CN219657464U - Optical fiber coupling reflection-based photoacoustic microscopic imaging system - Google Patents

Abstract

The utility model relates to the technical field of biomedical detection, and particularly discloses a photoacoustic microscopic imaging system based on optical fiber coupling reflection; the device comprises a light source unit, an optical fiber coupling unit, a reflection excitation-ultrasonic sensing integrated unit, a sample testing unit and a signal processing control unit; the optical fiber coupling unit sequentially comprises an incident light optical fiber coupler, an optical fiber and an emergent light optical fiber coupler along the light transmission direction; the reflection type excitation-ultrasonic sensing integrated unit is positioned at the rear end of the optical fiber coupling unit, and the sample testing unit is positioned right below the reflection type excitation-ultrasonic sensing integrated unit; the signal processing control unit sequentially comprises a signal amplifier, a signal filter, a data acquisition card, a computer, a three-dimensional scanning platform controller and a three-dimensional scanning platform along the signal transmission direction; the photoacoustic microscopic imaging system has a simple structure, is easier to debug an optical path, can realize photoacoustic microscopic imaging of tissues to be measured in different shapes, and has wider applicability.

Description

Optical fiber coupling reflection-based photoacoustic microscopic imaging system

Technical Field

The utility model relates to the technical field of biomedical detection, in particular to a photoacoustic microscopic imaging system based on optical fiber coupling reflection.

Background

In biomedical diagnosis and treatment, image analysis is often required to be performed on internal tissues, organs and the like of a living body, so that targeted accurate treatment is performed. In the prior art, the photoacoustic microscopy imaging has the advantages of pure optical high resolution and pure ultrasonic high contrast due to the adoption of a photoinduced ultrasonic technology. The pulse laser is utilized to be incident to the tested tissue, and the tested tissue absorbs the incident laser to generate local temperature rapid rise and fall, so that the local tissue generates rapid expansion and contraction, and further ultrasonic mechanical waves are generated, namely: photoacoustic signals. The photoacoustic imaging technology is a nondestructive, rapid and convenient biomedical photonics imaging technology, and is combined with a microscopic imaging technology on the basis of the photoacoustic imaging technology, so that the imaging of micro-areas (submicron to millimeter areas) of biological tissues can be realized, the submicron high-resolution can be realized, and meanwhile, the imaging of tissues with the depth of about 10mm below the skin can be realized.

However, in the prior art photoacoustic microscopy imaging technique, two types of photoacoustic microscopy imaging are mainly separated by optical resolution and photoacoustic microscopy imaging are mainly separated by acoustic resolution. In the optical resolution photoacoustic microscopic imaging, mainly three modes of forward, lateral and backward modes are adopted, wherein the forward mode is applicable to only thin-layer tissue imaging, and the imaging penetration depth of the tissue with larger volume is limited; the lateral type has very limited application range due to the characteristics of the structural mode; the backward optical resolution photoacoustic microscopic imaging technology has certain complexity on the structure of an imaging system, and certain difficulties exist in system debugging and maintenance, so that the photoacoustic microscopic imaging device can only be in laboratory research at present, and is not beneficial to field detection and practical clinical application.

Disclosure of Invention

The present utility model aims to solve at least one of the technical problems existing in the prior art. Therefore, the utility model provides a reflective photoacoustic microscopic imaging system based on optical fiber coupling.

An embodiment of the present utility model provides an optical fiber coupling reflective photoacoustic microscopy imaging system, including: the device comprises a light source unit, an optical fiber coupling unit, a reflection excitation-ultrasonic sensing integrated unit, a sample testing unit and a signal processing control unit; the optical fiber coupling unit is positioned at the rear end of the light source unit; the optical fiber coupling unit sequentially comprises an incident light optical fiber coupler, an optical fiber and an emergent light optical fiber coupler along the light transmission direction; the optical fiber coupling unit transmits the pulse laser emitted by the light source unit; the reflection type excitation-ultrasonic sensing integrated unit is positioned at the rear end of the optical fiber coupling unit, and the sample testing unit and the reflection type excitation-ultrasonic sensing integrated unit are coaxial in the vertical direction; the reflection excitation-ultrasonic sensing integrated unit acquires information and transmits the information to the signal processing control unit; the signal processing control unit sequentially comprises a signal amplifier, a signal filter, a data acquisition card, a computer, a three-dimensional scanning platform controller and a three-dimensional scanning platform along the signal transmission direction.

According to the optical fiber coupling reflection-based photoacoustic microscopic imaging system, the optical fiber coupling unit and the light source unit are matched, so that the defects of difficult optical path debugging and the like caused by more optical devices in an optical path can be reduced, the optical path structure is simpler, and the optical path debugging is easy; the reflective excitation-ultrasonic sensing integrated unit is arranged, so that the reflective objective lens and the miniature ultrasonic detector are positioned on the same side of the tested tissue, the tested tissue with any shape and any part can be subjected to photoacoustic microscopic imaging conveniently, and the clinical practicability is wider; the miniature ultrasonic detector and the reflection type objective lens integrated structure is adopted, so that the volume of the photoacoustic microscopic imaging device is smaller, the excitation detection integrated photoacoustic microscopic imaging probe is easy to manufacture, and the device is practical, flexible and convenient; the whole photoacoustic microscopic imaging system is more convenient to operate and control through the arrangement of the signal processing control unit.

According to some embodiments of the utility model, the light source unit comprises a pulse laser, a diaphragm, a first focusing lens, a filter shaping aperture, and a first collimating lens; the diaphragm is arranged at the front end of the beam outlet of the pulse laser; the first focusing lens focuses the light beam passing through the diaphragm; the first collimating lens expands and collimates the light beam passing through the filtering and shaping hole and transmits the light beam to the incident light fiber coupler; the first focusing lens, the filtering shaping hole and the first collimating lens are positioned on the same horizontal axis; the filtering shaping hole is arranged at a focus of the first focusing lens for focusing the light beam; the incident light optical fiber coupler comprises a second focusing lens, an incident light optical fiber coupling head and an optical fiber adjusting bracket; the second focusing lens converges and transmits the beam-expanding collimated light beam to the incident light fiber coupling head; the incident light optical fiber coupling head is arranged on the optical fiber adjusting bracket; one end of the incident light optical fiber coupling head is connected with an optical fiber. Providing a light beam by the light source unit; the optical fiber adjusting bracket is used for adjusting the position of the optical fiber coupler of the incident light so as to facilitate the adjustment of the optical path, and the incident laser beam is led into the optical fiber to the maximum extent for transmission.

According to some embodiments of the utility model, the outgoing light fiber coupler comprises a fiber fixing bracket, an outgoing light fiber coupling head and a second collimating lens, wherein the fiber fixing bracket fixes the fiber outlet end; and the second collimating lens collimates and transmits the light beam emitted by the emergent light fiber coupling head to the reflection excitation-ultrasonic sensing integrated unit. The reflection type excitation-ultrasonic sensing integrated unit sequentially comprises a reflection type objective lens, a miniature ultrasonic detector and a quartz sealing cover according to the light transmission direction, and the reflection type objective lens light beam emergent window and the miniature ultrasonic detector are sealed in the quartz sealing cover. The reflection type objective lens and the miniature ultrasonic detector are of a coaxial confocal structure, and the reflection type objective lens is overlapped with a focus area of the miniature ultrasonic detector. The reflection type objective lens comprises a convex reflector and a concave reflector, wherein the convex reflector totally reflects the collimated light beams output by the optical fiber coupling unit, the concave reflector is of a concave structure with a round hole in the middle, and the concave reflector totally reflects the light beams reflected by the convex reflector. The beam quality is improved by the reflective objective lens arrangement.

According to some embodiments of the utility model, the computer controls the data acquisition card to acquire, the data to save, the pulse laser to start and the parameters to set, and the three-dimensional scanning controller to start and the scanning parameters to set through a data acquisition control program. The emergent light fiber coupler and the reflective excitation-ultrasonic sensing integrated unit are connected to the three-dimensional scanning platform through a connecting bracket. And under the drive of a three-dimensional scanning platform controller controlled by a computer program, the three-dimensional scanning platform can move on a space position, and three-dimensional translation scanning is performed according to a set moving step length.

Additional aspects and advantages of the utility model will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the utility model.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present utility model, and that other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of a fiber-based coupled reflective photoacoustic microscopy imaging system in accordance with an embodiment of the present utility model;

FIG. 2 is a schematic diagram of an incident light fiber coupler of a fiber coupling unit according to an embodiment of the present utility model;

FIG. 3 is a schematic diagram of an outgoing optical fiber coupler of a fiber coupling unit according to an embodiment of the present utility model;

fig. 4 is a schematic diagram of a reflective excitation-ultrasonic sensing integrated unit according to an embodiment of the utility model.

Reference numerals:

100. a light source unit;

101. a pulsed laser; 102. a diaphragm; 103. a first focusing lens; 104. a filtering shaping hole; 105. a first collimating lens;

200. an optical fiber coupling unit;

210. an incident light fiber coupler; 211. a second focusing lens; 212. an incident light fiber optic coupling head; 213. an optical fiber adjusting bracket;

220. an optical fiber; 230. an outgoing optical fiber coupler; 231. an optical fiber fixing bracket; 232. an outgoing optical fiber coupling head; 233 a second collimating lens;

300. a reflection excitation-ultrasonic sensing integrated unit;

310. a reflective objective lens; 311. a convex mirror; 312. a concave mirror;

320. a miniature ultrasound probe; 330. a quartz seal cover;

400. a sample testing unit;

401. a tissue to be tested; 402. a sample holder; 403. a water tank;

500. signal processing control unit

501. A signal amplifier; 502. a signal filter; 503. a data acquisition card; 504. a computer; 505. a three-dimensional scanning platform controller; 506. a three-dimensional scanning platform.

Detailed Description

The following detailed description of embodiments of the utility model, with reference to the accompanying drawings, is illustrative of the embodiments described herein, and it is to be understood that the specific embodiments described herein are merely illustrative of the utility model and are not limiting of the utility model.

It will be understood that when an element is referred to as being "fixed to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs. The terminology used herein in the description of the utility model is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

Example 1

Referring to fig. 1, the present embodiment provides a fiber coupling reflection type photoacoustic microscopic imaging system, which includes:

the device comprises a light source unit 100, an optical fiber coupling unit 200, a reflection excitation-ultrasonic sensing integrated unit 300, a sample testing unit 400 and a signal processing control unit 500; wherein the optical fiber coupling unit 200 is located at the rear end of the light source unit 100; the optical fiber coupling unit 200 sequentially includes an incident optical fiber coupler 210, an optical fiber 220, and an emergent optical fiber coupler 230 according to the optical transmission direction; the optical fiber coupling unit 200 transmits the pulse laser emitted from the light source unit 100; the reflection type excitation-ultrasonic sensing integrated unit 300 is positioned at the rear end of the optical fiber coupling unit 200, and the sample testing unit 400 is coaxial with the reflection type excitation-ultrasonic sensing integrated unit 300 in the vertical direction; the information collected by the reflection excitation-ultrasonic sensing integrated unit 300 is transmitted to the signal processing control unit 500; the signal processing control unit 500 sequentially includes a signal amplifier 501, a signal filter 502, a data acquisition card 503, a computer 504, a three-dimensional scanning platform controller 505 and a three-dimensional scanning platform 506 along the signal transmission direction. The optical fiber coupling unit 200 is matched with the light source unit 100, so that the defects of difficult optical path debugging and the like caused by more optical devices in an optical path can be reduced, the optical path structure is simpler, and the optical path debugging is easy. The reflection type excitation-ultrasonic sensing integrated unit 300 is arranged, so that the reflection type objective 310 and the micro ultrasonic detector 320 are positioned on the same side of the tested tissue, and the tested tissue with any shape and any part can be subjected to photoacoustic microscopic imaging conveniently, so that the clinical practicability is wider; the integrated structure of the miniature ultrasonic detector 310 and the reflective objective 320 is adopted, so that the photoacoustic microscopic imaging device is smaller in size and easy to manufacture into an excitation detection integrated photoacoustic microscopic imaging probe, and the device is more flexible and convenient to use; the arrangement by the signal processing control unit 500 makes the whole photoacoustic microscopy imaging system more advantageous for manipulation.

Further, the light source unit comprises a pulse laser 101, a diaphragm 102, a first focusing lens 103, a filter shaping hole 104 and a first collimating lens 105; the diaphragm 102 is arranged at the front end of the beam outlet of the pulse laser 101; the first focusing lens 103 focuses the light beam passing through the diaphragm 102; the first collimating lens 105 expands and collimates the light beam passing through the filter shaping aperture 104 and transmits the light beam to the incident light fiber coupler 210. The first focusing lens 103, the filter shaping hole 104 and the first collimating lens 105 are positioned on the same horizontal axis; and the filter shaping hole 104 is arranged at the focus of the first focusing lens 103.

Specifically, the pulse laser 101 in the light source unit 100 is an optical parameter oscillation solid pulse laser, the optical parameter oscillation pulse laser is an OPO wavelength tunable pulse laser (OPOletteTM, 532 II, OPOTEK inc., USA) excited by YAG to pump at 532nm, the wavelength tunable range is 680nm-2500nm, the maximum energy of the laser in the effective wavelength range is about 10mJ, the energy is adjustable in the range of 0% -100%, the laser repetition frequency is 20Hz, and the duration is 7ns.

The diaphragm 102 is arranged at the front end of the beam outlet of the pulse laser 101 and is used for filtering out sidelobe scattered light existing in the beam emitted by the pulse laser 101; the first focusing lens 103 is used for focusing the light beam passing through the diaphragm 102 through the first focusing lens 103; the filtering shaping hole 104 is positioned at the focus of the first focusing lens 103, and is used for spatially filtering and shaping the focused Gaussian light spot to improve the quality of the light beam; the first collimating lens 105 expands and collimates the light beam shaped by the filter shaping aperture 104.

Further, the computer 504 controls the data acquisition card 503 to acquire, store data, turn on and parameter setting of the pulse laser 101, and turn on and parameter setting of the three-dimensional scan controller 505 through a data acquisition control program; the outgoing optical fiber coupler 230 and the reflective excitation-ultrasonic sensing integrated unit 300 are connected to the three-dimensional scanning platform 506 through a connection bracket.

Specifically, the signal amplifier 501 in the signal processing and controlling unit 500 is one or more stages of signal amplifiers, which is used for amplifying the photoacoustic signal captured by the micro ultrasonic detector 329; the signal filter 502 is a low-pass or band-pass filter, and functions to filter out high-frequency noise signals; the signal acquisition card 503 acquires the filtered photoacoustic signal and converts the photoacoustic signal into a digital signal, and the signal acquisition card 503 can transmit data in a PCI bus, PXI bus and GPIB serial port communication mode; the computer 504 controls the data acquisition card 503 to acquire and save data through a data acquisition control program, and the pulse laser 201 is turned on and parameters are set, and the three-dimensional scanning controller 505 is turned on and scanning parameters are set; the three-dimensional scanning platform 506 is an electric full-automatic three-dimensional scanning platform, the emergent optical coupler 203 and the reflective excitation-ultrasonic sensing integrated unit 300 are connected and fixed through a connecting bracket, and the three-dimensional scanning platform 506 performs three-dimensional translational scanning leftwards, rightwards, forwards, backwards, upwards and downwards under the drive of the three-dimensional scanning platform controller 505 controlled by the computer 504 program according to a set moving step length.

Example 2

Referring to fig. 2 and 3, the present embodiment specifically describes the incident light fiber coupler 210 and the emergent light fiber coupler 230 in the optical fiber coupling unit 200 based on embodiment 1; wherein, the liquid crystal display device comprises a liquid crystal display device,

the incident light fiber coupler 210 comprises a second focusing lens 211, an incident light fiber coupling head 212 and a fiber adjusting bracket 213; the second focusing lens 211 converges and transmits the expanded collimated light beam to the incident light fiber coupling head 212; the incident light fiber coupling head 212 is mounted on the fiber adjusting bracket 213; one end of the incident light fiber coupling head 212 is connected to an optical fiber 220.

The outgoing optical fiber coupler 230 includes an optical fiber fixing bracket 231, an outgoing optical fiber coupling head 232, and a second collimating lens 233, where the optical fiber fixing bracket 231 fixes the outlet end of the optical fiber 220; the second collimating lens 233 collimates the light beam emitted from the optical fiber coupler 232 and transmits the collimated light beam to the reflective excitation-ultrasonic sensing integrated unit 300. The reflection excitation-ultrasonic sensing integrated unit and the optical fiber coupling unit 200 are in a full connection mode, and the second collimating lens 233 and the reflection objective lens are integrally connected into an integrated structure through a connecting piece.

The second focusing lens 211 converges the light beam of the light source unit 100 after being expanded and collimated by the collimating lens 105, and then enters the incident light fiber coupling head 212, and the incident light fiber coupling head 212 guides the light beam into the optical fiber 220 for transmission; the incident light optical fiber coupling head 212 plays a role of connecting the incident end face of the optical fiber 220, the incident light optical fiber coupling head 212 is fixed on the optical platform by the optical fiber adjusting bracket 213, and the position of the incident end face of the optical fiber 220 can be adjusted by adjusting the left shift, the right shift, the up shift, the down shift, the elevation angle and the depression angle, so that the incident laser beam is guided into the optical fiber 220 to the maximum extent for transmission;

specifically, the optical fiber 220 may be a single-mode optical fiber or a multimode optical fiber as a light beam transmission medium, and the core diameter ranges from 10 μm to 400 μm.

Example 3

Referring to fig. 4, the present embodiment is specifically described with reference to the reflective excitation-ultrasonic sensing integrated unit 300 according to embodiment 1; wherein, the liquid crystal display device comprises a liquid crystal display device,

the reflection excitation-ultrasonic sensing integrated unit 300 sequentially comprises a reflection objective 310, a micro ultrasonic detector 320 and a quartz sealing cover 330 according to the light transmission direction, wherein a light beam emergent window of the reflection objective 310 and the micro ultrasonic detector 320 are sealed in the quartz sealing cover 330;

the reflecting objective 310 and the micro ultrasonic detector 320 are in a coaxial confocal structure, and the reflecting objective 310 coincides with a focal area of the micro ultrasonic detector 320; the reflective objective 310 includes a convex mirror 311 and a concave mirror 312, the convex mirror 311 totally reflects the collimated light beam output from the optical fiber coupling unit 200, the concave mirror 312 has a concave structure with a circular hole in the middle, and the concave mirror 312 totally reflects the light beam reflected by the convex mirror 311.

Specifically, the reflective objective 301 is composed of a convex mirror 311 and a concave mirror 312, as shown in fig. 4; wherein the convex mirror 311 totally reflects the collimated light beam output from the optical fiber coupling unit 300 into the reflection type objective lens 310 by the convex mirror 311; the concave mirror 312 is a concave surface with a circular hole in the middle, and the middle circular hole allows the collimated light beam to be parallel incident on the convex mirror 311, the light reflected by the convex mirror 311 is totally reflected by the concave mirror 312, and then passes through the exit window of the reflective objective 310 to be converged into a focal spot to be incident on the tested tissue 401 of the sample testing unit 400.

Further, the convex mirror 312 is fixed by a bracket at the exit window of the reflective objective 310, and in order to enhance the reflection efficiency of the light beam, the surfaces of the convex mirror 311 and the concave mirror 312 are coated with enhancement films.

Further, the magnification of the reflective objective 310 is 10, 20, 25, 40, 50, 100, and the numerical aperture NA is 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8.

Further, the micro ultrasonic detector 320 is a focusing micro ultrasonic sensor, and the size is not more than 2mm×2mm, and is fixed below the reflective objective lens exit window bracket by waterproof glue; the response center frequency is 10MHz, 20MHz, 50MHz and the like.

Further, the quartz sealing cover 330 seals the exit window of the reflection type objective 310, the exit window holder and the micro ultrasound probe 320 all in the quartz sealing cover, and the interior is filled with deionized water. The reflecting objective 310 and the micro ultrasound probe 320 are in a coaxial confocal structure, and the focus of the reflecting objective 310 coincides with the focus area of the micro ultrasound probe 320.

In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the utility model.

In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the utility model. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples.

It will be apparent that the described embodiments are only some, but not all, embodiments of the utility model. Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application for the embodiment. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly understand that the embodiments described herein may be combined with other embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

While embodiments of the present utility model have been shown and described, it will be understood by those of ordinary skill in the art that: many changes, modifications, substitutions and variations may be made to the embodiments without departing from the spirit and principles of the utility model, the scope of which is defined by the claims and their equivalents.

Claims (9)

1. A fiber-coupled reflective photoacoustic microscopy imaging system, comprising: the device comprises a light source unit (100), an optical fiber coupling unit (200), a reflection excitation-ultrasonic sensing integrated unit (300), a sample testing unit (400) and a signal processing control unit (500); wherein the optical fiber coupling unit (200) is positioned at the rear end of the light source unit (100); the optical fiber coupling unit (200) is sequentially provided with an incident light optical fiber coupler (210), an optical fiber (220) and an emergent light optical fiber coupler (230) along the light transmission direction; the optical fiber coupling unit (200) transmits pulse laser emitted by the light source unit (100); the reflection type excitation-ultrasonic sensing integrated unit (300) is positioned at the rear end of the optical fiber coupling unit (200), and the sample testing unit (400) and the reflection type excitation-ultrasonic sensing integrated unit (300) are coaxial in the vertical direction; the reflection excitation-ultrasonic sensing integrated unit (300) acquires information and transmits the information to the signal processing control unit (500); the signal processing control unit (500) sequentially comprises a signal amplifier (501), a signal filter (502), a data acquisition card (503), a computer (504), a three-dimensional scanning platform controller (505) and a three-dimensional scanning platform (506) along the signal transmission direction.

2. The optical fiber coupling reflection-based photoacoustic microscopy imaging system of claim 1, wherein the light source unit (100) comprises a pulsed laser (101), a diaphragm (102), a first focusing lens (103), a filter shaping aperture (104) and a first collimating lens (105); the diaphragm (102) is arranged at the front end of a beam outlet of the pulse laser (101), and the first focusing lens (103), the filtering shaping hole (104) and the first collimating lens (105) are positioned on the same horizontal axis; the filter shaping hole (104) is arranged at the focus of the first focusing lens (103) for focusing the light beam, and the first focusing lens (103) focuses the light beam passing through the diaphragm (102); the first collimating lens (105) expands and collimates the light beam passing through the filter shaping aperture (104) and transmits the expanded light beam to the incident light fiber coupler (210).

3. The optical fiber coupling reflection-based photoacoustic microscopy imaging system of claim 2, wherein the incident light fiber coupler (210) comprises a second focusing lens (211), an incident light fiber coupler head (212) and a fiber conditioning bracket (213); the second focusing lens (211) converges and transmits the expanded collimated light beam to the incident light fiber coupling head (212); the incident light optical fiber coupling head (212) is arranged on the optical fiber adjusting bracket (213); one end of the incident light optical fiber coupling head (212) is connected with an optical fiber (220).

4. The optical fiber coupling reflection-based photoacoustic microscopy imaging system of claim 1, wherein the outgoing optical fiber coupler (230) comprises a fiber fixing bracket (231), an outgoing optical fiber coupling head (232) and a second collimating lens (233), the fiber fixing bracket (231) being used for fixing the outlet end of the optical fiber (220); the second collimating lens (233) collimates and transmits the light beam emitted by the emergent light fiber coupling head (232) to the reflection type excitation-ultrasonic sensing integrated unit (300).

5. The optical fiber coupling reflection-based photoacoustic microscopy imaging system of claim 4, wherein the reflection excitation-ultrasonic sensing integrated unit (300) comprises a reflection objective (310), a micro-ultrasonic detector (320) and a quartz sealing cover (330) sequentially arranged along the light transmission direction, and the reflection objective (310) light beam exit window and the micro-ultrasonic detector (320) are hermetically arranged in the quartz sealing cover (330).

6. The fiber-coupled reflective photoacoustic microscopy imaging system of claim 5, wherein the reflective objective (310) and the micro-ultrasound probe (320) are in a coaxial confocal configuration, the reflective objective (310) coinciding with a focal region of the micro-ultrasound probe (320).

7. The optical fiber coupling reflection type photoacoustic microscopy imaging system of claim 6, wherein the reflection type objective lens (310) comprises a convex mirror (311) and a concave mirror (312), the convex mirror (311) reflects the collimated light beam output from the optical fiber coupling unit (200), the concave mirror (312) has a concave structure with a circular hole in the middle, and the concave mirror (312) reflects the light beam reflected by the convex mirror (311).

8. The optical fiber coupling reflection type photoacoustic microscopy imaging system of claim 1, wherein the computer (504) controls the data acquisition card (503) acquisition, data storage, the turning on and parameter setting of the pulse laser (101), and the turning on and scanning parameter setting of the three-dimensional scanning controller (505).

9. The optical fiber coupling-based reflective photoacoustic microscopy imaging system of claim 1, wherein the outgoing optical fiber coupler (230) and the reflective excitation-ultrasonic sensing integrated unit (300) are connected to the three-dimensional scanning platform (506) through a connection bracket.