KR102747043B1 - Endoscope system for multi image - Google Patents

Abstract

A multi-image endoscope system is disclosed. The multi-image endoscope system includes a time-division light source unit, an image detection unit, an image processing unit, and a control unit. The time-division light source unit irradiates light of different preset wavelength ranges onto a sample 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

{ENDOSCOPE SYSTEM FOR MULTI IMAGE}

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

Medical optical imaging devices such as endoscopes are being developed with technologies to improve image resolution and contrast for lesions.

Specifically, in addition to white light imaging technology that shows the surface structure of existing tissues, spectral imaging technology that shows the spectral characteristics of tissues with contrast, and fluorescence imaging technology that shows the fluorescence characteristics of tissues with contrast are being introduced as endoscopic imaging technologies.

In particular, technologies are being developed for imaging with image contrast, such as autofluorescence of human tissues or induced fluorescence resulting from the binding of fluorescent molecules injected through blood vessels to tissues.

Figure 1 is a schematic diagram illustrating the structure of a white light imaging device. Figure 1 illustrates the configuration of a typical white light optical imaging device. In order to obtain a white light image, white light having a broad spectrum is irradiated onto the sample, and the light reflected from the sample is detected and imaged.

Reflection from a sample includes specular reflection from the surface, diffusion, and scattering from the inside. In general, when white light is irradiated, the reflected light is also white light, and a color image can be obtained using a color camera.

In contrast, a spectroscopic imaging device is a device for viewing the reflection characteristics of a sample for narrow-band light. Figures 2 and 3 are schematic diagrams of the structure of a spectroscopic imaging device. Similar to a white light imaging device, it is composed of a light source, a camera for imaging, etc.

FIGS. 2 and 3 illustrate a method of irradiating a narrowband light onto a sample, detecting the reflected light, and imaging it (FIG. 2), and a method of irradiating a broadband light and then transmitting only the narrowband light among the reflected light from the sample to the camera before it reaches the camera, thereby imaging it (FIG. 3). In particular, narrowband light for inspection is sometimes used to obtain image information of a sample by utilizing multiple wavelength bands.

A fluorescence imaging device is a device that detects and images light emitted from fluorescent molecules due to a fluorescence phenomenon present in a sample. Fig. 4 is a drawing schematically illustrating the structure of a fluorescence imaging device. Fig. 4 illustrates the structure of a representative fluorescence imaging device.

To obtain a fluorescence image, excitation light to excite fluorescent molecules and a detector to detect emission light emitted from the fluorescent molecules are required, and these can be implemented in various ways.

First, a sample containing fluorescent molecules is irradiated with light (excitation light) of a wavelength band that can excite the fluorescent molecules. For this purpose, an optical system that can irradiate only narrow-band light, such as a bandpass filter or a monochrometer, can be used.

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

In order to obtain a fluorescence image, the emission light must be detected by a detector and imaged. To this end, an emission filter or monochrometer is inserted into the detector to block light of wavelengths other than the emission light.

In this way, various inventions are being developed for applying white light images, spectroscopic images, and fluorescence images to endoscopic systems for examining internal human tissues by inserting them into the human body.

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

However, although these structures are successful in obtaining individual images, their optical systems are complex in structure and have limitations in providing multiple images quickly.

US 9532719 B2

The present invention has been made to solve the above-described conventional problems, and aims to provide an endoscopic system having a simple optical system structure and capable of quickly providing multiple images.

In order to achieve the above object, the multi-image endoscope 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-division light source unit irradiates light of different preset wavelength ranges onto a sample 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 detection unit and the image processing unit.

According to this configuration, since the light source unit is used in time division by synchronizing with at least one of the image processing unit and the image detection unit, it is not necessary to provide the endoscope system with image processing devices corresponding to different wavelength ranges to obtain multiple images, thereby simplifying the structure of the optical system while allowing multiple images to be provided quickly.

At this time, the time-division light source unit includes a broadband light source having a preset broadband wavelength range, and a plurality of wavelength selection units each transmitting a preset wavelength range among the broadband wavelength range, and the control unit can select at least one of the plurality of wavelength selection units for a preset time. With this configuration, it is possible to provide a time-division light source using a broadband light source.

In addition, the time-division light source unit includes a plurality of narrow-band light sources having a preset narrow-band wavelength range, and the control unit can select one or more of the plurality of narrow-band light sources for a preset time. With this configuration, it is possible to provide a time-division light source using the narrow-band light source.

In addition, the time-division light source unit includes a narrow-band light source having a preset narrow-band wavelength range, and a plurality of wavelength conversion units that convert the narrow-band wavelength range into another preset narrow-band wavelength range, and the control unit can select at least one of the plurality of wavelength conversion units for a preset time.

With this configuration, light of various wavelengths can be generated using only a small number of narrowband light sources, thereby simplifying the structure of the optical system while increasing the light output efficiency.

At this time, the plurality of wavelength conversion units may each include nanoparticles of preset materials of different sizes. With this configuration, by changing the size of the nanomaterial particles, it is possible to easily implement a wavelength conversion unit with high optical output efficiency corresponding to various wavelengths.

In addition, the image detection unit may include a light transmitting filter for passing a preset wavelength range of fluorescence. With this configuration, it is possible to acquire multiple images including a white light image, a spectral image, and a fluorescence image.

At this time, the light transmission filter can be set to exclude a preset wavelength range of the excited light. With this configuration, it is possible to acquire multiple images including fluorescence images without deteriorating the performance of white light images or spectroscopic images.

In addition, the time interval of the preset time at which at least one of the light source unit, the image processing unit, and the image detection unit is synchronized can be changed. With this configuration, by adjusting the time interval according to the wavelength range, it is possible to obtain an optimal image for each wavelength range.

According to the present invention, since the light source and the image processing unit or image detection unit are synchronized and used in a time-division manner, it is not necessary to provide the endoscope system with image processing devices corresponding to different wavelength ranges to obtain multiple images, thereby simplifying the structure of the optical system while allowing multiple images to be provided quickly.

In addition, it is possible to provide a time-division light source by using a broadband light source.

Additionally, it is possible to provide a time-division light source by 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.

In addition, by changing the size of the nanomaterial particles, it is possible to easily implement a wavelength conversion unit with high optical output efficiency corresponding to various wavelengths.

In addition, it is possible to acquire multiple images including white light images, spectroscopic images, and fluorescence images.

Additionally, it is possible to acquire multiple images including fluorescence images without compromising the performance of white light images or spectroscopic images.

Additionally, by adjusting the time interval according to the wavelength range, it is possible to obtain an optimal image for each wavelength range.

Figure 1 is a schematic diagram illustrating the structure of a white light imaging device.
Figures 2 and 3 are schematic drawings illustrating the structure of a spectroscopic imaging device.
Figure 4 is a schematic diagram illustrating the structure of a fluorescent imaging device.
FIG. 5 is a schematic block diagram of a multi-image endoscopy system according to one embodiment of the present invention.
Figures 6 and 7 are schematic diagrams illustrating the structure of a time-division light source using a broadband light source.
Figure 8 is a schematic diagram illustrating the structure of a time-division light source using multiple narrowband light sources.
Figure 9 is a schematic diagram illustrating the structure of a time-division light source using wavelength conversion of a narrowband light source.
FIG. 10 is a schematic diagram illustrating an example of detecting an image emitted by light irradiated from a time-division light source using a color camera module or a mono camera module.
Figure 11 is a drawing showing the characteristics of a light transmission filter having transmittance characteristics excluding only the wavelength band of the light here.
Figure 12 is a drawing showing the transmittance characteristics of a typical emission filter for fluorescence imaging.
FIG. 13 is a diagram illustrating an example for obtaining a white light image, a spectroscopic image, and a fluorescence image using light irradiated using a time-division light source.
Figures 14 and 15 are drawings showing examples of positions of light transmitting filters.
Figure 16 is a diagram illustrating an example of a time synchronization signal of a control unit.
Figure 17 is a diagram illustrating an example in which a time-division light source unit is synchronized with an image detection unit.

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

FIG. 5 is a schematic block diagram of a multi-image endoscope system (100) according to one embodiment of the present invention. In FIG. 5, the multi-image endoscope system (100) includes a time-division light source unit (110), an image detection unit (120), an image processing unit (130), and a control unit (140). In FIG. 5, the time-division light source unit (110), the image detection unit (120), the image processing unit (130), and the control unit (140) are each implemented as a time-division light source, a camera module, a video processor, and a time-division controller, and the image detection unit (120) includes a light transmission filter (122).

The time-division light source unit (110) irradiates light of different preset wavelength ranges to the sample for a preset time. In order to obtain a white light image, a spectroscopic image, or a fluorescence image, light having corresponding spectral characteristics must be irradiated to the sample. For example, a white light image must emit light in the entire visible light wavelength band, a spectroscopic image must emit light in a spectral wavelength band to be observed, and a fluorescence image must be able to generate light in an excitation light wavelength band to excite fluorescent molecules of the sample. The time-division light source unit (110) generates light having these various spectral characteristics.

At this time, the time-division light source unit (110) includes a broadband light source (112) having a preset broadband wavelength range, and a plurality of wavelength selection units (114) that each transmit a preset wavelength range among the broadband wavelength range, and the control unit (140) can select one or more of the plurality of wavelength selection units (114) for a preset time.

Figures 6 and 7 are schematic diagrams illustrating the structure of a time-division light source using a broadband light source. Figures 6 and 7 each illustrate a structure that uses an optical filter (narrow-band transmission filter) or a monochrometer as a wavelength selection unit (114) to generate light of a desired wavelength band from a broadband light source (112). At this time, the wavelength selection unit (114) may have a filter wheel structure equipped with multiple filters to generate multiple wavelengths, and an appropriate filter may be selected through a controller (140).

In addition, the time-division light source unit (110) includes a plurality of narrow-band light sources (116) having a preset narrow-band wavelength range, and the control unit (140) can select one or more of the plurality of narrow-band light sources (116) for a preset time. Fig. 8 is a drawing schematically illustrating the structure of a time-division light source using a plurality of narrow-band light sources. Fig. 8 illustrates a structure that combines a plurality of narrow-band light sources (116) using optical systems such as mirrors and lenses. At this time, various wavelength bands can be created by controlling each light source (116).

In addition, the time-division light source unit (110) includes a narrowband light source (116) having a preset narrowband wavelength range, and a plurality of wavelength conversion units (118) that convert the narrowband wavelength range into another preset narrowband wavelength range, and the control unit (140) can select one or more of the plurality of wavelength conversion units (118) for a preset time.

Fig. 9 is a schematic diagram illustrating the structure of a time-division light source using wavelength conversion of a narrowband light source. In Fig. 9, when a narrowband light source (116) and a wavelength conversion unit (118) are used, the wavelength band of the narrowband light source (116) can be shifted to a desired wavelength band, and at this time, a controller (140) for controlling the wavelength conversion unit (118) is required. In addition, a light source can be configured by each combination.

The wavelength conversion unit (118) has the characteristic of absorbing light incident on the wavelength conversion unit (118) and emitting light of a different wavelength band. The wavelength conversion unit (118) can be configured using quantum dots, which are nano particle materials that absorb irradiated light and emit light of a different wavelength band.

The wavelength band of light emitted from the wavelength conversion unit (118) can be controlled by the size of the quantum dots. In addition, a plurality of wavelength conversion units (118) may each include nanoparticles of preset materials of different sizes.

The image detection unit (120) detects an image emitted from a sample. The image detection unit (120) is implemented as a camera module, and can be implemented as a color camera module as well as a mono camera module, and can be composed of a detector and an imaging lens.

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

FIG. 10 is a configuration suitable for obtaining a white light image and a spectral image, in which narrowband light for white light and spectral images is sequentially generated at a preset time according to a synchronization signal of a time-division controller in a time-division light source (110), and an image detection unit (120) sequentially detects images according to the light irradiated according to the synchronization signal of the time-division controller, that is, a white light image and a spectral image.

In comparison, Fig. 5 has a form in which a light transmitting filter (122) having a characteristic of not transmitting only the excitation light that induces fluorescence of the sample is added to the structure of Fig. 10, and may be suitable for obtaining white light images and fluorescence images. The light transmitting filter (122) has a characteristic of not transmitting light in the wavelength band of the excitation light, as shown in Fig. 11. Fig. 11 is a drawing illustrating the characteristics of an emission filter having a transmittance characteristic that excludes only the wavelength band of the excitation light.

In Fig. 5, in the time-division light source (110), white light and narrowband light with excitation light characteristics for inducing fluorescence of the sample are sequentially generated at a preset time according to the synchronization signal of the time-division controller, and are irradiated onto the sample.

In the sample, not only reflected light due to the excitation light but also emitted light with a changed wavelength characteristic due to fluorescence by absorbing the excitation light is generated simultaneously, and only the excitation light that is excluded through the light transmission filter is detected by the image detection unit (120) and imaged.

In addition, when the reflected light from the sample of white light investigated for the white light image reaches the image detection unit (120), some of the reflected light may be lost because it passes through the light transmission filter (122). However, since only a small portion is lost compared to the entire reflected wavelength band, distortion of the white light image by the light transmission filter (122) can be ignored. As a result, by this configuration, it is possible to obtain a multiple image including a white light image and a fluorescence image.

In general, filters for fluorescence imaging use light transmitting filters that have the characteristic of transmitting only the wavelength band of the emission light of the sample (Fig. 12). Fig. 12 is a diagram illustrating the transmittance characteristics of a general emission light filter for fluorescence imaging.

In this case, since most of the wavelength band light is removed in the structure for obtaining white light images and spectral images at the same time, the light transmission filter with these optical characteristics must be removed. However, since the inside of the endoscope is very narrow, it is difficult to implement the light transmission filter removal function.

In the present invention, a fluorescence image is obtained using a light transmission filter having the transmittance characteristics illustrated in Fig. 11. The internal space of the human body for obtaining an image of an endoscope only contains excitation light transmitted by the endoscope, and if the excitation light is removed from the reflected light transmitted to the camera module, only the emitted light of the sample is transmitted to the camera module, allowing a fluorescence image to be obtained.

In addition, it minimizes the distortion of spectral characteristics of reflected light when acquiring white light images or spectral images. That is, since it does not transmit only the wavelength band of the excitation light, most of the reflected light is transmitted to the camera module.

In addition, Fig. 13 shows another embodiment for obtaining white light images, spectroscopic images, and fluorescence images that can be obtained through the present invention. In a time-division light source (110), white light, narrowband light for spectroscopic images, narrowband light corresponding to excitation light for fluorescence images, etc. are generated and irradiated onto a sample according to a synchronization signal of a time-division controller (140), and images corresponding to each irradiated light can be obtained through a light transmission filter (122) and an image detection unit (120).

The position of the light transmission filter can be mounted as shown in FIG. 14 and FIG. 15. FIG. 14 and FIG. 15 are drawings showing the position of the emission light filter. In FIG. 14 and FIG. 15, the light transmission filter (122) is respectively positioned in front or behind the imaging lens. In this way, the camera module is composed of the detector (120) and the imaging lens, and the light transmission filter (122) must be configured at 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 be configured with a video processor for visualizing light reflected from a light source and a sample, similar to the configuration of a general optical imaging device.

Since light is generally incident on the sample from the tip of the insertion tube of the endoscope, the incident light is transmitted from an external light source to the tip of the insertion tube through a light transmission unit. In addition, there is a camera module at the tip of the insertion tube, and the camera module detects the light reflected from the sample, converts it into a video signal for imaging, and then transmits it to a video processor.

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

In addition, the control unit (140) can synchronize the time-division light source unit (110) with the image detection unit (120) rather than the image processing unit (130), and can also synchronize with both the image detection unit (120) and the image processing unit (130). Fig. 17 is a drawing showing an example of synchronizing the time-division light source unit with the image detection unit. Unlike Fig. 5, Fig. 17 shows an example of synchronizing the time-division light source unit (110) with the image detection unit (120).

In other words, the present invention comprises 1) a light source that generates light of various spectral characteristics and irradiates light by receiving a time synchronization signal, 2) a camera module and a video processor capable of imaging in accordance with the time synchronization signal, 3) a time division controller that outputs a time synchronization signal for controlling the light source and the video processor, and 4) a light transmission filter capable of selecting the wavelength of light entering the camera module.

Looking at the configuration of the present invention from an operational aspect, when a signal of T1 is sent from a time-division controller, light of a wavelength band corresponding to T1 is generated from a light source and incident on a sample, and a camera module synchronizes with the signal of T1 to image the light reflected from the sample and output it to a corresponding display.

Then, if synchronization signals such as T2… Tn are sent continuously, the light source and video processor can input light according to the synchronization signal and obtain the corresponding image. If the synchronization signal is sent quickly, multiple images can be output almost in real time.

White light images and spectroscopic images can be obtained by controlling the wavelength band generated from the light source. However, in order to obtain a fluorescence image with contrast using the emission light due to the fluorescence phenomenon of the sample, an appropriate light transmission filter must be positioned in the path through which the reflected light enters the detector so that only the emission light mixed with the reflected light can be detected by the detector.

At this time, the control unit (140) can change the time interval of the preset time at which the time-division light source unit (110) and the image processing unit (130) or image detection unit (120) are synchronized. Fig. 16 is a diagram illustrating an example of a time synchronization signal of the control unit.

Specifically, the time synchronization signals generated through the time division controller may be constant for each synchronization signal, or may be different for adjusting the exposure time for obtaining an image. For example, in order to obtain a fluorescence image, a long exposure time is generally required, and an appropriate time synchronization signal must be generated for an 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, or a spectral image. The present invention comprises 1) a light source that generates light having various spectral patterns, 2) a time division controller that temporally divides a camera module or a video processor that processes image data from the camera module to enable the multiple images to be output alternately and continuously, and 3) a light transmission filter capable of selecting the wavelength of reflected light input to the camera module.

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

In addition, among the multi-imaging technologies, a light transmission filter capable of excluding excitation light required to excite a sample may be mounted in front of the camera module or between the sensor of the camera module and the objective lens to obtain a fluorescence image. By using this configuration, the speed of temporal division is increased, making it possible to provide two or more multi-images in almost real time.

Although the present invention has been described by some preferred embodiments, the scope of the present invention should not be limited thereby, but should extend to modifications and improvements of the above embodiments as supported by the scope of the claims.

100: Multi-Image Endoscopy System
110: Time-division light source
112: Broadband light source
114: Wavelength selector
116: Narrowband light source
118: Wavelength converter
120: Image detection unit
122: Light Transmitting Filter
130: Image processing unit
140: Control Unit

Claims (17)

A time-division light source unit that irradiates light of different preset wavelength ranges onto a sample for a preset period of time;
An image detection unit for detecting an image emitted from the sample;
An image processing unit for processing the detected image; and
A multi-image endoscope system including a control unit that synchronizes the time-division light source unit with at least one of the image processing unit and the image detection unit,
The above image detection unit,
Including a light transmitting filter for passing fluorescence of a preset wavelength range,
It is set to exclude only the excitation light of a preset wavelength range to generate the above fluorescence,
The above time-division light source unit irradiates a plurality of lights selected from among white light, a spectrum that is a portion of the wavelength range of the white light, and excitation light of a preset wavelength range for a preset time, respectively.
The above time-division light source unit is,
A narrowband light source having a preset narrowband wavelength range; and
It comprises a plurality of wavelength converters for converting the above narrowband wavelength range into another preset narrowband wavelength range,
The above control unit selects one or more of the plurality of wavelength converters for the preset time,
The above time-division light source unit irradiates white light, a spectrum which is a portion of the wavelength range of the white light, and excitation light of a preset wavelength range for a preset time, respectively.
A multi-image endoscope system, characterized in that the control unit changes the time interval of the preset time according to the exposure time set corresponding to the wavelength range of light irradiated by the time-division light source unit.
delete delete delete In claim 1,
The wavelength conversion unit includes a layer of wavelength modulation material formed on a substrate,
A multi-image endoscope system, wherein the wavelength modulation material absorbs light of a preset wavelength band that is incident and emits light of a different wavelength band from the incident wavelength band.
In claim 5,
A multi-image endoscope system, wherein the wavelength modulation material comprises quantum dots, which are preset nano-material particles.
In claim 6,
A multi-image endoscope system, characterized in that the size of the nanomaterial particles is selected according to the wavelength range to be changed.
In claim 7,
A multi-image endoscope system, wherein each of the plurality of wavelength converters comprises nanomaterial particles of different sizes.
delete delete In claim 1,
The above light transmitting filter,
A multi-image endoscope system characterized in that the imaging lens is positioned in front of the imaging lens with respect to the direction of propagation of reflected light emitted from the sample.
In claim 1,
The above light transmitting filter,
A multi-image endoscope system characterized in that the imaging lens is positioned behind the direction of propagation of reflected light emitted from the sample.
delete delete delete delete delete

Images