CN120203516B

CN120203516B - OCT probe and imaging system

Info

Publication number: CN120203516B
Application number: CN202510344747.7A
Authority: CN
Inventors: 孙利群; 李晓晨
Original assignee: Tsinghua University
Current assignee: Tsinghua University
Priority date: 2025-03-21
Filing date: 2025-03-21
Publication date: 2025-11-11
Anticipated expiration: 2045-03-21
Also published as: CN120203516A

Abstract

This disclosure relates to an OCT probe and imaging system. The OCT probe includes an optical fiber collimator, a diffractive optical element, a focusing lens, and a beam splitter arranged sequentially along the optical axis of the OCT probe. The diffractive optical element is used to modulate the probe beam from the optical fiber collimator to emit a needle-shaped beam. The OCT probe also includes a MEMS micro-scanning mirror, a reflective component, and a camera module. The MEMS micro-scanning mirror and the reflective component are both disposed between the diffractive optical element and the focusing lens. The needle-shaped beam is reflected by the MEMS micro-scanning mirror to the focusing lens after passing through the reflective component, and then emitted parallel to the axial direction of the OCT probe after passing through the beam splitter. The optical axis of the camera module is perpendicular to the axial direction of the OCT probe. Reflected light from the target tissue is incident parallel to the axial direction of the OCT probe onto the beam splitter and then reflected by the beam splitter to the camera module.

Description

OCT probe and imaging system

Technical Field

The present disclosure relates to the field of terminal technologies, and in particular, to an OCT probe and an imaging system.

Background

Conventional OCT (Optical Coherence Tomography ) is widely used for in vivo tissue imaging as a non-invasive, biomedical imaging technique. However, the existing OCT probe can only acquire internal information of a tissue, cannot acquire the influence of the surface of the tissue, and the probe beam of the conventional OCT probe is a gaussian beam, so that a thicker tissue layer is difficult to cover in the operation process, and information of a deep structure in an image is easy to be lost.

Disclosure of Invention

The present disclosure provides an OCT probe and imaging system to address deficiencies in the related art.

According to a first aspect of embodiments of the present disclosure, there is provided an OCT probe including an optical fiber collimator, a diffractive optical element, a focusing lens, and a spectroscopic module, which are sequentially arranged in an optical axis direction of the OCT probe, the diffractive optical element being configured to modulate a probe beam from the optical fiber collimator to emit a needle-like beam;

The OCT probe also comprises an MEMS micro-scanning mirror, a reflecting component and a camera module, wherein the MEMS micro-scanning mirror and the reflecting component are arranged between the diffraction 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 reflecting component and is axially emergent parallel to 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 the reflected light from the target tissue is parallel to the axial direction of the OCT probe and then is reflected to the camera module by the light splitting module after entering the light splitting module.

Optionally, the reflecting component includes a first right-angle reflector, a second right-angle reflector, and a third right-angle reflector, where reflecting surfaces of the first right-angle reflector, the second right-angle reflector, and the third right-angle reflector form an included angle of 45 ° with an axial direction of the OCT probe;

The needle-shaped light beam axially exits to the second right-angle reflecting mirror perpendicular to the OCT probe after passing through the first right-angle reflecting mirror, the light rays exiting from the second right-angle reflecting mirror are parallel to the OCT probe and axially enter to the third right-angle reflecting mirror, the light rays exiting from the third right-angle reflecting mirror are axially enter to the MEMS micro-scanning mirror perpendicular to the OCT probe, and the reflecting surface of the MEMS micro-scanning mirror and the OCT probe axially form 45 degrees.

Optionally, the diffractive optical element is configured to phase modulate the probe beam to form a needle beam, where the needle beam has a plurality of focuses within a set range along an axially outward direction of the OCT probe from a focus of the focusing lens.

Optionally, the method further comprises:

The mounting seat comprises a containing cavity and a groove communicated with the containing cavity, the focusing lens is arranged on one side, facing the MEMS micro-scanning mirror, of the mounting seat, the light splitting module is fixedly arranged in the mounting seat, and the camera module is fixedly arranged in the groove.

Optionally, the method further comprises:

A cylindrical housing;

the cover body is detachably connected with the cylindrical shell along the axial direction of the OCT probe, and the cover body is connected with the cylindrical shell to form a device cavity;

the light-transmitting window sheet is arranged at one end of the cylindrical shell, which is away from the cover body.

Optionally, the camera module further comprises an aperture arranged on the light incident side of the camera module.

According to a second aspect of embodiments of the present disclosure, there is provided an imaging system comprising:

The OCT probe of any one of the previous embodiments;

A reference arm assembly;

An optical fiber coupler;

a light source, wherein an output light beam of the light source enters the optical fiber coupler, and enters the reference arm assembly partially through the rear part of the optical fiber coupler and enters the OCT probe partially;

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;

The processor system is used for generating a three-dimensional OCT point cloud image of the target tissue in the depth direction according to the analog signals, the processor system is also in communication connection with the camera module, and the processor system is used for registering the three-dimensional OCT point cloud image according to the two-dimensional image information acquired by the camera module to obtain a fusion image.

Optionally, the processor system is further configured to acquire doppler blood flow information, and superimpose the doppler blood flow information on the fused image.

Optionally, the processor system is further configured to extract image edge features of two adjacent frames of the three-dimensional OCT point cloud images, obtain a relative positional relationship between the two adjacent frames of three-dimensional OCT point cloud images according to a difference between the image edge features of the two adjacent frames of three-dimensional OCT point cloud images, and control the OCT probe to move according to the relative positional relationship.

The technical scheme provided by the embodiment of the disclosure can comprise the following beneficial effects:

According to the embodiment, the coaxial common-path design of the OCT detection light path and the camera module shooting light path is realized through the light splitting module, miniaturization of the OCT probe is facilitated, alignment of another light path is completed after alignment of a single light path, alignment precision of the light path is improved, visual fields and imaging areas of the OCT detection light path and the camera module shooting light path are consistent, image registration and synchronous display are facilitated, furthermore, phase adjustment of the detection light beam is conducted through the diffraction optical element to emit needle-shaped light beams, focal depth of the OCT probe is facilitated to be prolonged, a larger imaging range is achieved, and deep tissue high-resolution imaging in the same visual field is facilitated compared with that of a traditional Gaussian light beam.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the disclosure and together with the description, serve to explain the principles of the disclosure.

Fig. 1 is a schematic cross-sectional view of an OCT probe, according to an example embodiment.

Fig. 2 is an exploded schematic view of the OCT probe of fig. 1.

Fig. 3 is a partial schematic view of the OCT probe of fig. 1.

Fig. 4 is a schematic diagram illustrating a configuration of an imaging system according to an exemplary embodiment.

Fig. 5 is a three-dimensional OCT point cloud image based on the imaging system of fig. 4 to image the prostate.

Fig. 6 is a surface image of a prostate imaged based on the imaging system of fig. 4.

Detailed Description

Reference will now be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, the same numbers in different drawings refer to the same or similar elements, unless otherwise indicated. The implementations described in the following exemplary examples are not representative of all implementations consistent with the present disclosure. Rather, they are merely examples of apparatus and methods consistent with some aspects of the present disclosure as detailed in the accompanying claims.

The terminology used in the present disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used in this disclosure and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any or all possible combinations of one or more of the associated listed items.

It should be understood that although the terms first, second, third, etc. may be used in this disclosure to describe various information, these information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information, without departing from the scope of the present disclosure. The term "if" as used herein may be interpreted as "at..once" or "when..once" or "in response to a determination", depending on the context.

Fig. 1 is a schematic cross-sectional view of an OCT probe according to an exemplary embodiment, fig. 2 is an exploded schematic view of the OCT probe of fig. 1, and fig. 3 is a partial schematic view of the OCT probe of fig. 1. The OCT probe can be matched with a surgical robot, a quick-release interface is arranged, and the pose modulation and the quick replacement of the OCT probe are realized in the surgical process. As shown in fig. 1 and 2, the OCT probe includes a single-mode fiber 1, a fiber collimator 2, a diffractive optical element 3, a MEMS (Micro-Electro-MECHANICAL SYSTEM Micro-Scanner, micro-electromechanical system Micro-Scanner) Micro-Scanner 4, a reflection assembly 5, a focus lens 6, a spectroscopic module 7, and a camera module 8. The optical fiber collimator 2, the diffractive optical element 3, the focusing lens 6 and the spectroscopic module 7 are disposed along the axial direction of the OCT probe, that is, the optical fiber collimator 2, the diffractive optical element 3, the focusing lens 6 and the spectroscopic module 7 are disposed in this order from right to left as shown in fig. 1. The probe beam transmitted by the single-mode fiber 1 may be collimated by the fiber collimator 2 and then enter the diffractive optical element 3, where the diffractive optical element 3 may be used to modulate the probe beam from the fiber collimator 2 and emit a needle beam, that is, the probe beam may be regulated to be a needle beam by the diffractive optical element 3.

The MEMS micro-scanning mirror 4 and the reflecting component 5 are both disposed between the focusing lens 6 and the diffractive optical element 3, and the needle-shaped light beam from the diffractive optical element 3 can be incident on the MEMS micro-scanning mirror 4 after being reflected by the reflecting component 5, and further can be reflected to the focusing lens 6 by the MEMS micro-scanning mirror 4, the light beam exiting from the focusing lens 6 can be axially exiting parallel to the OCT probe after passing through the beam splitting module 7, and the exiting probe light beam is beaten onto the target tissue to obtain the internal structural information of the target tissue.

The optical axis direction of the camera module 8 may be arranged perpendicular to the axial direction of the OCT probe, and image information of the outside of the OCT probe may be acquired by the camera module 8, for example, when the OCT probe reaches the target tissue through the inside of the abdominal cavity through the surgical channel, a surface image of the target tissue may be photographed by the camera module 8. The reflected light from the surface of the target tissue can be axially incident on the beam splitting module 7 parallel to the OCT probe, and further reflected to the camera module 8 for imaging through the beam splitting module 7, so as to acquire the surface image of the target tissue.

In this embodiment, the beam splitting module 7 can reflect the shooting beam to the camera module 8, and can allow the transmission of the detection beam, so that the coaxial common-path design of the OCT detection light path and the shooting light path is realized, which is beneficial to miniaturization of the OCT probe, and alignment of another light path is completed after alignment of a single light path, which is beneficial to improving the alignment accuracy of the light paths, and the fields of view and the imaging areas of the two are consistent, so that the image registration and synchronous display are facilitated. And the phase of the detection light beam is regulated and controlled by the diffraction optical element 3 to emit a needle-shaped light beam, so that the focal depth of the OCT probe is prolonged, a larger imaging range is realized, and the high-resolution imaging of deep tissues in the same view field is realized compared with the traditional Gaussian light beam.

In some embodiments, the optical axis of the fiber collimator 2 is arranged along the axis of the OCT probe, so that a collimated fiber parallel to the OCT probe can be emitted through the fiber collimator 2. Preferably, the optical fiber collimator 2 adopts a collimation wavelength of 1310nm, f=11.26mm and na=0.25, wherein f represents a focal length and NA represents a numerical aperture. Preferably, the fiber collimator 2 is connected with the single-mode fiber 1, and the interface can be FC/APC. Through the connection of the optical fiber collimator 2 and the single-mode optical fiber 1, the optical fiber collimator 2 can convert the transmission light in the single-mode optical fiber 1 into parallel light and emit the parallel light. The fiber collimator 2 may comprise an aspherical lens surface Jiao Guangqian collimator.

In some embodiments, the diffractive optical element 3 may be a circular element, which may be in the range of 10mm-15mm in diameter, for example the diffractive optical element 3 may be 10.8mm, 11.2mm, 12mm, 12.7mm, 13.8mm, etc. The diffraction optical element 3 can be used for carrying out phase modulation on the detection light beam from the optical fiber collimator 2, so that a plurality of focuses are generated in the range of the focus of the self-focusing lens along the axial inward direction of the OCT probe, and the plurality of focuses form a needle-shaped light beam with long focal depth, thereby being beneficial to the advantages of high energy utilization rate, weak side lobe, good axial uniformity and the like of the needle-shaped light beam and being more beneficial to biological tissue imaging. The needle beam formed by adding the diffractive optical element 3 can keep the spot size smaller than 8 μm in the axial range of the OCT probe of 450 μm, while the conventional gaussian beam has smaller spot size near the focal plane, but the spot size can be rapidly enlarged along with the axial distance of the OCT probe, and can only keep smaller than 8 μm in the axial range of 160 μm. Obviously, the focal depth of the OCT probe can be effectively increased by the needle beam.

Further, the diameter, intensity, and side lobes of the light beam exiting from the diffractive optical element 3 can be adjusted by adjusting the initial phase of each focal point. The quality of the beam exiting from the diffractive optical element 3 is improved by optimizing the number of focal points, the positions of the pixels, the initial phase, and finally a needle-shaped beam capable of reaching 50-100 rayleigh distances is generated. The axial intensity uniformity of the light beam can be further achieved by optimizing the DOE design, such as the phase distribution, focal point configuration and structural parameters of the diffractive optical element 3, to improve the stability of the OCT signal.

In some embodiments, the MEMS micro-scanning mirror 4 may be used to adjust the scanning angle of the light beam to achieve high resolution imaging of tissue. The MEMS micro-scanning mirror can control the deflection direction of an incident beam by causing an angular change of the mirror surface by a change in driving voltage. The MEMS micro-scanning mirror 4 is disposed at 45 ° to the incident beam, and the MEMS micro-scanning mirror 4 is configured to continuously deflect the incident beam within a predetermined range to generate a continuous linear scanning beam. For example, the circular mirror diameter of the MEMS micro-scanning mirror 4 is preferably 3.6mm. The MEMS micro-scanning mirror 4 can be deflected separately by driving in other two directions perpendicular to the OCT probe axis, for example, the deflection angle is within ±7°.

In some embodiments, focusing lens 6 may employ an achromatic focusing lens 6 to focus the beam from MEMS micro-scanning mirror 4. Further, the diameter of the focusing lens 6 is preferably 12.7mm. The focal length is 19mm. Further, the focus lens 6 center may coincide with the center of the OCT probe.

In some embodiments, the beam splitting module 7 may employ a dichroic mirror to split the beam, for example, a long-pass dichroic mirror may be employed, whereby the longer wavelength OCT optical path is transmitted through the dichroic mirror and the shorter wavelength camera optical path is reflected at the dichroic mirror surface. The OCT light path and the RGB camera light path realize coaxial common light path through the dichroic mirror, thereby ensuring the consistent view field and imaging area of the OCT light path and the RGB camera, and facilitating image registration and synchronous display. Further, the dichroic mirror size is 15×15×1mm. The optical axis of the dichroic mirror is disposed at an angle of 45 ° to the OCT probe axis, thereby facilitating reflection of the reflected beam from the target tissue surface into the camera module 8 disposed perpendicularly to the OCT probe axis.

In some embodiments, the camera module may include a color camera module, so that the target tissue surface may be color imaged, enhancing the display effect. The camera module 8 may be a CMOS micro USB camera, and the camera module 8 may have a diameter of 7mm and may provide high definition images within a distance of 3mm to 50 mm. The OCT probe may also comprise an aperture, for example an LED aperture, arranged on the light entry side of the camera module 8, through which the object to be measured can be illuminated. The surface image of the target tissue collected by the camera module 8 and the OCT three-dimensional OCT point cloud image collected by the OCT light path can be sent to a processor end, the surface image of the target tissue and the three-dimensional OCT point cloud image can be collected in real time by the processor end, the surface image of the target tissue and the three-dimensional OCT point cloud image are fused by an image registration algorithm to generate a comprehensive three-dimensional point cloud image, the fused three-dimensional point cloud image can be further displayed on a display screen by the processor, and the pathological change surface area and the surrounding structure of the tissue can be accurately observed by the real-time updating of the image in operation.

And the surface image of the camera module 8 and the OCT three-dimensional OCT point cloud image are synchronously fused, so that a comprehensive view from the surface of the tissue to the internal structure is provided, more accurate information can be acquired in real-time diagnosis in operation, and the position, the shape and the relation between the focus and surrounding tissues can be accurately judged by combining the OCT three-dimensional OCT point cloud image and the surface image, so that more accurate diagnosis and treatment decisions can be made.

In some embodiments, the reflecting assembly 5 comprises a first right angle mirror 51, a second right angle mirror 52, and a third right angle mirror 53, the reflecting surfaces of the first right angle mirror 51, the second right angle mirror 52, and the third right angle mirror 53 each being at a 45 ° angle to the axial direction of the OCT probe. For example, the first right-angle reflecting mirror 51, the second right-angle reflecting mirror 52 and the third right-angle reflecting mirror 53 may be isosceles right-angle reflecting mirrors, and then one right-angle side of the isosceles right-angle reflecting mirrors is disposed perpendicular to the OCT probe axis, and one right-angle side is disposed parallel to the OCT probe axis, so that the light reflected by the reflecting surfaces of the first right-angle reflecting mirror 51, the second right-angle reflecting mirror 52 and the third right-angle reflecting mirror 53 is parallel to the OCT probe axis or perpendicular to the OCT probe axis.

Based on this, the reflecting surface of the first right-angle reflecting mirror 51 may be disposed towards the diffractive optical element, the needle-shaped light beam is reflected by the first right-angle reflecting mirror 51 and then exits perpendicularly to the OCT probe axis to the second right-angle reflecting mirror 52, the light exiting from the second right-angle reflecting mirror 52 is parallel to the OCT probe axis and enters the third right-angle reflecting mirror 53, the light exiting from the third right-angle reflecting mirror 53 is perpendicularly to the OCT probe axis and enters the MEMS micro-scanning mirror 4, and the light is reflected to the focusing lens 6 by the MEMS micro-scanning mirror 4 for focusing. The reflecting surface of the MEMS micro-scanning mirror 4 forms an angle of 45 ° with the OCT probe axis, so that the light emitted from the MEMS micro-scanning mirror 4 is parallel to the OCT probe axis.

In some embodiments, the OCT probe further includes a mount 9, the mount 9 includes a receiving cavity 91 and a groove 92 in communication with the receiving cavity 91, the focusing lens 6 is disposed on a side of the mount 9 facing the MEMS micro-scanning mirror, the spectroscopic module 7 is disposed in the receiving cavity 91, and the camera module 8 is disposed in the groove 92. In this way, the relative positional relationship between the light splitting module 7 and the camera module 8 is fixed by the arrangement of the mounting seat 9, so that the reflected light from the tissue surface can be reflected to the image sensor of the camera module 8 through the reflection action of the light splitting module 7, and the light-collecting amount of the camera module 8 is improved. The focusing lens 6 and the mounting base 9 may be fixed by an adhesive, a clamping or a screw connection, similarly, the beam splitting module 7 may be fixed by an adhesive, a clamping or a screw connection, and similarly, the camera module 8 may be fixed by an adhesive, a clamping or a screw connection, which is not limited in the disclosure.

Of course, in this OCT probe, in order to fix the MEMS micro-scanning mirror 4 and the reflection component 5, the OCT probe may further include a fixing base, where the fixing base and the mounting base 9 are axially spaced along the OCT probe, and both the MEMS micro-scanning mirror 4 and the reflection component 5 may be fixed on the fixing base, for example, the MEMS micro-scanning mirror 4 may be fixed by a fastening or screw connection manner, and the first right-angle mirror 51, the second right-angle mirror 52 and the third right-angle mirror 53 included in the reflection component 5 may be fixed by an adhesive or fastening manner, and of course, the diffractive optical element 3 and the optical fiber collimator 2 may be fixed on the fixing base, or may be fixed on other fixing manners included in the OCT probe, which will not be repeated herein.

In the above embodiments, the OCT probe further includes the cylindrical housing 10, the cover 11 and the light-transmitting window 12, the cover 11 and the cylindrical housing 10 are detachably connected along the OCT probe axial direction, and the cylindrical housing 10 and the cover 11 may be connected to form a device cavity, in which the fiber collimator 2, the diffractive optical element 3, the MEMS micro-scanning mirror 4, the reflection assembly 5, the focusing lens 6, the spectroscopic module 7 and the camera module 8 arms control are disposed, and the single-mode fiber 1 may be partially extended through the cover 11. The cover 11 and the cylindrical shell 10 can be connected through threads so as to be convenient to detach, or the cover 11 and the cylindrical shell 10 can be clamped and fixed. Wherein the inner walls of the cylindrical housing 10 and the cover 11 may be provided with a light absorbing layer, for example, black fuel may be injected at the inner walls, thereby forming the light absorbing layer to absorb scattered light. The diameter of the cylindrical housing 10 may be less than or equal to 26mm, enabling high integration and miniaturization of the OCT probe. The cylindrical housing 10 and the cover 11 may be made of a biocompatible material, such as medical titanium alloy.

The light-transmitting window sheet 13 may be disposed at one end of the cylindrical housing 10 facing away from the cover 11, the reflective optical fiber from the surface of the target tissue may be incident to the spectroscopic module 7 through the light-transmitting window sheet 13, and the outgoing optical fiber of the mems micro-scanning mirror may be emitted to the target tissue after passing through the spectroscopic module 7 and the light-transmitting window sheet 13. The light-transmitting window piece 13 can be in any shape, such as a round shape, a square shape or an oval shape, and an antireflection film is arranged on one side of the light-transmitting window piece 13 away from the cylindrical shell 10 so as to reduce light loss as much as possible, and meanwhile, dust-proof and waterproof protection is realized. The light-transmitting window sheet 13 may be fixed by bonding or clamping, which is not limited by the present disclosure.

In accordance with aspects of the present disclosure, as shown in fig. 4, there is also provided an imaging system that may include a reference arm assembly 101, a fiber optic coupler 102, a light source 103, a spectrometer 104, a processor system 105, and an OCT probe as described in any of the foregoing embodiments. The light source 103 is connected to the optical fiber coupler 102, and the optical fiber emitted from the light source can be emitted through the optical fiber coupler 102. The light source 103 can use a broadband super-radiation diode light source with a center wavelength of 1310nm, the output light beam enters the optical fiber coupler 102, and the bandwidth of the optical fiber coupler 102 is 110nm so as to ensure enough imaging depth and resolution

The fiber coupler 102 may be a 50/50 single mode fiber coupler, through which the optical beam may be split into two paths, one of which enters the reference arm assembly 101 and the other of which enters the OCT probe and enters the internal OCT optical path of the OCT probe through the single mode fiber 1. The spectrometer 104 can generate an analog signal according to an interference signal formed by a light beam returned by the reference arm assembly 101 and a light beam returned by the OCT probe, the processor system 105 can generate a three-dimensional OCT point cloud image in the depth direction of a sample according to the analog signal generated by the spectrometer, the processor system 105 is also in communication connection with the camera module 8, the processor system 105 is used for registering with the three-dimensional OCT point cloud image according to two-dimensional image information acquired by the camera module 8 to obtain a fused image, and the microstructure of a plurality of pathological change surface areas and tissues can be accurately observed through real-time updating of the image in operation.

In some embodiments, the processor system 105 may include a data acquisition card, a signal generation card, and a graphics processor, and the analog signals converted by the spectrometer 104 may be transmitted to the data acquisition card, further transmitted to the graphics processor, through which a three-dimensional OCT point cloud image of the target tissue in the depth direction is generated. The signal generating card can control the deflection of the MEMS micro-scanning mirror 4, and the control signal of the signal generating card controls the MEMS micro-scanning mirror 4 to perform one-dimensional scanning or two-dimensional scanning. For example, the imaging system further includes a MEMS driving board 106, where the MEMS driving board 106 is electrically connected to the signal generating card and the MEMS micro-scanning mirror, for example, the MEMS driving board 106 transmits an electric control signal through a cable line to control the deflection of the MEMS micro-scanning mirror 4, so that a control instruction from the signal generating card can be transmitted to the MEMS micro-scanning mirror 4 to control the MEMS micro-scanning mirror 4 to perform one-dimensional scanning or two-dimensional scanning. Wherein the one-dimensional scanning can be applied to rapidly acquiring a three-dimensional OCT point cloud image of the target tissue, and the two-dimensional scanning can be applied to generating a high-resolution three-dimensional stereo image.

Spectrometer 104 may include a grating and CCD (Charge-coupled Device) detector, and fiber optic coupler 102 forms an interference signal after receiving the beam returned by reference arm assembly 101 and the beam returned by the OCT probe, and further transmits the interference signal to spectrometer 104, and the grating and CCD detector of spectrometer 104 converts the interference signal into an analog signal and transmits the analog signal to the processor system.

In some embodiments, the processor system is further configured to extract image edge features of two adjacent frames of three-dimensional OCT point cloud images, respectively, due to movement of the target tissue during breathing or due to construction of the surgical channel, and to obtain a relative positional relationship between the two adjacent frames of images from differences between the image edge features of the two frames of images, and to control OCT probe movement according to the relative positional relationship. For example, when it is determined that the target tissue in the three-dimensional OCT point cloud image of the subsequent frame moves 3mm below the body relative to the target tissue in the three-dimensional OCT point cloud image of the previous frame through the difference of the image edge characteristics of the two frames of images, the processor system may control the OCT probe to move 3mm in the same direction, so as to ensure that a stable specific distance between the OCT probe and the target tissue is maintained, thereby being beneficial to maintaining the quality stability of the three-dimensional OCT point cloud image, reducing the imaging error caused by respiration or operation, and realizing dynamic closed loop compensation. The movement of the OCT probe can be controlled based on a proportional integral control algorithm, the movement speed of the OCT probe is favorably adapted to the movement speed of the target tissue, the movement distance of the OCT probe is adapted to the movement distance of the target tissue through the application of the algorithm, and the smoothness of the movement of the OCT probe is improved.

The delay of the real-time feedback system constructed by image edge feature extraction can be less than 10 milliseconds, and the movement of the OCT probe is controlled by a proportional-integral control algorithm, so that the tissue displacement errors caused by respiration and instrument operation can be reduced. Specifically, a maximum gradient surface detection algorithm is realized by CUDA C++ parallel calculation, and real-time motion compensation is performed through PID feedback control. And identifying the tissue surface by adopting a maximum gradient algorithm, and optimizing the B-scan calculation efficiency by combining a parallel GPU acceleration algorithm, so that the probe can keep stable focusing under the tissue dynamic displacement. The Z-axis motion of the probe is regulated through Proportional Integral (PID) feedback control, so that the stability of OCT image quality is ensured, and imaging errors caused by breathing or operation are reduced.

In some embodiments, the processor system may also be configured to acquire doppler flow information and superimpose the doppler flow information in a fused image, i.e., a fused image of the three-dimensional OCT point cloud image, the doppler flow information, and the surface image of the target tissue may be acquired later, forming multi-modal three-dimensional data from the tissue surface to the internal structure. The resolution of the three-dimensional OCT point cloud image may reach about 10um, and the flow velocity accuracy of the doppler blood flow information may be within a range of ±0.1mm/s, and the camera module 8 may use a high-pixel camera, for example, may reach 200 ten thousand pixels. The processor system can acquire Doppler blood flow information according to signal differences of the OCT probe at different times aiming at the same position of the tissue.

For example, as shown in fig. 5 and 6, to apply the OCT probe to a robotic-assisted prostate cancer treatment procedure, the OCT probe can be advanced intra-operatively through an established operative corridor into an internal surgical field of the human body to image the prostate. Firstly, the signal generating card of the processor system 105 can control the MEMS micro scanning mirror to perform raster scanning on a target area of the prostate, the scanning range is 5×5mm2, 500 OCT B-scan is acquired for one time, a three-dimensional OCT point cloud image of the prostate is obtained, as shown in fig. 5, the three-dimensional OCT point cloud image can show that the porous structure in the prostate is clearly represented, the focal depth of the OCT is optimized due to the action of the diffraction optical element 3, a target object can be imaged with high resolution, continuous and clear images can be obtained even on uneven tissue surfaces, and the method helps an operator to accurately identify and avoid neurovascular bundles, so that the postoperative functional damage is reduced. While acquiring the three-dimensional OCT point cloud image, the camera module 8 may capture a surface image of the prostate and further transmit to the processor system 105 to obtain a surface image of the prostate shown in fig. 6, which may then be registered with the three-dimensional OCT point cloud image to obtain a fused image, assisting in the intraoperative procedure.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This disclosure is intended to cover any adaptations, uses, or adaptations of the disclosure following the general principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

It is to be understood that the present disclosure is not limited to the precise arrangements and instrumentalities shown in the drawings, and that various modifications and changes may be effected without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. An OCT probe, comprising an optical fiber collimator, a diffractive optical element, a focusing lens, and a spectroscopic module sequentially arranged along an optical axis direction of the OCT probe, wherein the diffractive optical element is used for modulating a probe beam from the optical fiber collimator to emit a needle-shaped beam;

The optical axis direction of the camera module is perpendicular to the axial direction of the OCT probe, and after the reflected light from the target tissue is parallel to the axial direction of the OCT probe and enters the beam splitting module, the reflected light is reflected to the camera module by the beam splitting module;

The reflection assembly comprises a first right-angle reflector, a second right-angle reflector and a third right-angle reflector, and the reflection surfaces of the first right-angle reflector, the second right-angle reflector and the third right-angle reflector form an included angle of 45 degrees with the axial direction of the OCT probe;

2. The OCT probe of claim 1, wherein the diffractive optical element is configured to phase modulate the probe beam to form a needle beam having a plurality of focal points within a set range in an axially outward direction of the OCT probe from a focal point of the focusing lens.

3. The OCT probe of claim 1, further comprising:

4. The OCT probe of claim 1, further comprising:

A cylindrical housing;

5. The OCT probe of claim 1, further comprising an aperture disposed on an entrance side of the camera module.

6. An imaging system, comprising:

The OCT probe of any one of claims 1-5;

A reference arm assembly;

An optical fiber coupler;

7. The imaging system of claim 6, wherein the processor system is further configured to acquire doppler flow information and superimpose the doppler flow information on the fused image.

8. The imaging system of claim 6, wherein the processor system is further configured to extract image edge features of two adjacent frames of the three-dimensional OCT point cloud images, obtain a relative positional relationship between the two adjacent frames of three-dimensional OCT point cloud images based on a difference between the image edge features of the two adjacent frames of three-dimensional OCT point cloud images, and control the OCT probe to move based on the relative positional relationship.