JP2006122195A - Endoscope optical system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an endoscope optical system capable of obtaining a desired image formation state corresponding to a continuously changing wavelength. <P>SOLUTION: The endoscope optical system includes a spectral transmittance characteristic variable element capable of continuously changing a transmission wavelength in a scope optical system 3. In synchronism with the change of the transmission wavelength by the spectral transmittance characteristic variable element 35, optical elements 37 and 38 provided in the scope optical system 3 or their holding frame 36 can be moved. A spectral transmittance characteristic variable element control means 51 for controlling the spectral transmittance characteristic variable element 35 and a movement control means 52 for controlling the movement of the optical elements provided in the scope optical system 3 or the holding frame are provided, and the optical elements provided in the scope optical system 3 or the holding frame and the spectral transmittance characteristic variable element 35 arranged on one and the same optical system are separately operated. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an endoscope optical system.

In recent years, as an endoscope capable of detecting a plurality of wavelength regions, an endoscope including a spectral transmittance characteristic variable element capable of changing a transmission wavelength in a scope optical system has been disclosed by the present applicant, for example, This is proposed in Patent Document 1.
Conventionally, in an optical system at the distal end portion of an endoscope, a configuration in which an imaging state is changed by moving an optical element is known, for example, as described in Patent Document 2 below.
Conventionally, a camera having a function of adjusting the best image formation position in visible light and infrared light has been proposed in, for example, Patent Document 3 below.
Conventionally, in an endoscope light source device, information on the depth direction of a living body is obtained by irradiating a living body with blue, green, and red light in time series through a bandpass filter having a narrow band wavelength characteristic. The configuration is known as described in Patent Document 4 below.
In addition, as a means for observing the state of tissues and cells in a living body in the past, for example, a probe (endoscope) incorporating a scanning confocal optical system at the tip is inserted into the body, and a built-in cell or the like is inserted. An apparatus for direct observation is proposed in Patent Document 5.
Japanese Patent Application No. 2003-172361 Japanese Patent No. 3186337 DE10207665A1 JP 20048412 A JP 2000-171726 A

However, in the endoscope described in Patent Document 1, the best imaging position changes due to chromatic aberration that occurs when the wavelength used is changed over a wide range. This problem is particularly important in a capsule endoscope optical system with a small number of lenses such as a single lens in order to reduce the size, or an endoscope optical system with a very large number of lenses such as a rigid mirror. This is remarkable in an optical system that is difficult to achieve.
Further, in the endoscope described in Patent Document 1, when the in-vivo pigment is observed with the endoscope described in Patent Document 1, how deep the observed pigment is located in the living body. I can't know.

  In addition, the configuration in which the imaging state is changed by moving the optical element described in Patent Document 2 is such that the imaging state is adjusted with reference to only one wavelength (generally, 587.6 nm). The imaging state cannot be adjusted in accordance with the change in wavelength.

  Further, the adjustment function of the best imaging position in visible light and infrared light in the camera described in Patent Document 3 is a mechanism for inserting and removing the adjustment glass plate into the optical path when the wavelength is switched, It is not suitable for an endoscope distal end where a small diameter is required. In addition, the configuration of Patent Document 3 only adjusts the imaging position in response to switching between only two types of wavelengths, visible light and infrared light. The best imaging position corresponding to each wavelength is not always obtained. In addition, the camera described in Patent Document 3 is difficult to realize because it requires an infinite number of glass plates for adjustment, even when trying to obtain the maximum amount of imaging positions corresponding to a large number of wavelengths that are continuously switched. is there.

  Moreover, in the structure which switches the wavelength of emitted light with the light source device using the bandpass filter of patent document 4, arbitrary wavelengths cannot be irradiated and a wavelength is restrict | limited. In this configuration, in order to increase the number of wavelengths to be selected, it is necessary to increase the number of bandpass filters. Therefore, the apparatus becomes larger and the cost increases. Also, with this configuration, the best imaging position cannot be adjusted in accordance with the change in the emitted wavelength.

  In addition, in the optical system described in Patent Document 5, no contrivance for observing by wavelength is made.

  Thus, conventionally, an endoscope optical system cannot obtain a desired imaging state corresponding to a continuously changing wavelength. Particularly in fluorescence observation, since the fluorescence is very weak light, it is necessary to increase the aperture (NA) of the objective optical system in order to improve the S / N ratio of detection. For this reason, the amount of aberration generated is large, and the observation depth is very small, resulting in a blurred image.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an endoscope optical system capable of obtaining a desired imaging state corresponding to a continuously changing wavelength.

  In order to achieve the above object, an endoscope optical system according to the present invention is an endoscope optical system that includes a spectral transmittance characteristic variable element capable of continuously changing a transmission wavelength in a scope optical system, and the spectral transmittance described above. The optical element provided in the scope optical system or its holding frame can be moved in synchronization with the control of the characteristic variable element.

  In the endoscope optical system according to the present invention, the optical element provided in the scope optical system or its holding frame is moved in synchronization with a change in transmission wavelength by the spectral transmittance characteristic variable element. preferable.

  In the endoscope optical system according to the present invention, the spectral transmittance characteristic variable element control means for controlling the spectral transmittance characteristic variable element, and the movement of the optical element provided in the scope optical system or its holding frame are controlled. It is preferable that the optical element provided in the scope optical system or the holding frame thereof, which has movement control means and is disposed on the same optical system, operates separately from the spectral transmittance characteristic variable element.

  According to the present invention, chromatic aberration can be corrected according to the transmission wavelength, and even if the transmission wavelength is changed, the same subject can be clearly imaged in the best imaging state, and the progress of this wavelength can be improved. A structure that focuses only on the depth desired for observation can be added to the method using the degree, and an endoscope optical system capable of further increasing diagnostic ability in living body observation or the like can be obtained. In addition, by moving the optical element provided in the scope optical system or its holding frame so that the depth of focus becomes shallow, only fluorescence having a desired depth can be clearly observed in the fluorescence observation.

Prior to the description of the embodiments, the effects of the present invention will be described.
If a spectral transmittance characteristic variable element capable of continuously changing the transmission wavelength is used as in the endoscope optical system of the present invention, a plurality of fluorescence wavelengths are detected by separating the fluorescence wavelengths from the fluorescent labeling substance. It becomes possible. By using an air gap variable spectral transmittance characteristic variable element such as an etalon, there are advantages that the entire optical system can be downsized, the wavelength band conversion speed can be increased, and the power consumption can be reduced. In addition, by scanning the peak wavelength of the fluorescence emitted by the fluorescent labeling substance via the variable air gap type spectral transmittance characteristic variable element, a fluorescent labeling substance in which the fluorescence wavelength has a Gaussian distribution in a narrow band can be obtained. When used, the fluorescence wavelength emitted by the fluorescent labeling substance can be detected at high speed and reliably.
Then, as in the endoscope optical system of the present invention, each of the optical elements provided in the scope optical system or its holding frame can be moved in synchronization with the control of the spectral transmittance characteristic variable element. The optical element or the optical element is held in synchronization with the change in the transmission wavelength by the spectral transmittance variable optical element so that each transmission wavelength forms an image on the imaging surface of the imaging element corresponding to the imaging state of the transmission wavelength. By moving the holding frame along the optical path of the transmission wavelength, chromatic aberration can be corrected according to the transmission wavelength, and the same subject can be imaged best even if the transmission wavelength is changed. It is possible to capture images clearly in the state. This effect is particularly effective in correcting the chromatic aberration in an optical system for a capsule endoscope having a small number of lenses such as a single lens or an endoscope optical system having a very large number of lenses such as a rigid mirror in order to reduce the size. This is noticeable in difficult optical systems.

Moreover, according to the endoscope optical system of the present invention, as an example of an observation method, observation can be performed by changing the observation distance for each wavelength. For this reason, there is a method using the advancement of the wavelength in living body observation or the like, but according to the endoscope optical system of the present invention, only the depth desired to be observed by the method using the advancement of the wavelength is used. It is possible to add a structure for focusing, and to further improve the diagnostic ability in living body observation and the like.
Further, according to the endoscope optical system of the present invention, the depth at which observation is desired in the case of performing fluorescence observation by moving the optical element provided in the scope optical system or its holding frame so that the depth of focus becomes shallow. Only the fluorescence of can be clearly observed.

  1A and 1B are explanatory views of the principal part of an endoscope optical system according to an embodiment of the present invention. FIGS. 1A and 1C are graphs showing spectral transmittance characteristics of a spectral transmittance characteristic variable element, FIG. ), (D) are explanatory diagrams showing the optical configuration. In FIG. 1, (a), (b) and (c), (d) have different transmission wavelengths due to the spectral transmittance characteristic variable element. In FIG. 1 (d), for the sake of convenience, illustration of a part of the configuration common to FIG. 1 (b) is omitted. FIG. 2 is a conceptual diagram of a configuration example of a spectral transmittance characteristic variable element applicable to the endoscope optical system of the present invention. FIG. 2A is a schematic configuration diagram of a spectral transmittance characteristic variable element, and FIG. It is a graph which shows the spectral transmittance characteristic of the spectral transmittance characteristic variable element shown to (a). FIG. 3 is a conceptual diagram of another configuration example of a spectral transmittance characteristic variable element applicable to the endoscope apparatus of the present invention. FIG. 3A is a schematic configuration diagram of the spectral transmittance characteristic variable element, and FIG. It is a graph which shows the spectral transmittance characteristic of the spectral transmittance characteristic variable element shown to (a).

The endoscope optical system shown in FIG. 1 includes a variable optical gap spectral transmittance characteristic variable element 35 capable of continuously changing the transmission wavelength in the scope optical system 3. Further, the filter control circuit 51 connected to the spectral transmittance characteristic variable element 35 and the optical element such as the lens 37 and the imaging element 38 provided in the scope optical system 3 or the optical element such as the lens 37 and the imaging element 38 are held. The optical element such as the lens 37 and the image sensor 38, or the lens 37, in synchronization with the change in the transmission wavelength by the spectral transmittance characteristic variable element 35 via the optical system control circuit 52 connected to the holding frame 36. A holding frame 36 holding an optical element such as an image pickup element 38 is configured to move along the optical path of the transmission wavelength. 1 (b) and 1 (d), 4 is a sample, 33 is an objective lens, 39 is a stop, and 34 is an excitation light cut filter. For convenience of explanation, the fiber scope provided in the scope optical system is omitted. 1A and 1C, the broken line indicates the spectral transmittance characteristics of the excitation light cut filter applied to the endoscope apparatus of the first embodiment.
In the endoscope optical system of FIG. 1, the lens 37, the image sensor 38, and the holding frame 36 are configured to be movable. However, when a prism is included as an optical element provided in the scope optical system, The prism may be moved together with these optical elements.

  The variable air gap type spectral transmittance characteristic variable element 35 is composed of an air gap variable etalon. For example, as shown in FIG. 2A, the variable air gap etalon includes reflective films 35Y-1 and 35Y-2 formed on opposing surfaces of two substrates 35X-1 and 35X-2, and the reflective film 35Y. -1 and 35Y-2, an air gap d is provided. Then, multi-beam interference is generated in the incident light from the substrate 35X-1 side, and the wavelength of the maximum transmittance of the emitted light from the substrate 35X-2 side is changed by changing the length of the air gap d. That is, when the air gap d shown in FIG. 2 (a) is changed, the wavelength of the maximum transmittance changes from Ta to Tb as shown in FIG. 2 (b). The air gap can be changed using a piezoelectric element such as a piezoelectric element.

Further, the variable air gap type spectral transmittance characteristic variable element 35 is a type using an electrostatic force manufactured by the surface micro-machining method as a small air gap variable type etalon as shown in FIG. You may comprise.
In the small etalon shown in FIG. 3A, two high-reflectivity half mirrors 35′X-1 and 35′X-2 are arranged to face each other. The opposing surface of the half mirrors 35′X-1 and 35′X-2 is provided with a metal film or a dielectric multilayer film on the surface so that the reflection intensity can be adjusted. Half mirror 35'X-1 is connected to hinge part 35'Z-1 which can be elastically deformed. Half mirror 35'X-2 is being fixed to board | substrate 35'Y-2. The hinge portion 35′Z-1 and the substrate 35′Y-2 are connected to the spacer 35′α with a space therebetween. In addition, in the small etalon of FIG. 3A, an electrostatic force is generated between the opposing half mirrors 35′X-1 and 35′X-2 using a microactuator (not shown) to hinge part 35′Z. -1 is elastically deformed so that the distance between the opposing half mirrors 35'X-1 and 35'X-2 can be changed. The wavelength band to be transmitted can be changed by changing this interval.

Also in the small etalon shown in FIG. 3A, a transmittance peak appears periodically when the air gap is changed at a predetermined interval. The peak scans the wavelength by changing the air gap and moves to a predetermined wavelength.
FIG. 3B is a characteristic diagram showing an example of the relationship between the reference air gap and the air gap when the transmission wavelength reaches a peak in the air gap variable etalon.
When the reference air gap of the etalon is d, the transmission wavelength peaks at (λ / 2) · n (where n is an integer). Therefore, when the reference air gap d is determined, the transmission wavelength reaches a peak when the air gap is (2 / n) d.

Therefore, a plurality of fluorescence wavelengths can be detected in a desired wavelength region by scanning the peak wavelength by controlling the distance between the substrates (air gap) based on the reference air gap with the variable air gap etalon. If such an air gap adjustment using an air gap variable etalon is used, for example, it is possible to detect only a specific wavelength band by separating a fluorescence wavelength from a fluorescent labeling substance in an endoscope apparatus.
Further, the entire optical system can be downsized, the wavelength band conversion speed can be increased, and the power consumption can be reduced.
The air gap control of the variable air gap type spectral transmittance characteristic variable element 35 is performed by a filter control circuit 51.

  Here, when the wavelength of the maximum transmittance of the spectral transmittance characteristic variable element 35 is Ta as shown in FIG. 1A, and the wavelength of the maximum transmittance is Tb as shown in FIG. 1C. Sometimes, the imaging position changes due to the chromatic aberration of the optical system. Despite changing the wavelength in this way, the positions of the optical system and the image sensor are fixed, or the optical image is formed on the image pickup surface of the image sensor 38 according to the image formation state of only one type. If the system or the image sensor is moved, the image pickup surface of the image sensor 38 is not focused and the subject cannot be clearly imaged.

In the endoscope apparatus according to the present embodiment, the optical system control circuit 52 receives the optical element and its position at a position where light of the transmission wavelength forms an image on the imaging surface of the imaging element 38 corresponding to the transmission wavelength in the scope optical system 3. The amount of movement of the holding frame or the like is set in advance. Then, for example, the optical system control circuit 52 synchronizes with the change in the transmission wavelength by the spectral transmittance characteristic variable element 35 via the filter control circuit 51, as shown in FIG. The holding frame 36 holding the optical elements such as 38 or the optical elements such as the lens 37 and the image pickup element 38 is moved to a position where light of each transmission wavelength forms an image on the image pickup surface of the image pickup element 38.
Therefore, according to the endoscope optical system of the present embodiment, even if the transmission wavelength is changed, chromatic aberration can be corrected according to the transmission wavelength, and the same subject can be clearly imaged at the best imaging position. be able to.

FIG. 4 is an explanatory view showing another embodiment of the endoscope optical system of the present invention, where (a) is a conceptual diagram showing the wavelength advancement in a living body, and (b) and (d) are spectral transmittance characteristics. Graphs showing the transmission wavelength characteristics by the variable elements, (c), (e) are explanatory diagrams showing the optical arrangement. In FIG. 4, (b), (c) and (d), (e) have different transmission wavelengths due to the spectral transmittance characteristic variable element.
In the endoscope optical system of the present embodiment, the arrangement and basic actions of the optical members are the same as those of the embodiment shown in FIG. However, the control of the optical element and its holding member by the optical system control circuit (not shown) is different from the embodiment of FIG.

The light that reaches the inside of the living body varies depending on the wavelength, and the longer the wavelength of the light reaches the inside of the living body. Therefore, in the endoscope optical system of the present embodiment, when the transmission wavelength of the spectral transmittance characteristic variable element 35 is controlled through a filter control circuit (not shown) in accordance with a depth desired for observation in a living body, An optical system control circuit (not shown) moves the holding frame 36 holding the optical elements such as the lens 37 and the image sensor 38 so that the best imaging state can be obtained in accordance with the in-vivo progress of the wavelength. Try to change the focal length.
For example, a holding frame that holds optical elements such as the lens 37 and the imaging element 38 is focused on the surface layer of a living body at a short wavelength of 490 nm and focused on, for example, 1 mm from the surface layer at a long wavelength of 700 nm. 36 is moved.
If it carries out like embodiment of FIG. 4, it can observe clearly for every site | part of the different depth in a biological body, and diagnostic ability will improve. It is also necessary to change the wavelength to be detected depending on the site to be diagnosed and the degree of progression of the affected part. In this configuration, unlike a band-pass filter having specific wavelength characteristics, any wavelength can be selected without increasing the size and cost of the apparatus.

  FIG. 5 is an explanatory view showing still another embodiment of the endoscope optical system of the present invention, where (a) is a conceptual diagram showing a fluorescent wavelength band of a fluorescent sample, and (b) and (d) are spectral transmittances. Graphs showing the transmission wavelength characteristics by the characteristic variable element, (c), (e) are explanatory diagrams showing the optical arrangement. In FIG. 5, (b), (c) and (d), (e) have different transmission wavelengths due to the spectral transmittance characteristic variable element.

Also in the endoscope optical system of the present embodiment, the arrangement and basic actions of the optical members are the same as those of the embodiment shown in FIG. However, the control of the optical element and its holding member by the optical system control circuit (not shown) is different from the embodiment of FIG.
The depth of the fluorescent sample can be distinguished by its color (the wavelength of the fluorescence to be observed). Therefore, in the endoscope optical system of the present embodiment, an optical system control circuit (not shown) is used when controlling the spectral transmittance characteristic variable element 35 so as to transmit desired fluorescence through a filter control circuit (not shown). Then, the optical element such as the lens 37 and the image sensor 38 and the holding frame 36 holding them are moved so that the depth of focus becomes shallow. In this way, only fluorescence at a depth desired for observation can be clearly observed.
Further, as a technique for reducing the observation depth, a variable function may be provided in the aperture stop.
In an optical system in which the chromatic aberration is sufficiently corrected and an optical system in which the observation depth is sufficiently widened using a highly sensitive detection element, it is not necessary to adjust the focus for each wavelength. In such an optical system, as shown in FIG. 5 (f), the focus position of the visible region (I) for detecting the reflected light from the living body and the infrared region (II) for detecting the fluorescence from the phosphor. It is only necessary to adjust the focus at two points for each observation mode of the focus position.

  Note that the endoscope optical system of the present invention is not limited to these embodiments. For example, the endoscope optical system can be simply optically scanned with different observation depths at each wavelength. A control circuit may be configured.

Hereinafter, more specific examples of the endoscope optical system of the present invention will be described with reference to the drawings.
FIG. 6 is a schematic configuration diagram illustrating an endoscope apparatus including the endoscope optical system according to the first embodiment of the present invention.
The endoscope apparatus 1 according to the first embodiment includes a light source optical system 2, a scope optical system 3, a processor 5, and a monitor 6. Quantum dots as shown in FIGS. 7 and 8 are preliminarily administered to the living body 4 as a fluorescent labeling substance.

  FIG. 7 is an explanatory diagram showing an example of quantum dots. In FIG. 7, the quantum dot 80 forms a shell layer by coating the surface of ZnS with a microsphere of semiconductor CdSe having a diameter of 2 to 5 nm as a nucleus, for example. Hydroxyl groups are adsorbed on the shell layer via sulfur molecules. A part of this hydroxyl group is bonded to the target protein.

FIG. 8 is a characteristic diagram showing excitation and emission spectra of quantum dots. In FIG. 8, the broken line is the spectral distribution of the excitation light of the quantum dots, and the solid line is the emission spectral distribution of quantum dots made of CdSe and InP having different particle diameters. As shown in FIG. 8, the excitation light is distributed to a region of about 900 nm. The quantum dots emit fluorescence in the near infrared wavelength region. The fluorescence wavelength of quantum dots has the following characteristics compared to the wavelength of conventional fluorescent dyes.
(1) The half-value width of the emission spectrum is about 1/200 (typically 20 to 30 nm) of the center wavelength, and is narrowed to about 1/3 of the fluorescent dye.
(2) The peak wavelength of the emission spectrum can be set relatively freely in the range of about 400 nm to 2000 nm by selecting the size (diameter) and material of the quantum dots. That is, a narrow band Gaussian distribution can be created by setting the material of the quantum dots and adjusting the diameter.
(3) Regardless of the position of the center wavelength of the emission spectrum, the intensity of the excitation spectrum increases in the shorter wavelength side in the visible light to ultraviolet light region.

The light source optical system 2 includes a light source 21, an optional filter 22, and an RGB filter 23. The light source 21 is configured using, for example, a xenon lamp, and emits light in a visible light region and a wavelength region including an excitation wavelength of the fluorescent labeling substance.
The optional filter 22 is provided on the optical path of the light emitted from the light source 21, and limits the transmission wavelength of the light emitted from the light source 21 to light components including the visible light band and the infrared light band. Functions as a band limit filter.

FIG. 9 is an explanatory diagram illustrating a configuration example of the option filter 22 functioning as a band limiting filter in the endoscope apparatus according to the first embodiment, and FIG. 10 is a characteristic diagram illustrating a transmittance characteristic of the option filter 22.
As shown in FIG. 9, the option filter 22 is configured by providing a visible light transmission filter 27X and an infrared light transmission filter 27Y in the circumferential direction of a light-shielding disk. This disk is configured to be rotatable by a rotating shaft 25. And as shown in FIG. 10, the characteristic which inject | emits only the visible region (400-700 nm) light among the light which injected from the light source side, and 650-900 nm red among the wavelength ranges of 600-2000 nm. It has a characteristic of emitting light including outside light.

When the visible light transmission filter 27X is disposed on the optical path, light having a wavelength in the visible region is transmitted as indicated by the characteristic T _VIS in FIG. Further, in the case of arranging the infrared light transmitting filter 27Y on the optical path transmits light of a wavelength in the infrared region as shown in characteristic T _IR of FIG. That is, the option filter 22 has a function of selecting and transmitting either light having a wavelength in the visible region or light having a wavelength in the infrared region by changing the position of the disc on the optical path. As described above, the light from the light source 21 is transmitted by the option filter 22 in the wavelength band from the visible light band to the infrared band of the excitation light.

FIG. 11 is an explanatory diagram showing a configuration example of the rotary filter 23, and FIG. 12 is a characteristic diagram showing the transmittance characteristics of the rotary filter 23.
As shown in FIG. 11, the rotary filter 23 is configured by providing a blue filter 29X, a green filter 29Y, and a red filter 29Z in the circumferential direction of the light-shielding disk, and the visible light blue light (B ), Green light (G), and red light (R). This disk is configured to be rotatable by a rotation shaft 26.
Then, the rotating filter 23 rotates the disk and arranges the blue filter 29X, the green filter 29Y, and the red filter 29Z on the optical path, so that the light of each color of B, G, and R can be obtained as shown in FIG. To Penetrate. In the example of FIG. 11, the blue filter 29X, the green filter 29Y, and the red filter 29Z have characteristics of transmitting light in the infrared region in addition to transmitting light of blue, green, and red wavelengths, respectively. Yes.

Here, referring to the characteristics shown in FIGS. 10 and 12 and the characteristics shown in FIG. 8, the light source optical system 2 can transmit light in any of the visible light region and the infrared light region in FIG. At least a part of the excitation wavelength of the fluorescent labeling substance using the quantum dots as shown is included. The light source optical system 2 outputs light that irradiates at least a part of the wavelength band of 600 nm to 2000 nm to the object to be examined (living body) to which the fluorescent labeling substance is administered. . Here, the wavelength band of 600 nm to 2000 nm has little scattering and absorption in the near-infrared region and excellent depth of penetration, and there are excitation and a plurality of excitation wavelengths in this wavelength region. It conforms to.
In this way, the rotary filter 23 can irradiate the object to be inspected with surface sequential light by rotating the disk.

Returning to FIG. 6, the scope optical system 3 includes a ride guide fiber 31, an illumination lens 32, an objective lens 33, an aperture 39, a lens 37, a fixed filter 34 as an excitation light cut filter, and a variable air gap. And a detector (light receiving unit) 38 using a CCD as an imaging device.
The band wavelength light transmitted through the rotary filter 23 of the light source optical system 2 is transmitted through the light guide fiber 31 and illuminates the living body 4 through the illumination lens 32. As described above, the scope optical system 3 irradiates at least a part of the wavelength band of 600 nm to 2000 nm as the excitation light to the living body 4 that is the object to be inspected. The illumination lens 32 functions as illumination means for the living body 4.

  The objective lens 33 is attached to an observation window (not shown) provided adjacent to the illumination lens 32. Reflected light from the living body 4 illuminated by the illumination lens 32 and fluorescence from the fluorescent labeling substance are incident on the objective lens 33, and an image is formed at the imaging position. This optical image passes through the lens 37, the fixed filter 34, the spectral transmittance characteristic variable element 35, and the lens 37, and is transmitted onto the imaging surface of the light receiving unit 38.

The fixed filter 34 has a spectral transmittance characteristic that transmits the visible light component and the infrared fluorescent wavelength band and blocks the infrared excitation light wavelength band.
The variable air gap type spectral transmittance characteristic variable element 35 is configured using any type of etalon described with reference to FIGS. The spectral transmittance characteristic variable element 35 is connected to the filter control circuit 51.
The lens 37 or the holding frame 36 that holds the lens 37 and the light receiving unit 38 are connected to the optical system control circuit 52. In addition, at least one of the lens 37 or the holding frame 36 that holds the lens 37 and the light receiving unit 38 is configured to be movable on the optical path via the optical system control circuit 52.

  The processor 5 includes a filter control circuit 51, an optical system control circuit 52, a preprocess circuit 53, an A / D converter 54, a video signal processing circuit 55, and a D / A converter 56.

  The filter control circuit 51 controls the alignment and rotation driving of the filters 22 and 23 provided in the light source optical system 2 on the optical path, and is provided in the spectral transmittance characteristic variable element 35 accordingly, for example, a piezoelectric element. The transmission wavelength band is moved by controlling the voltage applied to the. The filter control circuit 51 inputs predetermined control signals to the optical system control circuit 52, the preprocess circuit 53, and the video signal processing circuit 55.

  The optical system control circuit 52 synchronizes with the change information of the transmission wavelength sent as a control signal from the spectral transmittance variable optical element 35, and each transmission wavelength is an image sensor corresponding to the imaging state of each transmission wavelength. The lens 36, the holding frame 37 that holds the lens, or the light receiving unit 38 is moved so as to form an image on the imaging surface of the light receiving unit 38.

  The preprocess circuit 53 is configured to perform preprocessing such as gain adjustment by an amplifier and white balance adjustment of a visible light image by a white balance correction circuit or the like on an image signal input through the light receiving unit 38. ing.

The A / D converter 54 converts the analog image signal input from the preprocess circuit 53 into a digital signal.
The video signal processing circuit 55 stores the signal converted into the digital signal by the A / D converter 54 in an image memory (not shown), and then performs image processing such as image enhancement and noise removal, fluorescence image, normal image, It is configured to perform display control or the like for simultaneous display of character information. Note that the video signal processing circuit 55 can also perform processing for superimposing the fluorescent image and the normal image and normalizing the fluorescent image by calculating between the normal image and the fluorescent image.

The D / A converter 56 converts the digital signal output from the video signal processing circuit 55 into an analog signal.
A video signal output from the D / A converter 56 is input to the monitor 6, and a fluorescent image and a visible light image formed on the imaging surface of the CCD 38 can be displayed on the display surface of the monitor 6. Yes.

An example in which a living body is observed using the endoscope apparatus of the first embodiment configured as described above will be described.
First, the case of performing normal observation will be described. In this case, the visible light transmission filter 27X provided in the option filter 22 shown in FIG. 9 is fixed on the optical path, and transmits visible light and shields infrared light. In this state, when the RGB filter 23 shown in FIG. 11 is rotated at a predetermined rotation speed, the infrared excitation light (IR) is shielded, and light of blue (B), green (G), and red (R) is obtained. The light is sequentially irradiated onto the living body 4 that is the object to be inspected.

In the scope optical system 3 shown in FIG. 6, the drive voltage of the piezoelectric element of the spectral transmittance characteristic variable element 35 is set to V ₀ . In the first embodiment, when the drive voltage is V ₀ , the peak position in the visible light band of the transmittance peak of the spectral transmittance characteristic variable element 35 that is periodically generated is represented by the illumination light B, G, R. It is made to almost coincide with the center wavelength. Therefore, in a state where the driving voltage V ₀ is constant, the light receiving surface of the detector 38 serving as an image sensor corresponds to the illumination light to the living body, blue (B) and fluorescence (IR ₀ ), green (G) and fluorescence. A light image of wavelength components of (IR ₀ ), red (R) and fluorescence (IR ₀ ) is received.

  The light image received by the detector 38 is photoelectrically converted to R, G, B color component image signals and input to the processor 5. After the signal processing is performed by the processor 5 as described above, a normal endoscopic image by visible light is displayed on the monitor 6.

  Next, an example in which a fluorescent image and a normal image are observed simultaneously will be described. In this case, for example, the visible light transmission filter 27X of the option filter 22 transmits visible light in the first frame, and the infrared light is transmitted by the infrared transmission filter 27Y in the subsequent frame, so that the option filter 22 is 1 Rotate. For this reason, the optional filter 22 is in a state of alternately transmitting visible light and infrared light.

  In this state, the RGB filter 23 is rotated at 1/3 the number of rotations of the option filter 22. That is, the band limiting filter 22 rotates once, and the blue (B) filter 29X is fixed on the optical path in a state in which visible light and infrared light are alternately transmitted, and the transmitted light is irradiated onto the object to be inspected. Similarly, with the option filter 22 rotating once and transmitting visible light and infrared light alternately, the green (G) filter 29Y and the red (R) filter 27Z are fixed on the optical path and transmitted. Irradiate the object under test with light.

Here, in the scope optical system shown in FIG. 6, the spectral transmittance characteristic variable element 35 in a state where the visible light is transmitted by the option filter 22 and the blue (B) filter is fixed on the optical path by the RGB filter 23. The drive voltage of the piezoelectric element is set to V ₀ which is the same as that during normal observation. The drive voltage in a state where infrared light is transmitted through the option filter 22 is set to V ₁ .

Next, when the green (G) filter is fixed on the optical path by the RGB filter 23 and the visible light is transmitted by the option filter 22, the driving voltage is set to V _0, and the infrared light is transmitted by the option filter 22. the driving voltage of the state and V _2.
In addition, the drive voltage in a state where visible light is transmitted through the option filter 22 in a state where the red (R) filter is fixed on the optical path by the RGB filter 23 is V _0, and infrared light is transmitted through the option filter 22. The driving voltage in the state is V ₃ .
The drive voltage for controlling the spectral transmittance characteristic variable element 35 is set to V ₀ ≠ V ₁ ≠ V ₂ ≠ V _3, and the transmission bands at the respective drive voltages are made different.

A fixed filter 34 that blocks excitation light is disposed in front of the light receiving surface of the detector 38. As a result, blue (B) and fluorescence (IR ₀ ), fluorescence (IR ₁ ), green (G) and fluorescence (IR ₀ ) are sequentially applied to the light receiving surface of the detector 38 in accordance with the irradiation light on the living body. , Fluorescence (IR ₂ ), red (R), fluorescence (IR ₀ ), and images of only the wavelength components of fluorescence (IR ₃ ) are received. The drive voltage for controlling the spectral transmittance characteristic variable element 35 is set to V ₀ ≠ V ₁ ≠ V ₂ ≠ V _3, and the transmission bands at the respective drive voltages are made different. The band is IR ₀ ≠ IR ₁ ≠ IR ₂ ≠ IR ₃ . Therefore, three types of visible light images of blue, green, and red and three types of fluorescent images of IR ₁ , IR ₂ , and IR ₃ are obtained. Thus, in fluorescence observation, fluorescence wavelengths from three different types of quantum dots can be separated and extracted.

  Thus, when simultaneously observing the fluorescent image and the normal light image, the option filter 22 and the RGB filter 23 are controlled to rotate in synchronization with a certain period. Further, the drive voltage of the piezoelectric element of the spectral transmittance characteristic variable element 35 is controlled in synchronization with the option filter 22 and the RGB filter 23. In addition, the detector 38 receives visible light of blue, green, red, or infrared fluorescence according to the positions of the RGB filter 23 and the option filter 22. The output signal of the detector 38 is signal-processed by the processor 5 and a fluorescent image and a normal observation image are displayed on the monitor 6.

During this observation process, in the endoscope optical system of the present embodiment, the optical system control circuit 52 is in an imaging state that is different for each transmission wavelength in synchronization with a change in the wavelength transmitted through the spectral transmittance characteristic variable element 35. Correspondingly, the lens 37, the detector 38, or the holding frame 36 that holds the lens 37 is placed on the optical axis so that the light of each wavelength forms an image on the imaging surface of the detector 38 with the chromatic aberration corrected. Move in the direction. The actual movement is performed by driving means such as a motor (not shown) connected to the optical system control circuit 52.
For this reason, even if the transmission wavelength is changed by the spectral transmittance characteristic variable element 35, the chromatic aberration can be corrected according to the transmission wavelength, and the same subject can be clearly imaged.

  Note that the processor 5 calculates or counts the peak wavelength of fluorescence by dividing the spectral transmittance by wavelength, and displays a pseudo color display on the display image according to the count number. Further, by dividing or dividing the transmittance according to wavelength, the peak wavelength emitting fluorescence is calculated or counted, and a fluorescence peak wavelength versus protein table (not shown) in a memory provided in the processor 5 is referred to. In addition to identifying in vivo proteins, the identified proteins are stored in memory as data. As described above, if pseudo-color display is performed on the display image in accordance with the count number, the current state of a lesion such as cancer can be reliably observed without error. In addition, individual in vivo protein data can be read from the memory at any time, and used for diagnosis or the like in comparison with the fluorescence peak wavelength to protein table data as a reference.

  In addition, as shown in FIG. 8, the fluorescence wavelength of the quantum dots used for the fluorescent labeling substance can create a narrow band Gaussian distribution by adjusting the material and the outer diameter. For example, as a blue series, CdSe nanocrystals are used, and each outer diameter is 2.1, 2.4, 3.1, 3.6, 4.6 nm. In the green series, InP nanocrystals are used, and the diameters are 3.0, 3.5, and 4.6 nm. In the red series, InAs nanocrystals are used and the diameters are 2.8, 3.6, 4.6, and 6 nm.

  In Example 1, as a fluorescent labeling substance (tag), the material is CdSe, InP, InAs, and the outer diameter is in the range of 2.1 to 6.6 nm, according to the number of living bodies (proteins) to be detected. You may utilize the quantum dot which changed multiple diameters. Quantum dots having a plurality of outer diameters are synthesized so as to have hydrophilicity, antibody characteristics, and biocompatibility, respectively. As a premise, it is desirable to optimize the material and the outer diameter, and set the spectral characteristics within the conditions of infrared excitation and infrared fluorescence.

  By using quantum dots as described above, a fluorescent labeling substance (tag) can be administered, irradiated with light, and fluorescence in the near-infrared wavelength region can be extracted to the outside of the living body. But it can be observed accurately. For this reason, early cancer can be diagnosed by using a fluorescent labeling substance administered to a living body. In addition, a high degree of diagnostic ability by the endoscope apparatus is possible. Quantum dots have the characteristics that they can be observed under a microscope for 1 hour or longer, have a long fluorescence lifetime, and have a bright fluorescence. Further, since the excitation light is substantially limited to the infrared light region in the deep part of the living body, the infrared light band-pass filter is unnecessary on the light source side. In addition, in the quantum dot, each fluorescence wavelength has a Gaussian distribution in a narrow band, and is suitable for characteristics detected by an etalon type bandpass filter.

  Further, as described above, the light that reaches inside the living body varies depending on the wavelength. Therefore, in the endoscope optical system of the present embodiment, when the transmission wavelength of the spectral transmittance characteristic variable element 35 is controlled via the filter control circuit 51 in accordance with the depth desired to be observed in the living body, the optical system The control circuit 52 moves the optical elements such as the lens 37 and the image sensor 38 and the holding frame 36 holding these optical elements so that the best imaging state is achieved in accordance with the in-vivo progress of the wavelength. The in-focus distance may be changed. In this way, it is possible to clearly observe each part at a different depth in the living body, and the diagnostic ability is improved.

Further, as described above, the depth of the fluorescent sample can be distinguished by its color (the wavelength of the fluorescence to be observed). Therefore, in the endoscope optical system of the present embodiment, when controlling the spectral transmittance characteristic variable element 35 so as to transmit desired fluorescence through the filter control circuit 51, the optical system control circuit 52 is used. The lens 37, the optical element such as the image sensor 38, and the holding frame 36 holding these may be moved so that the depth of focus becomes shallow. In this way, only fluorescence at a depth desired for observation can be clearly observed.
Further, as a technique for reducing the observation depth, a variable function may be provided in the aperture stop.
In an optical system with sufficiently corrected chromatic aberration and an optical system with a sufficiently wide observation depth, it is not necessary to adjust the focus for each wavelength. In such an optical system, as shown in FIG. 5 (f), the focus position of the visible region (I) for detecting the reflected light from the living body and the infrared region (II) for detecting the fluorescence from the phosphor. It is only necessary to adjust the focus at two points for each observation mode of the focus position. Thereby, control can be simplified.

The fluorescent labeling substance may be any substance that emits a plurality of different fluorescences in the near infrared region, and is not limited to quantum dots.
Another example is an organic fluorescent dye. FIG. 17 is a characteristic diagram showing absorption and fluorescence spectra of organic fluorescent dyes “Alexa Fluor647” and “Alexa Fluor680” manufactured by MolecularProbes.
In the figure, the solid line shows the absorption spectrum of Alexa Fluor647, the dotted line shows the fluorescence spectrum of Alexa Fluor647, the one-dot chain line shows the absorption spectrum of Alexa Fluor680, and the two-dot chain line shows the fluorescence spectrum of Alexa Fluor680. The shaded area indicates the wavelength of the excitation light. As shown in the figure, by using excitation light having a wavelength in the vicinity of 620 nm, two types (Alexa Fluor647, Alexa Fluor680) of different wavelengths of fluorescence can be obtained in the near infrared wavelength region. Not only quantum dots but also fluorescent dyes having such characteristics may be used as fluorescent labeling substances for very early cancer diagnosis.

FIG. 13: is a schematic block diagram which shows the principal part of the capsule endoscope apparatus provided with the endoscope optical system concerning Example 2 of this invention.
The capsule endoscope apparatus 94 according to the second embodiment includes an LED 90 instead of the light source device 2 and the light guide 31 inside the apparatus main body, a power source is configured by a battery (or a capacitor) 91, and a detected signal is further transmitted. The point which transmits to the external apparatus 95 by radio | wireless using the antenna 92 differs greatly from the endoscope apparatus of Example 1 shown in FIG.
The capsule endoscope device 94 is provided with a control circuit 5, a power supply 96 using a capacitor or a battery, a coil 91 electrically connected to the power supply 96, a position control magnet 93, and an antenna 92. ing. In addition, the capsule endoscope apparatus 94 irradiates the living body with the emitted light from the LED 90 through the transparent cover 97, and introduces the reflected light or fluorescence into the lens 37.
The coil 91 charges the capacitor of the power source 96 or charges the battery by causing a current to flow by magnetic induction when the position control magnet 93 is magnetized by external magnetic lines of force. The position control magnet 93 is an energy source for moving the capsule endoscope device 94 by external electromagnetic waves. The antenna 92 transmits the detection signal of the detector 38 to the external device 95.
The external device 95 is provided with an antenna 95a, a monitor 95b, and a control circuit (not shown). The antenna 95 a receives a signal transmitted from the antenna 92 of the capsule endoscope apparatus 94 and transmits electromagnetic waves, that is, magnetic energy, to the position control magnet 93. The monitor 95b displays an image formed via a control circuit (not shown) based on the detection signal of the detector 38 transmitted from the antenna 92 and received by the antenna 95a.
Other configurations and operational effects are almost the same as those of the endoscope apparatus of the first embodiment.
In the capsule endoscope apparatus according to the second embodiment, a single lens 37 is configured to reduce the size. For this reason, chromatic aberration cannot be corrected sufficiently. Accordingly, it is necessary to always perform focus adjustment when detecting different wavelengths in all the visible region (I) and infrared region (II). However, according to the capsule endoscope apparatus of the second embodiment, the focus adjustment can always be performed when detecting different wavelengths, so that a sharp image that is always in focus can be obtained.

The endoscope apparatus according to the third embodiment is different from the endoscope apparatus according to the first embodiment in the configuration of the option filter 22 and the rotary filter 23 of the light source device 2.
Specifically, the openings 27X and 27Y of the option filter shown in FIG. 9 are used as a through window without installing a band limiting filter. Further, the openings 29X, 29Y, and 29Z of the rotary filter shown in FIG. 11 are also used as a through window without installing a band limiting filter. Other configurations and operations are almost the same as those of the endoscope apparatus according to the first embodiment, and thus, reflected light from a living body can be acquired for each wavelength and in the depth direction at the same time.
According to the endoscope device of the third embodiment, visible light (white light) can be pulsed in time series from the light source device 2. Then, the transmission characteristic of the wavelength tunable filter is changed in synchronization with the driving of the rotary filter, and focus adjustment is performed according to the wavelength characteristic. Thus, if an electrical signal is transferred from the image sensor 38 to the processor 5 during the light shielding period of the rotary filter, the function of the element sitter can be omitted from the image sensor 38, and the choices of usable image sensors can be expanded.
In the case of observation of visible light such as R, G, and B, the visible transmission filter band limiting filter T _VIS shown in FIG. 10 may be disposed in the opening 27X or 27Y of the optional filter. Thereby, an inexpensive light guide with low heat resistance such as plastic can be used.

FIG. 14: is a schematic block diagram which shows the principal part of the endoscope apparatus provided with the endoscope optical system concerning Example 4 of this invention.
The endoscope apparatus according to the fourth embodiment is different from the endoscope apparatus according to the third embodiment in that the option filter 22 and the rotary filter 23 of the light source device 2 illustrated in FIG. 6 are omitted.
Other configurations and operations are substantially the same as those of the endoscope apparatus according to the third embodiment, and thus, reflected light from a living body can be acquired for each wavelength and in the depth direction at the same time. In particular, any wavelength can be selected by the wavelength tunable spectroscopic element.
According to the endoscope apparatus of the fourth embodiment, visible light (white light) can always be emitted from the light source device 2. Then, the transmission characteristic of the wavelength tunable filter is changed in synchronization with the element shutter of the image sensor 38, and focus adjustment is performed according to the wavelength characteristic. Thereby, the functions of the option filter and the rotary filter can be omitted from the light source device 2, and the light source device can be reduced in size and cost.
In the case of observation of visible light such as R, G, and B, a visible transmission filter band limiting filter T _VIS shown in FIG. 10 may be disposed between the light path of the light source 21 and the light guide 31. Thereby, an inexpensive light guide with low heat resistance such as plastic can be used.

FIG. 15 is a schematic configuration diagram illustrating a main part of an endoscope apparatus including an endoscope optical system according to a fifth embodiment of the present invention.
The endoscope apparatus according to the fifth embodiment is different from the endoscope apparatus according to the first embodiment in the configuration from the objective lens 33 to the detector 38 of the scope optical system 3.
Specifically, the scope optical system 3 includes, in order from the living body 4 toward the detector 38, an objective lens 37, a fixed filter 34, a spectral transmittance characteristic variable element 35, a single fiber 31 ′ for image guide, It has a lens 37 ′ and a detector 38. Other configurations and operational effects are almost the same as those of the endoscope apparatus of the first embodiment.
The scope optical system 3 according to the fifth embodiment is a confocal optical system in which the core of the single fiber 31 ′ serves as a pinhole. Thereby, a small confocal optical system capable of obtaining a stereoscopic image including the wavelength characteristics of a living body can be realized by independently performing the transmittance characteristic of the spectroscopic element and the focus adjustment by the lens holding frame. In addition, although the lens 37 is one piece in the figure, the structure which consists of several pieces may be sufficient.

FIG. 16: is a schematic block diagram which shows the principal part of the endoscope apparatus provided with the endoscope optical system concerning Example 6 of this invention, The endoscope apparatus of Example 5 is a fixed filter 34, The arrangement of the spectral transmittance characteristic variable element 35 is different.
Specifically, the scope optical system 3 includes an objective lens 37, an image guide single fiber 31 ', a lens 37', a fixed filter 34, and a spectral transmittance characteristic in order from the living body 4 toward the detector 38. The variable element 35, the lens 37 ", and the detector 38 are configured. The other configurations and operational effects are substantially the same as those of the endoscope apparatus of the first embodiment.
According to the scope optical system 3 of the endoscope apparatus of the sixth embodiment, the probe tip can be downsized.

In these embodiments, the optical element or the holding frame for holding the optical element is provided with light of each transmission wavelength corresponding to the imaging state by the fluorescence wavelength in the infrared region that passes through the spectral transmittance characteristic variable element. Is moved so as to form an image on the imaging surface of the imaging device, but if the wavelength passing through the spectral transmittance characteristic variable element is different, in addition to the light of the wavelength in the infrared region used as the fluorescence wavelength, For visible light such as R, G, and B, light of each transmitted wavelength may be configured to form an image on the imaging surface of the imaging element in accordance with the imaging state of each wavelength. In this case, a clear image in which chromatic aberration is corrected in normal color observation can be obtained.
Further, as a technique for reducing the observation depth, a variable function may be provided in the aperture stop.
In an optical system with sufficiently corrected chromatic aberration and an optical system with a sufficiently wide observation depth, it is not necessary to adjust the focus for each wavelength. In such an optical system, there are two points for each observation mode: the focus position in the visible region (I) for detecting reflected light from the living body and the focus position in the infrared region (II) for detecting fluorescence from the phosphor. You can just adjust the focus. Thereby, control can be simplified.

It is principal part explanatory drawing of the endoscope optical system concerning one Embodiment of this invention, (a), (c) is a graph which shows the spectral transmittance characteristic of a spectral transmittance characteristic variable element, (b), ( d) is an explanatory view showing an optical configuration. It is a conceptual diagram of a configuration example of a spectral transmittance characteristic variable element applicable to the endoscope optical system of the present invention, (a) is a schematic configuration diagram of a spectral transmittance characteristic variable element, (b) is (a) It is a graph which shows the spectral transmittance characteristic of the spectral transmittance characteristic variable element shown in FIG. It is a conceptual diagram of another configuration example of the spectral transmittance characteristic variable element applicable to the endoscope apparatus of the present invention, (a) is a schematic configuration diagram of the spectral transmittance characteristic variable element, (b) is (a) It is a graph which shows the spectral transmittance characteristic of the spectral transmittance characteristic variable element shown in FIG. It is explanatory drawing which shows other embodiment by the endoscope optical system of this invention, (a) is a conceptual diagram which shows the wavelength progress in a living body, (b), (d) is by a spectral transmittance characteristic variable element Graphs showing transmission wavelength characteristics, (c) and (e) are explanatory diagrams showing optical arrangements. It is explanatory drawing which shows other embodiment by the endoscope optical system of this invention, (a) is a conceptual diagram which shows the fluorescence wavelength range of a fluorescence sample, (b), (d) is a spectral transmittance characteristic variable element (C), (e), (f) is an explanatory view showing an optical arrangement. 1 is a schematic configuration diagram illustrating an endoscope apparatus including an endoscope optical system according to Embodiment 1 of the present invention. It is explanatory drawing which shows the example of a quantum dot. It is a characteristic view which shows the excitation and emission spectrum of a quantum dot. It is explanatory drawing which shows one structural example of the option filter 22 which functions as a band-limiting filter in the endoscope apparatus of Example 1. FIG. 6 is a characteristic diagram showing a transmittance characteristic of the option filter 22. FIG. 3 is an explanatory diagram illustrating a configuration example of a rotary filter 23 in the endoscope apparatus according to the first embodiment. FIG. 6 is a characteristic diagram showing a transmittance characteristic of the rotary filter 23. It is a schematic block diagram which shows the capsule endoscope apparatus provided with the endoscope optical system concerning Example 2 of this invention. It is a schematic block diagram which shows the endoscope apparatus provided with the endoscope optical system concerning Example 4 of this invention. It is a schematic block diagram which shows the principal part of the endoscope apparatus provided with the endoscope optical system concerning Example 5 of this invention. It is a schematic block diagram which shows the principal part of the endoscope apparatus provided with the endoscope optical system concerning Example 6 of this invention. It is a characteristic view which shows the excitation and light emission intensity of an organic fluorescent dye.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Endoscope apparatus 2 Light source optical system 3 Endoscope end part (scope optical system)
4 Living body 5 Processor 6 Monitor 21 Light source 22 Optional filter 23 Rotation filter (RGB filter)
25, 26 Rotating shaft 27X Visible light transmission filter 27Y Infrared light transmission filter 29X Blue filter 29Y Green filter 29Z Red filter 31 Light guide fiber 31 'Single fiber for image guide 32 Illumination lens 33 Objective lens 34 Fixed filter 35 Spectral transmittance characteristic Variable element 35X-1, 35X-2, 35'Y-2 Substrate 35Y-1, 35Y-2 Reflective film 35'X-1, 35'X-2 Half mirror 35'Z-1 Hinge portion 35'α Spacer 36 Holding frame 37, 37 ', 37 "Lens 38 Detector (imaging device)
51 Filter Control Circuit 52 Optical System Control Circuit 53 Pre-Process Circuit 54 A / D Converter 55 Video Signal Processing Circuit 56 D / A Converter 80 Quantum Dot 90 LED
91 Battery or Capacitor 92 Antenna 93 Magnet for Position Control 94 Capsule Endoscope Device 95 External Device 95a Antenna 95b Monitor 96 Power Supply 97 Transparent Cover

Claims (3)

An endoscope optical system including a scope optical system including a spectral transmittance characteristic variable element capable of continuously changing a transmission wavelength,
An endoscope optical system characterized in that an optical element provided in the scope optical system or a holding frame thereof can be moved in synchronization with the control of the spectral transmittance characteristic variable element. 2. The endoscope optical according to claim 1, wherein an optical element provided in the scope optical system or a holding frame thereof is moved in synchronization with a change in transmission wavelength by the spectral transmittance characteristic variable element. system. Spectral transmittance characteristic variable element control means for controlling the spectral transmittance characteristic variable element, and movement control means for controlling the movement of the optical element provided in the scope optical system or its holding frame, which are arranged on the same optical system The endoscope optical system according to claim 1, wherein an optical element provided in the scope optical system or a holding frame thereof and the spectral transmittance characteristic variable element operate separately.