A multi-modal fingerprint collection and detection system and method

Abstract

The present invention discloses a multimodal fingerprint acquisition detection system and method thereof, the system includes: an image acquisition device, an OCT imaging device and a high-resolution pressure acquisition device; the method is that the reference unit reflects light into a fiber coupler, the light entering the sample unit is reflected into the sample unit through the sample and further reflected into the fiber coupler, the fiber coupler superimposes and interferes the reflected light signal and sends it into the image acquisition device, rotates a rotatable double-sided reflector, reflects the light signal through the rotatable double-sided reflector to the camera port and sends it to the camera for imaging; the high-resolution pressure acquisition device collects the light reflected by the sample to the second image acquisition port, and the rotatable double-sided reflector reflects it to the camera port and sends it to the camera for imaging. The present invention can not only obtain high-resolution finger epidermis images and pressure values, but also effectively acquire the finger dermis layer structure, greatly improving the practicality and effectiveness of the fingerprint acquisition detection device.

Description

Technical Field

[0001] The present invention relates to the field of fingerprint acquisition technology, and more particularly to a multi-modal fingerprint acquisition detection system and method thereof. Background Art

[0002] With the development of information technology in today's society, information security and personal safety have become the focus of increasing national attention. Identity authentication, as an important means to ensure information security and personal safety, has been widely used in daily life. However, these applications often encounter problems such as low recognition rate and weak anti-counterfeiting ability when facing large-scale crowd identification. Biometrics are increasingly valued in the field of identity authentication due to their uniqueness and difficulty in forgery. Among them, fingerprints have become the most widely used biometric feature due to their excellent uniqueness, permanence and easy collection.

[0003] However, the fingerprint collection equipment currently on the market has a single collection mode, and most of them use a half-reflective half-mirror to collect fingerprints. The fingerprint pressure, light source conditions, and the resolution of the collection front end have a great impact on the quality of fingerprint imaging during collection, making it difficult to obtain a fingerprint image with high accuracy. In addition, fingerprints on the surface of the finger have the disadvantage of being easy to forge, while fingerprints in the dermis are located 1mm or even deeper under the palm skin, and have the advantages of high accuracy, not easy to forge, and not easy to damage. Optical coherence tomography (OCT) can be used to obtain the dermal papillary lines of human fingers, solving the problem of weak anti-counterfeiting and low recognition rate of traditional fingerprint recognition. However, existing fingerprint collection equipment is difficult to collect the structure of the dermal papillary lines of living people, and can no longer meet the requirements of modern people for identity recognition.

[0004] Therefore, how to provide a multimodal fingerprint acquisition and detection system and method based on OCT technology is a problem that technical personnel in this field urgently need to solve. Summary of the invention

[0005] In view of this, the present invention provides a multimodal fingerprint acquisition and detection system and method thereof, which acquires fingerprint images through an OCT imaging device and a high-resolution pressure acquisition device, thereby not only obtaining high-resolution finger epidermal images and pressure values, but also effectively acquiring the finger dermis structure, thereby greatly improving the practicability of the fingerprint acquisition and detection device.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] A multimodal fingerprint acquisition and detection system, connected to a camera, includes: an image acquisition device, an OCT imaging device, and a high-resolution pressure acquisition device;

[0008] The image acquisition device is provided with a first imaging entrance, a second imaging entrance and a camera entrance, wherein the first imaging entrance and the second imaging entrance are respectively provided on two opposite side surfaces of the image acquisition device, and the camera entrance is provided on a side surface between the side surfaces where the first imaging entrance and the second imaging entrance are provided; a rotatable double-sided reflector is installed in the image acquisition device, wherein the two mirror surfaces of the rotatable double-sided reflector correspond to the first imaging entrance and the second imaging entrance respectively, and the camera entrance is provided corresponding to the camera;

[0009] The OCT imaging device comprises a fiber coupler, a reference unit, a sample unit and an OCT image acquisition box; the reference unit, the sample unit and the OCT image acquisition box are all connected to the fiber coupler, a first image acquisition port on the OCT image acquisition box is arranged corresponding to the first imaging entrance, and a first sample port is arranged on the sample unit;

[0010] The second image acquisition port on the high-resolution pressure acquisition device is arranged correspondingly to the second imaging inlet. The high-resolution pressure acquisition device is also provided with a second sample port, and the first sample port is arranged correspondingly to the second sample port.

[0011] Preferably, a first arc-shaped groove is provided on the top surface of the image acquisition device, a first convex structure is provided on the upper edge of the rotatable double-sided reflector and passes through the first arc-shaped groove, and the rotation of the rotatable double-sided reflector in the image acquisition device is controlled by the first convex structure.

[0012] Preferably, the reference unit, the sample unit and the OCT image acquisition box are all connected to the fiber coupler via optical fibers.

[0013] Preferably, the OCT imaging device further comprises a broadband light source, and the broadband light source is connected to the optical fiber coupler via an optical fiber.

[0014] Preferably, the reference unit includes a first box body, a first light-through hole is arranged on the side of the first box body, and the interior of the first box body includes a first convex lens, a lens, a second convex lens and a first reflecting galvanometer; the first convex lens is arranged correspondingly at the first light-through hole, and the first convex lens, the lens, the second convex lens and the first reflecting galvanometer are arranged in parallel in sequence.

[0015] Preferably, the sample unit includes a second box body, a second light hole is arranged on the side of the second box body, a first sample port is arranged on the opposite side of the second light hole, and the interior of the second box body includes a third convex lens, a second reflecting galvanometer, a scanning galvanometer and a fourth convex lens in sequence; the third convex lens is arranged correspondingly at the second light hole, the second reflecting galvanometer and the third convex lens are arranged inclined correspondingly, the scanning galvanometer and the second reflecting galvanometer are parallel, and the fourth convex lens is arranged correspondingly to the scanning galvanometer; the first sample port is arranged correspondingly to the fourth convex lens.

[0016] Preferably, the OCT image acquisition box is provided with a third light through hole, and a first image acquisition port is provided on the opposite side of the third light through hole, and the OCT image acquisition box includes a fifth convex lens, a grating and a sixth convex lens; the fifth convex lens is correspondingly arranged at the third light through hole, the grating is arranged between the fifth convex lens and the sixth convex lens, and the first image acquisition port is correspondingly arranged to the sixth convex lens.

[0017] A multimodal fingerprint collection and detection method, comprising the following contents:

[0018] The light enters the reference unit and the sample unit respectively through the optical fiber coupler, and the reference unit reflects the light into the optical fiber coupler again. The light entering the sample unit irradiates the sample through the first sample port, and is reflected into the sample unit again and further reflected into the optical fiber coupler. The optical fiber coupler further superimposes and interferes the light signals reflected back from the sample unit and the reference unit, and then sends them into the image acquisition device through the first image acquisition port on the OCT image acquisition box. The rotatable double-sided reflector is rotated to reflect the light signal through the rotatable double-sided reflector to the camera port and sent to the camera for imaging;

[0019] The high-resolution pressure acquisition device collects the light reflected by the sample to the second image acquisition port, and further sends it into the image acquisition device through the second imaging entrance, rotates the rotatable double-sided reflector, and reflects the light signal through the rotatable double-sided reflector to the camera port and sends it to the camera for imaging.

[0020] Preferably, the path of the light in the reference unit is: the light enters the first housing from the first light hole and passes through the first convex lens, the lens and the second convex lens in sequence to the first reflecting galvanometer, is reflected by the first reflecting galvanometer to the second convex lens, and then passes through the lens and the first convex lens in sequence to return to the fiber coupler.

[0021] Preferably, the path of the light in the sample unit is: the light enters the second housing from the second light hole and passes through the third convex lens, the second reflecting galvanometer, the scanning galvanometer and the fourth convex lens in sequence, and irradiates the sample through the first sample port. After being reflected by the sample, the light returns to the sample unit again, and passes through the fourth convex lens, the scanning galvanometer, the second reflecting galvanometer and the third convex lens in sequence, and then enters the fiber coupler through the second light hole.

[0022] It can be seen from the above technical solutions that the present invention discloses a multimodal fingerprint collection and detection system and method thereof, which has the following beneficial effects compared with the prior art:

[0023] (1) The multimodal fingerprint acquisition and detection system includes a high-resolution pressure acquisition device and an OCT imaging device, wherein the high-resolution pressure acquisition device can effectively acquire the morphological features of the finger epidermis at high resolution, and the OCT imaging device uses optical coherence tomography technology to effectively acquire the morphological features of the finger dermis. Therefore, the system can send the primary, secondary and tertiary features of the fingerprint, i.e. the microscopic and macroscopic features of the fingerprint, into the camera for imaging, so that the user can obtain multimodal fingerprint images, which are no longer limited to the fingerprint images of the finger epidermis, breaking through the traditional technical limitations, providing an efficient tool for fingerprint inspection and identification and research, and greatly promoting the research progress of fingerprint technology;

[0024] (2) The system of the present invention is provided with an image acquisition device, and the high-resolution pressure acquisition device and the OCT imaging device share the image acquisition device, which effectively reduces the volume of the system and saves costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0026] Figure 1 The accompanying drawing is a schematic diagram of the overall structure of a multimodal fingerprint collection and detection system provided by the present invention;

[0027] Figure 2 The accompanying drawing is a schematic diagram of the overall structure of an OCT imaging device in a multimodal fingerprint acquisition and detection system provided by the present invention;

[0028] Figure 3 The accompanying drawing is a schematic diagram of the overall structure of a high-resolution pressure acquisition device in a multimodal fingerprint acquisition and detection system provided by the present invention;

[0029] Among them, 1-first imaging entrance, 2-second imaging entrance, 3-camera port, 4-rotatable double-sided reflector, 5-fiber coupler, 6-OCT image acquisition box, 7-first image acquisition port, 8-first sample port, 9-second image acquisition port, 10-second sample port, 11-first arc groove, 12-first convex structure, 13-broadband light source, 14-first box, 15-first light hole, 16-first convex lens, 17-lens, 18-second convex lens, 19-first reflecting galvanometer, 20-second housing, 21-second light-through hole, 22-third convex lens, 23-second reflecting galvanometer, 24-scanning galvanometer, 25-fourth convex lens, 26-third light-through hole, 27-fifth convex lens, 28-grating, 29-sixth convex lens, 30-light channel body, 31-diffuser plate, 32-seventh convex lens, 33-third housing, 34-light source entrance, 35-semi-mirror, 36-second arc groove, 37-second convex structure. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] The embodiment of the present invention discloses a multimodal fingerprint acquisition and detection system, which is connected to a camera and includes: an image acquisition device, an OCT imaging device, and a high-resolution pressure acquisition device;

[0032] The image acquisition device is provided with a first imaging entrance 1, a second imaging entrance 2 and a camera entrance 3, wherein the first imaging entrance 1 and the second imaging entrance 2 are respectively arranged on two opposite sides of the image acquisition device, and the camera entrance 3 is arranged on a side surface between the sides where the first imaging entrance 1 and the second imaging entrance 2 are located; a rotatable double-sided reflector 4 is installed in the image acquisition device, wherein the two mirror surfaces of the rotatable double-sided reflector 4 correspond to the first imaging entrance 1 and the second imaging entrance 2 respectively, and the camera entrance 3 is arranged corresponding to the camera;

[0033] The OCT imaging device comprises a fiber coupler 5, a reference unit, a sample unit and an OCT image acquisition box 6; the reference unit, the sample unit and the OCT image acquisition box 6 are all connected to the fiber coupler 5, a first image acquisition port 7 on the OCT image acquisition box 6 is arranged corresponding to the first imaging entrance 1, and a first sample port 8 is arranged on the sample unit;

[0034] The second image acquisition port 9 on the high-resolution pressure acquisition device is arranged correspondingly to the second imaging inlet 2 . The high-resolution pressure acquisition device is also provided with a second sample port 10 . The first sample port 8 and the second sample port 10 are arranged correspondingly.

[0035] It should be noted that:

[0036] The optical fiber coupler 5 collects the optical signals reflected back by the sample unit and the reference unit, performs superposition and interference, and then sends the optical signals into the image acquisition device through the OCT image acquisition box 6. The rotatable double-sided reflector 4 is rotated to reflect the optical signals to the camera port 3 through the rotatable double-sided reflector 4 and send them to the camera for imaging. Specifically, when the light enters from the second imaging entrance 2, the rotatable double-sided reflector 4 is rotated in a direction away from the second imaging entrance 2 so that all the incoming light can be reflected to the camera port 3 and thus sent to the camera for imaging. When the light enters from the first imaging entrance 1, the rotatable double-sided reflector 4 is rotated in a direction away from the first imaging entrance 1 so that all the incoming light can be reflected to the camera port 3 and thus sent to the camera for imaging.

[0037] In order to further implement the above technical solution, a first arc-shaped groove 11 is arranged on the top surface of the image acquisition device, and a first protruding structure 12 is arranged on the upper edge of the rotatable double-sided reflector 4 and passes through the first arc-shaped groove 11, and the rotation of the rotatable double-sided reflector 4 in the image acquisition device is controlled by the first protruding structure 12.

[0038] In order to further implement the above technical solution, the reference unit, the sample unit and the OCT image acquisition box 6 are all connected to the fiber coupler 5 via optical fibers.

[0039] In order to further implement the above technical solution, the OCT imaging device further includes a broadband light source 13 , and the broadband light source 13 is connected to the optical fiber coupler 5 via an optical fiber.

[0040] In order to further implement the above technical solution, the reference unit includes a first box body 14, a first light-through hole 15 is arranged on the side of the first box body 14, and the interior of the first box body 14 includes a first convex lens 16, a lens, a second convex lens 18 and a first reflecting galvanometer 19; the first convex lens 16 is arranged correspondingly at the first light-through hole 15, and the first convex lens 16, the lens, the second convex lens 18 and the first reflecting galvanometer 19 are arranged in parallel in sequence.

[0041] In order to further realize the above technical solution, the sample unit includes a second box body 20, a second light hole 21 is arranged on the side of the second box body 20, a first sample port 8 is arranged on the opposite side of the second light hole 21, and the interior of the second box body 20 includes a third convex lens 22, a second reflecting galvanometer 23, a scanning galvanometer 24 and a fourth convex lens 25 in sequence; the third convex lens 22 is arranged correspondingly at the second light hole 21, the second reflecting galvanometer 23 and the third convex lens 22 are arranged correspondingly at an angle, the scanning galvanometer 24 is parallel to the second reflecting galvanometer 23, and the fourth convex lens 25 is arranged correspondingly to the scanning galvanometer 24; the first sample port 8 and the fourth convex lens 25 are arranged correspondingly.

[0042] In order to further implement the above technical solution, a third light through hole 26 is provided on the OCT image acquisition box 6, and a first image acquisition port 7 is provided on the opposite side of the third light through hole 26. The OCT image acquisition box 6 includes a fifth convex lens 27, a grating 28 and a sixth convex lens 29; the fifth convex lens 27 is correspondingly arranged at the third light through hole 26, the grating 28 is arranged between the fifth convex lens 27 and the sixth convex lens 29, and the first image acquisition port 7 and the sixth convex lens 29 are correspondingly arranged.

[0043] It should be noted that:

[0044] The high-resolution pressure acquisition device includes an optical channel body 30, a diffuser plate 31, a seventh convex lens 32 and a third box body 33; a light source entrance 34 is provided at one end of the optical channel body 30, the diffuser plate 31 is movably arranged inside the optical channel body 30, and the seventh convex lens 32 is arranged in a position away from the light source entrance 34 in the optical channel body 30; the third box body 33 is communicated with the optical channel body 30, a second sample port 10 is arranged on the side of the third box body 33, a second image acquisition port 9 is arranged on the opposite surface, transparent glass is arranged on the second sample port 10, a pressure strain gauge is arranged between the transparent glass and the second sample port 10, and a rotatable half mirror 35 is arranged inside the third box body 33; and a second arc groove 36 is arranged on the top surface of the third box body 33, a second convex structure 37 is arranged on the upper edge of the rotatable half mirror 35, and the second convex structure 37 passes through the second arc groove 36.

[0045] A multimodal fingerprint collection and detection method, comprising the following contents:

[0046] The light enters the reference unit and the sample unit respectively through the fiber coupler 5, and the reference unit reflects the light into the fiber coupler 5. The light entering the sample unit irradiates the sample through the first sample port 8, and is reflected into the sample unit again and further reflected into the fiber coupler 5. The fiber coupler 5 further superimposes and interferes the light signals reflected back from the sample unit and the reference unit, and then sends them into the image acquisition device through the first image acquisition port 7 on the OCT image acquisition box 6. The rotatable double-sided reflector 4 is rotated to reflect the light signal through the rotatable double-sided reflector 4 to the camera port 3 and send it to the camera for imaging.

[0047] The high-resolution pressure acquisition device collects the light reflected by the sample to the second image acquisition port 9, and further sends it into the image acquisition device through the second imaging port 2, rotates the rotatable double-sided reflector 4, and reflects the light signal through the rotatable double-sided reflector 4 to the camera port 3 and sends it to the camera for imaging.

[0048] In order to further implement the above technical solution, the path of the light in the reference unit is: the light enters the first box 14 from the first light hole 15 and passes through the first convex lens 16, the lens and the second convex lens 18 in sequence to the first reflecting galvanometer 19, is reflected by the first reflecting galvanometer 19 to the second convex lens 18, and then passes through the lens and the first convex lens 16 in sequence, and returns to the fiber coupler 5.

[0049] In order to further realize the above technical solution, the path of light in the sample unit is as follows: the light enters the second box body 20 from the second light hole 21 and passes through the third convex lens 22, the second reflecting galvanometer 23, the scanning galvanometer 24 and the fourth convex lens 25 in sequence, and passes through the first sample port 8 to irradiate the sample. After being reflected by the sample, the light returns to the sample unit again, and passes through the fourth convex lens 25, the scanning galvanometer 24, the second reflecting galvanometer 23 and the third convex lens 22 in sequence, and then enters the fiber coupler 5 through the second light hole 21.

[0050] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0051] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A multimodal fingerprint collection and detection system, connected to a camera, characterized in that: include: Image acquisition device, OCT imaging device and high-resolution pressure acquisition device; The image acquisition device is provided with a first imaging entrance (1), a second imaging entrance (2) and a camera entrance (3), wherein the first imaging entrance (1) and the second imaging entrance (2) are respectively arranged on two opposite side surfaces of the image acquisition device, and the camera entrance (3) is arranged on a side surface between the side surfaces where the first imaging entrance (1) and the second imaging entrance (2) are located; a rotatable double-sided reflector (4) is installed in the image acquisition device, wherein two mirror surfaces of the rotatable double-sided reflector (4) correspond to the first imaging entrance (1) and the second imaging entrance (2) respectively, and the camera entrance (3) is arranged corresponding to the camera; The OCT imaging device comprises a fiber coupler (5), a reference unit, a sample unit and an OCT image acquisition box (6); the reference unit, the sample unit and the OCT image acquisition box (6) are all connected to the fiber coupler (5); a first image acquisition port (7) on the OCT image acquisition box (6) is arranged corresponding to the first imaging entrance (1); and a first sample port (8) is arranged on the sample unit; The second image acquisition port (9) on the high-resolution pressure acquisition device is arranged correspondingly to the second imaging inlet (2), the high-resolution pressure acquisition device is also provided with a second sample port (10), and the first sample port (8) and the second sample port (10) are arranged correspondingly; The reference unit comprises a first box (14), a first light-through hole (15) is arranged on a side surface of the first box (14), and the interior of the first box (14) comprises a first convex lens (16), a lens (17), a second convex lens (18) and a first reflective galvanometer (19); the first convex lens (16) is arranged correspondingly at the first light-through hole (15), and the first convex lens (16), the lens (17), the second convex lens (18) and the first reflective galvanometer (19) are arranged in sequence and in parallel; The sample unit comprises a second box body (20), a second light-through hole (21) is arranged on a side surface of the second box body (20), a first sample port (8) is arranged on a side surface opposite to the second light-through hole (21), and the interior of the second box body (20) comprises a third convex lens (22), a second reflective galvanometer (23), a scanning galvanometer (24) and a fourth convex lens (25) in sequence; the third convex lens (22) is arranged correspondingly at the second light-through hole (21), the second reflective galvanometer (23) and the third convex lens (22) are arranged obliquely correspondingly, the scanning galvanometer (24) and the second reflective galvanometer (23), and the fourth convex lens (25) and the scanning galvanometer (24) are arranged correspondingly; the first sample port (8) and the fourth convex lens (25) are arranged correspondingly.

2. A multimodal fingerprint collection and detection system according to claim 1, characterized in that: A first arc-shaped groove (11) is arranged on the top surface of the image acquisition device, a first protruding structure (12) is arranged on the upper edge of the rotatable double-sided reflector (4) and passes through the first arc-shaped groove (11), and the rotation of the rotatable double-sided reflector (4) in the image acquisition device is controlled by the first protruding structure (12).

3. A multimodal fingerprint collection and detection system according to claim 1, characterized in that: The reference unit, the sample unit and the OCT image acquisition box (6) are all connected to the optical fiber coupler (5) via optical fibers.

4. The multimodal fingerprint collection and detection system according to claim 1, characterized in that: The OCT imaging device also includes a broadband light source (13), and the broadband light source (13) is connected to the optical fiber coupler (5) via an optical fiber.

5. The multimodal fingerprint collection and detection system according to claim 1, characterized in that: The OCT image acquisition box (6) is provided with a third light through hole (26), and a first image acquisition port (7) is provided on the opposite side of the third light through hole (26). The OCT image acquisition box (6) includes a fifth convex lens (27), a grating (28) and a sixth convex lens (29); the fifth convex lens (27) is arranged correspondingly at the third light through hole (26), the grating (28) is arranged between the fifth convex lens (27) and the sixth convex lens (29), and the first image acquisition port (7) and the sixth convex lens (29) are arranged correspondingly.

6. A multimodal fingerprint collection and detection method, characterized in that: Includes the following: Light enters the reference unit and the sample unit respectively through the optical fiber coupler (5), and the reference unit reflects the light back into the optical fiber coupler (5). The light entering the sample unit irradiates the sample through the first sample port (8), and is reflected back into the sample unit and further reflected into the optical fiber coupler (5). The optical fiber coupler (5) further superimposes and interferes the light signals reflected back from the sample unit and the reference unit, and then sends them into the image acquisition device through the first image acquisition port (7) on the OCT image acquisition box (6). The rotatable double-sided reflector (4) is rotated to reflect the light signal through the rotatable double-sided reflector (4) to the camera port (3) and send it to the camera for imaging. The high-resolution pressure acquisition device acquires the light reflected by the sample to the second image acquisition port (9), and further sends the light into the image acquisition device through the second imaging port (2), rotates the rotatable double-sided reflector (4), and reflects the light signal through the rotatable double-sided reflector (4) to the camera port (3) and sends the light signal to the camera for imaging; The path of the light in the reference unit is as follows: the light enters the first housing (14) from the first light hole (15) and passes through the first convex lens (16), the lens (17) and the second convex lens (18) in sequence to the first reflection galvanometer (19), is reflected by the first reflection galvanometer (19) to the second convex lens (18), then passes through the lens (17) and the first convex lens (16) in sequence, and returns to the optical fiber coupler (5); The path of the light in the sample unit is as follows: the light enters the second housing (20) from the second light through hole (21) and passes through the third convex lens (22), the second reflective galvanometer (23), the scanning galvanometer (24) and the fourth convex lens (25) in sequence, and passes through the first sample port (8) to irradiate the sample. After being reflected by the sample, the light returns to the sample unit again, and passes through the fourth convex lens (25), the scanning galvanometer (24), the second reflective galvanometer (23) and the third convex lens (22) in sequence, and then enters the optical fiber coupler (5) through the second light through hole (21).

Images