WO2019124739A1

WO2019124739A1 - Multi-image endoscope system

Info

Publication number: WO2019124739A1
Application number: PCT/KR2018/013708
Authority: WO
Inventors: 배영민; 진승오; 강동구; 신기영; 김명준; 이원주; 이치원; 장민혜
Original assignee: 한국전기연구원
Priority date: 2017-12-21
Filing date: 2018-11-12
Publication date: 2019-06-27

Abstract

Disclosed is a multi-image endoscope system. The multi-image endoscope system comprises a time-division light source unit, an image detection unit, an image processing unit, and a control unit. The time-division light source unit radiates light in preset different wavelength ranges into samples, respectively, for a preset time, the image detection unit detects an image emitted from the sample, the image processing unit processes the detected image, and the control unit synchronizes the time-division light source unit with at least one of the image processing unit and the image detection unit.

Description

Multiple imaging endoscopy system

The present invention relates to an endoscope system, and more particularly, to an endoscope system capable of acquiring multiple images such as a white light image, a fluorescent image, and a spectroscopic image.

BACKGROUND ART [0002] In medical optical imaging devices such as endoscopes, imaging techniques for improving contrast of lesions are being developed in addition to techniques for improving image resolution.

In addition to white light imaging techniques that show the surface structure of existing tissues, spectral imaging techniques that show the spectral characteristics of tissues as contrasts, fluorescence imaging (fluorescence imaging) ) Technology is being introduced as an endoscopic imaging technique.

Particularly, in the fluorescence imaging technique, there are developed techniques for imaging by image contrast such as autofluorescence of human tissue or induction fluorescence caused by binding of fluorescent molecules injected through blood vessels to tissues.

1 is a view schematically showing the structure of a white light imaging apparatus. Fig. 1 shows a configuration of a general white light optical imaging apparatus. To obtain a white light image, a sample is irradiated with white light having a broadband spectrum in the sample, and light reflected from the sample is detected and imaged.

Reflections from the specimen include mirror reflections at the surface, diffusion, and scattering from the interior. Generally, when white light is irradiated, the reflected light is also white light, and a color image can be obtained by using a color camera.

On the other hand, the spectroscopic imaging apparatus is a device for observing the reflection characteristic of the sample with respect to narrowband light. 2 and 3 are views schematically showing the structure of a spectroscopic imaging apparatus. Similar to the white light imaging device, it consists of a light source and a camera for imaging.

FIGS. 2 and 3 show a method (FIG. 2) of irradiating a sample with narrowband light to detect and imaging reflected light (FIG. 2); and a method of transmitting only a narrow band of the reflected light from a sample (See FIG. 3) are shown. Particularly, the image information of the sample is obtained by using a plurality of wavelength bands of the narrowband light to be inspected.

A fluorescence imaging apparatus is a device for detecting and imaging an emission light emitted from a fluorescent molecule due to a fluorescence phenomenon existing in a sample. 4 is a view schematically showing a structure of a fluorescence imaging apparatus. Fig. 4 shows the structure of a typical fluorescence imaging apparatus.

In order to obtain a fluorescence image, an excitation light for exciting the fluorescent molecule and a detector for detecting the emission light emitted from the fluorescent molecule are required and can be implemented in various ways.

First, a sample having a fluorescent molecule is irradiated with light (excitation light) in a wavelength band capable of exciting fluorescent molecules. For this purpose, an optical system capable of irradiating only a narrow backlight such as a bandpass filter or a monochrometer can be used.

When the excitation light is illuminated, the emitted light of a wavelength band longer than the excitation light due to the fluorescence phenomenon of the fluorescent molecule contained in the sample is emitted from the fluorescent molecule and mixed with the reflected light of the sample.

In order to obtain fluorescence images, the emitted light must be detected and imaged by a detector. For this purpose, an emission light filter or a monochrometer is inserted into the detector in order to block light in a wavelength band other than the emitted light.

Various inventions for application to an endoscope system for inspecting the internal tissues of the human body by inserting a white light image, a spectroscopic image and a fluorescence image into the human body have been derived as described above.

In order to apply the structure of such an optical imaging apparatus to an endoscope, an irradiation optical system for irradiating light to the sample and an imaging optical system for detecting and imaging the reflected light must be integrated into an endoscope, and various structures have been proposed.

However, these structures are successful in acquiring each image, but the structure of the optical system is complicated and has limitations in providing multiple images quickly.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an endoscope system capable of providing multiple images quickly while simplifying the structure of an optical system.

In order to accomplish the above object, a multi-image endoscopic system according to the present invention includes a time division light source unit, an image detection unit, an image processing unit, and a control unit. The time-divisional light source unit irradiates light of a predetermined wavelength range to the sample for a predetermined time, the image detector detects an image emitted from the sample, the image processor processes the detected image, and the controller controls the time- And synchronizes with at least one of the detection unit and the image processing unit.

According to such a configuration, since the light source unit is used in synchronism with at least one of the image processing unit and the image detecting unit, the image processing apparatus corresponding to different wavelength regions are not required to be provided in the endoscope system in order to obtain multiple images, It is possible to provide multiple images quickly while simplifying the structure of the optical system.

In this case, the time-divisional light source section includes a broadband light source having a predetermined wide-band wavelength region and a plurality of wavelength selection sections each transmitting a predetermined wavelength region in the wide-band wavelength region, You can choose more than one. According to this configuration, a time-divisional light source can be provided using a wideband light source.

The time-divisional light source unit may include a plurality of narrowband light sources having a preset narrowband wavelength range, and the controller may select one or more of the plurality of narrowband light sources for a preset time. According to this configuration, it is possible to provide a time-divisional light source using a narrowband light source.

The time-divisional light source section includes a narrow-band light source having a predetermined narrow-band wavelength region and a plurality of wavelength conversion sections for converting a narrow-band wavelength region into another predetermined narrow-band wavelength region, One or more of the wavelength conversion sections of the wavelength conversion section can be selected.

According to such a configuration, since light of various wavelengths can be generated using only a small number of narrowband light sources, the structure of the optical system can be simplified while increasing the light output efficiency.

At this time, the plurality of wavelength converters may each include nanoparticles of predetermined substances of different sizes. According to this structure, by changing the size of the nanomaterial particles, it is possible to easily implement a wavelength conversion unit having high light output efficiency corresponding to various wavelengths.

Further, the image detecting unit may include a light transmission filter for passing a predetermined wavelength region of fluorescence. According to this configuration, it is possible to acquire multiple images including a fluorescent image as well as a white light image and a spectroscopic image.

At this time, the light transmission filter can be set so as to exclude the wavelength region of the excitation light set in advance. According to such a configuration, it is possible to acquire multiple images including fluorescence images without impairing the performance of the white live image or the spectroscopic image.

In addition, the time interval of the predetermined time at which one or more of the light source unit, the image processing unit, and the image detecting unit are synchronized can be changed. According to such a configuration, it is possible to obtain an optimum image for each wavelength region by adjusting the time interval according to the wavelength region.

According to the present invention, since the light source, the image processing unit and the image detecting unit are used in synchronism with each other in time division, it is not necessary to provide all the image processing apparatuses corresponding to different wavelength regions in the endoscope system in order to obtain multiple images. It is possible to provide multiple images quickly while simplifying them.

In addition, a time-divisional light source can be provided using a broadband light source.

In addition, a time-divisional light source can be provided using a narrowband light source.

In addition, since light of various wavelengths can be generated using only a small number of narrowband light sources, the structure of the optical system can be simplified while increasing the light output efficiency.

Also, by changing the size of the nanomaterial particles, it is possible to easily implement a wavelength conversion unit having a high light output efficiency corresponding to various wavelengths.

In addition, it is possible to acquire multiple images including fluorescence images as well as white live images or spectroscopic images.

In addition, it is possible to acquire multiple images including fluorescence images without hindering the performance of the white live image or the spectroscopic image.

Further, by adjusting the time interval according to the wavelength region, an optimum image can be obtained for each wavelength region.

1 schematically shows the structure of a white light imaging device;

Fig. 2 and Fig. 3 are diagrams schematically showing a structure of a spectroscopic imaging apparatus. Fig.

4 is a view schematically showing the structure of a fluorescence imaging apparatus;

5 is a schematic block diagram of a multi-imaging endoscopic system according to an embodiment of the present invention.

6 and 7 schematically illustrate the structure of a time division light source using a broadband light source.

8 is a view schematically showing the structure of a time division light source using a plurality of narrowband light sources.

9 is a view schematically showing the structure of a time division light source using wavelength conversion of a narrowband light source.

FIG. 10 schematically shows an example of detecting an image emitted by a light irradiated from a time division light source using a color camera module or a mono camera module; FIG.

11 is a view showing characteristics of a light transmission filter having a transmittance characteristic excluding only an excitation light wavelength band.

12 is a view showing a transmission characteristic of a general emission image light emission filter.

13 is a view showing an embodiment for acquiring a white light image, a spectroscopic image, and a fluorescence image using light irradiated using a time division light source.

Figs. 14 and 15 are diagrams showing examples of positions of the light transmission filter; Fig.

16 is a diagram showing an example of a time synchronization signal of the control unit;

17 illustrates an example in which the time division light source unit is synchronized with the image detection unit.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

5 is a schematic block diagram of a multi-imaging endoscopic system 100 according to an embodiment of the present invention. 5, the multi-image endoscopic system 100 includes a time-divisional light source unit 110, an image detection unit 120, an image processing unit 130, and a control unit 140. 5, the time division light source unit 110, the image detection unit 120, the image processing unit 130, and the control unit 140 are respectively implemented as a time division light source, a camera module, a video processor, and a time- 120 includes a light transmission filter 122.

The time-divisional light source unit 110 irradiates the specimen with light having a predetermined wavelength range in advance for a predetermined time. In order to obtain a white light image, a spectroscopic image, and a fluorescence image, light having spectral characteristics corresponding thereto must be irradiated on the sample. For example, a white light image should emit light in the entire visible wavelength range, a spectral image should emit light in the spectral wavelength band to be observed, and a fluorescence image should emit light in the excitation wavelength band to excite the fluorescent molecules of the sample Should be able to. The time-division light source unit 110 generates light having various spectral characteristics.

In this case, the time-divisional light source unit 110 includes a broadband light source 112 having a predetermined wide-band wavelength region and a plurality of wavelength selection units 114 each transmitting a predetermined wavelength region in a wide-band wavelength region, 140 may select one or more of the plurality of wavelength selectors 114 for a predetermined time.

6 and 7 are views schematically showing the structure of a time division light source using a broadband light source. 6 and 7 show a structure in which an optical filter (narrow-band-pass filter) or a monochrometer is used for the wavelength selector 114 to generate light of a desired wavelength band from the broadband light source 112, respectively. At this time, the wavelength selector 114 may have a filter wheel structure having a plurality of filters to generate multiple wavelengths, and an appropriate filter may be selected through the controller 140. [

The time divisional light source unit 110 includes a plurality of narrowband light sources 116 having a preset narrowband wavelength region and the controller 140 controls one or more of the plurality of narrowband light sources 116 Can be selected. 8 is a view schematically showing a structure of a time division light source using a plurality of narrowband light sources. 8 shows a structure in which a plurality of narrowband light sources 116 are combined using an optical system such as a mirror and a lens. At this time, various wavelength bands can be created through the control of the respective light sources 116.

The time-divisional light source unit 110 further includes a narrow-band light source 116 having a predetermined narrow-band wavelength region and a plurality of wavelength conversion units 118 for converting a narrow-band wavelength region into another predetermined narrow-band wavelength region And the controller 140 may select one or more of the plurality of wavelength converters 118 for a preset time.

9 is a view schematically showing the structure of a time division light source using wavelength conversion of a narrowband light source. 9, when the narrowband light source 116 and the wavelength converter 118 are used, the wavelength band of the narrowband light source 116 can be shifted to a desired wavelength band. At this time, A controller 140 is required. Further, the light sources can be constituted by respective combinations.

The wavelength converting unit 118 has a characteristic of absorbing light incident on the wavelength converting unit 118 and emitting light of a different wavelength band. The wavelength converting unit 118 may be configured using a quantum dot, which is a nanoparticle material that absorbs the irradiated light and emits light of a different wavelength band.

The wavelength band of the light emitted from the wavelength converter 118 is adjustable through the size of the quantum dot. In addition, the plurality of wavelength conversion units 118 may include nanoparticles of predetermined materials of different sizes.

The image detecting unit 120 detects an image emitted from the sample. The image detector 120 may be implemented as a camera module, and may be implemented as a monochromatic camera module as well as a color camera module, and may include a detector and an image-forming lens.

10 is a diagram schematically showing an example of detecting an image emitted by a light irradiated from a time division light source using a color camera module or a mono camera module.

10 is a configuration suitable for obtaining a white light image and a spectroscopic image. In the time division light source 110, white light and narrow-band light for a spectroscopic image are sequentially generated according to a preset time according to a synchronization signal of a time- The detection unit 120 sequentially detects an image according to the light irradiated according to the time division controller synchronization signal, that is, a white light image and a spectroscopic image.

In contrast, FIG. 5 has a form in which a light transmission filter 122 having a characteristic that does not transmit only excitation light that induces fluorescence of the sample is added in the structure of FIG. 10, and may be suitable for acquiring a white light image and a fluorescence image . As shown in FIG. 11, the light transmission filter 122 has a characteristic of not transmitting light in the excitation light wavelength band. 11 is a diagram showing characteristics of an emission light filter having a transmittance characteristic excluding only an excitation light wavelength band.

In FIG. 5, in the time-divisional light source 110, white light and a narrow-band light having excitation light characteristics for inducing fluorescence are sequentially generated according to a predetermined time according to a synchronization signal of the time division controller and irradiated to the sample.

In the sample, not only the reflected light by the excitation light but also the emitted light whose wavelength characteristics are changed by fluorescence by absorbing the excitation light are simultaneously detected, and only the excitation light excluded through the light transmission filter is detected and imaged by the image detecting unit 120 .

In addition, since the reflected light of the white light irradiated for the white light image passes through the light transmission filter 122 when reaching the image detection unit 120, a part of the reflected light may be lost. However, The distortion of the white light image by the light transmission filter 122 can be neglected. As a result, it is possible to acquire multiple images including a white light image and a fluorescence image by this configuration.

In general, a fluorescence image filter uses a light-transmitting filter having a characteristic (FIG. 12) that transmits only a wavelength band of emitted light of a sample. FIG. 12 is a diagram showing the transmission characteristic of a general emission image light emission filter.

In this case, in the structure for obtaining the white light image and the spectroscopic image at the same time, light of the most wavelength band is removed, so that the light transmission filter having such optical characteristics should be removed. However, since the inside of the endoscope is very narrow, it is difficult to realize the function of removing the light transmission filter.

In the present invention, a fluorescence image is obtained by using a light transmission filter having the transmittance characteristic shown in FIG. Only the excitation light transmitted by the endoscope exists in the inner space of the human body for obtaining the image of the endoscope, and when the excitation light among the reflected light transmitted to the camera module is removed, only the emitted light of the sample is transmitted to the camera module to obtain the fluorescence image .

In addition, spectral characteristic distortion of the reflected light is minimized when acquiring a white light image or a spectroscopic image. That is, since only the excitation light wavelength band is not transmitted, most of the reflected light is transmitted to the camera module.

FIG. 13 shows another embodiment for acquiring a white light image, a spectroscopic image, and a fluorescence image obtained through the present invention. In the time-divisional light source 110, white light, narrow-band light for a spectroscopic image, and narrow-band light corresponding to excitation light for a fluorescence image are generated according to the synchronization signal of the time-divisional controller 140, Through the filter 122 and the image detector 120, images corresponding to the respective irradiation lights can be obtained.

The position of the light transmission filter can be mounted as shown in Figs. 14 and 15. Fig. 14 and 15 are views showing the positions of the emission light filters. In Fig. 14 and Fig. 15, the light transmission filter 122 is disposed in front of or behind the imaging lens, respectively. As described above, the camera module is composed of the detector 120 and the imaging lens, and the light transmission filter 122 should be configured in a position before the reflected light is transmitted to the detector 120.

The image processing unit 130 processes the detected image and the control unit 140 synchronizes the time division light source unit 110 and the image processing unit 130. As shown in FIG. 5, the image processing unit 130 may include a light source and a video processor for imaging light reflected from the sample, similar to the configuration of a general optical imaging apparatus.

In general, since light is incident on the sample at the end of the insertion tube of the endoscope, incident light is transmitted from the external light source to the end of the insertion tube through the light transmission portion. In addition, a camera module is provided at the end of the insertion tube, and the camera module detects light reflected from the sample and converts it into a video signal for imaging, and then the video signal is transmitted to the video processor.

At this time, the camera module is composed of a detector for detecting light and an optical lens for transmitting light to a detector, and a display device for outputting a multi-mode image is connected to a video processor for image processing of the camera module .

The control unit 140 may synchronize the time division light source unit 110 with the image detection unit 120 instead of the image processing unit 130 and may synchronize with the image detection unit 120 and the image processing unit 130. 17 is a diagram showing an example in which the time division light source unit is synchronized with the image detection unit. 17, an example in which the time division light source unit 110 is synchronized with the image detection unit 120 is shown.

2) a camera module and a video processor that can be imaged in accordance with a time synchronization signal; 3) a light source and a video processor And 4) a light transmission filter for selecting the wavelength of light entering the camera module.

In the operation of the present invention, when a signal of T1 is sent from the time division controller, light of a wavelength band corresponding to T1 is generated from the light source, and the light is incident on the sample. The camera module synchronizes with the signal of T1, And outputs the image to the corresponding display.

Then T2 ... Tn, etc., the light source and the video processor can receive the light according to the synchronization signal and obtain the corresponding image. If the synchronization signal is transmitted quickly, it is possible to output multiple images in near real time.

The white light image and the spectral image can be obtained by adjusting the wavelength band generated by the light source. However, in order to obtain a fluorescence image contrasted with the emission light due to fluorescence phenomenon of the sample, a suitable light transmission filter should be located on the path where the reflected light enters the detector so that only the emitted light mixed in the reflected light can be detected by the detector .

At this time, the control unit 140 may change the time interval of the predetermined time during which the time-division light source unit 110, the image processing unit 130, and the image detecting unit 120 are synchronized. 16 is a diagram showing an example of a time synchronization signal of the control unit.

Specifically, the time synchronization signal generated through the time division controller may have a constant synchronization signal, and may be different from each other for adjusting the exposure time for obtaining an image. For example, in order to obtain a fluorescent image, a long exposure time is generally required and it is necessary to generate a time synchronization signal suitable for the appropriate exposure time.

In summary, the present invention relates to an endoscope capable of acquiring multiple images such as a white light image, a fluorescence image, and a spectroscopic image. The present invention relates to an image processing apparatus and an image processing method, which are capable of 1) a light source for generating light having various spectral patterns, 2) a video processor for processing image data from a camera module or a camera module, A time-division controller, and 3) a light transmission filter that can select the wavelength of the reflected light input to the camera module.

Specifically, the controller mounted on the light source must be capable of sequentially generating light having various spectral characteristics with time. In addition, the video processor must receive image data from the camera at the input time and display it after a certain image processing.

In addition, in order to obtain a fluorescent image, a light transmission filter may be mounted on the front end of the camera module or a sensor of the camera module and an intermediate lens to excite the excitation light necessary for exciting the sample. By using this configuration to increase the speed of time division, it is possible to provide two or more images in near real time.

Although the present invention has been described in terms of some preferred embodiments, the scope of the present invention should not be limited thereby but should be modified and improved in accordance with the above-described embodiments.

Claims

A time-division light source unit for irradiating light of predetermined wavelength regions in advance to the sample for a predetermined time;

An image detector for detecting an image emitted from the sample;

An image processing unit for processing the detected image; And

And a controller for synchronizing the time-division light source with at least one of the image processor and the image detector.
The apparatus of claim 1, wherein the time-

A broadband light source having a predetermined wide-band wavelength region; And

And a plurality of wavelength selectors that respectively transmit predetermined narrow-band wavelength regions out of the wide-band wavelength regions,

Wherein the controller selects one or more of the plurality of wavelength selection units for the predetermined time.
The apparatus of claim 1, wherein the time-

And a plurality of narrowband light sources having a predetermined narrowband wavelength region,

Wherein the controller selects one or more of the plurality of narrowband light sources for the predetermined time.
The apparatus of claim 1, wherein the time-

A narrow band light source having a predetermined narrow band wavelength region; And

And a wavelength converter for converting the narrowband wavelength region into another predetermined narrowband wavelength region,

Wherein the control unit selects one or more of the one or more other narrow-band wavelength regions for the predetermined time.
The method of claim 4,

Wherein the wavelength converter includes a layer of a wavelength modulation material formed on a substrate,

Wherein the wavelength modulation material absorbs incident light of a predetermined wavelength band and emits light of a wavelength band different from the incident wavelength band.
The method of claim 5,

Wherein the wavelength modulation material comprises quantum dots that are predetermined nanomaterial particles.
The method of claim 6,

Wherein the size of the nanomaterial particles is selected according to a wavelength region to be changed.
The method of claim 7,

Wherein the plurality of wavelength converters each include the nanomaterial particles of different sizes.
The image processing apparatus according to claim 1,

And a light transmission filter for passing fluorescence of a predetermined wavelength region.
The light-emitting device according to claim 9,

Wherein the excitation light is set to exclude only the excitation light in a predetermined wavelength region for generating the fluorescence.
The method of claim 10,

Wherein the light-

Wherein the imaging optical system is disposed in front of the imaging lens with respect to the traveling direction of the reflected light emitted from the sample.
The method of claim 10,

Wherein the light-

Wherein the imaging optical system is disposed behind the imaging lens with respect to the traveling direction of the reflected light emitted from the sample.
The method according to claim 1,

Wherein the time-divisional light source unit irradiates the white light and the spectral light of a part of the wavelength range of the white light for a preset time.
The method according to claim 1,

Wherein the time-divisional light source unit irradiates the spectral light, which is a part of the wavelength region of the white light, with the excitation light of a predetermined wavelength region for a predetermined time.
The method according to claim 1,

Wherein the time-divisional light source unit irradiates white light and excitation light of a predetermined wavelength region for a predetermined time period.
The method according to claim 1,

Wherein the time-divisional light source unit irradiates the white light, the spectral light that is a part of the wavelength region of the white light, and the excitation light of the predetermined wavelength region for a preset time.
The method according to claim 1,

Wherein the control unit changes the time interval of the preset time.