Endoscope

Abstract

The present application provides an endoscope, which relates to the field of optical imaging technology. The endoscope includes: an optical signal transmission component for transmitting an optical signal, wherein the optical signal includes an excitation light signal and a fluorescence signal corresponding to the excitation light signal; and an optical signal focusing component including a super lens, which is used to focus the excitation light signal to the sample to be photographed and / or focus the fluorescence signal to the optical signal transmission component. The endoscope provided by the present application uses a super lens as an optical signal focusing component, which achieves the purpose of focusing the optical signal and eliminates the chromatic aberration of the optical signal. In addition, the super lens provided by the present application has the advantage of being ultra-light and thin, and can take into account the packaging integration of the endoscope while satisfying the conditions of larger aperture and larger field of view imaging, so as to further miniaturize the endoscope.

Description

Technical Field

[0001] The present application relates to the field of optical imaging technology, and in particular to an endoscope. Background Art

[0002] Multiphoton endoscopic microscopy technology has the advantages of better tissue penetration and signal-to-noise ratio, good focusing, less tissue photodamage and photobleaching, and is widely used in biomedical imaging and diagnosis of clinical diseases.

[0003] However, in the current multiphoton endoscope system, the selection of optical objective lenses is limited, and there are disadvantages such as severe chromatic aberration, poor imaging quality, high cost, and difficult processing. Therefore, how to apply high-quality optical objective lenses to multiphoton endoscope systems has become an urgent problem to be solved. Summary of the invention

[0004] In order to solve the above technical problems, the present application is proposed. An embodiment of the present application provides an endoscope.

[0005] In a first aspect, an embodiment of the present application provides an endoscope, comprising: an optical signal transmission component for transmitting an optical signal, wherein the optical signal comprises an excitation light signal and a fluorescence signal corresponding to the excitation light signal; and an optical signal focusing component having a super lens, for focusing the excitation light signal to a sample to be photographed and / or focusing the fluorescence signal to the optical signal transmission component.

[0006] In combination with the first aspect, in some implementations of the first aspect, the optical signal focusing component is located in an optical path corresponding to the optical signal transmission component and the sample to be photographed.

[0007] In combination with the first aspect, in certain implementations of the first aspect, the metalens includes a plurality of microstructure units distributed in an array, wherein the phase modulation information corresponding to each microstructure unit is equal to the phase information corresponding to the microstructure unit, and the height corresponding to the microstructure unit is determined based on the phase modulation information corresponding to the microstructure unit.

[0008] In combination with the first aspect, in certain implementations of the first aspect, the phase modulation information corresponding to the microstructure unit is determined based on the height, refractive index information and optical signal wavelength corresponding to the microstructure unit, wherein the optical signal wavelength includes the excitation light signal wavelength or the fluorescence signal wavelength.

[0009] In combination with the first aspect, in certain implementations of the first aspect, the phase information corresponding to the microstructure unit is determined based on the radius information of the metalens, wherein the radius information includes the normalized radius of the metalens, and the phase information is determined by performing a fitting operation on an even-order polynomial of the normalized radius.

[0010] In combination with the first aspect, in certain implementations of the first aspect, the metalens surface includes a plurality of sampling points around the center of the metalens, and the normalized radius is determined based on the ratio of the coordinate information of the positions of the sampling points relative to the center of the metalens to the maximum effective radius information of the metalens.

[0011] In combination with the first aspect, in certain implementations of the first aspect, the microstructure unit includes a micro-column unit, the shape of the micro-column unit is at least one of a rectangular parallelepiped, an elliptical cylinder, and a cylinder, and the material of the micro-column unit includes at least one of silicon, titanium dioxide, and gallium nitride.

[0012] In combination with the first aspect, in certain implementations of the first aspect, the microstructure unit includes a substrate, and a material of the substrate includes silicon dioxide.

[0013] In combination with the first aspect, in certain implementations of the first aspect, the endoscope further includes: a scanning and coupling component located in the optical path corresponding to the optical signal generating and receiving component and the optical signal focusing component, for scanning and coupling the optical signal, wherein the optical signal generating and receiving component is used to generate an excitation light signal and receive a fluorescence signal.

[0014] In combination with the first aspect, in certain implementations of the first aspect, the optical signal transmission component includes an optical fiber; the scanning and coupling component includes a piezoelectric ceramic scanner and a coupling lens, the piezoelectric ceramic scanner is used to receive a preset modulation signal applied by the signal driving and image construction component to drive the optical signal transmission component to perform a scanning operation, and the coupling lens is used to couple the optical signal to confine the optical signal within the optical signal transmission component.

[0015] In combination with the first aspect, in certain implementations of the first aspect, the optical signal transmission component includes an optical fiber bundle; the scanning and coupling component includes a resonant galvanometer and / or a micro-electromechanical device, the resonant galvanometer and / or the micro-electromechanical device are used to receive a preset modulation signal applied by the signal driving and image construction component to drive the optical signal transmission component to perform a scanning operation, and the scanning and coupling component also includes a coupling lens, the coupling lens is used to couple the optical signal to confine the optical signal within the optical signal transmission component.

[0016] In combination with the first aspect, in certain implementations of the first aspect, the endoscope further includes: an optical signal generating and receiving component for generating an excitation light signal and receiving a fluorescent signal.

[0017] In combination with the first aspect, in certain implementations of the first aspect, the endoscope further includes: a signal driving and image construction component located in an optical path corresponding to the optical signal generating and receiving component and the scanning and coupling component, the signal driving and image construction component being used to apply a preset modulation signal to the scanning and coupling component, and to perform image construction operations based on the fluorescent signal received by the optical signal generating and receiving component.

[0018] An embodiment of the present application provides an endoscope, in which the optical signal focusing component of the endoscope adopts a superlens objective lens, which achieves the purpose of focusing the excitation light signal to the sample to be photographed and / or focusing the fluorescence signal to the optical signal transmission component. The superlens provided by the present application is a new type of binary optical element, which is a lens whose surface is designed and composed of a two-dimensional subwavelength array structure. In other words, the size of the microstructure unit of the superlens is at the subwavelength level, and the phase information of the optical signal can be flexibly adjusted. The present application applies the superlens to the endoscope, and realizes the achromatic function of the excitation light signal and the fluorescence signal by designing the structure of the superlens. In addition, the superlens provided by the present application has the advantage of being ultra-light and thin, and can take into account the packaging integration of the endoscope while satisfying the conditions of larger aperture and larger field of view imaging, so as to further miniaturize the endoscope. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] By describing the embodiments of the present application in more detail in conjunction with the accompanying drawings, the above and other purposes, features and advantages of the present application will become more apparent. The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation of the present application. In the accompanying drawings, the same reference numerals generally represent the same components or steps.

[0020] Figure 1 Shown is a schematic structural diagram of a microstructure unit provided by an exemplary embodiment of the present application.

[0021] Figure 2 Shown is a schematic structural diagram of an endoscope provided by an exemplary embodiment of the present application.

[0022] Figure 3 Shown is a schematic structural diagram of an endoscope provided by another exemplary embodiment of the present application.

[0023] Figure 4 Shown is a schematic structural diagram of an endoscope provided by another exemplary embodiment of the present application.

[0024] Figure 5 Shown is a schematic structural diagram of an endoscope provided by another exemplary embodiment of the present application. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0026] Chromatic aberration, also known as dispersion, is caused by the camera lens not focusing light of different wavelengths on the same focal plane (light of different wavelengths has different focal lengths). In other words, chromatic aberration refers to the phenomenon that a single lens cannot focus all wavelengths of light on the same point in optics.

[0027] The traditional method of chromatic aberration correction is to achieve it by superimposing multiple lenses, but this will cause problems such as bulky volume, inability to be easily integrated, high cost, and difficulty in processing. The superlens provided in this application is a lens designed by a two-dimensional sub-wavelength array structure surface. It is a supersurface that can modulate the incident light signal into a spherical wave at the exit and focus it. It can flexibly adjust the phase information of the light signal, thereby eliminating the chromatic aberration of light signals of different wavelengths and improving the imaging quality.

[0028] The focusing function of the superlens provided in the present application is to introduce phase distortion between two media to replace the phase accumulation of electromagnetic waves in traditional lenses, thereby forming a specific refractive effect, that is, to introduce a gradient refractive index at the junction of the two media, so as to control the refracted light beam to achieve emission in any direction. Compared with the micro multi-photon endoscope composed of a commonly used gradient variable refractive index lens or a multi-piece ordinary optical lens in the prior art, the superlens provided in the present application has its unique advantages. The superlens is much smaller than other types of lenses in size, thickness, and weight, but can achieve a larger numerical aperture. The superlens also has a high transmittance for fluorescent signals, which improves the collection efficiency of fluorescence. In recent years, with the increasing maturity of electron beam etching technology, the difficulty of superlens processing has further decreased, and its unique structure can significantly improve the space utilization of the optical system. In addition, the present application applies the superlens to the endoscope, which can simplify the structure of the endoscope and improve the reliability of the in vivo multi-photon microscopic imaging results.

[0029] Figure 1 The structure diagram of the microstructure unit provided by an exemplary embodiment of the present application is shown. Specifically, the metalens includes a plurality of microstructure units distributed in an array. The following explanation is given by taking the microstructure unit as a rectangular parallelepiped structure as an example.

[0030] like Figure 1As shown, the microstructure unit provided in the embodiment of the present application includes a micro-column unit 1 and a substrate 2. The shape of the micro-column unit 1 is a rectangular parallelepiped. The constituent materials of the micro-column unit 1 include at least one of silicon, titanium dioxide, and gallium nitride. The size of the micro-column unit 1 is sub-wavelength order. The size of the super lens can reach the radius of centimeters and the thickness of millimeters. When it is introduced into the field of multi-photon microscopy, while achieving focusing under large numerical aperture and large field of view imaging conditions, the structure of the endoscope is greatly simplified, the weight of the overall equipment is greatly reduced, and the reliability of the in-vivo multi-photon microscopy imaging results is improved. In addition, the shape of the micro-column unit 1 can also be an elliptical cylinder or a cylinder, and the constituent materials of the substrate 2 include silicon dioxide.

[0031] In an embodiment of the present application, the length of the micro-column unit 1 is a, the width is b, and the height is h. The wavelength of the excitation light signal in the embodiment of the present application is 800 nanometers, and the wavelength of the fluorescence signal is 515 nanometers. In order to achieve the achromatic function of the above-mentioned excitation light signal and fluorescence signal, according to the orthogonal nature of the polarization directions of the excitation light signal and the fluorescence signal, the excitation light signal can be phase modulated by the length of the micro-column unit 1, and the fluorescence signal can be phase modulated by the width of the micro-column unit 1 as an example for explanation.

[0032] In one embodiment of the present application, the phase information corresponding to the microstructure unit is determined based on the radius information of the metalens, and the radius information includes the normalized radius of the metalens. Exemplarily, the above phase information is determined by fitting an even-order polynomial of the normalized radius, that is, the following formula (1).

[0033]

[0034] In the above formula (1), φ1 is the phase information corresponding to the microstructure unit, a k is the fitting coefficient, ρ is the normalized radius of the superlens, and ρ 2k is an even power of the normalized radius of the metalens, and n is the order of the polynomial.

[0035] In one embodiment of the present application, the metalens surface includes a plurality of sampling points around the center of the metalens, and it can be understood that each sampling point corresponds to a microstructure unit arranged at the sampling point. The normalized radius of the metalens is determined based on the ratio of the coordinate information of the position of the sampling point relative to the center of the metalens to the maximum effective radius information of the metalens, and the specific expression is as shown in the following formula (2).

[0036]

[0037] In the above formula (2), x and y are the horizontal coordinate information and vertical coordinate information of the position of the above sampling point relative to the center of the super lens, r max is the maximum effective radius information of the superlens.

[0038] In one embodiment of the present application, after determining the phase information corresponding to the microstructure unit, a suitable shape of the microcolumn unit 1 is selected and the structural parameter information (such as length, width, and height) of the microcolumn unit 1 is determined, and the finite element simulation method is used to simulate the above-determined microcolumn unit. The phase modulation information corresponding to each microstructure unit is equal to the phase information corresponding to the microstructure unit, that is, the phase information corresponding to the above microstructure unit is equal to the phase modulation information corresponding to the microstructure unit set at the position. Exemplarily, the phase modulation information corresponding to the microstructure unit is determined according to the following formula (3).

[0039]

[0040] In the above formula (3), φ2 is the phase modulation information corresponding to the microstructure unit, n eff is the refractive index information corresponding to the microstructure unit (such as the effective refractive index), H is the height corresponding to the microstructure unit (ie, the h mentioned above), and λ is the wavelength of the light signal (such as the excitation light signal wavelength or the fluorescence signal wavelength).

[0041] It can be understood from the above formulas (1) and (3) that the height corresponding to the microstructure unit set at the position can be calculated by the phase information φ1 corresponding to the above microstructure unit and the phase modulation information φ2 corresponding to the microstructure unit set at the position being equal. In addition, the length a and width b corresponding to the microstructure unit set at the position are determined by the phase information corresponding to the position. A preset size change interval is selected so that the phase information modulated by the preset size change interval can include a phase range of 0 to 2π.

[0042] It can be understood that in one embodiment of the present application, the volume ratio difference between the micro-column unit 1 and the air in the micro-structure unit is used to generate the refractive index information corresponding to the above-mentioned micro-structure unit, so that the optical path of the light signal in the medium changes. Micro-column units 1 of different sizes cause the light signal to have different phase delays when it is emitted, resulting in discontinuous phase distortion. In order to achieve the focusing function of the superlens, the phase delay of the micro-column unit 1 at the center of the superlens should be greater than the phase delay of the micro-column unit 1 at the edge. After a 2π phase delay is completed from the center to the edge of the superlens, a micro-column unit 1 that can produce the next 2π phase delay is placed immediately. The construction of the superlens can be completed by placing micro-column units 1 of a certain size that can produce the required phase at different positions.

[0043] The metalens provided in the embodiment of the present application realizes the achromatic function of the excitation light signal and the fluorescence signal by flexibly adjusting the phase information of the light signal and controlling the light signal to be emitted in any direction, thereby eliminating the chromatic aberration of light signals of different wavelengths and improving the imaging quality.

[0044] Figure 2 FIG. 1 is a schematic diagram of the structure of an endoscope provided by an exemplary embodiment of the present application. Figure 2 As shown, the endoscope provided by the present application includes an optical signal generating and receiving component S1, an optical signal transmitting component S2, a scanning and coupling component S3, an optical signal focusing component S4, a sample to be photographed S5 and a signal driving and image constructing component S6.

[0045] In one embodiment of the present application, the optical signal generating and receiving component S1 includes a femtosecond pulse laser and a fluorescence detector, the optical signal transmission component S2 includes a solid double-clad optical fiber or a hollow double-clad optical fiber, the scanning and coupling component S3 includes a piezoelectric ceramic scanner, the optical signal focusing component S4 includes a superlens, and the sample to be photographed S5 includes a biological sample tissue, wherein the piezoelectric ceramic scanner includes a piezoelectric ceramic tubular driver and / or a square piezoelectric ceramic sheet driver, etc. The embodiment of the present application does not further limit the specific implementation form of the piezoelectric ceramic scanner.

[0046] Exemplarily, the optical signal generating and receiving component S1 generates an excitation light signal, which is output from the optical signal generating and receiving component S1 and enters the fiber core of the optical signal transmission component S2. The scanning and coupling component S3 receives a preset modulation signal applied by the signal driving and image construction component S6 to drive the optical signal transmission component S2 to perform a scanning operation, thereby outputting an excitation light signal within a certain spatial range. The excitation light signal is further focused on the sample to be photographed S5 through the optical signal focusing component S4.

[0047] It can be understood that due to the multi-photon excitation effect, the ground state fluorescent molecules or atoms absorb multiple photons at the same time to become excited states, and radiate fluorescent photons through the relaxation process. Multi-photon imaging has the advantages of deep penetration depth, which can achieve deep imaging, small photobleaching and photodamage effects, and optical tomography. In addition, in addition to exciting fluorescent signals, multi-photons can also excite harmonic signals of different wavelengths, providing more abundant information and other advantages.

[0048] In one embodiment of the present application, the excitation light signal generates a fluorescence signal and a harmonic signal at the sample to be photographed S5. The fluorescence signal and the harmonic signal return through the original optical path, and pass through the optical signal focusing component S4, the scanning and coupling component S3, the optical signal transmission component S2 in reverse order to the optical signal generation and receiving component S1, and complete the image construction through the signal driving and image construction component S6.

[0049] The endoscope provided in the embodiment of the present application applies the superlens to the field of multiphoton microscopy. Compared with the existing endoscopes, the embodiment of the present application has greatly simplified the structure of the endoscope while taking into account the focusing under the conditions of large numerical aperture and large field of view imaging, and the weight of the overall equipment has been greatly reduced, which realizes the further packaging and integration of the endoscope, achieves lighter endoscopic imaging, improves the reliability of in vivo multiphoton microscopic imaging results, and also brings higher scientific value to in vivo endoscopic imaging. That is, the endoscope based on the superlens proposed in the embodiment of the present application solves the problem that the conventional micro-multiphoton endoscope in the prior art uses a gradient variable refractive index lens or a multi-piece ordinary optical lens to scan and image the sample to be photographed, and there is a problem that the weight of the endoscope cannot be further reduced without taking into account the imaging field of view and resolution at the same time.

[0050] Figure 3 FIG. 1 is a schematic diagram of the structure of an endoscope provided by another exemplary embodiment of the present application. Figure 2 Based on the embodiment shown, Figure 3 The embodiment shown is described below in detail. Figure 3 The embodiment shown and Figure 2 The differences and similarities of the illustrated embodiments are not described in detail.

[0051] like Figure 3 As shown, the endoscope provided by the present application includes a dichroic mirror S7, a coupling lens S8, a filter S9, a converging lens S10, and a photodetector S11.

[0052] In one embodiment of the present application, the optical signal generating and receiving component S1 generates an excitation light signal, which is output from the optical signal generating and receiving component S1, passes through a dichroic mirror S7, and is coupled by a coupling lens S8 into the core of the optical signal transmission component S2. The scanning and coupling component S3 receives a preset modulation signal applied by the signal driving and image construction component S6 to drive the optical signal transmission component S2 to perform a scanning operation, thereby outputting an excitation light signal within a certain spatial range. The excitation light signal is further focused on the sample to be photographed S5 through the optical signal focusing component S4.

[0053] It can be understood that the dichroic mirror S7 is used to separate the excitation light signal from the fluorescence signal in the optical path, thereby increasing the efficiency of collecting the fluorescence signal, and the coupling lens S8 is used to couple the excitation light signal into the core of the optical signal transmission component S2.

[0054] In one embodiment of the present application, the excitation light signal generates a fluorescence signal and a harmonic signal at the sample S5 to be photographed. The fluorescence signal and the harmonic signal are reversely transmitted through the light signal focusing component S4, the scanning and coupling component S3, the light signal transmission component S2, the coupling lens S8, the dichroic mirror S7 to the filter S9, and then pass through the converging lens S10 and the photodetector S11 to the signal driving and image construction component S6 to complete the image construction.

[0055] It can be understood that the filter S9 is used to filter out the fluorescent signal, further increasing the efficiency of collecting the fluorescent signal, the converging lens S10 is used to converge the fluorescent signal, increasing the energy of the collected fluorescent signal, and the photodetector S11 is used to convert the optical signal into an electrical signal, which is beneficial to the subsequent image construction, display and analysis.

[0056] The endoscope provided by the embodiment of the present application applies the superlens to the field of multiphoton microscopy, which solves the problem that the conventional micro multiphoton endoscope uses a gradient refractive index lens or a multi-piece ordinary optical lens to scan and image the sample to be photographed, and there is a problem that the weight of the endoscope cannot be further reduced while taking into account the imaging field of view and resolution. In addition, the endoscope provided by the embodiment of the present application also includes a dichroic mirror, a coupling lens, a filter, a converging lens, and a photodetector. The dichroic mirror is used to separate the excitation light signal and the fluorescence signal in the optical path, the filter filters out the fluorescence signal, and the converging lens converges the fluorescence signal, thereby increasing the efficiency of collecting the fluorescence signal and the energy of the fluorescence signal; the coupling lens couples the excitation light signal into the core of the optical signal transmission component, thereby achieving the purpose of collecting the excitation light signal; the photodetector converts the optical signal into an electrical signal, which is conducive to the construction, display and analysis of the later image.

[0057] Figure 4 FIG. 1 is a schematic diagram of the structure of an endoscope provided by another exemplary embodiment of the present application. Figure 2 Based on the embodiment shown, Figure 4 The embodiment shown is described below in detail. Figure 4 The embodiment shown and Figure 2 The differences and similarities of the illustrated embodiments are not described in detail.

[0058] like Figure 4 As shown, the optical signal transmission component S2 includes an optical fiber bundle, and the scanning and coupling component S3 includes a scanning component and a coupling component, wherein the scanning component includes a micro-electromechanical device (such as a micro-electromechanical scanning galvanometer) and / or a resonant galvanometer, and the coupling component is the above-mentioned coupling lens S8.

[0059] Exemplarily, the optical signal generating and receiving component S1 generates an excitation light signal, which is output from the optical signal generating and receiving component S1 and enters the fiber core of the optical signal transmission component S2 through the scanning and coupling component S3. The scanning and coupling component S3 receives a preset modulation signal applied by the signal driving and image construction component S6 to drive the optical signal transmission component S2 to perform a scanning operation, thereby outputting an excitation light signal within a certain spatial range. The excitation light signal is further focused on the sample to be photographed S5 through the optical signal focusing component S4.

[0060] Understandably, Figure 4 The embodiment shown and Figure 2 The differences between the embodiments shown are mainly Figure 4 The illustrated embodiment is based on a system scanning mechanism of a fiber bundle, which is at the proximal end of the fiber bundle (i.e., close to the main body of the optical system), while a system based on single fiber scanning (i.e., Figure 2 The scanning mechanism is at the end of the optical fiber (i.e., far away from the optical signal generating and receiving component S1), and most of them use piezoelectric ceramics or piezoelectric chips to drive a single optical fiber to achieve scanning. Due to the limitations of current science and technology, it is difficult to make the end size of a single optical fiber scanning mechanism very small, and the longer part cannot be bent. This feature limits the scope of use of the single optical fiber scanning system.

[0061] exist Figure 2 In the focusing endoscope that realizes imaging by remote scanning of a single optical fiber used in the illustrated embodiment, this method generally uses a piezoelectric chip or a piezoelectric ceramic to drive the optical fiber cantilever to vibrate to realize scanning. This scanning method can realize raster scanning or "tornado" scanning. Here, a single optical fiber not only outputs the generated excitation light signal, but is also used to collect the returned fluorescence signal. The core of a single optical fiber is only a few microns, and it can also play the role of detecting small holes, but the original image obtained using this type of scanning component will have a large distortion, and distortion correction needs to be performed according to the actual scanning trajectory. This scanning method can achieve very high optical resolution, but due to the limitations of the scanning mechanism, it is difficult to achieve a small physical size at the far end of the scanning probe. In addition, the implementation form based on piezoelectric chips or piezoelectric ceramics to drive optical fiber scanning requires voltage drive, which poses a potential threat to both patients and doctors. Therefore, considering safety and patient comfort, it is generally preferred to use an endoscopic imaging method based on an optical fiber bundle (i.e. Figure 4 Embodiment shown).

[0062] In one embodiment of the present application, the use of an optical fiber bundle to transmit light signals and images can place the scanning mechanism at the proximal end of the optical system. The scanning system based on the optical fiber bundle can be inserted into the working channel of a conventional endoscope because the distal end has a smaller size. In addition, the scanning system based on the optical fiber bundle is safer because the distal end is not charged. In addition, the fiber-optic focusing endoscopic imaging method combines the laser confocal microscopy imaging technology and the endoscopic imaging technology, which can not only give play to the advantages of the flexibility of the optical fiber, but also retain the high resolution, high contrast and tomography characteristics of the confocal microscope. The endoscope provided in the embodiment of the present application inserts a soft optical fiber bundle into tissues or organs such as the inner surface of the respiratory tract, digestive tract, and urinary system that are not easily accessible to conventional imaging systems in the body to perform in vivo, real-time, non-destructive dynamic monitoring with subcellular resolution. In the detection application of clinical cancer, the endoscope provided in the embodiment of the present application has high sensitivity and specificity, making it possible to diagnose tiny lesions in vivo, greatly changing the diagnosis process of the disease.

[0063] The endoscope provided in the embodiment of the present application applies the superlens to the field of multiphoton microscopy, solving the problem that the conventional micro-multiphoton endoscope in the prior art uses a gradient-variable refractive index lens or a multi-piece ordinary optical lens to scan and image the sample to be photographed, and there is a problem that the weight of the endoscope cannot be further reduced without taking into account both the imaging field of view and the resolution. In addition, the endoscope provided in the embodiment of the present application uses an optical fiber bundle as an optical signal transmission component. The scanning system based on the optical fiber bundle can be inserted into the working channel of a conventional endoscope because the distal end has a smaller size. The soft optical fiber bundle is inserted into tissues or organs such as the inner surface of the respiratory tract, digestive tract, and urinary system that are not easily accessible to conventional imaging systems in the body to perform in vivo, real-time, and non-destructive dynamic monitoring with subcellular resolution. In the application of clinical cancer detection, the endoscope provided in the embodiment of the present application has high sensitivity and specificity, making it possible to diagnose tiny lesions in vivo, greatly changing the diagnosis process of the disease.

[0064] Figure 5 FIG. 1 is a schematic diagram of the structure of an endoscope provided by another exemplary embodiment of the present application. Figure 4 Based on the embodiment shown, Figure 5 The embodiment shown is described below in detail. Figure 5 The embodiment shown and Figure 4 The differences and similarities of the illustrated embodiments are not described in detail.

[0065] like Figure 5As shown, in one embodiment of the present application, the optical signal generating and receiving component S1 generates an excitation light signal, and the excitation light signal is output from the optical signal generating and receiving component S1 through the dichroic mirror S7, and then enters the coupling lens S8 through the scanning and coupling component S3. The scanning and coupling component S3 receives the preset modulation signal applied by the signal driving and image construction component S6 to drive the optical signal transmission component S2 to perform a scanning operation, and then outputs the excitation light signal within a certain spatial range, and is coupled by the coupling lens S8 into the core of the optical signal transmission component S2. The excitation light signal further passes through the optical signal focusing component S4 to be focused on the sample S5 to be photographed.

[0066] In one embodiment of the present application, the excitation light signal generates a fluorescence signal and a harmonic signal at the sample S5 to be photographed. The fluorescence signal and the harmonic signal pass through the light signal focusing component S4, the light signal transmission component S2, the coupling lens S8, the scanning and coupling component S3, the dichroic mirror S7 to the filter S9 in reverse order, and pass through the converging lens S10 and the photodetector S11 to the signal driving and image construction component S6 to complete the image construction.

[0067] The endoscope provided by the embodiment of the present application applies the superlens to the field of multiphoton microscopy, which solves the problem that the conventional micro multiphoton endoscope uses a gradient refractive index lens or a multi-piece ordinary optical lens to scan and image the sample to be photographed, and there is a problem that the weight of the endoscope cannot be further reduced while taking into account the imaging field of view and resolution. In addition, the endoscope provided by the embodiment of the present application also includes a dichroic mirror, a coupling lens, a filter, a converging lens, and a photodetector. The dichroic mirror is used to separate the excitation light signal and the fluorescence signal in the optical path, the filter filters out the fluorescence signal, and the converging lens converges the fluorescence signal, thereby increasing the efficiency of collecting the fluorescence signal and the energy of the fluorescence signal; the coupling lens couples the excitation light signal into the core of the optical signal transmission component, thereby achieving the purpose of collecting the excitation light signal; the photodetector converts the optical signal into an electrical signal, which is conducive to the construction, display and analysis of the later image.

[0068] The basic principles of the present application are described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, effects, etc. mentioned in the present application are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. are required by each embodiment of the present application. In addition, the specific details disclosed above are only for the purpose of illustration and ease of understanding, not for limitation, and the above details do not limit the present application to being implemented by adopting the above specific details.

[0069] The block diagrams of the devices, apparatuses, equipment, and systems involved in this application are only illustrative examples and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagram. As will be appreciated by those skilled in the art, these devices, apparatuses, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open words, referring to "including but not limited to", and can be used interchangeably with them. The words "or" and "and" used here refer to the words "and / or" and can be used interchangeably with them, unless the context clearly indicates otherwise. The words "such as" used here refer to the phrase "such as but not limited to", and can be used interchangeably with them.

[0070] It should also be noted that in the apparatus, device and method of the present application, each component or each step can be decomposed and / or recombined. Such decomposition and / or recombination should be regarded as equivalent solutions of the present application.

[0071] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present application. Therefore, the present application is not intended to be limited to the aspects shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0072] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims

1. An endoscope, characterized in that: Applications in multiphoton microscopy include: An optical signal transmission component, used for transmitting an optical signal, wherein the optical signal includes a femtosecond pulse excitation optical signal for multiphoton microscopic imaging and a multiphoton excitation fluorescence signal corresponding to the femtosecond pulse excitation optical signal, and the optical signal transmission component includes a solid-core double-clad optical fiber or a hollow-core double-clad optical fiber; An optical signal focusing component with a super lens, used to focus the femtosecond pulse excitation optical signal to the sample to be photographed and / or focus the multi-photon excitation fluorescence signal and harmonic signal to the optical signal transmission component; A dichroic mirror, used for separating the excitation light signal from the fluorescence signal in an optical path; A coupling lens is used to couple the excitation light signal into the fiber core of the optical signal transmission component.

2. The endoscope according to claim 1, characterized in that The optical signal focusing component is located in the optical path corresponding to the optical signal transmission component and the sample to be photographed.

3. The endoscope according to claim 1 or 2, characterized in that: The superlens includes a plurality of microstructure units distributed in an array, wherein the phase modulation information corresponding to each of the microstructure units is equal to the phase information corresponding to the microstructure unit, and the height corresponding to the microstructure unit is determined based on the phase modulation information corresponding to the microstructure unit.

4. The endoscope according to claim 3, characterized in that The phase modulation information corresponding to the microstructure unit is determined based on the height, refractive index information and optical signal wavelength corresponding to the microstructure unit, wherein the optical signal wavelength includes the femtosecond pulse excitation optical signal wavelength or the multi-photon excitation fluorescence signal wavelength.

5. The endoscope according to claim 3, characterized in that The phase information corresponding to the microstructure unit is determined based on the radius information of the superlens, wherein the radius information includes the normalized radius of the superlens, and the phase information is determined by fitting an even-order polynomial of the normalized radius.

6. The endoscope according to claim 5, characterized in that The metalens surface includes a plurality of sampling points surrounding the center of the metalens, and the normalized radius is determined based on a ratio of coordinate information of positions of the sampling points relative to the center of the metalens to information about a maximum effective radius of the metalens.

7. The endoscope according to claim 3, characterized in that: The microstructure unit includes a micro-column unit, the shape of the micro-column unit is at least one of a cuboid, an elliptical cylinder, and a cylinder, and the material of the micro-column unit includes at least one of silicon, titanium dioxide, and gallium nitride.

8. The endoscope according to claim 3, characterized in that: The microstructure unit comprises a substrate, and the material of the substrate comprises silicon dioxide.

9. The endoscope according to claim 1 or 2, characterized in that: Also includes: The scanning and coupling component located in the optical path corresponding to the optical signal generating and receiving component and the optical signal focusing component is used to scan and couple the optical signal, wherein the optical signal generating and receiving component is used to generate the excitation light information and receive the fluorescence information.

10. The endoscope according to claim 9, characterized in that The optical signal transmission component includes an optical fiber, and the scanning and coupling component includes a piezoelectric ceramic scanner and a coupling lens. The piezoelectric ceramic scanner is used to receive a preset modulation signal applied by a signal driving and image construction component to drive the optical signal transmission component to perform a scanning operation, and the coupling lens is used to couple the optical signal to confine the optical signal within the optical signal transmission component.

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