Detection device based on double-line laser range finder and calibration mechanism thereof

Abstract

The utility model discloses a detection device based on a double-line laser range finder and a calibration mechanism thereof, and belongs to the technical field of optical vision measurement. According to the scheme, a calibration mechanism comprises a calibration plate and a fine adjustment mechanism, the calibration plate is located between the two correlation type line laser range finders, and at least one slit which penetrates through the calibration plate and can allow line laser to penetrate through is machined in the calibration plate; and the fine adjustment mechanism is used for adjusting the mounting angles of the two line laser range finders, so that the light rays emitted by the two line laser range finders pass through the same slit. The calibration mechanism is used for improving the installation centering precision of the correlation type double-line laser range finder, and the adjustment process of the calibration mechanism is simple and visual; the detection device adopting the calibration mechanism can accurately measure the object to be measured.

Description

Technical Field

[0001] This utility model relates to the field of optical vision measurement technology, and more specifically, to a detection device and calibration mechanism based on a line laser rangefinder. Background Technology

[0002] Ultrathin thickness measurement technology has important applications in many technological fields, especially in materials research and development, quality control, electronic product manufacturing, optical applications, environmental monitoring, and scientific research. By accurately measuring the thickness of ultrathin materials, it can be used to optimize material properties, improve product quality, enhance the reliability of electronic devices, optimize optical design, improve sensor sensitivity, and provide experimental data for basic scientific research.

[0003] Due to their ultra-thin physical properties, ultra-thin objects present numerous challenges in measurement, including: (1) Ultra-thin materials typically have low mechanical strength and are easily deformable. Traditional contact measurement methods may cause material damage or deformation, thus affecting the accuracy of the measurement results; (2) In micron- or nanometer-level thickness measurements, any tiny error can lead to significant deviations, thus requiring measurement equipment with extremely high resolution and stability; (3) The surface condition of ultra-thin materials, such as roughness and gloss, can affect laser reflection and interference effects, thereby affecting the measurement results. Therefore, appropriate surface treatment is required to ensure measurement accuracy; (4) Environmental factors such as temperature, humidity, and vibration may affect the measurement results, especially in the measurement of ultra-thin objects with high precision requirements. Therefore, measures need to be taken to reduce the impact of these factors.

[0004] To address the technical challenges of measuring the thickness of ultra-thin objects, the current mainstream measurement technology is ultrasonic thickness measurement. This measurement requires contact with the object being measured, which may cause damage. It is also highly sensitive to the acoustic properties of the material and has high requirements for surface conditions. Furthermore, it has limited resolution in micron-level thickness measurements.

[0005] For example, Chinese patent application CN101614533A discloses a method for accurately measuring the thickness of ultra-thin workpieces. This method uses signal processing technology to extract ultrasonic information characterizing the workpiece thickness and is applicable to the measurement of both ultra-thin, high-curvature workpieces and ordinary workpieces. The core technology is to perform a fast Fourier transform on the echo signal to obtain the measurement result. In addition, the instrument used consists of a probe and a main unit, which has the ability to acquire and calculate data in real time, thereby realizing mechanized and automatic measurement. However, this method has certain limitations on the material requirements of the workpiece; special materials cannot be detected, and the probe may damage the object being measured to some extent.

[0006] For example, patent CN218973412U relates to a non-invasive ultra-thin metal film thickness gauge, which includes a non-destructive probe and a series of high-frequency electronic components. Its features include high measurement accuracy and an intuitive operating interface. It is not affected by the surface covering of the metal film to be measured. However, the material it measures is also limited, and it cannot intuitively display the points and surfaces to be measured in a large area through a three-dimensional model.

[0007] With the development of measurement technology, optical vision inspection technology is increasingly being applied to the thickness measurement of ultra-thin materials. It has no limitations on the materials being measured and can display the points to be measured in the form of a three-dimensional model. A dual-line laser rangefinder is one of the important devices in optical vision inspection technology. Its core principle lies in the fact that a laser beam is shone onto the object being measured, and the result is fed back to the camera sensor. Based on the principle of line laser triangulation, the distance between the camera and the object can be accurately calculated, thereby determining the object's thickness.

[0008] Currently, the applications of line laser rangefinders are mostly focused on reconstructing 3D models of objects to detect defects; their application in measuring ultrathin materials still needs improvement. When using dual-line laser rangefinders for thickness measurement, assuming identical equipment performance, the relative accuracy of through-beam dual-line laser rangefinders significantly impacts measurement precision. The installation alignment accuracy of the dual-line laser rangefinder has a particularly significant impact, and research focusing on reducing errors caused by installation alignment accuracy through physical factors is relatively limited.

[0009] A search revealed Chinese patent application number 201710852102X, which discloses a positioning device and method for a camera and its through-beam laser sensor. The positioning device is positioned between two laser sensors and includes: a transparent calibration plate with positioning marks for positioning the two laser sensors on either side, allowing for initial alignment; and a positioning element for scanning by the two laser sensors to obtain the closest point on the positioning element to the corresponding laser sensor. Alignment is achieved when the distance between the two points obtained by the two laser sensors corresponds to the corresponding size of the positioning element. Using the calibration marks on the calibration plate as the reference coordinate origin for the upper and lower laser focal points and the camera center, a rough positioning is achieved by aligning the reference coordinate origin of the camera's image with the laser focal point. Then, the upper and lower laser displacement sensors scan the positioning element respectively. Alignment is achieved when the distance between the two points obtained by the two laser sensors is the same as the diameter of the positioning element, resulting in high positioning accuracy and improved production efficiency. This application uses a combination of hardware and software to adjust the alignment of the laser sensors, making the adjustment method relatively complex. Utility Model Content

[0010] To address the relatively complex installation, alignment, and adjustment issues of existing through-beam dual-line laser rangefinders, this invention provides a detection device and calibration mechanism based on a dual-line laser rangefinder. This solution optimizes the calibration mechanism of the dual-line laser rangefinder, improving the installation and alignment accuracy of the through-beam dual-line laser rangefinder from the perspective of physical influencing factors. Furthermore, the adjustment process of this calibration mechanism is simple and intuitive.

[0011] To achieve the above objectives, the technical solution provided by this utility model is as follows:

[0012] The first aspect of this utility model provides a calibration mechanism for a detection device based on a dual-line laser rangefinder, comprising: a calibration plate located between two through-beam line laser rangefinders, wherein the calibration plate is machined with at least one slit through which the line laser can pass; and a fine-tuning mechanism for adjusting the installation angle of the two line laser rangefinders so that the light emitted by the two line laser rangefinders passes through the same slit.

[0013] Furthermore, the width of the slit is greater than the diameter of the laser spot emitted by the line laser rangefinder; and / or the calibration plate is provided with multiple parallel slits with progressively increasing widths.

[0014] Furthermore, the length of the slit is greater than the projection width of the laser line emitted by the line laser rangefinder on the calibration plate.

[0015] Furthermore, two through-beam line laser rangefinders are symmetrically arranged on both sides of the same end of the mounting base, and a corresponding channel is provided on the mounting base between the two line laser rangefinders.

[0016] Furthermore, the fine-tuning mechanism includes a first adapter plate and a first adjustment plate. The first adapter plate is fixedly connected to the mounting base frame. The line laser rangefinder is mounted on the first adapter plate through the first adjustment plate. The first adapter plate is threaded with an adjustment screw for tightening the first adjustment plate to adjust the mounting angle of the first adjustment plate.

[0017] Furthermore, the number of adjusting set screws is four, and the four adjusting set screws are distributed along a ring interval on the first adapter plate to adjust the tilt angle between the adjacent surfaces of the first adjusting plate and the first adapter plate.

[0018] Furthermore, there are two fine-tuning mechanisms, which are respectively set on the diagonal of the rectangle formed by the first line laser rangefinder and the second line laser rangefinder.

[0019] The second aspect of this utility model provides a detection device based on a dual-line laser rangefinder, comprising two through-beam line laser rangefinders and the aforementioned calibration mechanism; the two through-beam line laser rangefinders and the calibration mechanism are all mounted on a mounting frame.

[0020] Compared with the prior art, the technical solution provided by this utility model has the following advantages:

[0021] (1) This utility model optimizes the design of the calibration mechanism of the dual laser rangefinder. The calibration mechanism includes a calibration plate with a slit and a fine-tuning mechanism. The slit serves as an alignment reference for the two dual laser rangefinders. The fine-tuning mechanism is used to adjust the installation angle of the two line laser rangefinders so that the laser lines emitted by the two line laser rangefinders pass through the same slit. This enables intuitive adjustment of the installation accuracy of the two line laser rangefinders, improves the installation alignment accuracy of the through-beam dual line laser rangefinder, and places the two line laser rangefinders in the same coordinate system, thereby achieving high-precision measurement of ultra-thin objects.

[0022] (2) This utility model further optimizes the design of the fine-tuning mechanism. Specifically, the fine-tuning structure includes a first adapter plate and a first adjustment plate. The line laser rangefinder is mounted on the mounting base frame via the first adjustment plate and the first adapter plate. The first adapter plate is threaded with adjusting screws for tightening the first adjustment plate and adjusting the mounting angle of the first adjustment plate. By adjusting the different heights of multiple adjusting screws in the first adapter plate, the distance between different points on the adjacent surfaces of the first adjustment plate and the first adapter plate is adjusted to have different distances, thereby adjusting the tilt angle between the adjacent surfaces of the first adjustment plate and the first adapter plate. This fine-tuning mechanism has a simple structure and is easy to adjust. Attached Figure Description

[0023] Figure 1 This is a three-dimensional structural diagram of the detection device based on a dual-line laser rangefinder in an embodiment of this utility model.

[0024] Figure 2 This is a three-dimensional structural diagram of the calibration mechanism in an embodiment of this utility model.

[0025] Figure 3 This is a three-dimensional structural diagram of the calibration mechanism from another perspective in an embodiment of this utility model.

[0026] Figure 4 This is a partial three-dimensional structural diagram of the calibration mechanism in an embodiment of this utility model.

[0027] Label Explanation:

[0028] 1. Calibration mechanism; 101. Calibration plate; 1011. Gap; 1012. Calibration surface; 102. First adjustment plate; 103. First adapter plate; 1031. Connecting screw; 1032. Adjusting set screw; 104. Third adapter plate; 1041. Calibration plate connecting hole; 105. Second adjustment plate; 106. Second adapter plate;

[0029] 2. First-line laser rangefinder;

[0030] 3. Second-line laser rangefinder;

[0031] 4. Install the base frame. Detailed Implementation

[0032] To further understand the content of this utility model, a detailed description of this utility model will be provided in conjunction with the accompanying drawings and embodiments.

[0033] The structures, proportions, and sizes illustrated in the accompanying drawings are merely for illustrative purposes and to aid those skilled in the art in understanding and reading the invention. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of the invention, should still fall within the scope of the technical content disclosed in this utility model. Furthermore, terms such as "upper," "lower," "left," "right," and "middle" used in this specification are merely for clarity and not intended to limit the scope of implementation. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention's implementation.

[0034] Explanation of names in this specific implementation: (The rest of the text is a list of names and their meanings.) Figure 4 Taking the perspective of [reference needed], the width of slit 1011 refers to "the distance between its upper and lower planes within slit 1011", the length of slit 1011 refers to "the distance between its left and right ends within slit 1011", and the depth of slit 1011 is "the dimension of slit 1011 in the calibration plate 101 along the direction of the line connecting the two line laser rangefinders", and the length of slit 1011 is much greater than its width. The projection width of the line laser rangefinder refers to the dimension of the projection of the line laser emitted by the first line laser rangefinder 2 or the second line laser rangefinder 3 in the calibration plate 101 along the length direction of slit 1011.

[0035] This embodiment provides a detection device and calibration mechanism for a dual-line laser rangefinder, with reference to... Figure 1 , Figure 2 As shown, it includes two through-beam line laser rangefinders and a calibration mechanism 1; both through-beam line laser rangefinders and the calibration mechanism 1 are mounted on the mounting base 4.

[0036] Preferably, the mounting base frame 4 is a rectangular frame with one open end. More preferably, the two long sides of the rectangular frame are constructed from profiles, which have high precision and are suitable as mounting bases. One short side of the rectangular frame is fixed by a connecting plate, thus forming a rectangular frame with one open end. Correspondingly, two through-beam laser rangefinders are symmetrically arranged on both sides of the open end of the mounting base frame 4, and the space between the two long profiles in the rectangular frame forms a channel for the object to be tested and the calibration plate 101 to enter and exit between the two through-beam laser rangefinders.

[0037] Among them, the calibration mechanism for the detection device based on the dual-line laser rangefinder is referenced. Figure 2 , Figure 3 As shown, the calibration mechanism includes a calibration plate 101 and a fine-tuning mechanism. The calibration plate 101 is located between two through-beam line laser rangefinders. The two vertical planes of the calibration plate 101 facing the two line laser rangefinders are calibration surfaces 1012. The calibration plate 101 has at least one slit 1011 that passes through the two calibration surfaces 1012 and allows the line laser to pass through. The fine-tuning mechanism is used to adjust the installation angle of the two line laser rangefinders so that the laser lines emitted by the two line laser rangefinders pass through the same slit 101.

[0038] It should be understood that due to various physical factors such as installation and manufacturing errors, directly mounting two through-beam line laser rangefinders onto the mounting base 4 cannot completely guarantee that the line lasers emitted by the two through-beam line laser rangefinders are parallel and at the same horizontal height. The slit 1011 is opened at the specific position of the calibration plate 101 according to the approximate height of the line laser emitted by the line laser rangefinder. At this time, the laser line emitted by the line laser rangefinder roughly points to the slit 1011 in the calibration plate 101. The fine-tuning mechanism is used to adjust the mounting angle of the two line laser rangefinders, so that the laser lines emitted by the two line laser rangefinders pass through the same slit 1011.

[0039] refer to Figure 4 As shown, preferably, the width of the slit 1011 is greater than the diameter of the laser beam emitted by the line laser rangefinder. In this embodiment, the diameter of the laser beam emitted by the line laser rangefinder is 50 μm. When the laser propagates in the air, light scattering occurs, which may cause the laser beam observed by the human eye to become diffused. Furthermore, in actual use, small obstructions may occur within the slit, resulting in weak light projection. Therefore, setting a slit with a width slightly larger than the diameter of the laser beam allows for better observation by the human eye, and the micrometer error is almost negligible. To ensure good alignment and ease of observation, the width of the slit 1011 cannot be too large.

[0040] To simplify the adjustment process, refer to Figure 2 As shown, the calibration plate 101 has multiple parallel, spaced-apart slits 1011 with progressively increasing widths. In this embodiment, preferably, there are three slits 1011. Observe the light emitted by the line laser rangefinders as being closer to a certain slit 1011, and select that slit 1011 as the overlapping slit for aligning the laser lines on both sides; then adjust the laser lines emitted by the two line laser rangefinders to pass through the slit 1011.

[0041] Furthermore, the length of the slit 1011 is greater than the projection width of the laser line emitted by the line laser rangefinder on the calibration plate 101.

[0042] As a preferred embodiment of the calibration plate 101, refer to Figure 4 As shown, the calibration plate 101 is mounted on the mounting frame 4. Specifically, the third adapter plate 104 is mounted on the mounting frame 4 and is located at the same end of the mounting frame 4 as the line laser rangefinder. The third adapter plate 104 has a calibration plate connection hole 1041 in the middle, and the calibration plate 101 has a corresponding connection hole. The calibration plate 101 and the third adapter plate 104 are fixedly connected by screws.

[0043] To further improve the stability of the connection between the calibration plate 101 and the third adapter plate 104, a groove is provided on the upper part of the calibration plate 101, and the two sides of the third adapter plate 104 are inserted into the groove of the calibration plate 101.

[0044] In a preferred embodiment of the fine-tuning mechanism, the two fine-tuning mechanisms are a first fine-tuning structure and a second fine-tuning mechanism. The first fine-tuning structure includes a first adapter plate 103 and a first adjustment plate 102, with the first adapter plate 103 fixedly connected to the mounting base frame 4. The first linear laser rangefinder 2 is mounted on the first adapter plate 103 via the first adjustment plate 102. Specifically, the first adjustment plate 102 is mounted on one side of the first linear laser rangefinder 2, and the first adjustment plate 102 and the first adapter plate 103 are connected by a connecting screw 1031. An adjusting screw 1032 is threadedly connected to the first adapter plate 103 and presses against the first adjustment plate 102 to adjust the mounting angle of the first adjustment plate 102.

[0045] After determining a slit 1011 through which the two through-beam linear laser rangefinders pass, the adjustment process is as follows: the connecting screw 1031 is threadedly connected to the first adapter plate 103 and the first adjusting plate 102 and not fully locked; the adjusting screw 1032 is threadedly connected to the first adapter plate 103 and tightened against the first adjusting plate 102; by adjusting the height of the adjusting screw 1032 in the first adapter plate, the distance between different points on the adjacent surfaces of the first adjusting plate 102 and the first adapter plate 103 is adjusted to adjust the tilt angle between the adjacent surfaces, thereby realizing the adjustment of the installation tilt angle of the first adjusting plate 102, that is, the adjustment of the installation angle of the first linear laser rangefinder 2.

[0046] More preferably, the number of adjusting top screws 1032 is four, and the four adjusting top screws 1032 are distributed along the annular interval on the first adapter plate 103 to adjust the tilt angle between the adjacent surfaces of the first adjusting plate 102 and the first adapter plate 103, and can better adjust the tilt angle between the adjacent surfaces of the first adjusting plate 102 and the first adapter plate 103.

[0047] More preferably, the number of connecting screws 1031 is four, the connecting screws 1031 are distributed along the annular interval of the first adapter plate 103, and the adjusting screw 1032 is disposed between two connecting screws 1031.

[0048] In other embodiments, reference is made to... Figure 3 As shown, the second fine-tuning mechanism is used to adjust the installation angle of the second line laser rangefinder 3. The second fine-tuning mechanism is roughly the same as the first fine-tuning mechanism, and the second and first fine-tuning mechanisms are respectively located at the diagonal of the rectangle formed by the first line laser rangefinder 2 and the second line laser rangefinder 3. Specifically, the second fine-tuning mechanism includes a second adjustment plate 105 and a second adapter plate 106. The second adjustment plate 105 is installed on the other side of the second line laser rangefinder 3; the second adapter plate 106 is installed on the mounting base frame 4, and the second adjustment plate 105 and the second adapter plate 106 are threadedly connected and their relative tilt angle can be adjusted.

[0049] Adjusting the height of the adjusting screw 1032 in the first adapter plate 103 according to the dynamic changes of the laser line emitted by the first line laser rangefinder 2, the adjustment of the second line laser rangefinder 3 is the same as that of the first line laser rangefinder. By adjusting the installation angle of the first line laser rangefinder 2 and the second line laser rangefinder 3, the lasers emitted by the two line laser rangefinders move and rotate slightly. When the two through-beam line laser rangefinders pass through the same slit 1011, the connecting screw 1031 locks the relative position of the first adjusting plate 102 and the first adapter plate 103, and the relative position of the second adjusting plate 105 and the second adapter plate 106 is fixed.

[0050] After calibration, remove the calibration plate 101 and the third adapter plate 104. The moving mechanism drives the mounting frame 4 to move, or the object to be tested to move relative to the mounting frame 4, to complete the dimensional detection of the object to be tested. Preferably, the mounting frame 4 is mounted at the output end of the moving mechanism, and the moving mechanism drives the mounting frame 4 to move.

[0051] The detection device based on the dual-line laser rangefinder can place two line laser rangefinders in the same coordinate system using its calibration mechanism, thereby achieving accurate measurement of the object to be measured.

[0052] After replacing the line laser rangefinder or changing the installation position of the line laser rangefinder relative to the mounting base 4, recalibration is required using calibration block 101.

[0053] The present invention and its embodiments have been described above illustratively. This description is not restrictive, and the figures shown are only one embodiment of the present invention; the actual structure is not limited thereto. Therefore, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the inventive spirit of the present invention, such designs should fall within the protection scope of the present invention.

Claims

1. A calibration mechanism for a detection device based on a dual-line laser rangefinder, characterized in that, include: A calibration plate (101) is located between two through-beam line laser rangefinders and has at least one slit (1011) through which the line laser can pass; and A fine-tuning mechanism is provided for adjusting the mounting angle of the two line laser rangefinders so that the light emitted by the two line laser rangefinders passes through the same slit (1011).

2. The calibration mechanism for the detection device based on a dual-line laser rangefinder according to claim 1, characterized in that, The width of the slit (1011) is greater than the diameter of the laser spot emitted by the line laser rangefinder; and / or the calibration plate (101) is provided with multiple parallel slits (1011) with progressively increasing widths.

3. The calibration mechanism for the detection device based on a dual-line laser rangefinder according to claim 1, characterized in that, The length of the slit (1011) is greater than the projection width of the laser line emitted by the line laser rangefinder on the calibration plate (101).

4. The calibration mechanism for the detection device based on a dual-line laser rangefinder according to claim 1, characterized in that, Two through-beam line laser rangefinders are symmetrically arranged on both sides of the same end of the mounting base (4), and a corresponding channel is provided on the mounting base (4) between the two line laser rangefinders.

5. The calibration mechanism for the detection device based on a dual-line laser rangefinder according to any one of claims 1-4, characterized in that, The fine-tuning mechanism includes a first adapter plate (103) and a first adjustment plate (102). The first adapter plate (103) is fixedly connected to the mounting base frame (4). The line laser rangefinder is mounted on the first adapter plate (103) through the first adjustment plate (102). The first adapter plate (103) is threaded with an adjustment screw (1032) for tightening the first adjustment plate (102) to adjust the installation angle of the first adjustment plate (102).

6. The calibration mechanism for the detection device based on a dual-line laser rangefinder according to claim 5, characterized in that, The number of adjusting top screws (1032) is four, and the four adjusting top screws (1032) are distributed along the annular interval on the first adapter plate (103) to adjust the tilt angle between the adjacent surfaces of the first adjusting plate (102) and the first adapter plate (103).

7. The calibration mechanism for the detection device based on a dual-line laser rangefinder according to claim 6, characterized in that, The number of fine-tuning mechanisms is two, and the two fine-tuning mechanisms are respectively set on the diagonal of the rectangle formed by the first line laser rangefinder (5) and the second line laser rangefinder (6).

8. A detection device based on a dual-line laser rangefinder, characterized in that, It includes two through-beam line laser rangefinders and a calibration mechanism as described in any one of claims 1-7, wherein the two through-beam line laser rangefinders and the calibration mechanism (1) are all mounted on the mounting base frame (4).

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