JP3586157B2 - Subject observation device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a subject observation device such as an endoscope device suitable for observation of a subject such as a blood vessel structure of a living tissue.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, an electronic endoscope apparatus which includes a slender insertion portion to be inserted into a lumen, images a subject at the distal end of the insertion portion, displays the subject on a monitor, and observes and treats the electronic endoscope device has been widely used.
In the conventional example, the spectral sensitivity characteristics of the electronic endoscope apparatus are set in advance with emphasis on color reproduction.
[0003]
Further, Japanese Patent Application Laid-Open No. 1-217415 (Japanese Patent No. 2686089) discloses a technique in which a rotary filter is replaced in a field sequential electronic endoscope in order to obtain images of a plurality of wavelengths.
In this conventional example, the main focus has been on observation of a near-infrared image and observation of a blood flow state such as hemoglobin.
[0004]
[Problems to be solved by the invention]
However, in the conventional endoscope apparatus or the like, a blood vessel structure or the like running in the depth direction near the surface of a living tissue in a body cavity cannot be clearly observed.
[0005]
(Object of invention)
The present invention has been made in view of the above points, and has as its object to provide a subject observation apparatus capable of clearly observing a blood vessel structure or the like running in the depth direction near the surface of a subject such as a living body. And
[0006]
[Means for Solving the Problems]
First illumination light generating means for generating illumination light of a first wavelength band having a narrow half-value width capable of transmitting by a first transmission distance from the subject surface layer portion in the visible light wavelength band,
A second illumination for generating second illumination light having a narrow half-value width that can be transmitted by a second transmission distance from the surface layer of the subject within the visible light wavelength band without overlapping with the first wavelength band. Light generation means;
Imaging means capable of imaging a subject image illuminated with the first illumination light and the second illumination light;
Display means for displaying an object information image representing object information at the first transmission distance and the second transmission distance of the object image based on an output signal of the imaging means;
By imaging the subject illuminated with the illumination light of the first and second wavelength bands each having a narrow half-value width by the imaging unit, the subject can be used for vascular running in a portion having a different transmission distance. Images can be obtained, and these are combined with different color signals or the like and displayed on the display means as an object information image so that portions having different transmission distances can be clearly observed.
[0007]
R illumination light generating means for generating illumination light in the R wavelength band of the visible light wavelength band;
G illumination light generating means for generating illumination light of a G wavelength band among the visible light wavelength bands,
B illumination light generating means for generating illumination light in the B wavelength band among the visible light wavelength bands,
A first wavelength band having a half width smaller than the half width of each of the R, G, and B wavelength bands of the visible light wavelength band and capable of transmitting a first transmission distance from the surface of the subject. First illumination light generating means for generating illumination light of
The visible light wavelength band has a half-width narrower than the half-width of each of the R, G, and B wavelength bands, and does not overlap with the first wavelength band. Second illumination light generating means for generating illumination light of a second wavelength band that can be transmitted by a transmission distance,
The visible light wavelength band has a half width smaller than the half width of each of the R, G, and B wavelength bands, and does not overlap with the first and second wavelength bands. Third illumination light generating means for generating illumination light of a third wavelength band that can be transmitted by a third transmission distance,
A first visible subject image illuminated with the illumination light in the R, G, B wavelength bands and a second visible subject image illuminated with the illumination light in the first, second, and third wavelength bands Imaging means capable of imaging
Video signal processing means for generating the first visible subject image and the second visible subject image based on an output signal of the imaging means;
Display means for displaying the first visible subject image and the second visible subject image based on an output signal of the video signal processing means;
Is provided, the first visible object image when illuminated with the illumination light in the R, G, and B wavelength bands can be obtained, and the first, second, and half widths at the half width are narrow. A second subject image illuminated with the illumination light of the third wavelength band can be obtained. Since this subject image is a subject image of a blood vessel running state of a portion having a different transmission distance, the Are displayed on the display means by combining them with different color signals or the like, so that portions having different transmission distances can be clearly observed.
[0008]
R illumination light generating means for generating illumination light in the R wavelength band of the visible light wavelength band;
G illumination light generating means for generating illumination light of a G wavelength band among the visible light wavelength bands,
B illumination light generating means for generating illumination light in the B wavelength band among the visible light wavelength bands,
Among the visible light wavelength bands, a first wavelength band having a half width smaller than the half width of each of the R, G, and B wavelength bands and capable of transmitting a first transmission distance from the surface layer of the subject. First illumination light generating means for generating illumination light;
The visible light wavelength band has a half-width narrower than the half-width of each of the R, G, and B wavelength bands, and does not overlap with the first wavelength band. Second illumination light generating means for generating illumination light of a second wavelength band that can be transmitted by a transmission distance,
The visible light wavelength band has a half width smaller than the half width of each of the R, G, and B wavelength bands, and does not overlap with the first and second wavelength bands. Third illumination light generating means for generating illumination light of a third wavelength band that can be transmitted by a third transmission distance,
A first visible subject image illuminated with the illumination light in the R, G, B wavelength bands and a second visible subject image illuminated with the illumination light in the first, second, and third wavelength bands Imaging means capable of imaging
Video signal processing means for generating the first visible subject image and the second visible subject image based on an output signal of the imaging means;
Display means for switching and displaying the first visible subject image and the second visible subject image generated by the video signal processing means based on an output signal level of the imaging means;
To display the first visible subject image when illuminated with the illumination light in the R, G, and B wavelength bands, and the first, second, and third wavelength bands having a narrow half-value width. The second subject image can be switched and displayed with respect to the state of blood vessel running in a portion having a different transmission distance by being illuminated with the illumination light.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
1 to 7 relate to a first embodiment of the present invention. FIG. 1 shows the entire configuration of an electronic endoscope apparatus according to a first embodiment of the subject observation apparatus of the present invention, and FIG. 1 shows the detailed configuration of FIG. 1, FIG. 3 shows the configuration of two filter sets provided in the rotary filter, FIG. 4 shows the spectral characteristics of each filter constituting the two filter sets of FIG. 3, and FIG. 6 shows a schematic explanatory view of the operation of the present embodiment, and FIG. 7 shows a schematic display example of a monitor screen when a living body is observed.
[0010]
A first object of the present embodiment is to provide an electronic endoscope apparatus capable of clearly observing a blood vessel structure running in the depth direction from the vicinity of the surface of a living body, Still another object is that, in the field sequential type electronic endoscope apparatus, when the spectral transmittance characteristic of the rotating filter is switched, the change of the image processing content is changed according to the switching to switch the rotating filter. It is an object of the present invention to provide an electronic endoscope apparatus which can obtain an endoscope image which can be easily observed in each observation mode.
[0011]
As shown in FIG. 1, an electronic endoscope apparatus 1A according to a first embodiment, which forms an object observation apparatus according to the present invention, includes an electronic endoscope 2 provided with imaging means, and illumination of the electronic endoscope 2. An observation device 5 including a light source unit 3 as an observation illumination light supply unit that supplies illumination light to the light transmission unit and a signal processing unit 4A that performs signal processing on the imaging unit, and an image signal output from the observation device 5 And an observation monitor 6 that displays
[0012]
The electronic endoscope 2 includes an elongated insertion section 8 inserted into a living body (subject) 7, an operation section 9 formed at a rear end of the insertion section 8, and a universal extending from the operation section 9. A connector 11 provided at an end of the universal cable 10 can be detachably connected to the observation device 5.
[0013]
The insertion portion 8 includes a distal end portion 12, a bendable bending portion 13 provided at a rear end of the distal end portion 12, and a flexible portion (flexible portion) 14 extending from the rear end of the bending portion 13 to the front end of the operation portion 9. The bending section 13 can be bent by operating the bending knob 15 provided on the operation section 9.
[0014]
A light guide 16 is inserted into the insertion section 8 (as shown in the enlarged view), and the connector 11 is connected to the observation device 5 so that the illumination light from the light source section 3 is incident on the incident end face as shown in FIG. Supplied to
[0015]
The light is transmitted by the light guide 16 and emitted forward from the distal end surface fixed to the illumination window of the distal end portion 12 to illuminate a target site in the living body 7. The illuminated target portion is, for example, a charge-coupled device (abbreviated as CCD) 18 as a solid-state imaging device arranged at an image forming position by an objective lens 17 attached to an observation window provided adjacent to an illumination window at the distal end portion 12. And is photoelectrically converted. The objective lens 17 and the CCD 18 form an imaging unit 19 as imaging means.
[0016]
The image signal photoelectrically converted by the CCD 18 is subjected to signal processing by a signal processing unit 4A in the observation device 5 to generate a standard video signal (image signal). The video signal is output to the observation monitor 6. .
[0017]
A treatment tool insertion port 20 is provided near the front end of the operation unit 9, and the treatment tool insertion port 20 communicates with an internal channel 21 so that a treatment tool such as a biopsy forceps can be inserted through the treatment tool insertion port 20. A biopsy procedure or the like can be performed by inserting and projecting from the tip through the channel 21.
[0018]
FIG. 2 shows the configuration of the light source unit 3 and the signal processing unit 4A as the observation illumination light supply unit in the observation device 5.
The light source unit 3 includes an observation illumination light source 24 that generates observation illumination light that emits broadband light ranging from ultraviolet light to infrared light. As the light source 24, a general xenon lamp, a strobe lamp, or the like can be used. The xenon lamp and the strobe lamp emit not only visible light but also a large amount of ultraviolet light and infrared light.
[0019]
The observation illumination light source 24 is supplied with power to be turned on by a power supply 25. In front of the light source 24, a rotary filter 27 as shown in FIG.
As shown in FIG. 3, the rotary filter 27 has a double structure, and two sets of filters 28 and 29 are provided on an inner peripheral portion and an outer peripheral portion.
[0020]
The first filter set 28 on the inner peripheral side is composed of three filters R1, G1, and B1 for normal observation, and the second filter set 29 on the outer peripheral part is R2 for special observation or close observation. , G2, and B2, and the first filter set 28 and the second filter set 29 are manufactured with spectral transmittance characteristics according to the observation purpose.
[0021]
That is, in the first filter set 28, filters 28a, 28b, and 28c that transmit light of each wavelength region of red (R1), green (G1), and blue (B1) for normal observation are arranged along the circumferential direction. Filters 29a, 29b, and 29c that transmit light in the respective wavelength ranges of R2, G2, and B2 are arranged on the outer peripheral side.
[0022]
FIG. 4 shows the spectral transmission characteristics with respect to the wavelength of each filter of the first filter set 28 and the second filter set 29 shown in FIG. As shown in FIG. 4, the R1, G1, and B1 filters that constitute the first filter set 28 have the same characteristics as the R, G, and B filters widely used in a normal field sequential illumination light source.
[0023]
On the other hand, the R2, G2, and B2 filters constituting the second filter set 29 are different from the characteristics of the R, G, and B filters that are widely used in an ordinary plane-sequential illumination light source, and particularly have a narrow half-width Whr. , Whg, and Whb, and for example, R2, G2, and B2 belong to the wavelength ranges of R, G, and B, respectively. It is characterized in that the wavelength is set so as to be suitable for observing the blood vessel structure in the vicinity of the surface layer.
[0024]
That is, when the living body 7 is illuminated with the light having passed through each of the filters R2, G2, and B2, the transmission distance (depth reaching distance or depth) of the living body 7 in the depth direction is different from each other. Is set as follows.
[0025]
For this reason, an image captured in a state where the living body 7 is illuminated with light having passed through each filter corresponds to the transmission distance of light of that wavelength, and by displaying them in different colors, portions having different transmission distances can be displayed. An image that is displayed in different colors is obtained.
[0026]
Also, a filter for identifying the light illuminating the observation site by identifying whether the filter set arranged on the illumination optical path by the light source 24 in FIG. An identification circuit 31 is provided.
In addition, a rotary filter switching mechanism 32 is provided so that an inner peripheral filter set 28 and an outer peripheral filter set 29 can be selectively set on an illumination optical axis connecting the light source 24 and the incident end of the light guide 16. is there.
[0027]
In the case of normal observation, the light beam P1 (indicated by a solid line in FIG. 3) from the light source 24 faces the filter set 28 on the inner peripheral side, and in the case of special observation (or close-up observation), The light beam P2 (shown by a two-dot chain line in FIG. 3) moves the entire rotary filter 27 by the rotary filter switching mechanism 32 (shown in FIG. 1) so as to face the outer filter set 29 (shown in FIG. 1). The filter set to be arranged can be switched.
[0028]
The rotation filter switching mechanism 32 moves the motor 26 and the identification circuit 31 relatively to the light source 24, but may move the light source 24 side in the opposite direction.
Further, the rotation of the motor 26 is controlled by a control circuit 33 so as to be driven.
[0029]
The light that has passed through the rotary filter 27 and is separated in time series into light of each wavelength region of Ri, Gi, and Bi (i = 1 or 2) is incident on an incident end of the light guide 16, The light is guided to the emission end face on the distal end side through the light emission section, is emitted forward from the emission end face, and illuminates the observation site and the like.
[0030]
In order to identify the light illuminating the observation site, a filter identification signal F1 output from a filter identification circuit 31 provided in the light source unit 3 is passed through a control circuit 33 controlling the motor 26 to a timing generator 34. The timing generator 34 outputs a timing signal synchronized with the filter identification signal F1 to the CCD driver 35 and the like.
[0031]
The return light reflected from the subject (subject) such as an observation site by the illumination light is imaged on the CCD 18 by the objective lens 17 and photoelectrically converted by the CCD 18. A drive pulse from a CCD driver 35 in the signal processing unit 4 is applied to the CCD 18 via a signal line, and an electric signal (image signal) corresponding to the image of the subject photoelectrically converted by the drive pulse is applied. It is to be read.
[0032]
Therefore, this drive pulse accumulates electric charges in the CCD 18 during the opening period of the rotary filter 27 (the period during which the observation light is irradiated on the subject), and during the light blocking period (the period during which the observation light is not irradiated on the subject). The charge stored in the CCD 18 is read. In FIG. 3, for simplicity, the light-shielding portion is not provided. In actuality, the light-shielding portion is provided in an adjacent portion such as the R1 filter and the B1 filter, and the light beam hits the light-shielding portion. In this case, a light-blocking period is set.
[0033]
The electric charge read from the CCD 18 is input as an electric signal to a preamplifier 36 provided in the electronic endoscope 2 or the observation device 5 via a signal line. The image signal amplified by the preamplifier 36 is input to a process circuit 37, subjected to signal processing such as γ correction and white balance, and converted into a digital signal by an A / D converter 38.
[0034]
The digital image signal is supplied by the select circuit 39 to three first memories 41a, a second memory 41b, and a third memory 41 provided corresponding to, for example, each of red (R), green (G), and blue (B). 41c is selectively stored.
[0035]
The color signals of Ri, Gi, and Bi (indicated by SR, SG, and SB in FIG. 5) stored in the first memory 41a, the second memory 41b, and the third memory 41c are read out at the same time, and the image processing unit 42 The image processing unit 42 performs image processing.
[0036]
The output signal from the image processing unit 42 is converted by a D / A converter 43 into analog color signals (indicated by R, G, and B in FIG. 2 for simplicity), and input / output interfaces (I / O) ) 44 to the observation monitor 6 as R, G, B color signals, so that the observation part 6 is displayed in color.
[0037]
Further, a rotation filter switching instruction device 45 is connected to the electronic endoscope apparatus 1A, and by performing an instruction to switch the rotation filter 27, a rotation filter switching instruction signal C1 is output to the rotation filter switching mechanism 32, and the rotation filter At the same time as the switching of 27, the image processing change instruction signal C2 is output to the image processing unit 42 to instruct the image processing unit 42 to change the processing contents.
[0038]
In the signal processing unit 4A of the observation device 5, a timing generator 34 for generating the timing of the entire system is provided, and the timing generator 34 controls the control circuit 33, the CCD driver 35, the select circuit 39 and the like. Synchronized.
[0039]
FIG. 5 shows a specific configuration example of the image processing unit 42.
Color signals SR, SG, and SB generated by being imaged under illumination light of Ri, Gi, and Bi from the memories 41a, 41b, and 41c (more specifically, under illumination light of R1, G1, and B1) , And the color signals R, G, and B obtained under the illumination light of R2, G2, and B2) are supplied to R, G, and B gain adjustment units 51a, 51b, and 51c, respectively. The gain is adjusted by the gain set by the gain parameters Pa, Pb, and Pc from the gain parameter changing circuit 52 and output to the D / A converter 43 side.
[0040]
The gain parameter changing circuit 52 applies the gain parameters Pa, Pb, Pc corresponding to the image processing change instruction signal C2 from the rotation filter switching instruction device 45 to the R, G, B gain adjusters 51a, 51b, 51c.
In this case, a gain parameter storage unit 53 is provided in the image processing unit 42. When the image processing change instruction signal C2 is input, the gain parameter change circuit 52 stores the gain parameter stored in the gain parameter storage unit 53 in advance. The gain parameter read request signal C3 to be read is applied to the gain parameter storage unit 53 to output a corresponding gain parameter set C4, and the gain parameters Pa, Pb, Pc constituting the gain parameter set are set to R, G, B. The voltage may be applied to the gain adjusters 51a, 51b, 51c.
[0041]
Next, the operation of the present embodiment will be described.
When performing normal observation, observation is performed by disposing the first filter set 28 on the illumination optical path. In this case, the white light from the light source 24 passes through the first filter set 28 having the same characteristics as the normal R, G, B filters whose characteristics are shown in FIG. And the living body 7 is illuminated with the R, G, B plane-sequential illumination light.
[0042]
Then, image signals (color signals) of R, G, and B obtained by imaging the living body 7 illuminated with the R, G, and B plane-sequential illumination light by the CCD 18 are converted into digital signals, and the first memory 41a and the second memory 41b, and are sequentially stored in the third memory 41c.
[0043]
The R, G, and B color signals temporarily stored in the first memory 41a, the second memory 41b, and the third memory 41c are read out at the same time, input to the image processing unit 42, and output by the image processing unit 42. Processing is performed.
Then, the image is converted into an analog color signal by the D / A converter 43, and an image of the living body 7 is displayed in color on the monitor 6 for observation.
As described above, in the case of normal observation, the first filter set 28 is used so as to cover the entire visible range so as to obtain natural color reproduction.
[0044]
On the other hand, in a case where the top priority is to obtain the surface unevenness structure and the blood vessel construction image of the living mucous membrane in the proximity of the living body 7 (in the close observation mode), observation is performed using the second filter set 29. Have to be able to.
[0045]
In this case, the user operates, for example, a proximity observation mode switch that constitutes the rotary filter switching instruction device 45, and when the switch is turned on, the rotary filter switching instruction signal C1 is output to the rotary filter switching mechanism 32. When the rotation filter 27 is switched, an image processing change instruction signal C2 is output to the image processing unit 42 to instruct the image processing unit 42 to change the processing contents.
[0046]
That is, when the rotation filter switching instruction signal C1 is input, the rotation filter switching mechanism 32 moves the rotation filter 27 and the like upward in FIG. 1 (to the left in FIG. 3), and the light beam P2 of the light source 24 is shifted to the second position. The movement is set so as to hit the side of the second filter set 29, and when this state is set, it is detected by the filter identification circuit 31 and the rotation filter switching operation ends.
[0047]
In this close-up observation mode, as shown in FIG. 4, the light transmission characteristics of the filters R2, G2 and B2 are half widths Whr, Whg and Whb narrower than those of the filters R1, G1 and B1. , The image processing change instruction signal C2 is output to the image processing unit 42 in conjunction with the switching to the second filter set 29, and the R, G, and B gain adjustments are performed. The gains of the sections 51a, 51b, and 51c are made larger than in the normal observation mode so that an image suitable for observation is obtained.
[0048]
In the case of the close-up observation mode in the present embodiment, an image (component image) obtained under illumination by each of the filters R2, G2, and B2 is used instead of obtaining an image in a state of white balance. Since the main purpose is to display the image so that it can be easily recognized, for example, the gain value is set so that the luminance levels of the obtained component images are almost the same, or the images are displayed in different colors. The gain value is set so as to have a luminance level that is easy to identify (in consideration of the human recognition function for colors) when displayed with.
[0049]
When the observation is performed in the close-up observation mode in this manner, the observation is suitable for observing the cross-sectional structure of the living mucous membrane as shown in FIG.
A cross section of a living mucosa, such as a gastric mucosa, in which blood vessels are abundantly formed in the depth direction is generally as shown in FIG. Due to the uneven structure on the surface, there are capillaries near the surface layer, blood vessels that are slightly deeper than the capillaries, and a deeper deep blood vessel network.
As a point for observing the living mucous membrane, it is desirable to obtain an observation image that can show such a state of the blood vessel construction. Then, by observing the state of vascular construction, early detection of a lesion such as cancer becomes easy.
[0050]
The manner in which the light observing the living body 7 in which the blood vessels are traveling in the depth direction and reaching the inside of the living body 7 will be described. As shown in FIG. 6B, for example, the shorter the wavelength of visible light (blue light), the lower the depth of penetration into the living body. The longer the wavelength (from green to red), the deeper the living body 7 reaches. In other words, when observed with short-wavelength light, information up to a relatively shallow portion of the mucous membrane is reflected in the (imaged) image. Conversely, with short-wavelength light, up to the deep layer where many thick blood vessels exist, short-wavelength light Does not penetrate deep, so the thick blood vessels are not reflected in the image. Therefore, in order to observe the deep side, it is necessary to observe with light of a long wavelength having a deeper depth.
[0051]
Each filter of R1, G1, and B1 of the first filter set 28 for normal observation realizes a natural color reproduction. Therefore, as shown in FIG. Also has wide characteristics. In the case of this characteristic, light of a wide wavelength range is mixed with light of B1 which is short-wavelength light, and from light with a small depth to light with a medium depth in FIG. Observe at the same time. As a result, the B image reflects the mixture of the capillaries near the surface layer and the blood vessels near the midway, and these are mixed as the same signal.
[0052]
On the other hand, in the light of B2 of the second filter set 29 having the narrow half-value width Whb, the width of the wavelength included in the light of B2 is limited to be narrow. Since the ratio of light with a small depth of penetration to the light increases, the image observed with the light of B2 improves the structure on the surface and the contrast of the capillary network. It will be easier.
[0053]
It is clear from the comparison of the graphs of the spectral characteristics of the R1, G1, and B1 filters of the first filter set 28 and the R2, G2, and B2 filters of the second filter set 29 in FIG. 4 that the narrow half-width of each filter in the close observation mode is obtained. The center wavelength is adjusted by Whr, Whg, and Whb, and the bands are set so as to be separated from each other without overlapping.
[0054]
Further, the bandwidth or half-value width Whg of G2 is narrower than G1 and is separated from the band of B2 on the wavelength axis, so that the half-value width Whg of the wavelength included in G2 is limited to be narrow, as in the case of B2 described above. The difference from the image based on B2 becomes clearer, and the image based on G2 does not reflect the surface structure and the capillaries, but instead reflects the blood vessel construction image near the middle layer more prominently.
[0055]
Also, the bandwidth or half-width Whr of R2 is made narrower than R1 and separated from G2 on the wavelength axis in the same manner, and only the deep thick blood vessels are reflected in the image by R2.
As described above, the image obtained by imaging using each band of R2, G2, and B2 is subjected to signal processing in substantially the same manner as in the normal observation mode except that the gain adjustment in the image processing unit 42 is different. , RGB color signals are displayed on the observation monitor 6 in color.
[0056]
In this case, the information in the depth direction of the blood vessel construction becomes a color difference, and these are combined and displayed in color. Unlike the normal observation mode, the information is reproduced more remarkably.
That is, the capillary network near the surface layer is reproduced yellow (because only B is absorbed and G and R are colored), the blood vessel network near the middle layer (magenta to red), and the thick blood vessels near the deep layer are reproduced more bluish.
[0057]
Therefore, on the monitor screen of the observation monitor 6, the blood vessel structure traveling at different depths is displayed in different colors as schematically shown in FIG. The state can be grasped clearly.
[0058]
As described above, in the close observation mode, unlike in the case of the broad RGB characteristics, by separating each band on the wavelength axis with a narrower half width, the running state in the depth direction of the blood vessel is more remarkable. Image can be obtained.
[0059]
As described above, according to the present embodiment, it is possible to obtain an endoscope image suitable for normal observation, and also obtain an endoscope image in which the state of the blood vessel construction in the depth direction can be known by switching the filter set. Can be.
[0060]
As a first modification of the second filter set 29, for example, a filter set having characteristics as shown in FIG. 8 may be used. In the first modified example, for example, the filter G2 in the second filter set 29 in FIG. 4 is used as a filter R2, and further, filters G2 and B2 having narrow half-value widths on the shorter wavelength side than the filter R2 are provided.
[0061]
The filter G2 is slightly longer than the filter G2 in FIG. 4, and the filter B2 is set slightly shorter than the filter B2 in FIG.
When the second filter set 29 of the first modified example is employed, a thick blood vessel structure near the deep layer cannot be observed, but a more detailed observation of the blood vessel structure from the surface unevenness structure to the blood vessel structure near the middle layer with different colors is performed. Suitable for.
[0062]
As a second modification of the second filter set 29, for example, a filter set having characteristics as shown in FIG. 9 may be used. In the second modification, by setting all the filters of R2, G2, and B2 in a short wavelength range, it is possible to detect scattering and absorption changes near the surface layer of the living mucous membrane with high sensitivity. This is suitable for observing a disease state occurring near the mucosal surface such as early cancer.
[0063]
Further, as a third modification, the second filter set 29 may be a filter set as shown in FIG. As shown in FIG. 10, by setting filters B2 and G2 centering on two wavelengths that exhibit the same absorption in the absorption characteristics of the living tissue and have different scattering characteristics, the emphasis is on the effect of scattering rather than the effect of absorption. Image reproduction can be obtained. This is suitable, for example, when imaging that the tissue structure is disordered and the degree of light scattering changes as the normal living mucosa becomes cancerous.
[0064]
(Second Embodiment)
Next, a second embodiment of the present invention will be described.
In the first embodiment, the first and second filter sets 28 and 29 have a double structure as shown in FIG. 3. However, as shown in FIG. 11, a plurality of rotary filters 27a and 27b may be used. good. In FIG. 3, each of the filter sets 28 and 29 includes three filters. However, the number of filters is not limited to three as shown in FIG. 11, and the number of filters is determined according to a desired image effect.
[0065]
When a plurality of rotary filters 27a and 27b are used as shown in FIG. 11, driving devices 55a and 55b for driving the plurality of rotary filters 27a and 27b along the illumination optical axis as shown in FIG. The driving devices 55a and 55b are connected to the rotation filter switching mechanism 32, and perform insertion / removal (insertion / retreat) movement of the rotation filters 27a and 27b to / from the illumination optical axis.
[0066]
In FIG. 12, the driving device 55a (and 55b) includes a guide rail 54j (j = a or b), a rotary filter 27j along the guide rail 54j, a motor 26j for driving the rotary filter 27j to rotate, and a filter identification circuit 31j. Are moved together to move the rotary filter 27j into and out of the illumination optical axis (FIG. 12 shows a state in which the rotary filter 27a is set to the retracted position and the rotary filter 27b is set to the inserted position).
[0067]
In the case of FIG. 12, when one of the two rotary filters 27a and 27b is installed on the optical axis, the other rotary filter is retracted from the optical axis. You may make it install in.
[0068]
Also, by preparing a filter RGB2 having a three-peak spectral transmittance characteristic as in the modification shown in FIG. 13, the filter is not rotated, and the rotary filter switching mechanism 32 inserts and retracts the light onto the optical axis. By controlling only the first and second filter sets 28 and 29 shown in FIG. 3, it is possible to obtain the same operation and effect.
[0069]
(Third embodiment)
Next, a third embodiment of the present invention will be described. The main difference from the first embodiment is that the change of the rotation filter is performed not by the rotation filter switching instruction device 45 but by the rotation filter switching determination means, and the rotation filter is switched according to the situation, and the change of the image processing content is automatically changed. The purpose is to automate the rotation filter switching.
[0070]
An electronic endoscope apparatus 1B according to the third embodiment of the present invention shown in FIG. 14 includes a rotation filter switching determination device 58 in a signal processing unit 4B.
The rotation filter switching determining device 58 receives the subject determination signal H1 that determines the observation state of the subject from the image processing unit 42 'based on the CCD output signal, and determines rotation filter switching. An image processing change instruction signal C2 is sent to the image processing unit 42 '.
[0071]
FIG. 15 shows the configuration of the image processing unit 42 'in the present embodiment. This image processing unit 42 'has a configuration in which a subject determination circuit 59 is provided in the image processing unit 42 of FIG.
As shown in FIG. 15, the image processing unit 42 'is provided with a subject determination circuit 59 for determining the observation state of the subject, and the subject determination circuit 59 receives the R, G, and B color signals (from the memories 41a to 41c). Here, SR, SG, and SB) are input as in the case of FIG.
[0072]
Then, by comparing the average value of the luminance levels of the color signals SR, SG, and SB with a reference level for determination, the living body is observed at an appropriate distance or in a normal observation state or close to the living body. It determines whether the subject is in the close observation state and outputs a subject determination signal H1 to the rotation filter switching determination device 58. When the average value of the luminance levels is less than the reference level, the subject determination signal H1 indicating that the subject is in the normal observation state, and when the average value is equal to or higher than the reference level, the subject determination signal H1 indicating that the subject is in the close observation state. Device 58 outputs. Other configurations are the same as those in FIG.
[0073]
The rotation filter switching determination device 58 sends a rotation filter switching instruction signal C1 to the rotation filter switching mechanism 32 and an image processing change instruction signal C2 to the image processing unit 42 'based on the determination result of the subject.
Other configurations are the same as those in FIG.
[0074]
Next, the operation of the present embodiment will be described.
When performing an endoscope inspection by inserting the insertion portion of the electronic endoscope 2 into the inside of the living body 7 and observing the living body 7 at an appropriate distance from the living body 7, the average value of the color signals in that case becomes less than the reference level. , The image processing unit 42 ′ determines the normal observation mode, and can perform observation in a state where the first filter set 28 is arranged on the illumination light path.
[0075]
Then, when the distal end is moved so that the distal end is brought close to the affected part in order to observe the affected part in more detail, the average value of the color signal becomes equal to or higher than the reference level, and the image processing unit 42 ′ enters the close-up observation mode. It is determined that the setting has been made, and the subject determination signal H1 indicating that the subject is in the close observation state is output to the rotation filter switching determination device 58, and the rotation filter switching determination device 58 sends the rotation filter switching instruction signal C1 to the rotation filter switching mechanism 32. In addition, switching is performed so that the second filter set 29 is arranged on the illumination light path, and the image processing change instruction signal C2 is sent to the image processing unit 42 'to adjust the gain to a gain suitable for observation.
When the automatic light control works, the switching can be automatically performed by moving faster than the response of the automatic light control.
[0076]
In the above description, the filter set is switched based on the brightness of the signal captured by the CCD 18, but the filter set may be switched based on the color tone of the signal captured by the CCD 18.
[0077]
For example, it may be determined from the luminance distribution of the color signal that the observer is observing the portion where the stain is sprayed, and the filter set may be changed to a filter set suitable for observing the stained image, or the gain may be adjusted. .
[0078]
FIG. 16 shows a configuration of an electronic endoscope apparatus 1C according to a modification. In FIG. 14, when the subject determination signal H1 from the image processing unit 42 'is input to the rotation filter switching determination device 58, the rotation filter switching instruction signal C1 and the like are output based on the signal H1. However, in the modification shown in FIG. 16, for example, in the electronic endoscope 2, a magnification variable lens constituting the objective lens 17 is moved to the enlargement side (telephoto side) to enlarge the image more than in the normal observation state to form an enlarged observation. A mechanism is provided.
[0079]
Then, by operating a magnifying movement lever provided on the operation unit 9 or the like of the electronic endoscope 2 or the like, or when electrically driving, a magnifying observation rate change instructing means 60 such as a magnifying switch, the magnifying observation mechanism is enlarged. A magnification change instruction signal or the like is output to move the zoom lens to change the magnification (from normal observation), and at the same time, the magnification observation instruction change means 60 sends the magnification instruction signal E1 to the rotation filter switching determination device 58. By outputting the rotation filter switching determination device 58, the rotation filter switching instruction signal C1 is output to the rotation filter switching mechanism 32 to change the normal observation filter set to the close observation filter set, and to change the image processing change instruction signal. C2 is sent to the image processing unit 42 to make it suitable for a filter set whose gain has been changed.
[0080]
For this reason, in FIG. 16, the signal processing unit 4 </ b> C has the rotation filter switching determination device 58 provided therein similarly to the case of FIG. 14, but has a configuration employing the same image processing unit 42 as in FIG. 2. . Other configurations are the same as those of the above-described embodiment.
[0081]
Also in the case of the present modification, it is possible to select and set a filter set suitable for the observation state according to the observation state, and to perform observation with a gain setting or the like suitable for image observation in that case.
[0082]
As another modified example, semi-automatic control may be performed. For example, as in the case of FIG. 2, the change from the first filter set 28 for normal observation to the second filter set 29 is manually performed by the rotary filter switching instruction device 45, but the change from the second filter set 29 to the first filter set 29 is performed. The change to the set 28 may be automatically performed by the rotation filter switching determination device 58 (as determined by the image processing unit 42 ') as in the case of FIG.
[0083]
Alternatively, the rotation filter switching determination device 58 and the rotation filter switching instructing device 45 may be used to select and set automatic or manual.
According to the present embodiment, since the operation of changing the characteristics can be automated, the trouble of the user can be simplified.
[0084]
(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described with reference to FIG. The present embodiment achieves the purpose of simplifying the white balance setting operation by realizing the operation for preparing the white balance setting value for each filter set in advance by one operation.
[0085]
The electronic endoscope apparatus 1D according to the fourth embodiment shown in FIG. 17 includes a signal processing unit 4D in which a rotary filter switching device 63 is provided in a signal processing unit 4A in FIG. When the gain setting instruction signal Ge1 is input from the gain setting instruction device 64, the image processing unit 42 can be instructed to calculate a gain value for each filter of the first filter set 28 and to store the calculated value. Like that.
[0086]
Note that, in the present embodiment, the image processing unit 42 has a gain calculating unit. In the image processing unit 42, for example, the R, G, and B gain adjustment units 51 a to 51 c shown in FIG. 5 calculate the level of each input signal and send it to the gain parameter change circuit 52. It has a function of calculating the values of the gain parameters Pa, Pb, and Pc such that the levels of the three signals obtained coincide with each other and storing the values in the gain parameter storage unit 53.
The rotary filter switching device 63 outputs a filter switching instruction signal C1 to the rotary filter switching mechanism 32.
[0087]
Next, the operation of the present embodiment will be described.
The tip of the electronic endoscope 2 is brought close to a reference object 65 such as a standard white plate, and the gain setting instruction device 64 is operated to output a gain setting instruction signal Ge1 to the rotary filter switching device 63 to instruct the start of gain setting.
[0088]
The gain setting instruction device 64 is realized by a switch or the like provided in the electronic endoscope device 1D. In response to an instruction to start gain setting from the gain setting instruction device 64, the rotation filter switching device 63 switches the setting of the rotation filter 27 to the illumination light path of the first filter set 28, and at the same time, the image processing unit 42 An appropriate gain value is calculated by a gain calculating means provided in the image processing unit 42, using gain values corresponding to the respective signals obtained when the illumination is sequentially performed by the R1, G1, and B1 filters of the first filter set 28, The data is stored in the gain parameter storage unit 53 in a form corresponding to the first filter set 28.
[0089]
When the setting and storage are performed in this manner, the gain parameters stored in the gain parameter storage unit 53 are called and used thereafter, so that an observation image in a white balance state can be obtained.
[0090]
According to the present embodiment, the gain value in the case of the filter set 28 for normal observation of the rotating filter 27 can be set and stored so as to white balance in a single instruction operation.
[0091]
In the above description, the gain setting and storage in the white filter state are described in the case of the first filter set 28, but the gain setting and storage in the white balance state are similarly performed in the case of the second filter set 29. It may be done.
[0092]
In this case, for example, when the gain setting and the storage operation in the white balance state in the case of the first filter set 28 are completed, the rotation filter switching device 63 switches to set the second filter set 29 on the optical path. Then, the gain value is set and stored so as to achieve the white balance as in the case of the first filter set 28.
[0093]
(Fifth embodiment)
Next, a fifth embodiment of the present invention will be described with reference to FIG. The present embodiment is provided with a means for notifying the user that the spectral characteristics and the image processing content have changed, and the user can recognize that the spectral sensitivity characteristics and the image processing means have changed. It was made possible.
[0094]
An electronic endoscope apparatus 1E according to the fifth embodiment shown in FIG. 18 has a signal processing section 4E in which a change content notification circuit 72 is provided in the signal processing section 4A in the electronic endoscope apparatus 1A in FIG.
[0095]
The change notification circuit 72 receives the rotation filter switching instruction signal C2 from the rotation filter switching instruction device 45 and changes information of image processing contents in the case of a filter set switched by the image processing unit 42. Are input, and the changed information is output to, for example, the input / output interface 44 to output the changed information superimposed on the video signal, and the changed information is displayed on the monitor 6 for observation. Thus, the setting state and the observation state of the apparatus 1E can be recognized.
[0096]
Further, even when the filing device 71 for recording an endoscope image is connected, since the change information is superimposed on the video signal, the setting state of the endoscopic image recorded by the device 1E can be known. I can do it.
Further, the change information from the change content notification circuit 72 can be recorded in the filing device 71 as supplementary information in the header portion of the endoscope image.
[0097]
Next, the operation of the present embodiment will be described.
The change notification circuit 72 receiving the output from the rotation filter switching instruction device 45 causes the observation monitor 6 to display the name of the current rotation filter set. Alternatively, the spectral transmittance characteristics of the rotating filter set may be displayed.
[0098]
The change notification circuit 72 that has received the current parameter setting content from the image processing unit 42 displays the content on the observation monitor 6 or a symbol representing the parameter content such as an indicator on the observation monitor 6.
[0099]
When the filing device 71 or the like is used by being connected to the electronic endoscope device 1E, the change notification result is stored not only on the observation monitor 6 but also on the header portion of the image file.
[0100]
According to the present embodiment, the user can check what system characteristics are currently on the monitor 6 and also as image file data. In particular, when the change in characteristics is delicate on the image, the user can check the current system state. By doing so, the inspection can be performed while predicting the display function on the image based on experience.
[0101]
Further, depending on the observation purpose, it is conceivable to appropriately switch the content of the image processing together with the change in the spectral characteristics. In such a case, the change can be recognized and the change in the image processing can be dealt with.
[0102]
In the above description, for example, when the second filter set is composed of four R2, G2, B2, and B3 filters as shown in FIG. 11, four memories are prepared and each is displayed in a different color. It may be displayed by means.
[0103]
In other words, when a plurality of filters having different transmission distances and narrow half-value widths are prepared, images illuminated with light passing through the filters are stored in different memories and the like, and synthesized as different color signals and the like. May be displayed on the display means.
[0104]
In the above description, for example, in the first embodiment, the means for obtaining an image in the close-up observation mode has been described in the case of plane sequential illumination and plane sequential imaging, but it is configured with simultaneous illumination and simultaneous imaging. You can also.
[0105]
For example, the living body 7 is simultaneously illuminated with light passing through the filters R2, G2, and B2. R, G, and B filters) are imaged by an electronic endoscope of a simultaneous imaging unit having a mosaic filter provided for each pixel, and the color-separated signals are stored in the first to third memories 41a in FIG. Even if the image data is stored in .about.41c, an image similar to that of the first embodiment can be obtained.
Note that embodiments and the like configured by partially combining the above-described embodiments and the like also belong to the present invention.
[0106]
[Appendix]
1. First illumination light generating means for generating illumination light of a first wavelength band having a narrow half-value width capable of transmitting by a first transmission distance from the subject surface layer portion in the visible light wavelength band,
A second illumination for generating second illumination light having a narrow half-value width that can be transmitted by a second transmission distance from the surface layer of the subject within the visible light wavelength band without overlapping with the first wavelength band. Light generation means;
Imaging means capable of imaging a subject image illuminated with the first illumination light and the second illumination light;
Display means for displaying an object information image representing object information at the first transmission distance and the second transmission distance of the object image based on an output signal of the imaging means;
An object observation device, comprising:
[0107]
2. R illumination light generating means for generating illumination light in the R (red) wavelength band of the visible light wavelength band;
G illumination light generating means for generating illumination light in a G (green) wavelength band among the visible light wavelength bands;
B illumination light generating means for generating illumination light in the B (blue) wavelength band of the visible light wavelength band;
A first wavelength band having a half width smaller than the half width of each of the R, G, and B wavelength bands of the visible light wavelength band and capable of transmitting a first transmission distance from the surface of the subject. First illumination light generating means for generating illumination light of
The visible light wavelength band has a half-width narrower than the half-width of each of the R, G, and B wavelength bands, and does not overlap with the first wavelength band. Second illumination light generating means for generating illumination light of a second wavelength band that can be transmitted by a transmission distance,
The visible light wavelength band has a half width smaller than the half width of each of the R, G, and B wavelength bands, and does not overlap with the first and second wavelength bands. Third illumination light generating means for generating illumination light of a third wavelength band that can be transmitted by a third transmission distance,
A first visible subject image illuminated with the illumination light in the R, G, B wavelength bands and a second visible subject image illuminated with the illumination light in the first, second, and third wavelength bands Imaging means capable of imaging
Video signal processing means for generating the first visible subject image and the second visible subject image based on an output signal of the imaging means;
Display means for displaying the first visible subject image and the second visible subject image based on an output signal of the video signal processing means;
An object observation device, comprising:
[0108]
3. R illumination light generating means for generating illumination light in the R wavelength band out of the visible light wavelength band,
G illumination light generating means for generating illumination light of a G wavelength band among the visible light wavelength bands,
B illumination light generating means for generating illumination light in the B wavelength band among the visible light wavelength bands,
Among the visible light wavelength bands, a first wavelength band having a half width smaller than the half width of each of the R, G, and B wavelength bands and capable of transmitting a first transmission distance from the surface layer of the subject. First illumination light generating means for generating illumination light;
The visible light wavelength band has a half-width narrower than the half-width of each of the R, G, and B wavelength bands, and does not overlap with the first wavelength band. Second illumination light generating means for generating illumination light of a second wavelength band that can be transmitted by a transmission distance,
The visible light wavelength band has a half width smaller than the half width of each of the R, G, and B wavelength bands, and does not overlap with the first and second wavelength bands. Third illumination light generating means for generating illumination light of a third wavelength band that can be transmitted by a third transmission distance,
A first visible subject image illuminated with the illumination light in the R, G, B wavelength bands and a second visible subject image illuminated with the illumination light in the first, second, and third wavelength bands Imaging means capable of imaging
Video signal processing means for generating the first visible subject image and the second visible subject image based on an output signal of the imaging means;
Display means for switching and displaying the first visible subject image and the second visible subject image generated by the video signal processing means based on an output signal level of the imaging means;
An object observation device, comprising:
[0109]
4. R illumination light generating means for generating illumination light in the R wavelength band out of the visible light wavelength band,
G illumination light generating means for generating illumination light of a G wavelength band among the visible light wavelength bands,
B illumination light generating means for generating illumination light in the B wavelength band among the visible light wavelength bands;
Among the visible light wavelength bands, a first wavelength band having a half width smaller than the half width of each of the R, G, and B wavelength bands and capable of transmitting a first transmission distance from the surface layer of the subject. First illumination light generating means for generating illumination light;
The visible light wavelength band has a half-width narrower than the half-width of each of the R, G, and B wavelength bands, and does not overlap with the first wavelength band. Second illumination light generating means for generating illumination light of a second wavelength band that can be transmitted by a transmission distance,
The visible light wavelength band has a half width smaller than the half width of each of the R, G, and B wavelength bands, and does not overlap with the first and second wavelength bands. Third illumination light generating means for generating illumination light of a third wavelength band that can be transmitted by a third transmission distance,
A first visible subject image illuminated with the illumination light in the R, G, B wavelength bands and a second visible subject image illuminated with the illumination light in the first, second, and third wavelength bands Imaging means capable of imaging
Video signal processing means for generating the first visible subject image and the second visible subject image based on an output signal of the imaging means;
Imaging magnification changing means capable of changing the imaging magnification by the imaging means;
A display unit that switches and displays the first visible subject image and the second visible subject image generated by the video signal processing unit based on an output of the imaging magnification changing unit;
An object observation device, comprising:
[0110]
【The invention's effect】
As described above, according to the present invention, out of the visible light wavelength band, the first light that generates the first wavelength band having a narrow half-width that can be transmitted by the first transmission distance from the surface layer of the subject is generated. Illumination light generating means;
A second illumination for generating second illumination light having a narrow half-value width that can be transmitted by a second transmission distance from the surface layer of the subject within the visible light wavelength band without overlapping with the first wavelength band. Light generation means;
Imaging means capable of imaging a subject image illuminated with the first illumination light and the second illumination light;
Display means for displaying an object information image representing object information at the first transmission distance and the second transmission distance of the object image based on an output signal of the imaging means;
Therefore, by imaging the subject illuminated with the illumination light of the first and second wavelength bands having a narrow half-value width by the imaging means, the subject with respect to the state of the blood vessel running and the like in the portions having different transmission distances is provided. A specimen image can be obtained, and these are combined with different color signals or the like and displayed on the display means as a subject information image, so that portions having different transmission distances can be clearly observed.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of an electronic endoscope apparatus according to a first embodiment of a subject observation device of the present invention.
FIG. 2 is a block diagram showing a detailed configuration of FIG. 1;
FIG. 3 is a diagram showing a configuration of two filter sets provided in a rotary filter.
FIG. 4 is a diagram illustrating spectral characteristics of respective filters included in the two filter sets of FIG. 3;
FIG. 5 is a block diagram illustrating a configuration of an image processing unit.
FIG. 6 is a schematic explanatory view of the operation of the present embodiment.
FIG. 7 is a diagram showing a schematic display example of a monitor screen when a living body is observed.
FIG. 8 is a diagram showing spectral characteristics and the like of filters of a second filter set in a first modified example.
FIG. 9 is a diagram showing spectral characteristics and the like of filters of a second filter set in a second modification.
FIG. 10 is a diagram showing spectral characteristics and the like of filters of a second filter set in a third modification.
FIG. 11 is a diagram illustrating a configuration of a rotary filter according to a second embodiment of the present invention.
FIG. 12 is a diagram showing a configuration near a rotary filter switching mechanism in a light source unit.
FIG. 13 is a diagram illustrating spectral characteristics and the like of a three-peak filter according to a modification.
FIG. 14 is a block diagram illustrating a configuration of an electronic endoscope apparatus according to a third embodiment of the present invention.
FIG. 15 is a block diagram illustrating a configuration of an image processing unit.
FIG. 16 is a block diagram illustrating a configuration of an electronic endoscope device according to a modification.
FIG. 17 is a block diagram illustrating a configuration of an electronic endoscope apparatus according to a fourth embodiment of the present invention.
FIG. 18 is a block diagram illustrating a configuration of an electronic endoscope apparatus according to a fifth embodiment of the present invention.
[Explanation of symbols]
1A: Electronic endoscope device
2. Electronic endoscope
3. Light source
4A: Signal processing unit
5 Observation device
6 ... Monitor for observation
7 ... living body
8 ... Insertion part
17 Objective lens
18 ... CCD
19 ... Imaging unit
24 ... Illumination light source
26 ... motor
27 ... Rotary filter
28, 29 ... Filter set
31 ... Filter identification circuit
32 ... Rotary filter switching mechanism
33 ... Control circuit
35 ... CCD driver
41a, 41b, 41c ... memory
42 ... Image processing unit
45 ... Rotary filter switching instruction device
Attorney Susumu Ito

Claims (3)

First illumination light generating means for generating illumination light of a first wavelength band having a narrow half-value width capable of transmitting by a first transmission distance from the subject surface layer portion in the visible light wavelength band,
A second illumination for generating second illumination light having a narrow half-value width that can be transmitted by a second transmission distance from the surface layer of the subject within the visible light wavelength band without overlapping with the first wavelength band. Light generation means;
Imaging means capable of imaging a subject image illuminated with the first illumination light and the second illumination light;
Display means for displaying an object information image representing object information at the first transmission distance and the second transmission distance of the object image based on an output signal of the imaging means;
An object observation device, comprising: R illumination light generating means for generating illumination light in the R wavelength band out of the visible light wavelength band,
G illumination light generating means for generating illumination light of a G wavelength band among the visible light wavelength bands,
B illumination light generating means for generating illumination light in the B wavelength band among the visible light wavelength bands,
A first wavelength band having a half width smaller than the half width of each of the R, G, and B wavelength bands of the visible light wavelength band and capable of transmitting a first transmission distance from the surface of the subject. First illumination light generating means for generating illumination light of
The visible light wavelength band has a half-width narrower than the half-width of each of the R, G, and B wavelength bands, and does not overlap with the first wavelength band. Second illumination light generating means for generating illumination light of a second wavelength band that can be transmitted by a transmission distance,
The visible light wavelength band has a half width smaller than the half width of each of the R, G, and B wavelength bands, and does not overlap with the first and second wavelength bands. Third illumination light generating means for generating illumination light of a third wavelength band that can be transmitted by a third transmission distance,
A first visible subject image illuminated with the illumination light in the R, G, B wavelength bands and a second visible subject image illuminated with the illumination light in the first, second, and third wavelength bands Imaging means capable of imaging
Video signal processing means for generating the first visible subject image and the second visible subject image based on an output signal of the imaging means;
Display means for displaying the first visible subject image and the second visible subject image based on an output signal of the video signal processing means;
An object observation device, comprising: R illumination light generating means for generating illumination light in the R wavelength band out of the visible light wavelength band,
G illumination light generating means for generating illumination light of a G wavelength band among the visible light wavelength bands,
B illumination light generating means for generating illumination light in the B wavelength band among the visible light wavelength bands,
Among the visible light wavelength bands, a first wavelength band having a half width smaller than the half width of each of the R, G, and B wavelength bands and capable of transmitting a first transmission distance from the surface layer of the subject. First illumination light generating means for generating illumination light;
The visible light wavelength band has a half-width narrower than the half-width of each of the R, G, and B wavelength bands, and does not overlap with the first wavelength band. Second illumination light generating means for generating illumination light of a second wavelength band that can be transmitted by a transmission distance,
The visible light wavelength band has a half width smaller than the half width of each of the R, G, and B wavelength bands, and does not overlap with the first and second wavelength bands. Third illumination light generating means for generating illumination light of a third wavelength band that can be transmitted by a third transmission distance,
A first visible subject image illuminated with the illumination light in the R, G, B wavelength bands and a second visible subject image illuminated with the illumination light in the first, second, and third wavelength bands Imaging means capable of imaging
Video signal processing means for generating the first visible subject image and the second visible subject image based on an output signal of the imaging means;
Display means for switching and displaying the first visible subject image and the second visible subject image generated by the video signal processing means based on an output signal level of the imaging means;
An object observation device, comprising:

Images