image having a low brightness level is excessively amplified by the second filter set, the light source device, and the CCD sensitivity characteristic, and the SN is poor. An image will be observed.
[0035]
Therefore, it is necessary to control not only the band characteristic but also the peak transmittance characteristic in consideration of the spectral distribution of elements that affect the system spectral sensitivity, such as the light source spectral distribution characteristic and the CCD spectral sensitivity characteristic.
[0036]
Therefore, in consideration of system spectral sensitivity characteristics and dimming characteristics other than the filter, as a fifth modified example of the second filter set, a dimming as shown in FIG. 19 for obtaining an image of appropriate brightness. A neutral density filter having the characteristics a and b may be formed by vapor deposition or bonding to the R2 filter 14r2 and the G2 filter 14g2 of the rotary filter 14. As a result, a narrow band filter set having the characteristics shown in FIG. 20 can be obtained. Thus, not only the band characteristics. The transmittance characteristics can also be set appropriately, and an image with optimal brightness can be observed in each band.
[0037]
Considering the spectral distribution of factors that affect system spectral sensitivity, such as light source spectral distribution characteristics and CCD spectral sensitivity characteristics, as a method of controlling not only band characteristics but also peak transmittance characteristics, as described above, a neutral density filter is used. As shown in FIG. 21, in addition to vapor deposition or bonding to the R2 filter 14r2 and the G2 filter 14g2 of the rotary filter 14, a first modified example of the light source device 4 is provided separately from the rotary filter 14 on the optical path. 61 may be provided. As shown in FIG. 22, the dimming rotary filter 61 has the same double structure as the rotary filter 14 (see FIG. 2), and the R1 filter 14r1, the G1 filter 14g1, and the B1 filter 14b1, Each part corresponding to the B2 filter 14b2 is a transmission part, and only the parts corresponding to the R2 filter 14r2 and the G2 filter 14g2 are the dimming filters 62 and 63 for dimming the respective band lights. The dimming rotation filter 61 is driven to rotate by a rotation filter motor 64 based on a control signal of the control circuit 17 similarly to the rotation filter 14, and is controlled by a mode switching motor 65 based on a control signal from the mode switching circuit 42. The radial direction can move perpendicular to the optical path, and the driving timing is synchronized with the rotation filter 14.
[0038]
As a method of controlling not only the band characteristic but also the peak transmittance characteristic in consideration of the spectral distribution of elements that affect the system spectral sensitivity, such as the light source spectral distribution characteristic and the CCD spectral sensitivity characteristic, as described above, As shown in FIG. 23, instead of the light source device provided with the rotation filter 61, a second modification of the light source device 4 is formed by combining a plurality of filters to form a neutral density filter 71 having a desired band transmittance from the mode switching circuit 42. Can be inserted into and removed from the optical path by the filter moving motor 72 on the basis of the control signal described above, and the drive is performed by removing the rotary filter 14 at the first filter and inserting it at the second filter. The neutral density filter 71 shown in FIG. 26 is formed by combining a first neutral density filter having the neutral density characteristics shown in FIG. 24 and a second neutral density filter having the neutral density characteristics shown in FIG. By providing optical characteristics, it is possible to control not only band characteristics but also peak transmittance characteristics.
[0039]
As an example of specific spectral characteristics of the R2 filter 14r2, the G2 filter 14g2, and the B2 filter 14b2, as shown in FIG. 27, the R2 filter 14r2 has a wavelength band including 600 nm and a half-width of 20 to 40 nm. The G2 filter 14g2 has a bandpass characteristic of a wavelength band including 540 nm and a half width of 20 to 40 nm, and the B2 filter 14b2 has a wavelength band of 420 nm and a bandpass characteristic of 20 to 40 nm. .
[0040]
With the spectral characteristics as shown in FIG. 27, observation with illumination light having a narrow band characteristic including 420 nm, which is a band in which the absorption of blood in the visible light region is large, makes it possible to enhance the capillary structure on the mucosal surface. In addition to being able to reproduce in contrast, the distribution of the absorber in the biological mucosa in the depth direction can be reproduced in different colors, and it is possible to overview the relative position of the absorber in the depth direction such as a blood vessel image.
[0041]
Further, as a modified example of the R2 filter 14r2, the G2 filter 14g2, and the B2 filter 14b2, a G ′ filter 14g ′, a G ″ filter 14g ″ and a B2 filter 14b2 having spectral characteristics as shown in FIG. 28 may be used. The G ′ filter 14g ′ has a band-pass characteristic having a wavelength band including 550 nm and a half-value width of 20 to 40 nm, the G ″ filter 14g ″ has a wavelength band including 500 nm and a band-pass characteristic having a half-value width of 20 to 40 nm, Further, the B2 filter 14b2 has a bandpass characteristic of a wavelength band including 420 nm and a half width of 20 to 40 nm.
[0042]
With the spectral characteristics shown in FIG. 28, observation with illumination light having a narrow band characteristic including 420 nm, which is a band in which the absorption of blood in the visible light region is large, allows a high capillary structure on the mucosal surface to be observed. In addition to being able to reproduce with contrast, by providing band-pass light near 500 nm as an adjacent wavelength band, image reproduction specialized for the structure of the mucosal surface can be realized.
[0043]
In conjunction with the change from the first filter set to the second filter set, the aperture level value corresponding to the light amount set value Lx is changed from Mx1 to Mx2 as shown in FIG. Although the aperture is controlled in the opening direction and the filter operates so as to compensate for the decrease in illumination light amount due to the narrow band of the filter, the irradiation light amount may be increased by extending the exposure time.
[0044]
However, the living body that is the subject is not necessarily stationary, but involves peristalsis and pulsation.If a freeze operation is performed during image observation, the image will move during exposure to the CCD. Increasing the irradiation light amount by extending the time causes a problem that image blur increases.
[0045]
Therefore, as a modified example of the video processor 7, as shown in FIG. 29, pre-freeze memories 200, 201, and 202 for always recording images for several frames are provided at the subsequent stage of the synchronization memories 27, 28, and 29. And a motion detection circuit 210 for comparing the image data between fields based on the output signals of the synchronization memories 27, 28 and 29 and the input signal of the selector 26 and detecting the motion.
[0046]
With this configuration, when the mode switching instruction switch 41 provided on the electronic endoscope 3 is pressed, the mode switching circuit 42 controls the timing generator 35 and the control circuit 17 of the light source device 4 controls the exposure time. Of the rotating filter 14 is controlled so as to be twice as large as that during normal observation (the rotating speed of the rotating filter 14 in the second filter set is half the rotating speed of the first filter set).
[0047]
When the freeze switch 205 provided on the electronic endoscope 3 is pressed, for example, at the timing shown in FIG. 30 during normal observation and at the timing shown in FIG. , The motion is detected by comparing the image data obtained in Steps (1) and (2), and the updating of the image data recorded in the memories 200, 201, and 202 is controlled.
[0048]
More specifically, for example, the case of normal observation in FIG. 30 will be described. For example, the image data R0 of one field period stored in the synchronization memory 27 by the motion detection circuit 210 and the image of one field period input to the selector 26 The data G0 is compared (first comparison), and the image data G0 of one field period stored in the synchronization memory 28 and the image data B0 of one field period input to the selector 26 are compared (second comparison). If the mode switching circuit 42 determines that there is no motion, the mode switching circuit 42 controls the timing generator 35 to store the data in the memories 200, 201, 202 in the next field period (period * in the figure). The stored image data R0, G0, B0 are written.
[0049]
Also, as a result of the second comparison by the motion detection circuit 210, after it is determined that there is no motion, the image data B0 for one field period stored in the synchronization memory 29 and the one-field period input to the selector 26 The image data R1 is compared (third comparison), and if it is determined that there is no motion in the result of the third comparison, the mode switching circuit 42 controls the timing generator 35 to perform the next field period (in the figure, , The memories 200, 201, and 202 are updated, and the image data R1, G0, and B0 stored in the synchronization memories 27, 28, and 29 are overwritten.
As a result of the third comparison, if it is determined that there is a motion, the data is not updated in the above-mentioned * period, and the data recorded in the * period is held in the memories 200, 201, and 202.
[0050]
In this manner, the memories 200, 201, and 202 are sequentially updated in the next field. Note that the same update is performed on the memories 200, 201, and 202 as shown in FIG. 31 only by doubling the exposure time during narrow-band observation.
[0051]
When the freeze switch 205 provided on the electronic endoscope 3 is pressed, the mode switching circuit 42 controls the timing generator 35 to stop reading from the synchronization memories 27, 28, and 29, and the memory 200, The image data read from 201 and 202 is output to the image processing circuit 30.
[0052]
However, when there is no image data in the memories 200, 201, and 202, or immediately after the mode switching instruction switch 41 is pressed to switch to the second filter set of the rotation filter 14, the motion is detected by the motion detection circuit 210. Until the freeze switch 205 is pressed, reading from the synchronization memories 27, 28, and 29 is continued, and reading from the synchronization memories 27, 28, and 29 is stopped only after a motion is detected.
[0053]
By providing the memories 200, 201, and 202 and the motion detection circuit 210 as shown in FIG. 29, when the exposure time is extended during narrow-band observation, an image in which blurring of the image is minimized even when freeze is applied. Obtainable.
[0054]
By the way, in general, a fluorescence image of a living tissue by excitation light does not reflect the fine structure of the mucous membrane surface, but reveals the presence of a lesion that is hardly detectable by visible light. On the other hand, it is known that the fine structure of the mucosal surface such as a capillary blood vessel image is important information for differential diagnosis of a lesion. Therefore, by combining these two pieces of information and displaying them as an image, the diagnostic ability may be improved.
[0055]
Specifically, instead of the R2 filter 14r2, the G2 filter 14g2, and the B2 filter 14b2, as shown in FIG. 32, an F filter 14f for excitation light, and a second filter of a rotation filter including a G2 filter 14g2 and a B2 filter 14b2. Construct a filter set. Here, the spectral characteristics of the F filter 14f for the excitation light are as shown in FIG.
[0056]
When the living tissue is irradiated with the excitation light in a narrow band by the F filter 14f, fluorescence having a wavelength as shown in FIG. 33 is emitted from the living tissue. Therefore, it is possible to switch between normal observation in which color reproduction characteristics having broadband characteristics are emphasized as in the above-described embodiment and high-performance observation using an image in which fluorescence and narrow-band light are superimposed.
[0057]
As described above, it is possible to observe a lesion that is difficult to be detected by visible light using fluorescence observation and to perform detailed observation of the mucosal surface using narrow-band light, so that diagnostic performance can be improved.
[0058]
34 to 36 relate to the second embodiment of the present invention, FIG. 34 is a configuration diagram showing a configuration of an endoscope apparatus, FIG. 35 is a configuration diagram showing a configuration of a rotary filter of FIG. 34, and FIG. FIG. 35 is a diagram illustrating spectral characteristics of the color chip of FIG. 34.
[0059]
Since the second embodiment is almost the same as the first embodiment, only different points will be described, and the same components will be denoted by the same reference numerals and description thereof will be omitted.
[0060]
As shown in FIG. 34, in the electronic endoscope 3 of the present embodiment, a color chip 81 is arranged in front of the CCD 2 to constitute a color CCD 2a, and the simultaneous endoscope apparatus 1 is constructed during normal observation. ing. The color imaging signal from the color CCD 2a is converted into color image data by the A / D converter 24, color-separated by the color separation circuit 82, input to the white balance circuit 25, and sent to the memory 83 via the selector 26. , 84, and 85, the image processing circuit 30 performs interpolation processing and the like, and then performs desired image processing.
[0061]
As shown in FIG. 35, the rotary filter 86 of the light source device 4 includes an R2 filter 14r2, a G2 filter 14g2, and a B2 filter 14b2 having spectral characteristics similar to those of the second filter set of the first embodiment. The filter moving motor is rotated based on a control signal from a mode switching circuit 42 which is driven to rotate by a rotary filter motor 18 based on a control signal from a circuit 17 and receives an instruction signal from a mode switch 41 provided in the electronic endoscope 3. 87 allows insertion and removal from the optical path.
[0062]
In the present embodiment configured as described above, during normal observation, the rotary filter 86 is removed from the optical path, and white light is applied to the living tissue. Then, the biological tissue image by the white light is captured by the color CCD 2a. At this time, the spectral characteristics of the color chip 81 on the front surface of the CCD 2 are shown in FIG.
[0063]
On the other hand, at the time of narrowband light observation, the rotating filter 86 is inserted on the optical path, and the living tissue is irradiated with the field sequential light by the R2 filter 14r2, the G2 filter 14g2, and the B2 filter 14b2. Then, an image of the living tissue by this plane-sequential light is captured by the color CCD 2a.
[0064]
Therefore, when observing the narrow band light, the living tissue is irradiated with the surface normal light having discrete narrow band spectral characteristics by the R2 filter 14r2, the G2 filter 14g2, and the B2 filter 14b2. The same effect as in the embodiment can be obtained.
[0065]
37 to 46 relate to the third embodiment of the present invention, FIG. 37 is a configuration diagram showing a configuration of an endoscope device, and FIG. 38 is a diagram showing bandpass characteristics of a band limiting filter of FIG. 39 is a diagram showing the spectral characteristics of discrete narrow-band plane-sequential light by the band-limiting filter of FIG. 38, FIG. 40 is a diagram showing band-pass characteristics of a first modification of the band-limiting filter of FIG. 37, and FIG. FIG. 42 is a diagram showing spectral characteristics of discrete narrow-band plane-sequential light by the band-limiting filter of FIG. 40, FIG. 42 is a diagram showing band-pass characteristics of a second modification of the band-limiting filter of FIG. 37, and FIG. FIG. 44 is a diagram showing an example of the spectral characteristics of the xenon lamp of FIG. 37; FIG. 44 is a diagram showing the band-pass characteristics of the third modification of the band-limiting filter of FIG. 37 when the xenon lamp has the spectral characteristics of FIG. 43; Shows the configuration of a modification of the light source device of FIG. Diagram, FIG. 46 is a diagram showing a decrease in light rotating filter arrangement of Figure 45.
[0066]
Since the third embodiment is almost the same as the first embodiment, only different points will be described, and the same components will be denoted by the same reference numerals and description thereof will be omitted.
[0067]
As shown in FIG. 37, the light source device 4 of the present embodiment has a rotating filter 91 in which the R1 filter 14r1, the G1 filter 14g1, and the B1 filter 14b1 are arranged, and a band shown in FIG. A band limiting filter 92 having multi-modal band-pass characteristics (R2 band, G2 band, B2 band). The rotation filter 91 is rotationally driven by the rotation filter motor 18 based on a control signal of the control circuit 17, The limiting filter 92 is inserted and removed from the optical path by the filter moving motor 87 based on a control signal from the mode switching circuit 42 which has received an instruction signal from the mode switching switch 41.
[0068]
In the present embodiment configured as described above, the band-sequential filter 92 is inserted into the optical path, so that the plane-sequential light transmitted through the rotation filter 91 becomes a discrete narrow-band surface as shown in FIG. Since the light is sequentially emitted and the living tissue is irradiated with the narrow-band surface-sequential light, the present embodiment can provide the same effect as that of the first embodiment.
[0069]
In the present embodiment, the band limiting filter 92 is configured to have narrow band characteristics in three bands of RGB as shown in FIG. 38. However, the present invention is not limited to this. If it is desired to make it narrow, it is not necessary to narrow all the three bands, but only the B band. Therefore, as shown in FIG. A band limiting filter may be used, and by combining such a band limiting filter with the RGB rotation filter 91, it is possible to irradiate living tissue with plane-sequential light having a narrow band characteristic only in the B band as shown in FIG. .
[0070]
In order to provide only the B band with a narrow band characteristic, the band limiting filter 92 may be a band limiting filter that converts RGB light into B 'only light as shown in FIG. As a specific example of the characteristic, a long band has a bandpass characteristic of 420 nm and a half width of 20 to 40 nm.
[0071]
With the spectral characteristics as shown in FIG. 42, observation with illumination light having a narrow band characteristic including 420 nm, which is a band in which the absorption of blood in the visible light region is large, makes it possible to enhance the capillary structure on the mucosal surface. Can be reproduced with contrast.
[0072]
In addition, when the cut-off characteristic of the rotating filter 91 on the short wavelength side can be used, such as when the xenon lamp has a characteristic in which the spectral characteristic is attenuated in the short wavelength region as shown in FIG. As described above, a band-limiting filter may be used as shown in “Short wavelength side has open characteristics instead of bandpass characteristics”.
[0073]
Considering that the energy of the lamp decreases in the short wavelength region and that the spectral sensitivity characteristic of the CCD decreases in this region, as a result of performing the color adjustment processing such as white balance, the gain of the B2 band image is reduced. It is overly augmented and results in a very noisy image.
[0074]
Therefore, as a modified example of the light source device, as shown in FIG. 45, a dimming rotation filter 95 is removably inserted into the optical path so as to take white balance in consideration of spectral characteristics other than a filter such as a lamp and a CCD. After that, the light amount of each band is adjusted on the light source side so that each band image has an appropriate SN characteristic.
[0075]
That is, as shown in FIG. 46, the respective components corresponding to the B1 filter 14b1 of the rotary filter 91 are transmission portions, and the portions corresponding to the R1 filter 14r1 and the G1 filter 14g1 reduce the respective band lights, as shown in FIG. It is configured as a light-attenuating filter. The dimming rotation filter 95 is driven to rotate by a rotation filter motor 96 based on the control signal of the control circuit 17, similarly to the rotation filter 91, and is controlled by the mode switching motor 97 based on the control signal from the mode switching circuit 42. The radial direction can move perpendicular to the optical path, and the drive timing is synchronized with the rotation filter 91.
[0076]
47 to 50 relate to the fourth embodiment of the present invention, FIG. 47 is a configuration diagram showing a configuration of the endoscope device, and FIG. 48 is a diagram showing light emitted from the light source device during normal observation in FIG. FIG. 49 is a diagram showing an example of the spectral distribution, FIG. 49 is a diagram showing the illumination timing of each band by the power supply unit in FIG. 47 and the light amount control timing at that time, and FIG. It is a figure which shows an example of the spectral distribution of the light irradiated.
[0077]
Since the fourth embodiment is almost the same as the third embodiment, only different points will be described, and the same components will be denoted by the same reference numerals and description thereof will be omitted.
[0078]
In the light source device of the present embodiment, as shown in FIG. 47, the power supply unit 10 can change the drive voltage of the xenon lamp 11 by receiving a control signal from the dimming circuit 43.
[0079]
Considering the characteristics of the lamp, the spectral distribution of the light emitted from the actual light source device is as shown in FIG. In view of the fact that the energy of the lamp decreases in the short wavelength region and that the spectral sensitivity characteristics of the CCD decrease in this region, the gain of the B2 band image becomes excessive as a result of performing the color adjustment processing such as white balance. The result is an increased and very noisy image.
[0080]
Therefore, in the present embodiment, even after white balance is taken in consideration of spectral characteristics other than filters such as lamps and CCDs, the light amount of each band is adjusted on the light source side so that each band image has appropriate SN characteristics. To adjust. It is assumed that the band limiting filter 92 has the spectral characteristics shown in FIG.
[0081]
FIG. 49 shows the illumination timing of each band and the light amount control timing at that time. At the time of normal observation in which the band limiting filter 92 is not inserted on the optical path, the power supply unit 10 receives the control signal from the dimming circuit 43 and drives the xenon lamp 11 for the illumination timing shown in FIG. To control the light amount as shown in FIG. 49 (b). The reason why the light amount is reduced during the light blocking period is to reduce the heat generated from the lamp.
[0082]
On the other hand, at the time of narrow-band light observation in which the band-limiting filter 92 is inserted on the optical path, the power supply unit 10 receives a control signal from the dimming circuit 43 and receives a xenon lamp at the illumination timing shown in FIG. The light level control as shown in FIG. 49D is performed by controlling the voltage level of the drive voltage 11.
[0083]
As described above, in this embodiment, in addition to the effects of the third embodiment, the spectral distribution of the light emitted from the light source when the voltage level of the driving voltage of the xenon lamp 11 is not controlled (see FIG. 48) Spectral characteristics as shown in FIG. 50 are obtained, and light amount control in which each band image has appropriate SN characteristics can be realized.
[0084]
FIG. 51 is a configuration diagram showing a configuration of an endoscope apparatus according to a fifth embodiment of the present invention.
[0085]
Since the fifth embodiment is almost the same as the third embodiment, only different points will be described, and the same components will be denoted by the same reference numerals and description thereof will be omitted.
[0086]
As shown in FIG. 51, in the electronic endoscope 3 according to the present embodiment, a color chip 101 is arranged on the front surface of the CCD 2 to constitute a color CCD 2a, and the simultaneous endoscope apparatus 1 is constituted. The color imaging signal from the color CCD 2a is converted into color image data by the A / D converter 24, color-separated by the color separation circuit 102, input to the white balance circuit 25, and sent to the memory 103 via the selector 26. After that, the image processing circuit 30 performs an interpolation process or the like, and then performs a desired image process.
[0087]
The light source device 4 includes a band-limiting filter 92 having multi-modal band-pass characteristics (see FIGS. 38, 40, and 44). The filter is inserted into and removed from the optical path by a filter moving motor 87 based on a control signal from the circuit 42.
[0088]
In the present embodiment configured as described above, by inserting the band limiting filter 92 in the optical path, the spectral characteristics of the image captured by the CCD 2 via the color chip 101 are discrete narrow band images (FIG. 39), the image processing of this narrow band image can provide the same effects as in the third embodiment in this embodiment.
[0089]
FIG. 52 is a configuration diagram showing a configuration of an endoscope apparatus according to the sixth embodiment of the present invention.
[0090]
Since the sixth embodiment is almost the same as the fifth embodiment, only different points will be described, and the same components will be denoted by the same reference numerals and description thereof will be omitted.
[0091]
In this embodiment, as shown in FIG. 52, a light source device 112 for narrowband observation is provided separately from a light source device 111 for normal observation.
[0092]
The light source device 111 has a xenon lamp 11 as illumination light emitting means, and white light from the xenon lamp 11 is incident on an incident surface of a light guide 15 of an electronic endoscope 3 having a color CCD 2 a via a diaphragm device 13. It is supposed to be.
[0093]
The light source device 112 includes an extra-high pressure mercury lamp 113 as illumination light emitting means. Light from the extra-high pressure mercury lamp 113 is dimmed by the diaphragm device 13, and is transmitted to the electronic endoscope 3 via the band-limiting filter 92. The light is incident on an incident surface of an illumination probe 114 inserted through a treatment instrument channel (not shown).
[0094]
Here, the aperture devices 13 of the light source devices 111 and 112 are controlled by the dimming circuit 43 based on the control signal from the mode switching circuit 42 and the dimming control parameters from the dimming control parameter switching circuit 44. Has become.
[0095]
In the present embodiment, during normal observation, the aperture device 13 of the light source device 111 is set to be bright, and the aperture device 13 of the light source device 112 is set to be dark or shut off.
[0096]
During narrow-band light observation, the aperture device 13 of the light source device 112 is set to be bright, and the aperture device 13 of the light source device 111 is set to be dark or blocked.
[0097]
By setting each of the aperture devices 13 in this manner, the narrow band light is emitted from the exit surface of the illumination probe 114 during narrow band light observation, so that the present embodiment also has the same effect as the fifth embodiment. Can be obtained.
[0098]
53 to 57 relate to the seventh embodiment of the present invention, FIG. 53 is a configuration diagram showing a configuration of an endoscope apparatus, and FIG. 54 is a diagram showing an example of a spectral distribution of the xenon lamp of FIG. 55 is a diagram showing an example of the spectral distribution of the ultra-high pressure mercury lamp of FIG. 53, FIG. 56 is a configuration diagram showing the configuration of the light mixing unit of FIG. 53, and FIG. 57 is a light source for narrow band observation by the light mixing unit of FIG. FIG. 3 is a diagram illustrating an example of a spectral distribution of light emitted from the device.
[0099]
Since the seventh embodiment is almost the same as the third embodiment, only different points will be described, and the same components will be denoted by the same reference numerals and description thereof will be omitted.
[0100]
In the light source device 3 of the present embodiment, as shown in FIG. 53, two lamps, a xenon lamp 11 having a relatively broad spectral distribution as shown in FIG. 54, and an optical path orthogonal to the optical path of the xenon lamp 11 55, and a light mixing section 121 for mixing respective lights from the xenon lamp 11 and the ultra-high pressure mercury lamp 113 with a plurality of emission line spectra as shown in FIG. It is composed. Then, the light mixed by the light mixing unit 121 is supplied to the electronic endoscope 3 via the diaphragm device 13 and the rotary filter 91.
[0101]
As shown in FIG. 56, the light mixing unit 121 includes an aperture 122 for adjusting the amount of light from the xenon lamp 11, an aperture 123 for adjusting the amount of light from the ultra-high pressure mercury lamp 113, and an aperture 122 and an aperture 123. A half mirror 124 that combines the obtained lights and outputs the combined light on the optical path of the diaphragm device 13 and the rotation filter 91, and a diaphragm control circuit 125 that controls the diaphragm 122 and the diaphragm 123 based on a control signal from the mode switching circuit 42. .
[0102]
At the time of narrow-band observation, the aperture control circuit 125 closes the aperture 122 on the front of the xenon lamp 11 and opens the aperture 123 on the front of the ultra-high pressure mercury lamp 113, so that the illumination light emitted from the light mixing unit 121 is The light has the same spectral characteristics as the lamp 113. Then, by transmitting this light through the rotary filter 91 of R1G1B1, the living tissue is irradiated with RGB narrow band surface sequential light as shown in FIG.
[0103]
On the other hand, at the time of normal observation, the aperture control circuit 125 closes the aperture 122 on the front of the ultra-high pressure mercury lamp 113 and opens the aperture 123 on the front of the xenon lamp 11 to emit RGB plane-sequential light enabling natural color reproduction. Irradiate living tissue.
[0104]
As described above, also in the present embodiment, the same effect as in the third embodiment can be obtained.
[0105]
In order to obtain intermediate illumination light between the xenon lamp 11 and the ultra-high pressure mercury lamp 113, the characteristics of both lamps are mixed at a ratio corresponding to the opening ratio of the stops by adjusting the opening ratio of the stops in front of both lamps. Thus, illumination light having spectral characteristics different from those of both lamps can be obtained.
[0106]
Further, in response to the mode switching, the dimming control parameter changes the dimming table, for example, to change the operation of the dimming circuit 43 to compensate for the change in the illumination light amount due to the change in the illumination light spectral distribution. . As a result, even when switching to the illumination light spectral distribution according to the purpose, such as observing the mucosal surface structure in detail, it is possible to always observe an image with appropriate brightness.
[0107]
FIG. 58 is a configuration diagram showing a configuration of an endoscope apparatus according to the eighth embodiment of the present invention.
[0108]
Since the eighth embodiment is almost the same as the first embodiment, only different points will be described, and the same components will be denoted by the same reference numerals and description thereof will be omitted.
[0109]
In the present embodiment, as shown in FIG. 58, a dedicated narrow-band light source device 131 that supplies narrow-band surface-sequential light to the electronic endoscope 3, and a narrow-band surface-sequential image captured by the electronic endoscope 3. The narrow-band observation endoscope apparatus includes a dedicated narrow-band video processor 132 for processing light.
[0110]
The narrow-band rotation filter 133 provided in the light source device 131 includes an R2 filter 14r2, a G2 filter 14g2, and a B2 filter 14b2 (see FIG. 4) to generate narrow-band RGB plane-sequential light.
[0111]
Thus, also in the present embodiment, narrow-band observation using narrow-band surface sequential light is possible.
[0112]
When the narrow-band light source device 131 having the narrow-band rotation filter 133 is connected to the narrow-band video processor 132, the control circuit 17 of the narrow-band light source device 131 sends the illumination light spectral characteristic of the narrow-band light source device 131. Is output to the dimming control parameter switching circuit 44 as an identification signal. The correspondence between the identification signal and the control parameter is recorded in advance in the dimming control parameter switching circuit 44 in the form of a correspondence table, and an appropriate control signal is output to the dimming circuit 43 based on the correspondence table. In addition, dimming control according to the illumination light spectral characteristics can be performed.
[0113]
59 and 60 relate to the ninth embodiment of the present invention, FIG. 59 is a configuration diagram showing a configuration of an endoscope apparatus, and FIG. 60 is a band limitation that can be attached to the tip of the electronic endoscope of FIG. It is a figure showing an adapter which has a filter.
[0114]
Since the ninth embodiment is almost the same as the first embodiment, only different points will be described, and the same components will be denoted by the same reference numerals and description thereof will be omitted.
[0115]
In the present embodiment, as shown in FIG. 59, an electronic endoscope 151 for normal observation, a light source device 152 for supplying field sequential light for normal observation to the electronic endoscope 151, and an electronic endoscope 151 are provided. An endoscope device 154 including a video processor 153 that performs signal processing on an image pickup signal, and an endoscope device 155 for narrowband light observation that is provided separately from the endoscope device 154. Here, the light source device 152 includes the xenon lamp 11, the aperture device 13, and the rotary filter 91 in which the R1 filter 14r1, the G1 filter 14g1, and the B1 filter 14b1 are arranged.
[0116]
The narrow-band light observation endoscope device 155 includes a small-diameter electronic endoscope 156 inserted into the treatment instrument channel of the electronic endoscope 151, and a light source that supplies narrow-band surface sequential light to the small-diameter electronic endoscope 156. A video processor 158 that performs signal processing on an image signal from the device 157 and the small-diameter electronic endoscope 156. The light source device 152 includes the ultra-high pressure mercury lamp 113 and the diaphragm device 13, and a rotary filter 160 in which the R2 filter 14r2, the G2 filter 14g2, and the B2 filter 14b2 are arranged.
[0117]
The normal observation is performed using the endoscope apparatus 154, and the narrow-band light observation is performed using the narrow-band light observation endoscope apparatus 155.
[0118]
In this embodiment, the same effect as in the first embodiment can be obtained.
[0119]
It should be noted that the endoscope device 155 for narrowband light observation can be connected to a normal endoscope.
[0120]
Further, an adapter 171 having a band limiting filter 170 as shown in FIG. 58 may be attached to the tip of the electronic endoscope 151. Accordingly, even when the endoscope device 154 is used, narrow-band light observation can be performed.
[0121]
Although FIG. 60 shows an example in which the adapter 171 having the band limiting filter 170 attached to the front surface of the objective optical system 21 is attached, the band limiting filter 170 may be attached to the front surface of the illumination lens 172.
[0122]
【The invention's effect】
As described above, according to the present invention, there is an effect that tissue information at a desired deep portion near the tissue surface of a living tissue can be obtained.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing a configuration of an endoscope apparatus according to a first embodiment of the present invention.
FIG. 2 is a configuration diagram showing a configuration of a rotary filter of FIG. 1;
FIG. 3 is a diagram illustrating spectral characteristics of a first filter set of the rotary filter of FIG. 2;
FIG. 4 is a diagram illustrating spectral characteristics of a second filter set of the rotary filter of FIG. 2;
FIG. 5 is a diagram showing a layered structure of a living tissue observed by the endoscope apparatus of FIG. 1;
FIG. 6 is a view for explaining how illumination light from the endoscope apparatus shown in FIG. 1 arrives in a layer direction of a living tissue.
FIG. 7 is a view showing each band image by plane-sequential light transmitted through the first filter set of FIG. 3;
FIG. 8 is a diagram showing each band image by plane-sequential light transmitted through the second filter set of FIG. 4;
FIG. 9 is a view for explaining dimming control by the dimming circuit of FIG. 1;
FIG. 10 is a diagram showing spectral characteristics of a first modification of the second filter set of the rotary filter in FIG. 2;
11 is a diagram illustrating spectral characteristics of a second modification of the second filter set of the rotary filter in FIG. 2;
FIG. 12 is a diagram illustrating spectral characteristics of a third modification of the second filter set of the rotary filter in FIG. 2;
FIG. 13 is a diagram showing spectral characteristics of a fourth modification of the second filter set of the rotary filter of FIG. 2;
FIG. 14 is a diagram showing a first example of a spectral distribution of the xenon lamp of FIG.
FIG. 15 is a diagram showing the spectral characteristics of a fourth modification of the second filter set of the rotary filter in the case of the spectral distribution of the xenon lamp in FIG. 14;
FIG. 16 is a diagram illustrating spectral characteristics of living tissue illumination light according to a fourth modification of the second filter set in FIG. 14;
FIG. 17 is a diagram showing a second example of the spectral distribution of the xenon lamp of FIG.
18 is a diagram showing an example of the spectral sensitivity characteristics of the CCD shown in FIG.
FIG. 19 is a diagram illustrating a second example in which the spectral distribution of the xenon lamp is the second example and the spectral sensitivity characteristic of the CCD is that of FIG. 18; Figure showing
FIG. 20 is a diagram showing spectral characteristics of a fifth modification of the second filter set in which the neutral density filter of FIG. 19 is deposited.
FIG. 21 is a configuration diagram showing a configuration of a first modification of the light source device of FIG. 1;
FIG. 22 is a configuration diagram showing a configuration of a dimming rotation filter of FIG. 21;
FIG. 23 is a configuration diagram showing a configuration of a second modification of the light source device of FIG. 1;
FIG. 24 is a diagram showing the dimming characteristics of a first dimming filter constituting the dimming filter of FIG. 23;
FIG. 25 is a diagram showing the dimming characteristics of a second dimming filter constituting the dimming filter of FIG. 23;
FIG. 26 is a diagram showing the dimming characteristics of the dimming filter of FIG. 23;
FIG. 27 is a view showing an example showing detailed spectral characteristics of a second filter set of the rotary filter of FIG. 2;
FIG. 28 is a diagram illustrating spectral characteristics of a sixth modification of the second filter set of the rotary filter in FIG. 2;
FIG. 29 is a diagram showing a configuration of a main part of a modification of the video processor of FIG. 1;
FIG. 30 is a first diagram illustrating the operation of the video processor in FIG. 29;
FIG. 31 is a second diagram illustrating the operation of the video processor in FIG. 29;
FIG. 32 is a diagram showing a seventh modification of the second filter set of the rotary filter of FIG. 2;
FIG. 33 is a view showing the spectral characteristics of a seventh modification of the second filter set shown in FIG. 32;
FIG. 34 is a configuration diagram showing a configuration of an endoscope apparatus according to a second embodiment of the present invention.
FIG. 35 is a configuration diagram showing the configuration of the rotary filter of FIG. 34;
FIG. 36 is a view showing the spectral characteristics of the color chip of FIG. 34;
FIG. 37 is a configuration diagram showing a configuration of an endoscope apparatus according to a third embodiment of the present invention.
FIG. 38 is a diagram showing band-pass characteristics of the band-limiting filter shown in FIG. 37;
39 is a diagram showing the spectral characteristics of discrete narrow-band plane-sequential light by the band-limiting filter of FIG. 38;
FIG. 40 is a diagram showing bandpass characteristics of a first modification of the band-limiting filter shown in FIG. 37;
FIG. 41 is a diagram showing the spectral characteristics of discrete narrow-band plane-sequential light by the band-limiting filter of FIG. 40;
FIG. 42 is a diagram showing bandpass characteristics of a second modification of the bandpass filter of FIG. 37;
FIG. 43 shows an example of the spectral characteristics of the xenon lamp in FIG. 37.
FIG. 44 is a diagram showing band-pass characteristics of a third modification of the band-limiting filter shown in FIG. 37 when the xenon lamp has spectral characteristics shown in FIG. 43;
FIG. 45 is a configuration diagram showing a configuration of a modification of the light source device of FIG. 37;
FIG. 46 is a diagram showing a configuration of a dimming rotation filter of FIG. 45;
FIG. 47 is a configuration diagram showing a configuration of an endoscope apparatus according to a fourth embodiment of the present invention.
48 is a diagram showing an example of the spectral distribution of light emitted from the light source device during normal observation in FIG. 47.
49 is a diagram showing illumination timing of each band by the power supply unit of FIG. 47 and light amount control timing at that time.
50 is a view showing an example of the spectral distribution of light emitted from the light source device during narrow-band observation by the power supply unit in FIG. 47.
FIG. 51 is a configuration diagram showing a configuration of an endoscope apparatus according to a fifth embodiment of the present invention.
FIG. 52 is a configuration diagram showing a configuration of an endoscope apparatus according to a sixth embodiment of the present invention.
FIG. 53 is a configuration diagram showing a configuration of an endoscope apparatus according to a seventh embodiment of the present invention;
54 shows an example of the spectral distribution of the xenon lamp in FIG. 53.
FIG. 55 is a view showing an example of the spectral distribution of the extra-high pressure mercury lamp of FIG. 53.
FIG. 56 is a configuration diagram showing the configuration of the light mixing unit in FIG. 53;
FIG. 57 is a diagram showing an example of a spectral distribution of light emitted from the light source device at the time of narrow band observation by the light mixing unit in FIG. 56.
FIG. 58 is a configuration diagram showing a configuration of an endoscope apparatus according to an eighth embodiment of the present invention.
FIG. 59 is a configuration diagram showing a configuration of an endoscope apparatus according to a ninth embodiment of the present invention.
60 is a diagram showing an adapter having a band limiting filter that can be attached to the tip of the electronic endoscope in FIG. 59.
[Explanation of symbols]
1. Endoscope device
2 ... CCD
3. Electronic endoscope
4: Light source device
5. Observation monitor
6. Image filing device
7 Video processor
10 Power supply section
11 ... Xenon lamp
12: Heat ray cut filter
13 ... Aperture device
14 ... Rotary filter
15 ... Light guide
16 ... Condensing lens
17 ... Control circuit
18 ... Rotary filter motor
19: Mode switching motor 19
20 ... CCD drive circuit
21 Objective optical system
22 ... Amplifier
23 Process circuit
24 ... A / D converter
25 ... White balance circuit
26 ... Selector
27, 28, 29 ... Synchronized memory
30 ... Image processing circuit
31, 32, 33 ... D / A circuit
34 ... Coding circuit
35 ... Timing generator
41… Mode switch
42 ... Mode switching circuit
43 ... Dimming circuit
44 ... Dimming control parameter switching circuit

Claims (3)

An illumination light supply unit that supplies illumination light including a visible light region; an endoscope having an imaging unit that irradiates the illumination light onto the subject and captures the subject with return light; and an imaging signal from the imaging unit. An endoscope device having signal processing means for processing.
A plurality of the illumination lights are arranged so as to be arranged on an optical path from the illumination light supply means to the imaging means, and the tissue information of the tissue in the body cavity of the subject is separated and visible at a layer level. A band limiting unit configured to limit a band of at least one wavelength region among the wavelength regions so as to narrow the band and form a band image of a discrete spectral distribution of a subject obtained from the narrow band light on the imaging unit. the endoscope apparatus according to. A mode switching unit that switches between a normal observation mode for obtaining an image for normal observation based on the illumination light and a narrow band observation mode for obtaining a band image of the discrete spectral distribution obtained by the band limiting unit. The endoscope apparatus according to claim 1, wherein: Illumination light supply means for supplying illumination light in a plurality of wavelength regions including a visible light region,
This narrow-band light is limited by narrowing the band of at least one wavelength region of the plurality of wavelength regions of the illumination light, which is disposed on the optical path of the illumination light supplied from the illumination light supply unit. A band limiting unit that forms a band image of a discrete spectral distribution of the subject obtained on the imaging unit,
The normal observation mode for obtaining an image for normal observation based on the illumination light, and the tissue information of the tissue in the body cavity of the subject is separated at a layer level from the band image of the discrete spectral distribution obtained by the band limiting unit. Control means for controlling the generation of the light having the discrete spectral distribution by the band-limiting means, based on a mode switching instruction for switching between a narrow band observation mode to be made visible and
A light source device comprising:

Images