Panoramic imaging device and method for visualizing sample surface during pressing process

Abstract

The present invention discloses a panoramic imaging device for visualizing the surface of a sample during a pressing process, comprising a frame housing and an illumination light source assembled in the frame housing, a camera, a beam splitter prism, a first reflector, a collimating lens, an open parabolic reflector, a hyperbolic reflector, a transparent sample stage and a reflector group; the camera is assembled on one side of the beam splitter prism; the first reflector is assembled on the other side of the beam splitter prism and is used to reflect transmitted light in a vertical direction; the collimating lens and the hyperbolic reflector are assembled in sequence directly above the first reflector; the open parabolic reflector is assembled between the hyperbolic reflector and the collimating lens and is used to convert reflected light into parallel light for emission; the transparent sample stage is assembled directly above the hyperbolic reflector and is used to place a sample to be tested; the reflector group is assembled above the transparent sample stage and is used to reflect parallel light onto the surface of the sample to be tested; the imaging method thereof realizes all-round recording of the sample surface during the pressing or impact process.

Description

Technical Field

[0001] The present invention relates to the field of light reflection real-time imaging, and in particular to a panoramic imaging device and method for visualizing a sample surface during a pressing process. Background Art

[0002] Material mechanical properties testing technology bridges the gap between materials science and engineering applications. It not only impacts the safety of human life and property but also drives technological innovation and industrial upgrading. Over the past three decades, instrumented indentation testing has rapidly developed. This surface micro-area, non-destructive / mini-destructive, in-situ testing technique provides a simple and efficient means for evaluating the comprehensive response of a material's mechanical behavior.

[0003] Observation of the surface morphology of loaded samples is an important part of instrumented indentation experiments. Observing the surface of loaded specimens helps to deeply understand the mechanical behavior of materials and is of great significance to material performance evaluation, microstructure analysis, failure mechanism research, etc. Due to the influence of the indenter obstruction, it is very difficult to observe the dynamic changes of the specimen surface when it is under pressure. After the indentation experiment, observing the surface morphology of the specimen with an optical microscope is currently a more common observation method. This method can only observe the changes on the specimen surface after the indentation is completed, and the dynamic changes on the specimen surface during the indentation process cannot be observed and recorded in real time. Some scholars tilt the microscope at a certain angle to observe the surface of the loaded specimen. Although this can observe and record the changes on the surface of the loaded specimen, part of the specimen surface will be obscured by the indenter during the indentation process. Therefore, it is impossible to achieve a truly all-round observation.

[0004] In the "Full-field statistical characterization method for alloy microstructure by fluid micro-strain detection" disclosed in publication number CN107748173A, a white light interferometer is mainly used to scan the sample multiple times before and after the experiment to obtain the morphological changes on the surface of the alloy sample. The morphological changes before and after the sample are then quickly characterized across scales by quantitative statistical distribution to obtain a full-field metallographic map. This method does not truly achieve real-time observation and dynamic recording of the sample during the experiment.

[0005] In the "In-situ Tracking Metallographic Analysis Method for Steel Microstructural Evolution" (publication number CN102879330A), the analysis method relies on multiple metallographic observations and photographs to obtain a complete metallographic image of the target area, thereby performing in-situ tracking and metallographic analysis of the steel's microstructural evolution. This method does not truly achieve real-time dynamic recording of the sample's microstructural evolution. Its cumbersome experimental steps and high requirements for sample surface smoothness not only increase the complexity of the operation but also significantly prolong the experimental time. Summary of the Invention

[0006] In order to overcome the above-mentioned defects in the prior art, a panoramic imaging device and method for visualizing the sample surface during the pressing process are provided.

[0007] The technical solution of the present invention is as follows: a panoramic imaging device for visualizing the surface of a sample during the pressing process, comprising a frame housing and an illumination light source assembled in the frame housing, a camera, a beam splitter prism, a first reflector, a collimating lens, an open parabolic reflector, a hyperbolic reflector, a transparent sample stage and a reflector group; the camera is assembled on one side of the beam splitter prism; the first reflector is assembled on the other side of the beam splitter prism, and is used to reflect the transmitted light in a vertical direction; the collimating lens and the hyperbolic reflector are assembled in sequence directly above the first reflector; the open parabolic reflector is assembled between the hyperbolic reflector and the collimating lens, and is used to convert the reflected light into parallel light for emission; the transparent sample stage is assembled directly above the hyperbolic reflector, and is used to place the sample to be tested; the reflector group is assembled above the transparent sample stage, and is used to reflect the parallel light to the surface of the sample to be tested.

[0008] Preferably, the reflector group includes a plurality of square reflectors that are evenly distributed circumferentially around the transparent sample stage.

[0009] Preferably, the reflector group is mounted on the inner wall of the frame shell, and each of the plurality of square reflectors is provided with a rotating fixing member for changing the angle of the square reflector.

[0010] Preferably, the collimating lens is externally equipped with a fixing shell for fixing the collimating lens, and the size of the opening at the upper end of the fixing shell matches the size of the opening at the lower end of the open parabolic reflector.

[0011] Preferably, the rack shell includes an upper shell, a middle shell and a lower shell; the transparent sample table is assembled between the upper shell and the middle shell, and the lower shell is assembled at the lower end of the middle shell.

[0012] Preferably, the illumination light source, the camera and the dichroic prism are all assembled at the bottom of the lower housing.

[0013] Preferably, a rotating device for moving the position of the upper shell is provided between the middle shell and the upper shell; the rotating device includes a support connecting frame, a connecting rod and a pin, one end of the connecting rod is connected to the upper end of the upper shell by a pin, and the other end of the connecting rod is connected to the support connecting frame by a pin, and the support connecting frame is fixed to the outer wall of the middle shell.

[0014] Preferably, a through hole is provided at the center of the top end of the upper shell, and the through hole is used to allow the indenter to pass through and contact the surface of the sample to be tested during the indentation test.

[0015] Preferably, the hyperbolic reflective mirror is fixed at the lower end of the transparent sample stage.

[0016] Preferably, a groove for placing the sample to be tested is provided on the transparent sample table.

[0017] Panoramic imaging method for visualizing the specimen surface during indentation:

[0018] S1. Place the sample to be tested on the transparent sample table;

[0019] S2. After the parallel light emitted by the illumination light source is incident on the beam splitter prism, part of the incident light will be emitted into the first reflector. According to the placement of the first reflector, the outgoing light will be incident vertically upwards into the collimating lens;

[0020] S3. After being emitted from the collimating lens, the light will continue to propagate to the hyperbolic reflector reflective film layer where the hyperbolic reflector is located, and will be further reflected to the parabolic reflector reflective film layer of the open parabolic reflector. After being reflected by the parabolic reflector reflective film layer, the light will be reflected along the vertical direction to the reflector group.

[0021] S4. Finally, the light is incident on the surface of the sample to be tested. When the light hits the rough surface of the sample, the tiny irregular structures on the surface cause the light to scatter in multiple directions, thereby generating diffuse reflection. There are some diffusely reflected lights at specific angles. These diffusely reflected lights are incident on the square reflector and will be reflected by the square reflector to the inner surface of the open parabolic reflector. Then, they are incident on the camera through the subsequent collimating lens, the first reflector and the dichroic prism.

[0022] S5. The camera captures the diffusely reflected light containing the sample information transmitted in the reverse direction and performs real-time imaging and recording, thereby being able to record the changes of the sample during the pressing process in real time and intuitively.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] This invention utilizes a single camera combined with a special optical design to achieve omnidirectional imaging of the dynamic changes in the sample surface during the indentation process, providing technical support for in-depth research into material failure mechanisms, mechanical behavior, and performance. Furthermore, the incident light fully covers the loaded surface area of ​​the sample, and the light contacts the sample surface and undergoes diffuse reflection. The camera then records the reflected light in real time, allowing for more intuitive and clear observation of changes in the surface of the test sample during the indentation process. This device utilizes panoramic imaging technology to provide a 360-degree viewing angle for the sample surface during the indentation process, without being restricted by the indenter geometry, sample shape, or size.

[0025] Furthermore, by arranging a reflector assembly and an open parabolic reflector, the present invention can reflect parallel light at a specific angle onto the sample surface, receive diffusely reflected light from the sample surface, and convert it into parallel light for the camera to capture. This design not only simplifies the imaging system but also improves imaging efficiency.

[0026] Furthermore, the frame housing of the present invention adopts a layered design, which is convenient for disassembly and maintenance. At the same time, the design of the rotating device allows the upper housing to rotate around the axis of the connecting rod, which is convenient for placing and removing samples.

[0027] Furthermore, the present invention provides a groove on the transparent sample table to facilitate the placement and fixation of the cylindrical sample. At the same time, the rotating fixing member on the reflector assembly can adjust the angle of the square reflector to meet the observation requirements of different samples.

[0028] Furthermore, the present invention can not only be used as an additional device for the indentation test, but can also be used in tests such as impact tests where the sample surface is blocked or partially blocked, to observe the deformation and damage of the sample during the stress process, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention will be further described below with reference to the accompanying drawings:

[0030] Figure 1 Schematic diagram of the structure of the panoramic imaging device of the present invention;

[0031] Figure 2 It is a schematic diagram of the device structure in the rack housing of the present invention;

[0032] Figure 3 This is a schematic diagram of the catadioptric imaging principle of the present invention;

[0033] Figure 4 This is a schematic diagram of the coaxial optical path of the camera and illumination light source of the present invention;

[0034] Figure 5 is an optical schematic diagram of the focus of the collimating lens of the present invention;

[0035] Figure 6 is a schematic diagram of a reflective film layer of a hyperbolic reflector according to the present invention;

[0036] Figure 7 Schematic diagram of the structure of the open parabolic reflector of the present invention;

[0037] Figure 8 Schematic diagram of the focal position between the collimating lens and the hyperbolic reflector of the present invention;

[0038] Figure 9Schematic diagram of the position of the focus B of the open parabolic reflector of the present invention;

[0039] The following are the descriptions of the reference numerals:

[0040] Rack housing 1, illumination light source 2, camera 3, dichroic prism 4, first reflector 5, collimating lens 6, open parabolic reflector 7, parabolic reflector reflective film layer 71, connecting hole 72, hyperbolic reflector 8, hyperbolic reflector reflective film layer 81, transparent sample stage 9, reflector group 10, square reflector 101, rotating fixture 1011, fixed shell 61, upper shell 11, middle shell 12, lower shell 13, rotating device 111, supporting connecting frame 1111, connecting rod 1112, pin 1113, through hole 112, groove 91. DETAILED DESCRIPTION

[0041] The following is an explanation and description of the technical solutions of the embodiments of the present invention in conjunction with the drawings of the embodiments of the present invention. However, the following embodiments are only preferred embodiments of the present invention and are not exhaustive. Based on the embodiments in the implementation manner, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention.

[0042] In the following description, terms such as "inside", "outside", "up", "down", "left", "right", etc. that indicate directions or positional relationships are only used to facilitate the description of the embodiments and simplify the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operate in a specific direction. Therefore, they should not be understood as limiting the present invention.

[0043] like Figures 1 to 9 As shown in FIG, the panoramic imaging device for visualizing the sample surface during the pressing process mainly includes a housing 1 and various components assembled within the housing 1. The housing 1 is composed of an upper housing 11, a middle housing 12, and a lower housing 13, forming a stable and closed structure. At the bottom of the lower housing 13, we have assembled an illumination source 2, a camera 3, and a beam splitter prism 4. Figure 4 As shown, the illumination light source 2 is used to provide sufficient light to illuminate the sample to be tested, the camera 3 is used to capture and record the light information after reflection and refraction, and the beam splitter prism 4 plays the role of dividing the incident light into transmitted light and reflected light.

[0044] The first reflector 5 is mounted on the other side of the beam splitter prism 4. Its main function is to reflect the transmitted light in the vertical direction. Next, the collimating lens 6 and the hyperbolic reflector 8 are mounted in sequence directly above the first reflector 5. The collimating lens 6 is used to converge the reflected light to a focal point, while the hyperbolic reflector 8 further reflects the converged light and makes its extended line converge at another focal point. In order to achieve this function; Figure 6As shown, the outer surface of the hyperbolic reflector 8 at the vertex thereof is plated with a hyperbolic reflector reflective film layer 81 .

[0045] Directly above the hyperbolic reflector 8, we installed a transparent sample stage 9 for placing the sample to be tested. The transparent sample stage 9 is provided with a groove 91 to facilitate the placement and fixation of the cylindrical sample. Above the transparent sample stage 9, we installed a reflector group 10. The reflector group 10 consists of a number of square reflectors 101 uniformly distributed circumferentially with the transparent sample stage 9 as the center. Each square reflector 101 is provided with a rotating fixture 1011 for changing the angle of the square reflector 101. The main function of the reflector group 10 is to reflect parallel light to the sample surface at a specific angle, receive diffusely reflected light from the sample surface, and then reflect it to the open parabolic reflector 7.

[0046] The open parabolic reflector 7 is mounted between the hyperbolic reflector 8 and the collimating lens 6; Figure 7 As shown, its inner surface is coated with a parabolic reflective film layer 71. The main function of the open parabolic reflector 7 is to convert reflected light into parallel light for capture by the camera 3. To ensure stable assembly, the bottom of the open parabolic reflector 7 is provided with a connection hole 72 to facilitate fixing to the fixed housing 61 or other connecting components.

[0047] Furthermore, a rotation mechanism 111 is provided between the middle shell 12 and the upper shell 11, for adjusting the position of the upper shell 11. This mechanism comprises a support bracket 1111, a connecting rod 1112, and a pin 1113. One end of the connecting rod 1112 is connected to the upper end of the upper shell 11 via the pin 1113, while the other end is connected to the support bracket 1111 via the pin 1113. The support bracket 1111 is fixed to the outer wall of the middle shell 12. This design allows the upper shell 11 to rotate a certain angle around the axis of the connecting rod 1112, facilitating the placement and removal of specimens.

[0048] Specifically, the supporting connecting frame 1111 is "L"-shaped.

[0049] A through-hole 112 is provided at the top center of the upper shell 11 to allow the indenter to pass through and contact the sample surface during the indentation test. This design allows the present invention to be used not only to observe the surface morphology of the sample, but also to perform indentation tests to observe the deformation and damage of the sample during the stress process.

[0050] This panoramic imaging device can not only be used to observe the surface morphology of the test sample, but also can be used in experiments where the sample surface is blocked or partially blocked during tests such as indentation and impact. By observing and recording the sample in real time during the experiment, the deformation and damage of the test sample during the stress process can be grasped in real time, so it has broad application prospects.

[0051] Specifically, Figure 1 and Figure 2 The dichroic prism 4 in the figure is used as the starting point to establish the spatial coordinate system shown in the figure. The plane of the dichroic prism 4 coated with a semi-transmissive and semi-reflective film layer is obtained by rotating the XZ plane 45° counterclockwise around the Z axis. The spatial coordinates of the illumination light source 2 can be obtained by moving the spatial coordinates of the dichroic prism 4 along the positive direction of the Y axis by a certain distance. After the light emitted by the illumination light source 2 is incident on the dichroic prism 4, part of the light is transmitted and will propagate along the left end of the dichroic prism to the next optical element, that is, propagating along the negative direction of the Y axis; part of the light is incident on the inclined surface and will be reflected along the negative direction of the X axis. This part of the reflected light can be ignored for the entire optical path. The spatial coordinates of the camera 3 can be obtained by moving the spatial coordinates of the dichroic prism 4 along the positive direction of the X axis by a certain distance. The illumination light source 2, camera 3, and dichroic prism 4 are placed on the same plane, which greatly reduces the volume occupied by the entire device in the vertical direction.

[0052] The spatial coordinates of the first reflector 5 can be obtained by moving the spatial coordinates of the beam splitter prism 4 a certain distance along the negative direction of the Y axis, and the plane where the first reflector 5 is located is obtained by rotating the XZ plane 45° counterclockwise around the X axis. The surface of the first reflector 5 coated with the reflective film is opposite to the exit surface of the beam splitter prism 4. Therefore, the light emitted by the illumination light source 2 passes through the beam splitter prism 4 and is emitted onto the reflective film of the first reflector 5. The light will continue to propagate in the vertical direction, that is, the positive direction of the Z axis.

[0053] The collimating lens 6 is located directly above the first reflector 5, that is, at a certain distance along the positive direction of the Z axis. The collimating lens 6 is a plano-convex lens, which is vertically embedded in the fixed housing 61. Its convex surface is the incident surface of the light, and the flat surface is the exit surface. The light emitted by the illumination light source 2 passes through the beam splitter prism 4 and is emitted onto the reflective film layer of the first reflector 5. The light will continue to propagate in the vertical direction to the collimating lens 6. Affected by the placement of the collimating lens 6, the light will converge at the focus of the collimating lens (such as Figure 5 As shown) Here the focus of the collimating lens is denoted as A.

[0054] The upper end of the fixed shell 61 is connected to the lower end of the open parabolic reflector 7 , and the illumination light source 2 , the camera 3 , the beam splitter prism 4 , and the first reflector 5 are all placed inside the lower shell 13 of the rack.

[0055] in, Figure 5Schematic diagram of light converging at point A after passing through the collimating lens; Figure 8 The image of a hyperbola is also called the vertical axis hyperbola. In mathematical geometry, a hyperbola has two segments in a rectangular coordinate system, which can be recorded as the upper branch X1 and the lower branch X2 of the hyperbola. The hyperbolic reflector in the imaging device is composed of Figure 8 The upper branch X1 of the hyperbola in the figure is rotated 180 degrees around the X-axis. C1 is the focus of the upper branch of the hyperbola, and C2 is the focus of the lower branch of the hyperbola. Figure 9 is the image of a parabola, which is Figure 9 The middle mark is Y1, the parabola in the figure is not a complete parabola, and B is the geometric focus of the parabola. The parabolic reflector in the imaging device is composed of Figure 9 The parabola in the figure is rotated 180 degrees around the Y axis to form a hollow shape.

[0056] like Figure 5 、 Figure 8 and Figure 9 As shown, the hyperbolic reflector 8 in the present device is obtained by rotating the upper branch X1 of the hyperbola 180° around the X-axis of the plane coordinate system, and the outer surface where the vertex is located is coated with a hyperbolic reflector reflective film layer 81. The hyperbolic reflector 8 is located directly above the collimating lens 6. A certain positional relationship needs to be maintained between the collimating lens and the hyperbolic reflector. The focus C2 of the lower branch X2 of the hyperbola should coincide with the focus A of the collimating lens 6. From the knowledge of geometric optics, it can be known that parallel light is incident on the collimating lens 6 and will converge at its focus A. The focus C2 of the lower branch X2 of the hyperbola coincides with the focus A of the collimating lens, so the parallel light will converge at the focus C2 of the lower branch of the hyperbola, and the converged light will continue to propagate to the reflecting surface formed by the upper branch X1 of the hyperbola. After reflection, the reverse extension line of the outgoing light will converge at the focus C1 of the upper branch X1 of the hyperbola. The surface away from the vertex of the hyperbolic reflector 8 is connected to the lower end of the transparent sample table 9.

[0057] The inner surface of the open parabolic reflector 7 is coated with a parabolic reflector reflective film layer 71, and the remaining surfaces do not need to be coated. The open parabolic reflector 7 is placed between the collimating lens 6 and the hyperbolic reflector 8. If the geometric focus of the open parabolic reflector 7 is recorded as B, it is necessary to ensure that the focus B of the open parabolic reflector 7 and the focus C1 of the hyperbola upper branch X1 of the hyperbolic reflector 8 coincide with each other. After the light is reflected by the outer surface of the hyperbolic reflector, it will be incident on the inner surface of the open parabolic reflector 7. After being reflected by the parabolic reflector, it will be emitted in the vertical direction, that is, the positive direction of the Z axis. Here, the propagation of the light path satisfies a certain geometric relationship. After the light propagated from the collimating lens is reflected by the outer surface of the hyperbolic reflector, the reverse extension line of the reflected light will converge at the focus C1. The geometric focus B of the open parabolic reflector 7 coincides with the focus C1 of the upper branch X1 of the hyperbola of the hyperbolic reflector 8. The light reflected by the hyperbolic reflector can be regarded as emitted from the parabola focus B. The reflected light will reach the inner surface of the parabolic reflector and, after reflection, will be emitted in the vertical direction.

[0058] The transparent sample stage 9 is located directly above the hyperbolic reflector 8, with its lower end in contact with the flat end of the hyperbolic reflector 8. The transparent sample stage 9 is made of transparent silicon dioxide and is in a "concave" shape, so light can pass through the transparent sample stage 9 smoothly. A groove 91 is provided in the center of the transparent sample stage 9, and a cylindrical sample can be placed in the middle part. The parallel light emitted by the open parabolic reflector can pass through the workbench smoothly to the next light element.

[0059] The reflector group 10 composed of a plurality of square reflectors 101 is placed inside the upper shell 11 of the rack, and the square reflectors 101 are distributed in a ring shape. The schematic diagram only shows a part of the square reflectors. The number of square reflectors 101 in the device should be determined according to the specific situation, and it is necessary to ensure that the output light of the reflector group can cover the entire sample pressing area. Among them, the square reflector can rotate around its constrained end at a certain angle, and the parallel light emitted by the open parabolic reflector 7 passes through the transparent sample table 9 and is incident on the square reflector group 10. The light will be emitted to the sample pressing area located at The angle at which light is incident on the sample surface on the transparent sample stage 9 can be adjusted by rotating each square reflector 101. After passing through the reflector group, the light will be incident on the sample surface at a certain angle and will be diffusely reflected on the sample surface. There are some diffusely reflected lights at specific angles. These diffusely reflected lights are incident on the square reflector 101 and will be vertically reflected to the inner surface of the open parabolic reflector 7. Then, they are incident on the camera 3 through subsequent optical elements. The camera captures the diffusely reflected light containing sample information transmitted in the reverse direction and performs real-time imaging and recording.

[0060] The upper shell 11 of the rack is connected to one end of the connecting rod 1112 by a pin 1113, and the other end of the connecting rod 1112 is connected to the support connecting frame 1111 by a pin 1113, and the support connecting frame 1111 is fixed to the middle shell 12 of the rack; when performing a press-in or impact test, if it is necessary to place a sample, it is only necessary to rotate the connecting rod 1112, and the connecting rod 1112 will drive the upper shell 11 of the rack to move in the XY plane, so that the sample can be placed in the transparent sample table 9. After the sample is placed, it is only necessary to turn the connecting rod 1112 back to its original position, and the indenter can pass through the through hole 112 at the upper end of the upper shell 11 of the rack to contact the surface of the sample, completing a normal press-in test.

[0061] Here is a complete description of the panoramic imaging method for visualizing the sample surface during the pressing process: After the parallel light emitted by the illumination light source 2 is incident on the beam splitter prism 4, part of the incident light will be emitted to the first reflector 5. Affected by the placement of the first reflector, the outgoing light will be incident vertically upward to the position of the collimating lens 6, as shown in FIG. Figure 3 As shown, after being emitted by the collimating lens 6, the light will continue to propagate to the outer surface of the hyperbolic reflector 8, and will be further reflected to the inner surface of the open parabolic reflector 7. After being reflected by the inner surface of the parabolic reflector reflective film layer 71, the light will be emitted in the vertical direction to the square reflector group 10, and finally be incident on the surface of the sample on the transparent sample table 9. When the light is irradiated on the rough surface of the sample, the tiny irregular structure on the surface causes the light to be scattered in multiple directions, thereby generating diffuse reflection, among which there are some diffusely reflected light rays at specific angles. These diffusely reflected light rays are incident on the square reflector 101, and will be reflected by the square reflector 101 to the inner surface of the open parabolic reflector 7, and then be incident on the camera 3 through subsequent optical elements. The camera 3 captures the diffusely reflected light containing the sample information transmitted in the reverse direction and performs real-time imaging and recording, so that the change process of the sample during the pressing process can be recorded in real time and intuitively.

[0062] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Those skilled in the art will understand that the present invention includes, but is not limited to, the contents described in the drawings and the above specific embodiments. Any modifications that do not deviate from the functional and structural principles of the present invention are intended to be included within the scope of the claims.

Claims

1. A panoramic imaging device for visualizing the sample surface during the pressing process, characterized by: The invention comprises a frame housing (1) and an illumination light source (2) assembled in the frame housing (1), a camera (3), a beam splitter prism (4), a first reflector (5), a collimating lens (6), an open parabolic reflector (7), a hyperbolic reflector (8), a transparent sample stage (9) and a reflector group (10); the camera (3) is assembled on one side of the beam splitter prism (4) for receiving and recording light information after reflection and refraction; the first reflector (5) is assembled on the other side of the beam splitter prism (4) for reflecting the transmitted light in a vertical direction; the collimating lens (6) and the hyperbolic reflector (8) are assembled in sequence directly above the first reflector (5); An open parabolic reflector (7) is mounted between a hyperbolic reflector (8) and a collimating lens (6) for converting reflected light into parallel light for emission; a transparent sample stage (9) is mounted directly above the hyperbolic reflector (8) for placing a sample to be tested; a reflector group (10) is mounted above the transparent sample stage (9) for reflecting parallel light onto the surface of the sample to be tested; a focus (C2) of the lower branch of the hyperbolic reflector (8) coincides with a focus (A) of the collimating lens (6), and a focus (B) of the open parabolic reflector (7) coincides with a focus (C1) of the upper branch of the hyperbolic reflector (8), thereby forming a confocal optical system.

2. The panoramic imaging device for visualizing the sample surface during the pressing process according to claim 1, characterized in that: The reflector assembly (10) comprises a plurality of square reflectors (101) uniformly distributed circumferentially around the transparent sample platform (9).

3. The panoramic imaging device for visualizing the sample surface during the pressing process according to claim 1, characterized in that: The reflector group (10) is assembled on the inner wall of the frame housing (1), and a plurality of square reflectors (101) are each provided with a rotating fixing member (1011) for changing the angle of the square reflectors (101).

4. The panoramic imaging device for visualizing the sample surface during the pressing process according to claim 1, characterized in that: The collimating lens (6) is externally equipped with a fixing shell (61) for fixing the collimating lens (6), and the size of the opening at the upper end of the fixing shell (61) matches the size of the opening at the lower end of the open parabolic reflector (7).

5. The panoramic imaging device for visualizing the sample surface during the pressing process according to claim 1, characterized in that: The frame housing (1) comprises an upper housing (11), a middle housing (12) and a lower housing (13); the transparent sample table (9) is assembled between the upper housing (11) and the middle housing (12), and the lower housing (13) is assembled at the lower end of the middle housing (12).

6. The panoramic imaging device for visualizing the sample surface during the pressing process according to claim 1, characterized in that: The illumination light source (2), camera (3) and beam splitter prism (4) are all assembled at the bottom of the lower shell (13).

7. The panoramic imaging device for visualizing the sample surface during the pressing process according to claim 5, characterized in that: A rotating device (111) for moving the position of the upper shell (11) is provided between the middle shell (12) and the upper shell (11); the rotating device (111) comprises a supporting connecting frame (1111), a connecting rod (1112) and a pin (1113); one end of the connecting rod (1112) is connected to the upper end of the upper shell (11) via the pin (1113); the other end of the connecting rod (1112) is connected to the supporting connecting frame (1111) via the pin (1113); and the supporting connecting frame (1111) is fixed to the outer wall of the middle shell (12).

8. The panoramic imaging device for visualizing the sample surface during the pressing process according to claim 5, characterized in that: A through hole (112) is provided at the center of the top end of the upper shell (11), and the through hole (112) is used to allow the indenter to pass through and contact the surface of the sample to be tested during the indentation test.

9. The panoramic imaging device for visualizing the sample surface during the pressing process according to claim 1, characterized in that: The hyperbolic reflector (8) is fixed to the lower end of the transparent sample table (9).

10. A panoramic imaging method for visualizing a sample surface during an indentation process, applicable to the panoramic imaging device for visualizing a sample surface during an indentation process according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1. Place the sample to be tested on the transparent sample table (9); S2, after the parallel light emitted by the illumination light source (2) is incident on the beam splitter prism (4), part of the incident light will be emitted into the first reflector (5), and according to the placement position of the first reflector (5), the emitted light will be incident vertically upward on the collimating lens (6); S3, the light emitted from the collimating lens (6) will continue to propagate to the hyperbolic reflector reflective film layer (81) where the hyperbolic reflector (8) is located, and will be further reflected to the parabolic reflector reflective film layer (71) of the open parabolic reflector (7), and after being reflected by the parabolic reflector reflective film layer (71), the light emitted in the vertical direction will be reflected to the reflector group (10); S4, finally incident on the surface of the sample to be tested. When the light hits the rough surface of the sample, the tiny irregular structures on the surface cause the light to scatter in multiple directions, thereby generating diffuse reflection, wherein there are some diffusely reflected light rays at specific angles. These diffusely reflected light rays are incident on the square reflector (101), and are reflected by the square reflector (101) to the inner surface of the open parabolic reflector (7), and then incident on the camera (3) through the subsequent collimating lens (6), the first reflector (5) and the dichroic prism (4); S5. The camera (3) captures the diffusely reflected light containing the sample information transmitted in the reverse direction and performs real-time imaging and recording, thereby being able to record the changes of the sample during the pressing process in real time and intuitively.

Images