A short-wave infrared fluorescence endoscopy device and method

Abstract

This invention discloses a short-wave infrared fluorescence endoscopic imaging device and method. Based on a pre-made near-infrared endoscope, the device achieves dual-path multiplexing of the original imaging and illumination channels. Specifically, the imaging channel performs white light imaging and excitation light scanning, while the illumination channel performs white light illumination and short-wave infrared fluorescence collection. The excitation light source module is connected to the scanning module, and the scanning and white light imaging modules are connected to the endoscope via a dichroic mirror. The short-wave infrared detection module and white light illumination module are connected to the endoscope via a multi-integrated fiber bundle. The control and data acquisition module is electrically connected to the scanning module, short-wave infrared detection module, and white light imaging module, respectively. This invention eliminates the need to modify the endoscope's structure, overcomes the technical bottleneck of pre-made endoscopes being unable to perform short-wave infrared fluorescence imaging, and achieves deep fusion of white light and short-wave infrared fluorescence dual-modal imaging. This effectively reduces scattering and autofluorescence interference, and improves the tissue penetration depth and signal-to-background ratio of endoscopic imaging.

Description

Technical Field

[0001] This invention relates to the field of biofluorescence endoscopy technology, specifically to a short-wave infrared fluorescence endoscopy imaging device and method. Background Technology

[0002] Medical endoscopes are medical devices that are inserted through natural cavities or small incisions in the human body to obtain real-time images of internal tissues and organs for disease diagnosis, surgical guidance, and minimally invasive treatment. Traditional endoscopes use white light illumination for color imaging, which makes it difficult to detect the fine structure, function, and lesions of tissues. Its main limitations are: (1) White light imaging relies on differences in hemoglobin absorption, resulting in insufficient contrast for non-vascular lesions (such as early adenomas); (2) Visible light has low penetration depth in blood and biological tissues, making it impossible to show tumor infiltration in the submucosal layer; (3) It lacks molecular recognition function, making it difficult to distinguish the metabolic differences between inflammatory and cancerous tissues. White light endoscopes urgently need to be supplemented by multimodal imaging technology in scenarios such as tumor boundary delineation and micrometastasis detection.

[0003] Near-infrared fluorescence endoscopy uses near-infrared light to excite fluorescent agents (such as indocyanine green) for labeling, thereby acquiring information on the deep structure, blood flow, and lesions of tissues and organs in the body, and realizing functions such as angiography, tumor resection, and lymphatic tracing. Existing near-infrared fluorescence endoscopes support operation in the visible and near-infrared I region (400-900nm) bands: (1) the scattering coefficient of biological tissues in the near-infrared I region (NIR-I) band is still relatively high; (2) the autofluorescence background (such as elastin and collagen) in biological tissues produces strong interference in the NIR-I band. Therefore, existing near-infrared fluorescence endoscopy still has the problems of high background interference, limited imaging contrast and depth, and limitations in imaging deep microstructures.

[0004] Biological tissues exhibit a lower scattering coefficient in the near-infrared II (NIR-II) band (900nm-1700nm), also known as the short-wave infrared band. Short-wave infrared fluorescence imaging enables deeper tissue penetration, higher contrast, and lower background fluorescence interference, significantly improving image quality and diagnostic accuracy, making it more suitable for deep vascular imaging and tumor boundary delineation. However, the imaging channels of most existing endoscopes are composed of high-refractive-index glass lenses (such as BK7 or SF-type glass) coated with antireflective films in the 400-900nm band, resulting in extremely low transmittance of short-wave infrared light. Furthermore, directly using miniaturized image sensors for short-wave infrared fluorescence imaging is not feasible: miniaturized image sensors use silicon materials, which do not respond to short-wave infrared photons; while InGaAs (indium gallium arsenide) detectors respond up to 1700nm, they suffer from high noise (requiring deep cooling for suppression), large pixel size, limited pixel count, difficulty in miniaturizing to fit endoscope size, and high cost. These systemic technical obstacles prevent existing endoscopes from supporting short-wave infrared fluorescence imaging. Therefore, it is necessary to study shortwave infrared fluorescence endoscopic imaging devices and methods. Summary of the Invention

[0005] The purpose of this invention is to address the problem that existing endoscopic imaging channels cannot directly perform short-wave infrared fluorescence imaging, and to provide a short-wave infrared fluorescence endoscopic imaging device and method. This invention is used for short-wave infrared fluorescence imaging.

[0006] The objective of this invention is achieved through the following technical solution: A first aspect of this invention provides a short-wave infrared fluorescence endoscopic imaging device, comprising: an excitation light source module, a scanning module, an endoscope, a multi-functional fiber optic bundle, a short-wave infrared detection module, a white light illumination module, a white light imaging module, a control and data acquisition module, and a dichroic mirror. The endoscope includes an imaging channel and an illumination channel. The imaging channel has an eyepiece port and an objective lens port at both ends. The illumination channel has an illumination channel inlet and an illumination channel outlet at both ends. The excitation light source module is optically connected to the scanning module. The scanning module and the white light imaging module are optically connected to the eyepiece port via the dichroic mirror. The short-wave infrared detection module and the white light illumination module are optically connected to the illumination channel inlet via the multi-functional fiber optic bundle. The control and data acquisition module is electrically connected to the scanning module, the short-wave infrared detection module, and the white light imaging module, respectively.

[0007] The excitation light source module generates a laser beam of a preset wavelength and sends it to the scanning module. The scanning module modulates the laser beam into a beam with a specified scanning frequency and scanning path, couples it to the eyepiece port via a dichroic mirror, enters the imaging channel, and exits from the objective lens port to the sample. The fluorescence signal generated by the sample is emitted to the short-wave infrared detection module after passing through the illumination channel and the multi-in-one fiber bundle. The short-wave infrared detection module converts the received fluorescence signal into an electrical signal. The white light illumination module provides illumination white light for the white light imaging mode. The illumination white light enters the illumination channel after passing through the multi-in-one fiber bundle and the illumination channel entrance, and exits from the illumination channel exit to the sample. The visible light signal reflected by the sample passes through the imaging channel and the dichroic mirror to reach the white light imaging module, which generates a white light image. The control and data acquisition module is used to provide the scanning frequency and scanning path, acquire the white light image, and perform pixel mapping processing on the acquired electrical signal to obtain the fluorescence image, so as to realize the real-time synchronous display of the white light image and the fluorescence image.

[0008] Furthermore, the excitation light source module includes a laser, which generates a laser beam with a wavelength of 650nm-1064nm;

[0009] The laser is a space laser, a fiber laser, or an LED.

[0010] Furthermore, the scanning module includes a MEMS scanning micromirror and a beam shaping lens group. The laser beam generated by the laser is incident on the surface of the MEMS scanning micromirror, and after being compressed by the dichroic mirror and the beam shaping lens group, it is coupled to the eyepiece port.

[0011] Furthermore, the bundled end of the multi-in-one fiber bundle is connected to the entrance optical path of the illumination channel, one of the split ends of the multi-in-one fiber bundle is connected to the optical path of the white light illumination module, and the remaining split ends of the multi-in-one fiber bundle are connected to the optical path of the short-wave infrared detection module.

[0012] The white light illumination module includes a white light source, which is connected to one of the beam splitters of the multi-in-one fiber optic bundle.

[0013] Furthermore, the shortwave infrared detection module includes a filter and a photodetector connected in sequence. The filter is connected to the optical path of the split end of the multi-in-one fiber bundle, and the photodetector is electrically connected to the control and data acquisition module.

[0014] Furthermore, the filter is a short-wave infrared long-pass filter;

[0015] The photodetectors include indium gallium arsenide avalanche photodiode detectors, photomultiplier tubes, and superconducting nanowire single-photon detectors.

[0016] Furthermore, the white light imaging module includes an imaging lens group and a camera. The visible light signal reflected by the sample is collected at the eyepiece port after passing through the imaging channel. After being reflected and split by the dichroic mirror, the light is imaged on the camera by the imaging lens group.

[0017] Furthermore, the control and data acquisition module includes a data acquisition card, a host computer, and a MEMS controller. The data acquisition card is connected to a photodetector. The data acquisition card, the MEMS controller, and the camera are all connected to the host computer. The MEMS controller is connected to a MEMS scanning micromirror.

[0018] The host computer synchronously controls the scanning frequency of the MEMS scanning micromirror and the sampling frequency of the data acquisition card. The data acquisition card collects electrical signals from the photodetector and sends them to the host computer, which performs pixel-mapping processing of the fluorescence intensity data to obtain a fluorescence image. The camera sends the white light image it generates to the host computer, which then displays the white light image and the fluorescence image synchronously in real time.

[0019] Furthermore, the sampling frequency of the data acquisition card is an integer multiple of the scanning frequency of the MEMS scanning micromirror.

[0020] A second aspect of this invention provides an imaging method based on the aforementioned shortwave infrared fluorescence endoscopic imaging device, comprising the following steps:

[0021] Step S1: The white light illumination module is connected to the entrance of the illumination channel through an all-in-one fiber bundle to illuminate the sample. The visible light signal reflected by the sample passes through the imaging channel, beam shaping lens group, dichroic mirror beam splitting and reflection, and imaging lens group to form an image on the target surface of the camera. The white light image is then acquired and displayed in real time by the host computer.

[0022] Step S2: The host computer sends a command to control the scanning path of the MEMS scanning micromirror and sends the command to the data acquisition card to synchronously control the scanning frequency of the MEMS scanning micromirror and the sampling frequency of the data acquisition card, so as to realize the real-time matching of fluorescence signal and scanning coordinates.

[0023] Step S3: The laser beam emitted by the excitation light source module is modulated by the MEMS scanning micromirror, then condensed by the dichroic mirror and beam shaping lens group and coupled to the eyepiece port. The beam is transmitted to the sample through the imaging channel, and the fluorescence signal generated by the sample is transmitted to the entrance of the illumination channel through the illumination channel. It is then emitted to the short-wave infrared detection module through the multi-in-one fiber bundle. After being filtered by the filter, the light is collected by the photodetector and converted into an electrical signal.

[0024] Step S4: The electrical signal is collected by the data acquisition card at a specified frequency and transmitted to the host computer. The host computer performs pixel mapping processing of the fluorescence intensity data in real time to obtain the fluorescence image and realize the real-time synchronous display of the white light image and the fluorescence image.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] (1) The present invention realizes dual optical path multiplexing of the original imaging channel and illumination channel of the endoscope, that is, the imaging channel performs white light imaging and near-infrared excitation light scanning, and the illumination channel performs white light illumination and short-wave infrared fluorescence collection. There is no need to modify the endoscope body structure, which solves the technical bottleneck of rigid endoscope integrated short-wave infrared fluorescence imaging, realizes dual-modal imaging deep fusion, effectively reduces scattering and autofluorescence interference, and improves the tissue penetration depth and signal-to-background ratio of endoscope imaging.

[0027] (2) The present invention is based on the optical system modification of commercially available finished endoscopes. No adjustment is required to the mechanical structure or packaging process of the original probe. The clinical safety certification qualification of the probe is retained, avoiding the complicated process of re-registration of medical devices. The device described in the present invention can be directly and seamlessly connected with existing endoscope equipment without the need for medical staff to retrain or change their operating habits. It is especially suitable for scenarios with extremely high timeliness requirements, such as emergency and minimally invasive surgery.

[0028] (3) The present invention uses an innovative optical system with an ultra-compact design to control the volume of the modified module to less than 1 / 3 of that of traditional endoscope accessories, avoiding interference with the surgical field of vision or increasing the risk of patient trauma due to bulky external equipment. Attached Figure Description

[0029] Figure 1 This is a block diagram of the shortwave infrared fluorescence endoscopic imaging device of the present invention;

[0030] Figure 2 This is a schematic diagram of the structure of the shortwave infrared fluorescence endoscopic imaging device of the present invention;

[0031] Figure 3 These are images showing the white light imaging and near-infrared II region imaging results of the imaging device described in this invention on an ICG sample.

[0032] In the figure, excitation light source module 1 and laser 101 are shown.

[0033] Scanning module 2, MEMS scanning micromirror 201, beam shaping lens group 202;

[0034] Endoscope 3, eyepiece port 301, illumination channel inlet 302, illumination channel outlet 303, objective lens port 304;

[0035] All-in-one fiber bundle 4;

[0036] Shortwave infrared detection module 5, filter 501, photodetector 502;

[0037] White light illumination module 6, white light source 601;

[0038] White light imaging module 7, imaging lens group 701, camera 702;

[0039] Control and data acquisition module 8, data acquisition card 801, host computer 802, MEMS controller 803;

[0040] Dichroic mirror 9. Detailed Implementation

[0041] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. In the following description, when referring to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. It is obvious that the drawings used in the following description are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatuses and methods consistent with some aspects of the invention as detailed in the appended claims.

[0042] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular forms “a,” “the,” and “the” used in this invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0043] It should be understood that although the terms first, second, third, etc., may be used in this invention to describe various information, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, first information may also be referred to as second information without departing from the scope of this invention, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to a determination."

[0044] The present invention will now be described in detail with reference to the accompanying drawings. Unless otherwise specified, the features of the following embodiments and implementations can be combined with each other.

[0045] See Figure 1 and Figure 2The short-wave infrared fluorescence endoscopic imaging device of the present invention includes an excitation light source module 1, a scanning module 2, an endoscope 3, an all-in-one fiber bundle 4, a short-wave infrared detection module 5, a white light illumination module 6, a white light imaging module 7, a control and data acquisition module 8, and a dichroic mirror 9. The endoscope 3 includes an imaging channel and an illumination channel. The imaging channel has an eyepiece port 301 and an objective lens port 304 at both ends, and the illumination channel has an illumination channel inlet 302 and an illumination channel outlet 303 at both ends. Specifically, the endoscope 3 includes an imaging channel composed of a lens group and an illumination channel composed of a fiber bundle or other optical waveguides. The imaging channel of the endoscope 3 is composed of a lens group coated with a visible-near-infrared I-band antireflection film; that is, the channel from the eyepiece port 301 to the objective lens port 304 forms the imaging channel. The illumination channel of the endoscope 3 is composed of an uncoated fiber bundle or optical waveguide; that is, the channel from the illumination channel inlet 302 to the illumination channel outlet 303 forms the illumination channel. The excitation light source module 1 is optically connected to the scanning module 2. The scanning module 2 and the white light imaging module 7 are optically connected to the eyepiece port 301 of the endoscope 3 through the dichroic mirror 9. The short-wave infrared detection module 5 and the white light illumination module 6 are optically connected to the illumination channel entrance 302 of the endoscope 3 through the multi-in-one fiber bundle 4. The control and data acquisition module 8 is electrically connected to the scanning module 2, the short-wave infrared detection module 5, and the white light imaging module 7, respectively.

[0046] In this imaging device, the excitation light source module 1 generates a laser beam of a preset wavelength. The scanning module 2 modulates the laser beam to a beam with a specified scanning frequency and scanning path and couples it to the eyepiece port 301 of the endoscope 3. The scanning module 2 uses an optical modulator (such as a MEMS scanning micromirror 201) to rapidly modulate the beam at the eyepiece port 301 of the imaging channel of the endoscope 3, so that the light spots formed on the sample surface can be rapidly scanned point by point along a specified path. The endoscope 3 transmits the illumination white light emitted from the white light illumination module 6 and the beam emitted from the scanning module 2 to the sample, and receives the visible light and fluorescence signals reflected by the sample. The imaging channel transmits the beam emitted from the scanning module 2 to the sample and transmits the visible light signal reflected by the sample to the white light imaging module 7. The illumination channel transmits the illumination white light emitted from the white light illumination module 6 to the sample and transmits the fluorescence signal generated by the sample to the short-wave infrared detection module 5. The short-wave infrared detection module 5 receives the fluorescence signal generated by the sample and converts the fluorescence signal into an electrical signal. The white light illumination module 6 provides white light for the white light imaging mode. The white light imaging module 7 receives the visible light signal reflected from the sample and generates a white light image of the sample. The control and data acquisition module 8 provides the scanning frequency and scanning path required by the scanning module 2, acquires the white light image from the white light imaging module 7, and acquires the electrical signal from the short-wave infrared detection module 5 for pixelation mapping to obtain the fluorescence image, achieving real-time synchronous display of the white light image and the fluorescence image.

[0047] Specifically, such as Figure 1 and Figure 2 As shown, the excitation light source module 1 generates a laser beam of a preset wavelength to the scanning module 2; the scanning module 2 modulates the laser beam into a beam with a specified scanning frequency and scanning path and couples it to the eyepiece port 301 of the endoscope 3 via the dichroic mirror 9. The beam enters the imaging channel of the endoscope 3 through the eyepiece port 301 and exits from the objective lens port 304 of the endoscope 3 to the sample. The fluorescence signal generated by the sample is collected by the illumination channel of the endoscope 2 to the combining end of the multi-fiber bundle 4, and then emitted from the split end of the multi-fiber bundle 4 to the short-wave infrared detection module 5; the short-wave infrared detection module 5 receives the fluorescence signals from each excitation point along the scanning path and converts them into electrical signals; the white light illumination module 6 provides illumination white light for the white light imaging mode, providing a light source for the white light imaging of the sample, and... The white light illumination module 6 is connected to the illumination channel inlet 302 of the endoscope 3 via the multi-in-one fiber bundle 4. The white light enters the illumination channel of the endoscope 3 through the illumination channel inlet 302 and exits from the illumination channel outlet 303 of the endoscope 3 to the sample. The sample illuminated by the white light reflects visible light signals. The visible light signals reflected by the sample pass through the imaging channel of the endoscope 3 and the dichroic mirror 9 before reaching the white light imaging module 7, which generates a white light image. The control and data acquisition module 8 is used to provide the scanning frequency and scanning path for the scanning module 2, acquires white light images from the white light imaging module 7, and acquires electrical signals from the short-wave infrared detection module 5 for pixel mapping processing to obtain fluorescence images, so as to realize the real-time synchronous display of white light images and fluorescence images.

[0048] Furthermore, the excitation light source module 1 includes a laser 101 for generating a laser beam of a preset wavelength, which is 650nm-1064nm. The laser 101 can be a spatial laser, a fiber laser, or an LED, etc.

[0049] As a preferred embodiment, laser 101 is a combination of a single-mode fiber laser and a fiber collimator. The single-mode fiber laser has a center wavelength of 808 nm and an adjustable output power of 0-75 mW. The fiber collimator has a focal length of f = 15 mm and an output beam diameter of 2 mm. The single-mode fiber laser emits 808 nm excitation light, which is collimated by the fiber collimator to output a 2 mm diameter collimated beam, which is then incident on the scanning module 2.

[0050] Furthermore, the scanning module 2 includes a MEMS (Micro-Electro-Mechanical Systems) scanning micromirror 201 and a beam-shaping lens group 202 connected in sequence. The laser beam generated by the excitation light source module 1 is incident on the surface of the MEMS scanning micromirror 201, and is compressed and coupled to the eyepiece port 301 of the endoscope 3 via the dichroic mirror 9 and the beam-shaping lens group 202. Figure 2As shown. Among them, the beam-shaping lens group 202 has a beam reduction factor of 0.1X-0.5X.

[0051] As a preferred embodiment, the MEMS scanning micromirror 201 is a dual-axis electrostatically driven type with a maximum deflection angle of ±2.5° and a mirror surface size of 3.0×3.0mm². The beam-shaping lens group 202 includes a first lens and a second lens, both of which are plano-convex lenses. The focal length of the first lens is f=60mm, and the focal length of the second lens is f=12mm. The first and second lenses can form a beam-shaping lens group 202 with a magnification of 0.2. The MEMS scanning micromirror 201 receives a drive signal and begins dual-axis deflection. The collimated beam is reflected by the MEMS scanning micromirror 201 to form a dynamic scanning spot. The distance between the first and second lenses is 72mm. The dynamic scanning spot is reduced to 0.5mm by the first and second lenses and coupled to the eyepiece port 301 of the endoscope 3.

[0052] Furthermore, such as Figure 2 As shown, the endoscope 3 includes an imaging channel and an illumination channel. The imaging channel is used to transmit a dynamic scanning light spot with a wavelength of 808nm to the sample surface and to transmit visible light signals with wavelengths of 400nm-700nm reflected by the sample to the white light imaging module 7. The illumination channel is used to transmit illumination white light to the sample surface and to transmit fluorescence signals with wavelengths of 1000-1700nm generated by the sample to the short-wave infrared detection module 5.

[0053] Furthermore, the combined end of the multi-in-one fiber bundle 4 is connected to the illumination channel inlet 302 of the endoscope 3, and the split ends of the multi-in-one fiber bundle 4 are connected to the short-wave infrared detection module 5 and the white light illumination module 6, respectively, for transmitting illumination white light to the endoscope 3 and the sample, and receiving the fluorescence signals generated and reflected by the sample. The operating wavelength of the multi-in-one fiber bundle 4 is 200nm-2400nm.

[0054] Preferably, the multi-in-one fiber bundle 4 is at least a 2-channel bundled fiber bundle; the short-wave infrared detection module 5 is at least one group, and can be expanded to multiple groups according to actual needs. For example, when the multi-in-one fiber bundle 4 is a 2-channel bundled fiber bundle, its bundled end is connected to the illumination channel inlet 302 of the endoscope 3, and the two split ends are respectively connected to the short-wave infrared detection module 5 and the white light illumination module 6. When the multi-in-one fiber bundle 4 is a 4-channel bundled fiber bundle, its bundled end is connected to the illumination channel inlet 302 of the endoscope 3, one split end is connected to the white light illumination module 6, and the other three split ends are respectively connected to three groups of short-wave infrared detection modules 5. Therefore, the split ends of the multi-in-one fiber bundle 4 can connect to multiple short-wave infrared detection modules 5; wherein, the number of channels of the multi-in-one fiber bundle 4 is equal to the number of groups of short-wave infrared detection modules 5 plus 1.

[0055] Furthermore, the short-wave infrared detection module 5 includes a filter 501 and a photodetector 502 connected in sequence. The filter 501 is connected to the splitter end of the multi-in-one fiber bundle 4, and the photodetector 502 is connected to the control and data acquisition module 8. The splitter end of the multi-in-one fiber bundle 4 emits the fluorescence signal generated by the stimulated sample, which is then collected by the photodetector 502 and converted into an electrical signal through the filter 501.

[0056] Furthermore, the filter 501 is a short-wave infrared long-pass filter; the photodetector 502 operates in a wavelength band greater than or equal to 800nm; the photodetector 502 includes, but is not limited to: indium gallium arsenide avalanche photodiode detector, photomultiplier tube, superconducting nanowire single-photon detector, etc.

[0057] As a preferred embodiment, the shortwave infrared detection module 5 includes, in sequence, a filter 501, a photodetector 502, and a current amplifier. The filter 501 is a 1000nm shortwave infrared long-pass filter with a cutoff depth of OD5. The photodetector 502 is a cooled indium gallium arsenide avalanche photodetector (APD) with a response band of 800-1700nm and a bandwidth of 4MHz. The current amplifier can be a transimpedance amplifier with a gain of 10. 3 The wavelength is V / A, and its bandwidth is 1MHz. The dynamic scanning spot coupled to the eyepiece port 301 of the endoscope 3 illuminates the biological sample through the imaging channel of the endoscope 3, exciting a fluorescence signal. The fluorescence signal is collected by the illumination channel of the endoscope 3 to the illumination channel entrance 302. The bundle-combining end of the multi-fiber bundle 4 is connected to the illumination channel entrance 302 of the endoscope 3. The fluorescence signal is propagated through the multi-fiber bundle 4 to one of the bundle-splitting ends, and then filtered by the filter 501 to obtain a fluorescence signal greater than 1000nm, which is transmitted to the photodetector 502. The current amplifier is electrically connected to the photodetector to convert the APD output current into a 0-5V voltage signal.

[0058] Furthermore, the white light illumination module 6 includes a white light source 601, which is connected to one of the split ends of the multi-in-one fiber bundle 4. The white light emitted by the white light source 601 enters the illumination channel of the endoscope 3 through the multi-in-one fiber bundle 4 and the illumination channel entrance 302 of the endoscope 3, and illuminates the sample.

[0059] As a preferred embodiment, the white light illumination module 6 includes a white light source 601, which uses an LED with a color temperature of 5700K and an adjustable output power of 0-100W. One of the split ends of the multi-in-one fiber bundle 4 is connected to the white light source 601, and the white light emitted by the white light source 601 is transmitted to the sample surface through the illumination channel of the multi-in-one fiber bundle 4 and the endoscope 3.

[0060] Furthermore, the white light imaging module 7 includes an imaging lens group 701 and a camera 702. The visible light signal reflected from the sample after being illuminated by white light is collected by the imaging channel of the endoscope 3 to the eyepiece port 301. After being reflected and split by the dichroic mirror 9, it is imaged onto the camera 702 by the imaging lens group 701. The dichroic mirror 9 serves to: change the direction of the illuminating white light; and prevent the reflected high-power infrared light from interfering with the white light imaging. The dichroic mirror 9 has a reflectivity greater than 90% in the 400-700nm wavelength range. The magnification of the imaging lens group 701 is 0.5X-2X.

[0061] As a preferred embodiment, the white light imaging module 7 includes an imaging lens group 701 and a camera 702. The imaging lens group 701 contains only a third lens, which is a plano-convex lens with a focal length f=60mm. The dichroic mirror 9 has a dielectric coating, a 650nm long-wavelength pass, and is installed at a 45° angle. The visible light signal reflected from the sample is transmitted to the eyepiece port 301 via the imaging channel of the endoscope 3, passes sequentially through the second lens and the first lens, and is reflected by the dichroic mirror 9 to the third lens. The third lens images the reflected light onto the camera target surface.

[0062] Furthermore, the control and data acquisition module 8 includes a synchronously connected data acquisition card 801, a host computer 802, and a MEMS controller 803. The data acquisition card 801 is connected to the photodetector 502. The data acquisition card 801, the MEMS controller 803, and the camera 702 are all connected to the host computer 802. The MEMS controller 803 is connected to the MEMS scanning micromirror 201. The host computer 802 synchronously controls the scanning frequency of the MEMS scanning micromirror 201 and the sampling frequency of the data acquisition card 801 to achieve real-time matching of fluorescence signals and scanning coordinates. The data acquisition card 801 acquires the electrical signals (i.e., the voltage signals of the current amplifier) ​​converted from the photodetector 502 and sends them to the host computer 802. The host computer 802 performs pixel-mapping processing of the fluorescence intensity data to obtain a fluorescence image. The camera 702 sends the white light image generated by its imaging to the host computer 802, which then realizes real-time synchronous display of the white light image and the fluorescence image.

[0063] Furthermore, the sampling frequency of the data acquisition card 801 is an integer multiple of the scanning frequency of the MEMS scanning micromirror 201.

[0064] As a preferred embodiment, the control and data acquisition module 8 includes a data acquisition card 801, a host computer 802, and a MEMS controller 803, responsible for driving scanning, synchronous data acquisition, real-time processing, and image generation. The host computer 802 reads the configuration file and sets the scanning parameters. The MEMS controller 803 generates drive and trigger signals, which are sent to the MEMS scanning micromirror 201 and the data acquisition card 801 respectively. The current signal output by the photodetector 502 is converted into a 0-10V voltage signal by a current amplifier. The data acquisition card 801 samples at a rate corresponding to the scanning frequency on the rising edge of the trigger pulse. The data acquisition card 801 transmits the raw voltage data to the host computer 802. The host computer 802 performs pixel-mapping processing on the fluorescence intensity of each sampling point according to the trigger and drive signal parameters to generate a fluorescence image.

[0065] It is worth mentioning that the present invention also provides an imaging method based on the short-wave infrared fluorescence endoscopic imaging device of the above embodiments.

[0066] like Figure 2 As shown, the imaging method specifically includes the following steps:

[0067] In step S1, the white light illumination module 6 is connected to the illumination channel entrance 302 of the endoscope 3 through the multi-in-one fiber bundle 4 to illuminate the sample. The visible light signal reflected by the sample is imaged on the target surface of the camera 702 through the imaging channel of the endoscope 3, the beam shaping lens group 202, the dichroic mirror 9, and the imaging lens group 701. The white light image is then collected and displayed in real time by the host computer 802.

[0068] In step S2, the host computer 802 issues a command to control the scanning path of the MEMS scanning micromirror 201, and at the same time sends the command to the data acquisition card 801 to synchronously control the scanning frequency of the MEMS scanning micromirror 201 and the sampling frequency of the data acquisition card 801, so as to realize the real-time matching of fluorescence signal and scanning coordinate.

[0069] In step S3, the laser beam emitted by the excitation light source module 1 is modulated by the MEMS scanning micromirror 201, then narrowed by the dichroic mirror 9 and the beam shaping lens group 202 and coupled to the eyepiece port 301 of the imaging channel of the endoscope 3. The beam is then transmitted to the sample through the imaging channel of the endoscope 3, and the fluorescence signal generated by the sample is transmitted to the illumination channel entrance 302 through the illumination channel of the endoscope 3. After passing through the multi-in-one fiber bundle 4, the beam is emitted to the short-wave infrared detection module 5, filtered by the filter 501, collected by the photodetector 502, and converted into an electrical signal. The MEMS scanning micromirror 201 enables the scanning of the excitation spot on the sample.

[0070] Step S4: The electrical signal is collected by the data acquisition card 801 at a specified frequency and transmitted to the host computer 802. The host computer 802 performs pixel mapping processing of the fluorescence intensity data in real time to obtain the fluorescence image and realize the real-time synchronous display of the white light image and the fluorescence image.

[0071] The imaging method of the present invention will be described in detail below with reference to a specific embodiment, so that the purpose and effect of the present invention will become more apparent. The imaging method specifically includes the following steps:

[0072] S1, White Light Imaging Mode:

[0073] ① Start the white light source 601. One of the split ends of the multi-in-one fiber bundle 4 is connected to the white light source 601. The combined end of the multi-in-one fiber bundle 4 is connected to the illumination channel entrance 302 of the endoscope 3. The illumination white light (with a wavelength of 400-700nm) is transmitted to the illumination channel of the endoscope 3 through the multi-in-one fiber bundle 4, and evenly illuminates the sample surface.

[0074] ② The visible light signal reflected by the sample is transmitted to the eyepiece port 301 through the imaging channel of the endoscope 3, and then reflected and split by the dichroic mirror 9 to the imaging lens group 701 after passing through the beam shaping lens group 202.

[0075] ③ The reflected light is imaged onto the target surface of the camera 702 by the imaging lens group 701, and the host computer 802 controls the acquisition and real-time display of a white light image with a resolution of 1280×1024 (frame rate 30fps).

[0076] S2, Scan Synchronization Control:

[0077] ① The laser 101 with a wavelength of 808nm is activated, and the generated laser beam is output as a collimated beam with a diameter of 2mm through an optical fiber collimator and incident on the surface of the MEMS scanning micromirror 201 at an incident angle of 22.5°.

[0078] ②The host computer 802 reads the configuration file and sets the scanning parameters: x-axis resonant scanning, which is a sine wave with a frequency of 1000Hz, and y-axis quasi-static scanning, which is a sawtooth wave with a frequency of 100Hz, forming a spiral light spot trajectory.

[0079] ③ Drive signal generation: The MEMS controller 803 outputs a 2kHz sine wave on the x-axis and a 100Hz stepped sawtooth wave digital signal on the y-axis to drive the comb electrodes on the x-axis and y-axis.

[0080] ④ Trigger pulse generation: The MEMS controller 803 monitors the zero-crossing point of the x-axis sine wave (once every 1ms) and generates a 1kHz TTL pulse (3.3V, 10ns pulse width) as the sampling clock for the data acquisition card 801.

[0081] ⑤ Phase Locking: After each y-axis scan (10ms), the FPGA sends a frame synchronization signal to the acquisition card to start the processing of a new frame image.

[0082] ⑥ The collimated beam is reflected by the MEMS scanning micromirror 201 to form a dynamic scanning spot. The beam is then reduced to 0.5mm by the first and second lenses in the beam shaping lens group 202 and coupled to the eyepiece port 301 of the endoscope 3. The beam is then irradiated onto the biological sample through the imaging channel of the endoscope 3, exciting a fluorescence signal. The fluorescence signal is collected at the light cone through the illumination channel of the endoscope 3. The fiber bundle is connected to the light cone of the endoscope 3. The fluorescence signal is propagated through the fiber bundle to one of the split ends of the multi-in-one fiber bundle 4. After being filtered by the filter 501, fluorescence with a wavelength greater than 1000nm is obtained and transmitted to the photodetector 502. The current amplifier is electrically connected to the photodetector and converts the APD output current into a 0-5V voltage signal.

[0083] S3: Data Acquisition and Transmission

[0084] ①Synchronous sampling: The data acquisition card 801 samples at a rate of 100kS / s at the rising edge of the trigger pulse of the MEMS controller 803. 100 points are collected in each x-axis cycle (1ms), and a total of 10,000 points are collected in each frame (10ms).

[0085] ② Real-time data transmission: The data acquisition card 801 transmits the raw voltage data to the memory of the host computer 802 via the USB interface.

[0086] S4: Fluorescence image generation:

[0087] ①Pixelation mapping: The fluorescence intensity (0-10V) of 10,000 sampling points is interpolated to a 512×512 grid according to the coordinates, and the missing pixels are filled by bicubic interpolation to generate a fluorescence image.

[0088] ② Dynamic noise reduction: A real-time moving average filter (window size 5×5 pixels) is applied to suppress shot noise and APD dark current interference, thereby achieving noise reduction processing of fluorescence images.

[0089] ③ The real-time synchronous display of white light and fluorescence images is achieved by controlling the host computer 802. The imaging device described in this invention is used to image an ICG (indocyanine green) sample, and the final white light imaging and near-infrared II region imaging results are as follows: Figure 3 As shown.

[0090] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A short-wave infrared fluorescence endoscopic imaging device, characterized in that, include: The system comprises an excitation light source module (1), a scanning module (2), an endoscope (3), a multi-functional fiber bundle (4), a short-wave infrared detection module (5), a white light illumination module (6), a white light imaging module (7), a control and data acquisition module (8), and a dichroic mirror (9). The endoscope (3) includes an imaging channel and an illumination channel. The imaging channel has an eyepiece port (301) and an objective lens port (304) at both ends. The illumination channel has an illumination channel inlet (302) and an illumination channel outlet (303) at both ends. The excitation light source module (1) is optically connected to the scanning module (2), the scanning module (2) and the white light imaging module (7) are optically connected to the eyepiece port (301) through a dichroic mirror (9), the short-wave infrared detection module (5) and the white light illumination module (6) are optically connected to the illumination channel entrance (302) through a multi-in-one fiber bundle (4), and the control and data acquisition module (8) is electrically connected to the scanning module (2), the short-wave infrared detection module (5), and the white light imaging module (7) respectively. The excitation light source module (1) generates a laser beam of a preset wavelength to the scanning module (2); the scanning module (2) modulates the laser beam into a beam with a specified scanning frequency and scanning path and couples it to the eyepiece port (301) via the dichroic mirror (9), enters the imaging channel, and exits from the objective lens port (304) to the sample. The fluorescence signal generated by the sample is emitted to the short-wave infrared detection module (5) after passing through the illumination channel and the multi-in-one fiber bundle (4); the short-wave infrared detection module (5) converts the received fluorescence signal into an electrical signal; the white light illumination module (6) is the white light imaging module. The system provides white light for illumination. The white light enters the illumination channel after passing through the multi-in-one fiber bundle (4) and the illumination channel entrance (302), and is emitted to the sample from the illumination channel exit (303). The visible light signal reflected by the sample passes through the imaging channel and the dichroic mirror (9) and reaches the white light imaging module (7). The white light imaging module (7) generates a white light image. The control and data acquisition module (8) is used to provide the scanning frequency and scanning path, acquire the white light image, and acquire the electrical signal for pixel mapping processing to obtain the fluorescence image, so as to realize the real-time synchronous display of the white light image and the fluorescence image.

2. The short-wave infrared fluorescence endoscopic imaging device according to claim 1, characterized in that, The excitation light source module (1) includes a laser (101) that generates a laser beam with a wavelength of 650nm-1064nm. The laser (101) is a spatial light laser, a fiber laser, or an LED.

3. The short-wave infrared fluorescence endoscopic imaging device according to claim 2, characterized in that, The scanning module (2) includes a MEMS scanning micromirror (201) and a beam shaping lens group (202). The laser beam generated by the laser (101) is incident on the surface of the MEMS scanning micromirror (201), and after passing through the dichroic mirror (9) and the beam shaping lens group (202) to be compressed, it is coupled to the eyepiece port (301).

4. The short-wave infrared fluorescence endoscopic imaging device according to claim 1, characterized in that, The bundled end of the multi-in-one fiber bundle (4) is connected to the optical path of the lighting channel entrance (302), one of the split ends of the multi-in-one fiber bundle (4) is connected to the optical path of the white light lighting module (6), and the remaining split ends of the multi-in-one fiber bundle (4) are connected to the optical path of the short-wave infrared detection module (5). The white light illumination module (6) includes a white light source (601), which is connected to one of the beam-splitter optical paths of the multi-in-one fiber bundle (4).

5. The short-wave infrared fluorescence endoscopic imaging device according to claim 1, characterized in that, The shortwave infrared detection module (5) includes a filter (501) and a photodetector (502) connected in sequence. The filter (501) is connected to the beam splitter optical path of the multi-in-one fiber bundle (4), and the photodetector (502) is electrically connected to the control and data acquisition module (8).

6. The short-wave infrared fluorescence endoscopic imaging device according to claim 5, characterized in that, The filter (501) is a short-wave infrared long-pass filter; The photodetector (502) includes an indium gallium arsenide avalanche photodiode detector, a photomultiplier tube, and a superconducting nanowire single-photon detector.

7. The short-wave infrared fluorescence endoscopic imaging device according to claim 1, characterized in that, The white light imaging module (7) includes an imaging lens group (701) and a camera (702). The visible light signal reflected by the sample is collected at the eyepiece port (301) after passing through the imaging channel. After being reflected and split by the dichroic mirror (9), it is imaged on the camera (702) by the imaging lens group (701).

8. The short-wave infrared fluorescence endoscopic imaging device according to claim 1, characterized in that, The control and data acquisition module (8) includes a data acquisition card (801), a host computer (802), and a MEMS controller (803). The data acquisition card (801) is connected to a photodetector (502). The data acquisition card (801), the MEMS controller (803), and the camera (702) are all connected to the host computer (802). The MEMS controller (803) is connected to a MEMS scanning micromirror (201). The host computer (802) synchronously controls the scanning frequency of the MEMS scanning micromirror (201) and the sampling frequency of the data acquisition card (801). The data acquisition card (801) acquires electrical signals from the photodetector (502) and sends them to the host computer (802). The host computer (802) performs pixel mapping processing of the fluorescence intensity data to obtain a fluorescence image. The camera (702) sends the white light image it generates to the host computer (802). The host computer (802) realizes real-time synchronous display of the white light image and the fluorescence image.

9. The short-wave infrared fluorescence endoscopic imaging device according to claim 8, characterized in that, The sampling frequency of the data acquisition card (801) is an integer multiple of the scanning frequency of the MEMS scanning micromirror (201).

10. An imaging method based on the shortwave infrared fluorescence endoscopic imaging device according to any one of claims 1-9, characterized in that, Includes the following steps: Step S1: The white light illumination module (6) is connected to the illumination channel entrance (302) through the multi-in-one fiber bundle (4) to illuminate the sample. The visible light signal reflected by the sample is imaged on the target surface of the camera (702) through the imaging channel, beam shaping lens group (202), dichroic mirror (9) for beam splitting and reflection, and imaging lens group (701). The white light image is then collected and displayed in real time by the host computer (802). Step S2: The host computer (802) issues a command to control the scanning path of the MEMS scanning micromirror (201) and sends the command to the data acquisition card (801) to synchronously control the scanning frequency of the MEMS scanning micromirror (201) and the sampling frequency of the data acquisition card (801) to achieve real-time matching of fluorescence signal and scanning coordinates. Step S3: The laser beam emitted by the excitation light source module (1) is modulated by the MEMS scanning micromirror (201), then condensed by the dichroic mirror (9) and the beam shaping lens group (202) and coupled to the eyepiece port (301). The beam is transmitted to the sample through the imaging channel, and the fluorescence signal generated by the sample is transmitted to the entrance of the illumination channel (302) through the illumination channel. The beam is then emitted to the short-wave infrared detection module (5) through the multi-in-one fiber bundle (4). After being filtered by the filter (501), the beam is collected by the photodetector (502) and converted into an electrical signal. Step S4: The electrical signal is collected by the data acquisition card (801) at a specified frequency and transmitted to the host computer (802). The host computer (802) performs pixel mapping processing of the fluorescence intensity data in real time to obtain the fluorescence image and realize the real-time synchronous display of the white light image and the fluorescence image.

Images