OCT probe and imaging system

Abstract

The invention relates to an OCT probe and an imaging system. The OCT probe comprises an optical fiber collimator, a diffractive optical element, a focusing lens and a light splitting module which are sequentially arranged in the optical axis direction of the OCT probe, and the diffractive optical element is used for modulating a detection light beam from the optical fiber collimator so as to emit a needle-shaped light beam; the OCT probe further comprises an MEMS micro-scanning mirror, a reflection assembly and a camera module, the MEMS micro-scanning mirror and the reflection assembly are both arranged between the diffractive optical element and the focusing lens, and the needle-shaped light beam is reflected to the focusing lens by the MEMS micro-scanning mirror after passing through the reflection assembly. The light is emitted in parallel to the axial direction of the OCT probe after passing through the light splitting module; the optical axis direction of the camera module is perpendicular to the axial direction of the OCT probe, and reflected light from a target tissue is incident to the light splitting module in a manner of being parallel to the axial direction of the OCT probe and then is reflected to the camera module by the light splitting module.

Description

Technical Field

[0001] The present disclosure relates to the technical field of terminals, and particularly to an OCT probe and an imaging system. Background Art

[0002] Traditional OCT (Optical Coherence Tomography) is a non-invasive biomedical imaging technology and is widely used in in-vivo tissue imaging. However, existing OCT probes can only obtain internal information of tissues and cannot obtain the influence of tissue surfaces. Moreover, the detection beam of traditional OCT probes is a Gaussian beam, which is difficult to cover a relatively thick tissue layer during surgery and easily causes the loss of information on deep structures in the image. Summary of the Invention

[0003] The present disclosure provides an OCT probe and an imaging system to solve the deficiencies in related technologies.

[0004] According to the first aspect of the embodiments of the present disclosure, an OCT probe is provided, which includes a fiber collimator, a diffractive optical element, a focusing lens, and a beam splitting module arranged in sequence along the optical axis direction of the OCT probe. The diffractive optical element is used to modulate the detection beam from the fiber collimator to emit a needle-shaped beam.

[0005] The OCT probe further includes a MEMS micro scanner, a reflection assembly, and a camera module. The MEMS micro scanner and the reflection assembly are both arranged between the diffractive optical element and the focusing lens. The needle-shaped beam is reflected by the reflection assembly to the MEMS micro scanner and then to the focusing lens, and then exits parallel to the axial direction of the OCT probe after passing through the beam splitting module.

[0006] The optical axis direction of the camera module is perpendicular to the axial direction of the OCT probe. The reflected light from the target tissue is incident on the beam splitting module parallel to the axial direction of the OCT probe and is then reflected by the beam splitting module to the camera module.

[0007] Optionally, the reflection assembly includes a first right-angle reflector, a second right-angle reflector, and a third right-angle reflector. The reflection surfaces of the first right-angle reflector, the second right-angle reflector, and the third right-angle reflector all form an angle of 45° with the axial direction of the OCT probe.

[0008] The needle-shaped beam is incident on the second right-angled mirror perpendicular to the axis of the OCT probe after passing through the first right-angled mirror. The light beam emitted from the second right-angled mirror is incident on the third right-angled mirror parallel to the axis of the OCT probe. The light beam emitted from the third right-angled mirror is incident on the MEMS micro scanner perpendicular to the axis of the OCT probe. The reflecting surface of the MEMS micro scanner forms an angle of 45° with the axis of the OCT probe.

[0009] Optionally, the diffractive optical element is configured to perform phase modulation on the detection beam to form a needle-shaped beam. The needle-shaped beam has multiple foci within a set range in the outward direction along the axis of the OCT probe from the focus of the focusing lens.

[0010] Optionally, it further includes:

[0011] A mounting base, the mounting base includes a receiving cavity and a groove communicating with the receiving cavity. The focusing lens is disposed on one side of the mounting base facing the MEMS micro scanner. The beam splitting module is fixedly disposed within the mounting base, and the camera module is fixedly disposed within the groove.

[0012] Optionally, it further includes:

[0013] A cylindrical housing;

[0014] A cover body, the cover body is detachably connected to the cylindrical housing along the axis of the OCT probe. The cover body and the cylindrical housing are connected to form a device cavity;

[0015] A light-transmitting window sheet, the light-transmitting window sheet is disposed at one end of the cylindrical housing facing away from the cover body.

[0016] Optionally, it further includes an aperture disposed on the light-incident side of the camera module.

[0017] According to a second aspect of the embodiments of the present disclosure, there is provided an imaging system, including:

[0018] An OCT probe as described in any one of the foregoing embodiments;

[0019] A reference arm assembly;

[0020] An optical fiber coupler;

[0021] A light source, the output beam of the light source enters the optical fiber coupler, and after passing through the optical fiber coupler, part of it enters the reference arm assembly and part of it enters the OCT probe;

[0022] A spectrometer, the spectrometer generates an analog signal based on the interference signal formed by the beam returned from the reference arm assembly and the beam returned from the OCT probe;

[0023] A processor system that generates a three-dimensional OCT point cloud image of a target tissue in the depth direction based on the analog signal. The processor system is also communicatively connected to the camera module, and is configured to register the two-dimensional image information acquired by the camera module with the three-dimensional OCT point cloud image to obtain a fused image.

[0024] Optionally, the processor system is further configured to obtain Doppler blood flow information and superimpose the Doppler blood flow information on the fused image.

[0025] Optionally, the processor system is further configured to separately extract the image edge features of two adjacent frames of the three-dimensional OCT point cloud images, obtain the relative position relationship between the two adjacent frames of three-dimensional OCT point cloud images according to the difference between the image edge features of the two adjacent frames of three-dimensional OCT point cloud images, and control the movement of the OCT probe according to the relative position relationship.

[0026] The technical solutions provided by the embodiments of the present disclosure may include the following beneficial effects:

[0027] As can be seen from the above embodiments, in the present disclosure, a coaxial and common path design of the OCT detection optical path and the camera module shooting optical path is realized through the beam splitting module, which is beneficial to the miniaturization of the OCT probe. Moreover, after the alignment of a single optical path, the alignment of the other optical path is completed, which is beneficial to improving the optical path alignment accuracy. The fields of view and imaging regions of the OCT detection optical path and the camera module shooting optical path are consistent, facilitating image registration and synchronous display. Further, the phase of the detection beam is regulated by the diffractive optical element to emit a needle-shaped beam, which is beneficial to increasing the focal depth of the OCT probe and achieving a larger imaging range, and is beneficial to realizing high-resolution imaging of deep tissues within the same field of view compared with the traditional Gaussian beam.

[0028] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and do not limit the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings herein are incorporated into the specification and form a part of the specification, showing embodiments consistent with the present disclosure and, together with the specification, are used to explain the principles of the present disclosure.

[0030] Figure 1 is a cross-sectional schematic view of an OCT probe shown according to an exemplary embodiment.

[0031] Figure 2 is Figure 1 an exploded schematic view of the OCT probe in

[0032] Figure 3 is Figure 1 a partial schematic view of the OCT probe in

[0033] Figure 4 It is a schematic structural diagram of an imaging system shown according to an exemplary embodiment.

[0034] Figure 5 Based on Figure 4 It is a three-dimensional OCT point cloud image obtained by the imaging system in for prostate imaging.

[0035] Figure 6 Based on Figure 4 It is a surface image obtained by the imaging system in for prostate imaging. Detailed implementation manners

[0036] Here, the exemplary embodiments will be described in detail, and the examples are shown in the drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementation manners described in the following exemplary embodiments do not represent all implementation manners consistent with the present disclosure. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0037] The terms used in the present disclosure are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. The singular forms "a", "the" and "said" used in the present disclosure 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" used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0038] It should be understood that although the terms first, second, third, etc. may be used in the present disclosure to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present disclosure, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "when" or "while" or "in response to determining".

[0039] Figure 1 It is a schematic cross-sectional view of an OCT probe shown according to an exemplary embodiment. Figure 2 It is Figure 1 The exploded view of the OCT probe in Figure 3 It is Figure 1 The partial view of the OCT probe in . The OCT probe can be adapted to a surgical robot, provided with a quick-release interface, and the pose modulation and quick replacement of the OCT probe can be realized during the operation. As Figure 1 and Figure 2As shown, the OCT probe includes a single-mode optical fiber 1, an optical fiber collimator 2, a diffractive optical element 3, a MEMS (Micro-Electro-Mechanical System Micro-Scanner) micro-scanning mirror 4, a reflection component 5, a focusing lens 6, a beam splitting module 7, and a camera module 8. Among them, the optical fiber collimator 2, the diffractive optical element 3, the focusing lens 6, and the beam splitting module 7 are arranged along the axial direction of the OCT probe, that is Figure 1 As shown in, the optical fiber collimator 2, the diffractive optical element 3, the focusing lens 6, and the beam splitting module 7 are arranged in sequence from right to left. Among them, the detection beam transmitted by the single-mode optical fiber 1 can be collimated by the optical fiber collimator 2 and then incident on the diffractive optical element 3. The diffractive optical element 3 can be used to modulate the detection beam from the optical fiber collimator 2 and emit a needle-shaped beam, that is, the detection beam can be regulated into a needle-shaped beam through the diffractive optical element 3.

[0040] Both the MEMS micro-scanning mirror 4 and the reflection component 5 are arranged between the focusing lens 6 and the diffractive optical element 3. And the needle-shaped beam from the diffractive optical element 3 can be reflected by the reflection component 5 and then incident on the MEMS micro-scanning mirror 4. Further, it can be reflected by the MEMS micro-scanning mirror 4 to the focusing lens 6. The light emitted from the focusing lens 6 can be emitted parallel to the axial direction of the OCT probe after passing through the beam splitting module 7. The emitted detection beam is hit on the target tissue to obtain the internal structure information of the target tissue.

[0041] The optical axis direction of the camera module 8 can be set perpendicular to the axial direction of the OCT probe. Through the camera module 8, the image information outside the OCT probe can be obtained. For example, when the OCT probe enters the abdominal cavity through the surgical channel and reaches the target tissue, the surface image of the target tissue can be taken through the camera module 8. The reflected light from the surface of the target tissue can be incident on the beam splitting module 7 parallel to the axial direction of the OCT probe and further reflected by the beam splitting module 7 to the camera module 8 for imaging, so as to obtain the surface image of the target tissue.

[0042] In this embodiment, the beam splitting module 7 can reflect the shooting beam to the camera module 8, and at the same time allow the detection beam to transmit, realizing the coaxial and common-path design of the OCT detection optical path and the shooting optical path, which is beneficial to the miniaturization of the OCT probe. Moreover, after the alignment of a single optical path, the alignment of the other optical path is completed, which is beneficial to improving the optical path alignment accuracy. And the fields of view and imaging regions of the two are the same, which is convenient for image registration and synchronous display. Moreover, by regulating the phase of the detection beam through the diffractive optical element 3 to emit a needle-shaped beam, it is beneficial to lengthen the focal depth of the OCT probe and realize a larger imaging range, and is beneficial to realizing high-resolution imaging of deep tissues in the same field of view compared with the traditional Gaussian beam.

[0043] In some embodiments, the optical axis of the fiber collimator 2 is arranged coaxially with the OCT probe, so as to facilitate the collimated optical fiber parallel to the OCT probe to be emitted through the fiber collimator 2. Preferably, the collimation wavelength selected for the fiber collimator 2 is 1310 nm, f = 11.26 mm, NA = 0.25, where f represents the focal length and NA represents the numerical aperture. Preferably, the fiber collimator 2 is connected to the single-mode fiber 1, and the interface can be FC / APC. Through the connection between the fiber collimator 2 and the single-mode fiber 1, the fiber collimator 2 can convert the transmitted light in the single-mode fiber 1 into parallel light for emission. The fiber collimator 2 can include an aspherical lens fixed-focus fiber collimator.

[0044] In some embodiments, the diffractive optical element 3 can be a circular element, and its diameter can be in the range of 10 mm - 15 mm. For example, the diameter of the diffractive optical element 3 can be 10.8 mm, 11.2 mm, 12 mm, 12.7 mm, 13.8 mm, etc. The diffractive optical element 3 can be used to perform phase modulation on the detection beam from the fiber collimator 2, so that multiple foci are generated within the range where the focus of the self-focusing lens moves inward along the axial direction of the OCT probe. The needle-shaped beam with a long depth of focus is formed by these multiple foci, which is beneficial to the advantages of high energy utilization rate, weak side lobes, and good axial uniformity of the needle-shaped beam, and is more conducive to biological tissue imaging. After adding the diffractive optical element 3, the needle-shaped beam can maintain a spot size of less than 8 μm within the axial range of 450 μm of the OCT probe. Although the traditional Gaussian beam has a smaller spot size near the focal plane, its spot size will rapidly expand with the axial distance of the OCT probe and can only maintain a size of less than 8 μm within an axial range of 160 μm. Obviously, the depth of focus of the OCT probe can be effectively increased by this needle-shaped beam.

[0045] Furthermore, the diameter, intensity, and side lobes of the beam emitted from the diffractive optical element 3 can be adjusted by adjusting the initial phase of each focus. The beam quality of the beam emitted from the diffractive optical element 3 can be improved by optimizing the number of foci, the position of pixels, and the initial phase, and finally a needle-shaped beam that can reach 50 - 100 times the Rayleigh distance can be generated. Further, the axial intensity uniformity of the beam can be achieved and the stability of the OCT signal can be improved by optimizing the design of the DOE, such as the phase distribution, focus configuration, and structural parameters of the diffractive optical element 3.

[0046] In some embodiments, the MEMS microscanner 4 can be used to adjust the scanning angle of the light beam to achieve high-resolution imaging of tissues. The MEMS microscanner can cause the angle of the mirror surface to change by varying the driving voltage, thereby controlling the deflection direction of the incident light beam. The axis of the MEMS microscanner 4 is set at 45° to the incident light beam. The MEMS microscanner 4 is used to continuously deflect the incident light beam within a preset range to generate a continuous linear scanning light beam. For example, the diameter of the circular mirror of the MEMS microscanner 4 is preferably 3.6 mm. The MEMS microscanner 4 can be driven to deflect in two other directions perpendicular to the axis of the OCT probe, for example, the deflection angle is within the range of ±7°.

[0047] In some embodiments, the focusing lens 6 can be an achromatic focusing lens 6 to focus the light beam from the MEMS microscanner 4. Further, the diameter of the focusing lens 6 is preferably 12.7 mm, and the focal length is 19 mm. Further, the center of the focusing lens 6 can coincide with the center of the OCT probe.

[0048] In some embodiments, the beam splitting module 7 can use a dichroic mirror to split the light. For example, a long-pass dichroic mirror can be used. In this way, the OCT optical path with a longer wavelength passes through the dichroic mirror, and the camera optical path with a shorter wavelength is reflected on the surface of the dichroic mirror. The OCT optical path and the RGB camera optical path achieve coaxial common optical path through the dichroic mirror, thereby ensuring that their fields of view and imaging regions are consistent, facilitating image registration and synchronous display. Further, the size of the dichroic mirror is 15*15*1 mm. The optical axis of the dichroic mirror is set at a 45° angle to the axis of the OCT probe, which is beneficial for reflecting the reflected light beam from the surface of the target tissue into the camera module 8 set perpendicular to the axis of the OCT probe.

[0049] In some embodiments, the camera module can include a color camera module, so as to perform color imaging on the surface of the target tissue and improve the display effect. The camera module 8 can select a CMOS micro USB camera. The diameter of the camera module 8 is 7 mm, and it can provide high-definition images within a distance of 3 mm to 50 mm. The OCT probe can also include an aperture arranged on the light incident side of the camera module 8, such as an LED aperture, and the object to be measured can be illuminated through this aperture. Subsequently, the surface image of the target tissue collected by the camera module 8 and the three-dimensional OCT point cloud image collected through the OCT optical path can both be sent to the processor end. The processor end can collect the surface image of the target tissue and the three-dimensional OCT point cloud image in real time, and fuse the surface image of the target tissue and the three-dimensional OCT point cloud image through an image registration algorithm to generate a comprehensive three-dimensional point cloud image. Further, the processor can display the fused three-dimensional point cloud image on the display screen. During the operation, through the real-time update of the image, the surface area of the lesion and the microscopic structure of the tissue can be accurately observed.

[0050] Moreover, by synchronously fusing the surface image of the camera module 8 and the OCT three-dimensional OCT point cloud image, a comprehensive view from the tissue surface to the internal structure is provided, which is beneficial to obtaining more accurate information in intraoperative real-time diagnosis. Moreover, by combining the OCT three-dimensional OCT point cloud image with the surface image, the position, shape of the lesion and its relationship with the surrounding tissues can be accurately judged, so as to make more accurate diagnosis and treatment decisions.

[0051] In some embodiments, the reflection component 5 includes a first right-angle reflector 51, a second right-angle reflector 52, and a third right-angle reflector 53. The reflection surfaces of the first right-angle reflector 51, the second right-angle reflector 52, and the third right-angle reflector 53 are all at an angle of 45° to the axis of the OCT probe. For example, the first right-angle reflector 51, the second right-angle reflector 52, and the third right-angle reflector 53 can all be isosceles right-angle reflectors. In this case, one right-angled side of the isosceles right-angle reflector is perpendicular to the axis of the OCT probe, and the other right-angled side is parallel to the axis of the OCT probe. With this setting, the light rays reflected by the reflection surfaces of the first right-angle reflector 51, the second right-angle reflector 52, and the third right-angle reflector 53 are all parallel to the axis of the OCT probe or perpendicular to the axis of the OCT probe.

[0052] Based on this, the reflection surface of the first right-angle reflector 51 can be oriented towards the diffractive optical element. The needle-shaped beam is reflected by the first right-angle reflector 51 and exits perpendicular to the axis of the OCT probe to the second right-angle reflector 52. The light rays exiting from the second right-angle reflector 52 are incident on the third right-angle reflector 53 parallel to the axis of the OCT probe. The light rays exiting from the third right-angle reflector 53 are incident on the MEMS micro-scanning mirror 4 perpendicular to the axis of the OCT probe. The MEMS micro-scanning mirror 4 reflects the light rays to the focusing lens 6 for focusing. The reflection surface of the MEMS micro-scanning mirror 4 is at an angle of 45° to the axis of the OCT probe. Such a setting can make the light rays exiting from the MEMS micro-scanning mirror 4 parallel to the axis of the OCT probe.

[0053] In some embodiments, the OCT probe further includes a mounting base 9. The mounting base 9 includes a receiving cavity 91 and a groove 92 communicating with the receiving cavity 91. The focusing lens 6 is disposed on one side of the mounting base 9 facing the MEMS micro scanner. The beam splitting module 7 is disposed in the receiving cavity 91, and the camera module 8 is disposed in the groove 92. Thus, the provision of the mounting base 9 is conducive to fixing the relative positional relationship between the beam splitting module 7 and the camera module 8, ensuring that the reflected light from the tissue surface can be reflected to the image sensor of the camera module 8 through the reflection of the beam splitting module 7, which is conducive to improving the light collection amount of the camera module 8. Among them, the focusing lens 6 and the mounting base 9 can be fixed by bonding, clamping or screw connection. Similarly, the beam splitting module 7 can also be fixed by bonding, clamping or screw connection. Similarly, the camera module 8 can be fixed by bonding, clamping or screw connection. The present disclosure does not limit this.

[0054] Of course, inside the OCT probe, in order to fix the MEMS micro scanner 4 and the reflection assembly 5, the OCT probe may further include a fixing base. The fixing base and the mounting base 9 are arranged at intervals along the axial direction of the OCT probe. The MEMS micro scanner 4 and the reflection assembly 5 can both be fixed on the fixing base. For example, the MEMS micro scanner 4 can be fixed by clamping or screw connection. The first right-angle reflector 51, the second right-angle reflector 52, and the third right-angle reflector 53 included in the reflection assembly 5 can be fixed by bonding or clamping. Of course, the diffractive optical element 3 and the fiber collimator 2 can be fixed on the fixing base or can be fixed on other fixings included in the OCT probe, which will not be elaborated here one by one.

[0055] In each of the above embodiments, the OCT probe further includes a cylindrical housing 10, a cover 11, and a light-transmitting window piece 12. The cover 11 is detachably connected to the cylindrical housing 10 along the axial direction of the OCT probe, and the cylindrical housing 10 and the cover 11 can be connected to form a device cavity. The fiber collimator 2, the diffractive optical element 3, the MEMS micro scanner 4, the reflection assembly 5, the focusing lens 6, the beam splitting module 7, and the camera module 8 are all controlled and disposed in the device cavity. The single-mode optical fiber 1 can partially extend outside the cover 11. The cover 11 and the cylindrical housing 10 can be connected by threads for easy disassembly, or the cover 11 and the cylindrical housing 10 can be clamped and fixed. Among them, the inner walls of the cylindrical housing 10 and the cover 11 can be provided with an absorbent layer. For example, a black fuel can be sprayed on the inner walls to form the absorbent layer to absorb scattered light. The diameter of the cylindrical housing 10 can be less than or equal to 26 mm to achieve high integration and miniaturization of the OCT probe. The cylindrical housing 10 and the cover 11 can be prepared from biocompatible materials, such as medical titanium alloy.

[0056] The light-transmitting window piece 13 can be arranged at one end of the cylindrical housing 10 facing away from the cover body 11. The reflected optical fiber from the surface of the target tissue can enter the spectroscopic module 7 through the light-transmitting window piece 13, and the output optical fiber of the MEMS micro scanner can be output to the target tissue after passing through the spectroscopic module 7 and the light-transmitting window piece 13. The light-transmitting window piece 13 can be of any shape, such as circular, square or oval. An antireflection film is also arranged on the side of the light-transmitting window piece 13 facing away from the cylindrical housing 10 to minimize light loss as much as possible and achieve dust and water protection at the same time. The light-transmitting window piece 13 can be fixed by bonding or clamping, and the present disclosure does not limit this.

[0057] Based on the technical solution of the present disclosure, as Figure 4 shown, an imaging system is further provided. The imaging system can include a reference arm assembly 101, an optical fiber coupler 102, a light source 103, a spectrometer 104, a processor system 105, and an OCT probe as described in any one of the foregoing embodiments. The light source 103 is connected to the optical fiber coupler 102, and the optical fiber emitted by the light source can be emitted through the optical fiber coupler 102. The light source 103 can use a broadband superluminescent diode light source with a central wavelength of 1310 nm, and the output light beam enters the optical fiber coupler 102. The bandwidth of the optical fiber coupler 102 is 110 nm to ensure sufficient imaging depth and resolution.

[0058] The optical fiber coupler 102 can be a 50 / 50 single-mode optical fiber coupler. Through the optical fiber coupler 102, the light beam can be divided into two paths, one path enters the reference arm assembly 101, and the other path enters the OCT probe and enters the internal OCT optical path of the OCT probe through the single-mode optical fiber 1. The spectrometer 104 can generate an analog signal according to the interference signal formed by the light beam returned by the reference arm assembly 101 and the light beam returned by the OCT probe; the processor system 105 can generate a three-dimensional OCT point cloud image in the sample depth direction according to the analog signal generated by the spectrometer. The processor system 105 is also communicatively connected to the camera module 8. The processor system 105 is used to register the two-dimensional image information collected by the camera module 8 with the three-dimensional OCT point cloud image to obtain a fused image. During the operation, through the real-time update of the image, the surface area of the lesion and the microscopic structure of the tissue can be accurately observed.

[0059] In some embodiments, the processor system 105 may include a data acquisition card, a signal generation card, and a graphics processor. The analog signals converted by the spectrometer 104 may be transmitted to the data acquisition card and further transmitted to the graphics processor, and a three-dimensional OCT point cloud image of the target tissue in the depth direction may be generated by the graphics processor. The signal generation card may control the deflection of the MEMS micro scanner 4, and the MEMS micro scanner 4 may be controlled to perform one-dimensional scanning or two-dimensional scanning through the control signal of the signal generation card. For example, the imaging system further includes an MEMS driver board 106, and the MEMS driver board 106 is electrically connected to the signal generation card and the MEMS micro scanner respectively. For example, the MEMS driver board 106 transmits an electric control signal through a cable to control the deflection of the MEMS micro scanner 4, so that the control instruction from the signal generation card can be transmitted to the MEMS micro scanner 4 to control the MEMS micro scanner 4 to perform one-dimensional scanning or two-dimensional scanning. Among them, one-dimensional scanning can be applied to quickly obtain a three-dimensional OCT point cloud image of the target tissue, and two-dimensional scanning can be applied to generate a high-resolution three-dimensional stereoscopic image.

[0060] The spectrometer 104 may include a grating and a CCD (Charge-coupled Device) detector. After receiving the light beam returned by the reference arm assembly 101 and the light beam returned by the OCT probe, the fiber optic coupler 102 forms an interference signal and further transmits it to the spectrometer 104. The grating and CCD detector of the spectrometer 104 convert the interference signal into an analog signal and then transmit it to the processor system.

[0061] In some embodiments, due to the movement of the target tissue during breathing or due to the construction of the surgical channel, in order to better adapt to the movement of the target tissue, the processor system is further configured to extract the image edge features of two adjacent frames of three-dimensional OCT point cloud images respectively, obtain the relative position relationship between the two adjacent frames of images through the difference between the image edge features of the two frames of images, and control the movement of the OCT probe according to the relative position relationship. For example, by the difference in the image edge features of two frames of images, it is determined that the target tissue in the latter frame of three-dimensional OCT point cloud image moves 3 mm downward relative to the target tissue in the previous frame of three-dimensional OCT point cloud image. Then the processor system can control the OCT probe to move 3 mm in the same direction to ensure a stable specific distance between the OCT probe and the target tissue, which is beneficial to maintaining the quality stability of the three-dimensional OCT point cloud image, reducing the imaging error caused by breathing or surgical operations, and realizing dynamic closed-loop compensation. Among them, the movement of the OCT probe can be controlled based on a proportional-integral control algorithm. The application of this algorithm is beneficial to the movement speed of the OCT probe to adapt to the movement speed of the target tissue and the movement distance to adapt to the movement distance of the target tissue, and improves the smoothness of the movement of the OCT probe.

[0062] The latency of the real-time feedback system constructed by extracting image edge features can be less than 10 milliseconds. By controlling the movement of the OCT probe through the proportional-integral control algorithm, the tissue displacement error caused by breathing and instrument operation can be reduced. Specifically, the maximum gradient surface detection algorithm is implemented using CUDA C++ parallel computing, and real-time motion compensation is performed through PID feedback control. The maximum gradient algorithm is used to identify the tissue surface, and the B-scan calculation efficiency is optimized by combining the parallel GPU acceleration algorithm, enabling the probe to maintain stable focusing under tissue dynamic displacement. The movement of the probe along the Z-axis is adjusted through proportional-integral (PID) feedback control to ensure the stability of the OCT image quality and reduce imaging errors caused by breathing or surgical operations.

[0063] In some embodiments, the processor system can also be used to obtain Doppler blood flow information, and the Doppler blood flow information is superimposed on the fused image. That is, subsequently, a fused image of the three-dimensional OCT point cloud image, Doppler blood flow information, and the surface image of the target tissue can be obtained, forming multi-modal three-dimensional data from the tissue surface to the internal structure. Among them, the resolution of the three-dimensional OCT point cloud image can reach about 10um, the flow velocity accuracy of the Doppler blood flow information is within the range of ±0.1mm / s, and the camera module 8 can use a high-pixel camera, such as up to 2 million pixels. Among them, the processor system can obtain Doppler blood flow information based on the signal difference of the OCT probe at the same position of the tissue at different times.

[0064] For example, as Figure 5 and Figure 6 shown, when applying the OCT probe to a robot-assisted prostate cancer surgery, the OCT probe can be inserted into the internal surgical area of the human body through the established surgical channel during the operation to image the prostate. First, the MEMS microscanner can be controlled by the signal generator card of the processor system 105 to perform raster scanning in the target area of the prostate. The scanning range is 5×5mm2, and a total of 500 OCT B-scans are collected in one scan, obtaining the three-dimensional OCT point cloud image of the prostate as shown in Figure 5 . It can be seen from the three-dimensional OCT point cloud image that the pore-like structures in the prostate are clearly presented. This is also because the function of the diffractive optical element 3 optimizes the focal depth of the OCT, enabling high-resolution imaging of the target object. Even on an uneven tissue surface, continuous and clear images can still be obtained, helping the surgeon accurately identify and avoid the neurovascular bundle, thereby reducing postoperative functional damage. While obtaining the three-dimensional OCT point cloud image, the camera module 8 can capture the surface image of the prostate and further transmit it to the processor system 105 to obtain the prostate surface image diagram as shown in Figure 6 . Subsequently, the surface image diagram and the three-dimensional OCT point cloud image can be registered to obtain a fused image to assist intraoperative operations.

[0065] Other embodiments of the present disclosure will be readily apparent to those skilled in the art upon consideration of the specification and practice of the disclosure herein. The present disclosure is intended to cover any variations, uses, or adaptations of the disclosure, which follow the general principles of the disclosure and include known common general knowledge or conventional technical means in the technical field not disclosed herein. The specification and examples are only illustrative, and the true scope and spirit of the present disclosure are pointed out by the following claims.

[0066] It should be understood that the present disclosure is not limited to the exact structures described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present disclosure is only limited by the appended claims.

Claims

1. An OCT probe, characterized in that: It includes a fiber collimator, a diffractive optical element, a focusing lens and a light splitting module which are sequentially arranged along the optical axis direction of the OCT probe, wherein the diffractive optical element is used to modulate the detection light beam from the fiber collimator to emit a needle-shaped light beam; The OCT probe further includes a MEMS micro-scanning mirror, a reflection component and a camera module. The MEMS micro-scanning mirror and the reflection component are both arranged between the diffractive optical element and the focusing lens. The needle-shaped light beam is reflected by the MEMS micro-scanning mirror to the focusing lens after passing through the reflection component, and is emitted parallel to the axial direction of the OCT probe after passing through the light splitting module. The optical axis direction of the camera module is perpendicular to the axial direction of the OCT probe. After the reflected light from the target tissue is incident on the spectroscopic module parallel to the axial direction of the OCT probe, it is reflected by the spectroscopic module to the camera module.

2. The OCT probe according to claim 1, characterized in that: The reflection assembly comprises a first right-angle reflector, a second right-angle reflector and a third right-angle reflector, wherein the reflection surfaces of the first right-angle reflector, the second right-angle reflector and the third right-angle reflector are all at an angle of 45° with the axial direction of the OCT probe; The needle-shaped light beam passes through the first right-angle reflector and is emitted to the second right-angle reflector perpendicularly to the axial direction of the OCT probe. The light emitted from the second right-angle reflector is incident on the third right-angle reflector parallel to the axial direction of the OCT probe. The light emitted from the third right-angle reflector is incident on the MEMS micro-scanning mirror perpendicularly to the axial direction of the OCT probe. The reflecting surface of the MEMS micro-scanning mirror is 45° with the axial direction of the OCT probe.

3. The OCT probe according to claim 1, characterized in that: The diffractive optical element is used to perform phase modulation on the detection beam to form a needle-shaped beam, and the needle-shaped beam has a plurality of focal points within a set range from the focal point of the focusing lens in an axial direction outward from the OCT probe.

4. The OCT probe according to claim 1, characterized in that: Also includes: The mounting seat comprises a receiving cavity and a groove connected with the receiving cavity, the focusing lens is arranged on a side of the mounting seat facing the MEMS micro-scanning mirror, the spectrometer module is fixedly arranged in the mounting seat, and the camera module is fixedly arranged in the groove.

5. The OCT probe according to claim 1, characterized in that: Also includes: Cylindrical housing; A cover body, wherein the cover body and the cylindrical shell are detachably connected along the axial direction of the OCT probe, and the cover body and the cylindrical shell are connected to form a device cavity; A light-transmitting window sheet is arranged at an end of the cylindrical shell away from the cover body.

6. The OCT probe according to claim 1, characterized in that: It also includes an aperture arranged on the light incident side of the camera module.

7. An imaging system, characterized in that: include: The OCT probe according to any one of claims 1 to 6; Reference arm assembly; Fiber optic couplers; A light source, wherein an output light beam of the light source enters the optical fiber coupler, and partially enters the reference arm assembly and partially enters the OCT probe after passing through the optical fiber coupler; a spectrometer, wherein the spectrometer generates an analog signal according to an interference signal formed by the light beam returned by the reference arm assembly and the light beam returned by the OCT probe; A processor system, wherein the processor system generates a three-dimensional OCT point cloud image of the target tissue in the depth direction according to the analog signal, and the processor system is also communicatively connected to the camera module, and the processor system is used to align the three-dimensional OCT point cloud image with the two-dimensional image information collected by the camera module to obtain a fused image.

8. The imaging system according to claim 7, characterized in that: The processor system is also used to obtain Doppler blood flow information and superimpose the Doppler blood flow information on the fused image.

9. The imaging system according to claim 7, characterized in that: The processor system is also used to extract image edge features of two adjacent frames of the three-dimensional OCT point cloud images respectively, and obtain the relative position relationship between the two adjacent frames of the three-dimensional OCT point cloud images based on the difference between the image edge features of the two adjacent frames of the three-dimensional OCT point cloud images; and control the movement of the OCT probe based on the relative position relationship.

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