Composite optical fiber probe integrated with electrode array and preparation method of composite optical fiber probe

Abstract

The invention discloses a composite optical fiber probe of an integrated electrode array and a preparation method of the composite optical fiber probe, and relates to the technical field of photoelectron, and the composite optical fiber probe of the integrated electrode array comprises an optical fiber matrix, a microchannel array, a metal microwire array and a packaging layer. The micro-channel array comprises at least one groove, and each groove is formed in an external cladding of the optical fiber substrate; the metal microwire array comprises at least one metal microwire, and the metal microwires are embedded into the grooves of the microchannel array respectively; the packaging layer is filled in the groove, the metal microfilament is embedded and fixed in the groove, and the packaging layer and the outer surface of the external cladding form a continuous integral surface. According to the composite optical fiber probe integrated with the electrode array, compatibility of the quartz-based optical fiber and the metal electrode array material, flexible layout of the electrodes and customizable integration are achieved, the excellent optical transmission performance of the quartz-based hollow-core optical fiber is utilized, diversified optical signal modes are supported, and high-precision volume illumination control can be achieved.

Description

Technical Field

[0001] The present invention relates to the field of optoelectronic technology, and in particular to a composite optical fiber probe with an integrated electrode array and a preparation method thereof. Background Art

[0002] Optogenetics uses genetic engineering to make neurons express light-sensitive proteins, then uses specific wavelengths of light to precisely stimulate or inhibit their activity. The technology relies on functional neural probes that can simultaneously transmit light and record electrophysiological signals.

[0003] Currently, mainstream multifunctional neural probes are mainly realized through the following methods: Mechanical bundling: A single optical fiber for light transmission and several metal microwires (such as platinum or tungsten) for recording electrical signals are mechanically bundled together to form a probe bundle. This is the simplest and most direct method, but its disadvantages include large overall size (typically millimeter-level), low integration density, significant brain tissue trauma during implantation, and difficulty in precisely controlling the relative positions of the various functional units.

[0004] Integrated hot-stretching method: This method designs a macroscopic preform containing multiple materials and draws them at high temperatures into micron-scale multifunctional fibers that integrate conductive polymer / metal electrodes and polymer waveguides. This method has a high degree of integration and can achieve mass production of probes. However, this method has a core limitation: all materials in the preform (such as waveguide materials, electrode materials, cladding materials) must have similar thermodynamic and rheological properties (such as glass transition temperature, melting point, viscosity, etc.) in order to be successfully stretched under the same process conditions. As a result, the optical waveguide portion of such probes can usually only use polymer materials with relatively poor optical properties, and it is difficult to integrate quartz-based optical fibers with the best optical performance because the processing temperature of quartz (~2000°C) is much higher than the melting point or decomposition temperature of polymers and most metals, resulting in material incompatibility.

[0005] Quartz-based microelectrode arrays: These probes utilize semiconductor photolithography to create a high-density electrode array on a quartz substrate. These probes may also incorporate optical waveguides or micro-LEDs. While they offer excellent electrical signal recording performance, they are typically rigid, creating a mechanical mismatch with soft brain tissue. Furthermore, their fabrication process is complex and costly. Summary of the Invention

[0006] In view of this, the present invention provides a composite optical fiber probe with an integrated electrode array and a preparation method thereof, the main purpose of which is to solve the current problems of large size and high customization cost of composite optical fiber probes.

[0007] To solve the above problems, the present application provides a composite optical fiber probe with an integrated electrode array, comprising: an optical fiber substrate, a microchannel array, a metal microwire array, and an encapsulation layer; The microchannel array comprises at least one groove, each of which is arranged on the outer cladding of the optical fiber substrate; The metal microwire array includes at least one metal microwire, and each of the metal microwires is embedded in the groove of the microchannel array; The packaging layer fills the groove, embeds and fixes the metal microwires in the groove, and forms a continuous integral surface with the outer surface of the outer cladding layer.

[0008] Optionally, the optical fiber matrix is ​​a hollow-core microstructure optical fiber, comprising a hollow core, a microstructure cladding arranged around the core, and the outer cladding located outside the microstructure cladding; The microstructure cladding comprises a plurality of hollow capillary pores for guiding light, which are arranged around the fiber core and do not contact each other, and the plurality of hollow capillary pores form an anti-resonance light guiding structure; The optical fiber matrix is ​​used to transmit optical signals along the axis of the fiber core.

[0009] Optionally, the depth of the grooves of the microchannel array is less than the thickness of the outer cladding; The groove does not penetrate the microstructure cladding of the optical fiber matrix and the core of the optical fiber matrix.

[0010] Optionally, the metal microwires of the metal microwire array are made of one or more of platinum wires, platinum-iridium alloy wires, or gold wires; and the metal microwires are used to detect surrounding electrophysiological signals.

[0011] Optionally, the end of the metal microfilament is flush with the end face of the optical fiber matrix; or, The ends of the metal microfilaments protrude from the end surface of the optical fiber matrix.

[0012] Optionally, the encapsulation layer is made of photosensitive polymer.

[0013] To solve the above problems, the present application provides a method for preparing a composite optical fiber probe, comprising: A femtosecond laser micromachining method is used to perform a groove process on the outer cladding of a pre-selected optical fiber substrate, thereby forming a microchannel array of predetermined design dimensions on the outer cladding of the optical fiber substrate, wherein the microchannel array includes at least one groove; Using a micromanipulator to place at least one metal microwire in each of the grooves of the prepared microchannel array; The grooves in which the metal microwires are arranged are packaged and solidified to complete the preparation of the composite optical fiber probe.

[0014] Optionally, the method of using a femtosecond laser micromachining method to groove the outer cladding of a pre-selected optical fiber substrate to form a microchannel array of a predetermined design size on the outer cladding of the optical fiber substrate specifically includes: Using a femtosecond laser with predetermined focusing parameters, focusing the laser beam on the outer surface of the outer cladding of the optical fiber substrate using a focusing objective lens, wherein the focusing parameters include wavelength, pulse width, repetition rate and energy; The optical fiber substrate is subjected to scanning ablation processing by controlling a displacement platform using pre-optimized micromachining parameters to obtain the microchannel array of a predetermined design size.

[0015] Optionally, the encapsulating and curing the grooves in which the metal microwires are arranged specifically includes: Using liquid photosensitive polymer to coat the grooves where the metal microwires are arranged, so that the liquid photosensitive polymer fills the grooves and covers the metal microwires; A light source with a predetermined wavelength is used to irradiate the coating position, so that the liquid photosensitive polymer is cured to form an encapsulation layer.

[0016] Optionally, after encapsulating and curing the grooves in which the metal microwires are arranged, the preparation method further comprises: Cutting and polishing the first end of the composite optical fiber probe to determine the relative position of the metal microfilament end and the end face of the optical fiber matrix; Each of the metal microwires at the second end of the composite optical fiber probe is electrically connected to a signal receiving end to extract an electrophysiological signal.

[0017] The beneficial effects of this application are as follows: This method does not rely on integrated thermal stretching, but is processed and integrated on the outer cladding of a finished, fully structured quartz-based optical fiber (especially hollow-core optical fiber), thereby completely solving the thermal incompatibility problem between quartz-based materials and metal materials. Utilizing femtosecond laser cold ablation technology, a microchannel array for accommodating metal microwires is precisely and controllably etched on the surface of the optical fiber cladding. This processing process has concentrated energy and a very small heat-affected zone, ensuring that the optical transmission structure of the optical fiber's internal core (such as the fiber core, capillary wall, etc.) is not damaged, thereby maintaining the original excellent optical performance of the optical fiber. By embedding metal microwires into microchannels and encapsulating and fixing them with photosensitive polymers, the electrode array and the optical fiber are physically integrated, with a compact structure and controllable size, and the electrode layout can be flexibly defined by the laser processing program.

[0018] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are specifically listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present invention. The same reference symbols are used throughout the drawings to represent the same components. In the drawings: Figure 1 A schematic structural diagram of a composite optical fiber probe with an integrated electrode array provided in an embodiment of the present application is shown; Figure 2 is a schematic cross-sectional view of an antiresonant hollow-core optical fiber used as an optical fiber matrix in one embodiment of the present application; Figure 3 Schematic diagram of the transmission loss curve of the antiresonant hollow-core optical fiber in the visible to near-infrared band according to an embodiment of the present application; Figure 4 A schematic diagram of a process for preparing a composite optical fiber probe provided in an embodiment of the present application is shown; Figure 5 Schematic diagram of the working principle of the composite optical fiber probe of the present invention in optogenetic applications; Figure 6 A schematic flow chart of another method for preparing a composite optical fiber probe provided in an embodiment of the present application is shown.

[0020] The reference numerals indicate: 100 - optical fiber substrate; 101 - fiber core; 102 - microstructured cladding; 103 - outer cladding; 104 - microchannel array; 105 - metal microwire array; 106 - packaging layer; 200 - neurons. DETAILED DESCRIPTION

[0021] Various aspects and features of the present application are described herein with reference to the accompanying drawings.

[0022] It should be understood that various modifications may be made to the embodiments of the present application. Therefore, the above description should not be considered as limiting, but merely as an example of an embodiment. Other modifications within the scope and spirit of the present application will occur to those skilled in the art.

[0023] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present application and, together with the general description of the present application given above and the detailed description of the embodiments given below, serve to explain the principles of the present application.

[0024] These and other characteristics of the present application will become apparent from the following description of a preferred form of embodiment given as a non-limiting example with reference to the accompanying drawings.

[0025] It should also be understood that although the present application has been described with reference to certain specific examples, those skilled in the art will readily be able to implement many other equivalent forms of the present application.

[0026] The above and other aspects, features and advantages of the present application will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

[0027] Specific embodiments of the present application will be described hereinafter with reference to the accompanying drawings; however, it should be understood that the embodiments described are merely examples of the present application and may be implemented in a variety of ways. Familiar and / or repetitive functions and structures are not described in detail to avoid obscuring the present application with unnecessary or redundant details. Therefore, the specific structural and functional details described herein are not intended to be limiting, but rather serve merely as a basis and representative basis for the claims to teach those skilled in the art to variously utilize the present application with substantially any suitable detailed structure.

[0028] This specification may use the phrases "in one embodiment," "in another embodiment," "in yet another embodiment," or "in other embodiments," which may all refer to one or more of the same or different embodiments according to the present application.

[0029] Reference Figure 1 and Figure 2 , the embodiment of the present application provides a composite optical fiber probe with an integrated electrode array, comprising: an optical fiber substrate 100, a microchannel array 104, a metal microwire array 105 and an encapsulation layer 106; The microchannel array includes at least one groove, and each groove is provided on the outer cladding 103 of the optical fiber substrate 100; The metal microwire array 105 includes at least one metal microwire, and each of the metal microwires is embedded in the groove of the microchannel array 104; The packaging layer 106 fills the groove, embeds and fixes the metal microwires inside the groove, and forms a continuous integral surface with the outer surface of the outer cladding layer 103 .

[0030] In this embodiment, the optical fiber matrix 100 is a hollow-core microstructured optical fiber, comprising a hollow core 101, a microstructured cladding 102 surrounding the core, and an outer cladding 103 located outside the microstructured cladding. The optical fiber matrix 100 may be an antiresonant hollow-core fiber, a photonic bandgap fiber, or a total internal reflection photonic crystal fiber. The optical fiber matrix 100 of the present application exhibits a diversity of light transmission modes. The unique light-guiding mechanism of the hollow-core fiber not only efficiently transmits continuous light used in conventional optogenetic experiments, but also losslessly transmits ultrashort pulsed lasers with high peak power (such as femtosecond lasers). This characteristic is crucial for realizing cutting-edge neuroscience applications. For example, femtosecond lasers can be used for two-photon optogenetics to achieve precise three-dimensional spatial excitation of single neurons 200. Alternatively, femtosecond lasers can be used to transmit two-photon imaging while performing optogenetic manipulation, achieving co-location integration of stimulation and imaging. The fiber matrix 100 of this application achieves high-contrast cylindrical volume illumination. The antiresonant hollow-core fiber has an extremely low numerical aperture (NA), resulting in an extremely low divergence angle for the light beam emitted from the fiber end face. This characteristic significantly suppresses lateral scattering of light in brain tissue, resulting in a "cylindrical" illumination volume with sharp horizontal boundaries and abrupt contours, rather than the fuzzy, diffuse light field produced by traditional high-NA optical fibers. This high-contrast cylindrical illumination enables the probe to precisely target the functional columns of neurons 200, precisely activating neuronal populations within the target functional column while minimizing non-target activation of adjacent functional columns. This is crucial for understanding the functional organization and computational principles of cortical microcircuits. The fiber matrix is ​​used to transmit optical signals along the axis of its core.

[0031] The depth of the grooves of the microchannel array 104 is less than the thickness of the outer cladding; the grooves do not penetrate the microstructure cladding of the optical fiber matrix and the core of the optical fiber matrix.

[0032] In this embodiment, the microchannel array 104 is one or more groove structures formed on the outer cladding 103 of the optical fiber substrate 100 by femtosecond laser ablation. The depth of each groove is less than the thickness of the outer solid cladding 103, ensuring that it does not penetrate the microstructured cladding 102 or the fiber core 101, thereby not affecting the optical performance of the optical fiber.

[0033] The metal microwire array 105 is composed of one or more conductive metal microwires, each of which is embedded in a groove of the microchannel array 104. In one specific embodiment, the metal microwire array 105 may include two platinum wires with a diameter of 10 μm, symmetrically arranged on either side of the optical fiber substrate. In other embodiments, a larger number of electrodes can be prepared as needed. The metal microwires are preferably made of platinum (Pt) wire, platinum-iridium (Pt-Ir) alloy wire, or gold (Au) wire, all of which have good biocompatibility and conductivity. The metal microwire array is used to detect electrophysiological signals around the probe.

[0034] The end of the metal filament is flush with the end surface of the optical fiber matrix; or the end of the metal filament protrudes from the end surface of the optical fiber matrix.

[0035] In a preferred embodiment, Figure 1 As shown, the end of the metal microwire array 105 protrudes from the end face of the optical fiber substrate 100 by a predetermined length, for example, 10 to 50 microns. This configuration allows the electrode tip to be closer to the neuronal signal source and penetrate the glial scar layer that may form at the interface after long-term implantation, thereby significantly improving the signal-to-noise ratio of the recorded signal, making it particularly suitable for long-term chronic in vivo experiments.

[0036] In another preferred embodiment, the end of the metal microwire array 105 is substantially flush with the end face of the optical fiber matrix 100. This configuration has a smooth end face profile, which can minimize tissue damage during implantation and has the highest mechanical strength, making it suitable for acute experiments or applications that are extremely sensitive to tissue disturbances.

[0037] The encapsulation layer 106 can be a biocompatible photosensitive polymer, such as a UV-curable adhesive. It fills the groove structure, embeds and fixes the metal microwire array 105, and its outer surface after curing forms a smooth and continuous whole with the outer surface of the outer solid coating 103 to reduce tissue damage during implantation.

[0038] This application adopts a "post-processing composite" strategy to perform processing on the finished quartz-based optical fiber, avoiding the incompatibility problem between quartz and metal in the hot stretching process. By using femtosecond laser direct writing technology, one, two or even more electrodes can be precisely integrated on the optical fiber according to experimental requirements. Their position, spacing and arrangement can be flexibly customized, realizing flexible layout and customizable integration of electrodes. By controlling the end position of the metal microwire, a probe can be prepared in which the electrode is flush with the end face of the optical fiber or the electrode protrudes from the end face of the optical fiber. The former has the lowest trauma, and the latter has a higher signal-to-noise ratio and is conducive to long-term recording, which can meet the specific needs of different application scenarios and realize configurable optimization of the optical-electrical interface. By using femtosecond laser cold ablation technology, the processing process does not damage the internal core structure of the optical fiber, so that the probe can fully retain the excellent optical properties of high-performance hollow-core optical fiber. The electrode is directly embedded in the optical fiber cladding, avoiding the extra volume caused by mechanical bundling, and the structure is compact, which can effectively reduce implantation trauma and realize compact integration and miniaturization. The antiresonant hollow-core optical fiber used in the present invention can losslessly transmit ultrashort pulses such as femtosecond lasers with high peak power, and realize high-contrast columnar volume illumination, which is used for precise targeting of neuronal functional columns, with diverse optical signal transmission modes and precise illumination control.

[0039] In a specific and preferred embodiment, the antiresonant hollow core fiber as the optical fiber matrix 100 is characterized. The cross-sectional micrograph and transmission loss curve thereof can be referred to the attached drawings. Figure 2 and attached Figure 3 The specific dimensional parameters of the optical fiber are as follows: the diameter of the core 101 is 25-27 µm; the microstructured cladding 102 is composed of multiple hollow capillaries that do not touch each other, and the diameter of each capillary is 13-16 µm; the diameter of the outer cladding 103 is 160 µm. The results of optical performance tests show that the transmission loss of this optical fiber is less than 0.1 dB / m in the wide spectral range of 520 nm to 1000 nm (covering most commonly used activation wavelengths in optogenetics). This excellent optical performance not only ensures that conventional continuous light can be transmitted with extremely high efficiency, providing a reliable foundation for standard optogenetic experiments; more importantly, its hollow core structure and low dispersion characteristics also enable it to losslessly transmit high-peak power femtosecond pulse lasers, providing the necessary optical pathway for realizing cutting-edge neuroscience applications such as two-photon optogenetics and in vivo imaging.

[0040] Another embodiment of the present application provides a method for preparing a composite optical fiber probe, such as Figure 4 Shown, including: Step S301: groove the outer cladding of a pre-selected optical fiber substrate using a femtosecond laser micromachining method to form a microchannel array of predetermined design dimensions on the outer cladding of the optical fiber substrate, wherein the microchannel array includes at least one groove; During this step, the optical fiber substrate 100 is fixed to a precision three-dimensional displacement platform. A femtosecond laser (e.g., with a wavelength of 1030 nm and a pulse width of <500 fs) is used to focus the laser beam onto the surface of the optical fiber's outer solid cladding 103 via a focusing objective lens. According to a preset array pattern, the displacement platform or galvanometer is controlled to perform scanning ablation, forming a microchannel array 104. Ablation parameters (e.g., laser power, repetition rate, and scanning speed) are precisely optimized to ensure clean channel edges and no thermal damage.

[0041] Step S302: using a micromanipulator to place at least one metal microwire in each of the grooves of the prepared microchannel array; During the specific implementation of this step, a micromanipulator or other precision equipment is used to accurately place multiple metal microwires into each of the prepared microchannels, ie, grooves, and at least one metal microwire constitutes the metal microwire array 105 .

[0042] Step S303: encapsulating and curing the grooves in which the metal microwires are arranged, thereby completing the preparation of the composite optical fiber probe.

[0043] During this step, a layer of liquid UV-curable adhesive is applied to the optical fiber surface, completely filling the microchannels and covering the metal microwires. Subsequently, a UV light source with a specific wavelength (e.g., 365 nm) is used to irradiate the optical fiber, causing the UV-curable adhesive to polymerize and cure, forming a strong, transparent encapsulation layer 106.

[0044] Reference Figure 5 In optogenetic applications, the probe of the present invention transmits an input light signal to brain tissue via the fiber core 101, thereby stimulating neurons 200. Simultaneously, the metal microwire array 105 records the electrophysiological signals generated by the activity of neurons 200, thereby achieving simultaneous light stimulation and electrical recording.

[0045] The composite fiber probe fabricated in this application utilizes femtosecond laser cold ablation technology, a process that leaves the fiber's core structure intact, allowing the probe to fully retain the superior optical properties of high-performance hollow-core fiber. Directly embedding the electrodes into the fiber cladding avoids the additional bulk associated with mechanical bundling, resulting in a compact structure and minimizing implant trauma.

[0046] Another embodiment of the present application provides a method for preparing a composite optical fiber probe, such as Figure 6 Shown, including: Step S401: cleaning the pre-selected optical fiber substrate; During the specific implementation of this step, a pre-selected finished quartz-based hollow-core optical fiber is cleaned. The finished quartz-based hollow-core optical fiber can be an anti-resonant hollow-core optical fiber (ARHCF), a photonic bandgap optical fiber (PBG-HCF), or a total internal reflection photonic crystal optical fiber. Acetone, ethanol, and deionized water can be used for ultrasonic cleaning in sequence, and then nitrogen is used for drying to avoid fiber contamination. The optical fiber matrix (100) can also be other types of hollow-core optical fibers or traditional solid-core optical fibers.

[0047] Step S402: using a femtosecond laser with predetermined focusing parameters, and focusing the laser beam on the outer surface of the outer cladding of the optical fiber substrate using a focusing objective lens; During the specific implementation of this step, the focusing parameters include wavelength, pulse width, repetition rate, and energy. The wavelength can be in the near-infrared band of 1030 nm to reduce thermal effects; the pulse width can be 300-500 fs to balance processing accuracy and efficiency; the repetition rate can be a high repetition rate of 100 kHz-1 MHz to improve efficiency; and the energy can be 0.1-10 μJ and must be calibrated to above the ablation threshold. The focusing parameters are selected and adjusted based on the actual size of the composite fiber probe.

[0048] Step S403: using pre-optimized micromachining parameters to control the displacement platform to perform scanning ablation processing on the optical fiber substrate to obtain the microchannel array of a predetermined design size; During the specific implementation of this step, the optical fiber is fixed on a six-axis displacement platform with an accuracy of 0.1 μm. The micromachining parameters include: laser power, repetition frequency and scanning speed. The displacement platform is controlled using the pre-optimized micromachining parameters to perform scanning ablation on the optical fiber substrate to obtain the microchannel array of the predetermined design size. The ablation parameters are precisely optimized to ensure that the channel edges are neat and free of thermal damage.

[0049] Step S404: using a micromanipulator to place at least one metal microwire into each groove of the prepared microchannel array; During this step, precision equipment such as a micromanipulator is used to precisely place multiple metal microwires into the prepared microchannel grooves. Using a micromanipulator (e.g., a Sutter MP-285) under a microscope, the microwires are slowly inserted into the microchannels, with their ends protruding 50-100 μm beyond the fiber end face. The metal microwires of the metal microwire array can be made of one or more of platinum, platinum-iridium alloy, or gold. Metal microwire array 105 can also be made of tungsten, stainless steel, or a surface-modified conductive material.

[0050] Step S405: coating the grooves where the metal microwires are arranged with liquid photosensitive polymer, so that the liquid photosensitive polymer fills the grooves and covers the metal microwires; During the specific implementation of this step, a layer of liquid UV-curing glue is coated on the surface of the optical fiber to completely fill the microchannel and cover the metal microwires.

[0051] Step S406: irradiating the coating position with a light source of a predetermined wavelength to solidify the liquid photosensitive polymer to form an encapsulation layer; During the specific implementation of this step, a UV light source of a specific wavelength (eg, 365 nm) is used to irradiate the optical fiber, causing the UV curing adhesive to polymerize and cure, thereby forming a strong, transparent, and biocompatible transparent encapsulation layer.

[0052] Step S407: cutting and polishing the first end of the composite optical fiber probe to determine the relative position of the metal microfilament end and the end face of the optical fiber matrix; During this step, the working end of the probe is cut and polished to ensure a flat cross-section between the fiber end face and the electrode. Precise micro-nano manipulation and selective polishing can be used to achieve a flush or protruding configuration between the metal microwire end face and the fiber end face, as needed.

[0053] Step S408: electrically connecting each of the metal microwires at the second end of the composite optical fiber probe to a signal receiving end to extract an electrophysiological signal.

[0054] During this step, at the other end of the probe, the ends of the metal microwires are connected to a circuit board or connector via conductive adhesive, micro-soldering, or other methods to extract electrophysiological signals. Specifically, each metal microwire can be electrically connected to a signal receiving end (e.g., a PCB or connector) via conductive adhesive or micro-soldering to extract electrophysiological signals.

[0055] This application adopts a "post-processing composite" strategy to perform processing on the finished quartz-based optical fiber, avoiding the incompatibility problem between quartz and metal in the hot stretching process. By using femtosecond laser direct writing technology, one, two or even more electrodes can be precisely integrated on the optical fiber according to experimental requirements. Their position, spacing and arrangement can be flexibly customized, realizing flexible layout and customizable integration of electrodes. By controlling the end position of the metal microwire, a probe can be prepared in which the electrode is flush with the end face of the optical fiber or the electrode protrudes from the end face of the optical fiber. The former has the lowest trauma, and the latter has a higher signal-to-noise ratio and is conducive to long-term recording, which can meet the specific needs of different application scenarios and realize configurable optimization of the optical-electrical interface. By using femtosecond laser cold ablation technology, the processing process does not damage the internal core structure of the optical fiber, so that the probe can fully retain the excellent optical properties of high-performance hollow-core optical fiber. The electrode is directly embedded in the optical fiber cladding, avoiding the extra volume caused by mechanical bundling, and the structure is compact, which can effectively reduce implantation trauma and realize compact integration and miniaturization. The antiresonant hollow-core optical fiber used in the present invention can losslessly transmit ultrashort pulses such as femtosecond lasers with high peak power, and realize high-contrast columnar volume illumination, which is used for precise targeting of neuronal functional columns, with diverse optical signal transmission modes and precise illumination control.

[0056] The above embodiments are merely exemplary embodiments of the present application and are not intended to limit the scope of the present application. The scope of protection of the present application is defined by the claims. Those skilled in the art may make various modifications or equivalent substitutions to the present application within the essence and scope of protection of the present application, and such modifications or equivalent substitutions shall also be deemed to fall within the scope of protection of the present application.

Claims

1. A composite optical fiber probe with an integrated electrode array, characterized in that: include: Optical fiber substrate, microchannel array, metal microwire array and packaging layer; The microchannel array comprises at least one groove, each of which is arranged on the outer cladding of the optical fiber substrate; The metal microwire array includes at least one metal microwire, and each of the metal microwires is embedded in the groove of the microchannel array; The packaging layer fills the groove, embeds and fixes the metal microwires in the groove, and forms a continuous integral surface with the outer surface of the outer cladding layer.

2. The composite optical fiber probe according to claim 1, wherein: The optical fiber matrix is ​​a hollow core microstructure optical fiber, comprising a hollow core, a microstructure cladding arranged around the core, and the outer cladding located outside the microstructure cladding; The microstructure cladding comprises a plurality of hollow capillary pores for guiding light, which are arranged around the fiber core and do not contact each other, and the plurality of hollow capillary pores form an anti-resonance light guiding structure; The optical fiber matrix is ​​used to transmit optical signals along the axis of the fiber core.

3. The composite optical fiber probe according to claim 2, wherein: The depth of the grooves of the microchannel array is less than the thickness of the outer cladding; The groove does not penetrate the microstructure cladding of the optical fiber matrix and the core of the optical fiber matrix.

4. The composite optical fiber probe according to claim 1, wherein: The metal microwires of the metal microwire array are made of one or more of platinum wires, platinum-iridium alloy wires, or gold wires; the metal microwires are used to detect surrounding electrophysiological signals.

5. The composite optical fiber probe according to claim 1, wherein: The end of the metal microfilament is flush with the end face of the optical fiber matrix; or, The ends of the metal microfilaments protrude from the end surface of the optical fiber matrix.

6. The composite optical fiber probe according to claim 1, wherein: The material of the encapsulation layer is photosensitive polymer.

7. A method for preparing a composite optical fiber probe, characterized in that: include: A femtosecond laser micromachining method is used to perform a groove process on the outer cladding of a pre-selected optical fiber substrate, thereby forming a microchannel array of predetermined design dimensions on the outer cladding of the optical fiber substrate, wherein the microchannel array includes at least one groove; Using a micromanipulator to place at least one metal microwire in each of the grooves of the prepared microchannel array; The grooves in which the metal microwires are arranged are packaged and solidified to complete the preparation of the composite optical fiber probe.

8. The preparation method according to claim 7, wherein The method of using a femtosecond laser micromachining method to groove the outer cladding of a pre-selected optical fiber substrate to form a microchannel array of a predetermined design size on the outer cladding of the optical fiber substrate specifically includes: Using a femtosecond laser with predetermined focusing parameters, focusing the laser beam on the outer surface of the outer cladding of the optical fiber substrate using a focusing objective lens, wherein the focusing parameters include wavelength, pulse width, repetition rate and energy; The optical fiber substrate is subjected to scanning ablation processing by controlling a displacement platform using pre-optimized micromachining parameters to obtain the microchannel array of a predetermined design size.

9. The preparation method according to claim 7, wherein The step of encapsulating and curing the grooves in which the metal microwires are arranged specifically includes: Using liquid photosensitive polymer to coat the grooves where the metal microwires are arranged, so that the liquid photosensitive polymer fills the grooves and covers the metal microwires; A light source with a predetermined wavelength is used to irradiate the coating position, so that the liquid photosensitive polymer is cured to form an encapsulation layer.

10. The preparation method according to claim 7, wherein After encapsulating and curing the grooves in which the metal microwires are arranged, the preparation method further comprises: Cutting and polishing the first end of the composite optical fiber probe to determine the relative position of the metal microfilament end and the end face of the optical fiber matrix; Each of the metal microwires at the second end of the composite optical fiber probe is electrically connected to a signal receiving end to extract an electrophysiological signal.

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