Automatic detection device for surface smoothness

Abstract

The invention discloses an automatic surface smoothness detection device, which relates to the technical field of surface smoothness detection, and comprises an optical platform, the upper end face of which is provided with a strip-shaped positioning through hole; the wedge interference mechanism comprises a standard plane slide I and a workpiece clamping and positioning mechanism; the first standard plane slide is perpendicular to the upper end face of the optical platform. A clamping part of the workpiece clamping and positioning mechanism can clamp and move a to-be-detected workpiece, so that the to-be-detected workpiece horizontally corresponds to the standard plane slide I, an air wedge I with a preset included angle I is formed, and the to-be-detected workpiece can be driven to descend to penetrate through the strip-shaped positioning through hole; the CCD scanning mechanism comprises a light source part and a CCD scanning detection part; the light source part is mounted on the CCD scanning detection part; the sorting mechanism is located below the optical platform and corresponds to the strip-shaped positioning through holes so as to bear the workpieces to be detected and carry out classified conveying. The method can rapidly and accurately carry out automatic nondestructive detection on the surface smoothness of the workpiece to be detected, has relatively high detection efficiency and stability, and can meet the batch detection requirement.

Description

Technical Field

[0001] The present invention relates to the technical field of surface finish detection, in particular to an automatic surface finish detection device. Background Art

[0002] With the development of precision machining technology, people have put forward higher and higher requirements on the surface roughness and surface accuracy of optical components. The quality of the surface of optical components will directly affect the performance of the entire optical system. Therefore, the surface detection technology of optical components has received widespread attention.

[0003] A Chinese patent (publication number CN110618138A, publication date 2019.12.27) discloses a system and method for detecting defects in a display screen using the principle of equal thickness interference. Specifically, the system includes a scanning system, an interference system and an optical microscope module. The interference system includes a glass slide to be tested and a flat glass slide placed at the bottom of the glass slide to be tested. A clamp is set between the glass slide to be tested and the flat glass slide to form an air wedge. The method for detecting defects in a display screen includes the following steps: Step 1: Place the flat glass slide on a measuring platform, set a clamp of a certain thickness between the flat glass slide and the glass slide to be tested to form an air wedge, and form an interference system between the flat glass slide, the glass slide to be tested and the clamp. The system is equipped with a scanning system. Step 2: Adjust the positions of the light source and camera by adjusting the scanning bracket in the scanning system, so that the emitted light from the light source scans the test slide in the direction of increasing air wedge thickness and generates interference fringes. Step 3: During the scanning process, if the interference fringes at the defective part of the test slide are abnormal, the optical microscope module is used to calculate the horizontal distance x from the defect corresponding to the abnormal fringes to the edge of the test slide. The optical microscope module is connected to the camera in the scanning system. Step 4: Remove the clamp and place it on the adjacent side of the test slide to form another air wedge. Repeat steps 2 and 3 to obtain the vertical distance y from the defect corresponding to the abnormal fringes to the edge of the test slide. This technical solution still has the following problems:

[0004] First, the flat glass slide and the glass slide to be tested are placed horizontally, and the surface is easily contaminated by dust;

[0005] Second, the flat glass slide and the glass slide to be tested are placed in contact and stacked, and an air wedge is formed between the two by a clamping block. The operation process requires professional personnel to complete and has many steps and low efficiency, which cannot meet the needs of batch testing; and improper placement of the flat glass slide, the glass slide to be tested and the clamping block can easily cause damage to the flat glass slide and the workpiece to be tested; when the edge of the workpiece to be tested is irregular, especially when there are defects on the edge of the workpiece to be tested, a stable air wedge structure cannot be formed, resulting in increased measurement errors and affecting the test results.

[0006] Third, its technical solution failed to automate the detection and sorting process and was inefficient.

[0007] Therefore, how to design a surface finish automatic detection device based on the principle of wedge-tip interferometry and combined with automation technology, which can quickly and accurately perform automated non-destructive testing of the surface finish of the workpiece to be tested as required, with a measurement accuracy of at least the order of the wavelength of the incident laser, and with high detection efficiency and stability, and can meet the needs of batch testing is an urgent problem that technical personnel in this field need to solve. Summary of the Invention

[0008] In view of this, the present invention proposes an automated surface finish detection device, aiming to solve the technical problems of traditional surface finish detection devices, such as the interference system being easily contaminated by dust, the complicated operation process, the large manual workload and the low detection efficiency.

[0009] In order to achieve the above object, the present invention adopts the following technical solutions:

[0010] In one aspect, the present invention provides an automated surface finish detection device, comprising:

[0011] An optical platform is arranged horizontally, and a strip-shaped positioning through hole is provided on its upper end surface;

[0012] A wedge interference mechanism; the wedge interference mechanism includes a standard plane glass slide and a workpiece clamping and positioning mechanism for placing and clamping a workpiece to be measured; the standard plane glass slide is arranged perpendicular to the upper end surface of the optical platform and corresponds to one side in the width direction of the strip-shaped positioning through-hole; the clamping portion of the workpiece clamping and positioning mechanism can clamp the workpiece to be measured to control the workpiece to be measured to be positioned perpendicular to the upper end surface of the optical platform and corresponding to the strip-shaped positioning through-hole, so that the workpiece to be measured is horizontally aligned with the standard plane glass slide and forms an air wedge with a preset angle, and can drive the workpiece to be measured to descend through the strip-shaped positioning through-hole;

[0013] A CCD scanning mechanism, comprising a light source for irradiating the air wedge to form an interference fringe image and a CCD scanning and detection unit capable of scanning the interference fringe image in a direction parallel to the length of the strip-shaped positioning through-hole to perform a surface finish inspection; the light source is mounted on the CCD scanning and detection unit so as to move synchronously therewith;

[0014] A sorting mechanism; the sorting mechanism is located below the optical platform and corresponds to the strip-shaped positioning through hole to receive the workpiece to be tested transported by the workpiece clamping and positioning mechanism; the sorting mechanism is electrically connected to the CCD scanning and detection part to classify and transport the workpiece to be tested that has completed the inspection according to the inspection results.

[0015] The standard plane glass slide of the automatic surface finish detection device of the present invention is placed vertically, and the surface is not easily contaminated by dust particles, and is easier to keep clean, thereby avoiding the adverse effects of dust particles on the detection results; the workpiece to be measured can be clamped by the workpiece clamping and positioning mechanism for movement and positioning, thereby avoiding surface contamination caused by human hands touching the workpiece to be measured, and there is no contact between the workpiece to be measured and the standard plane glass slide, thereby avoiding bumps and scratches on the surface, and the positioning accuracy of the workpiece to be measured and the standard plane glass slide is also higher and more stable; the workpiece to be measured can be roughly positioned according to the position of the strip-shaped positioning through hole on the optical platform; according to the interference fringe image, the spatial posture of the workpiece to be measured can be fine-tuned by using the workpiece clamping and positioning mechanism to adjust the fringe spacing to make the interference fringe image clearer and reduce measurement errors. The CCD scanning detection part of the CCD scanning mechanism can scan the fringe image formed by the interference of the air wedge along the length direction of the parallel strip positioning through-hole. When the scanning field of view of the CCD scanning detection part cannot cover the entire surface of the workpiece to be tested, the workpiece to be tested can be driven by the workpiece clamping and positioning mechanism to complete the detection of the entire surface to be tested in a step-by-step descending manner, that is, each time the CCD scanning detection part moves horizontally to scan once, the workpiece to be tested descends a certain distance, and the CCD scanning detection part scans the surface of the workpiece to be tested that was not scanned last time, until the CCD scanning detection part scans the entire surface to be tested. The workpiece clamping and positioning mechanism can drive the workpiece to be tested to descend in sections to enter the strip positioning through-hole, and after the detection is completed, the workpiece to be tested passes through the strip positioning through-hole and is placed on the sorting mechanism; the sorting mechanism can classify and transport according to whether the test result is a qualified product. The present invention realizes the rapid and accurate automatic non-destructive testing of the surface finish of the workpiece to be tested as required, has high detection efficiency and stability, and can meet the needs of batch detection.

[0016] As a further improvement of the above technical solution, the CCD scanning mechanism includes a slide rail installed on the optical platform and arranged along the length direction of the strip positioning through hole and an electric translation stage slidably connected to the slide rail; the CCD scanning detection part horizontally corresponds to the standard plane glass slide and is installed on the electric translation stage to translate and scan along the length direction of the slide rail; the light source part is located on the peripheral side of the CCD scanning detection part and is fixed on the electric translation stage through a connecting rod.

[0017] The beneficial effect of the above technical solution is that the electric translation stage can control the CCD scanning detection part to move horizontally at a constant speed to scan the standard plane glass slide 1, so as to realize the collection of the interference fringe image formed by the air wedge interference between the standard plane glass slide 1 and the workpiece to be measured.

[0018] As a further improvement of the above technical solution, the wedge interference mechanism also includes a standard plane glass slide 2, and the standard plane glass slide 2 is arranged on both sides of the width direction of the strip-shaped positioning through hole in a one-to-one correspondence with the standard plane glass slide to define a detection area between the two; when the workpiece to be measured passes through the detection area, an air wedge with a preset angle 2 is formed between it and the standard plane glass slide 2.

[0019] The beneficial effect of the above technical solution is that the standard plane glass slide 1 and the standard plane glass slide 2 are used to form air wedges on both sides of the surface of the corresponding workpiece to be measured, namely air wedge 1 and air wedge 2, which can facilitate one-time positioning to realize the detection of two surfaces.

[0020] As a further improvement of the above technical solution, the plate surfaces of the second standard plane glass slide and the first standard plane glass slide both have the same angle θ with the length direction of the strip-shaped positioning through hole.

[0021] The beneficial effect of the above technical solution is that the included angles θ between the standard plane glass slide 1 and the standard plane glass slide 2 and the length direction of the strip positioning through hole are the same, which can facilitate the construction of air wedges with the same angle on both sides of the workpiece to be measured.

[0022] As a further improvement of the above technical solution, the CCD scanning mechanism is divided into two groups, and the two groups of CCD scanning mechanisms are arranged one by one corresponding to the standard plane glass slide 1 and the standard plane glass slide 2, and are both located on the outside of the relative direction of the standard plane glass slide 1 and the standard plane glass slide 2 to scan and detect the smoothness of the two surfaces of the workpiece to be measured.

[0023] The beneficial effect of the above technical solution is that after the workpiece to be measured is placed in place, the two sets of CCD scanning mechanisms can complete the detection of the two surfaces of the workpiece to be measured, reducing the detection process and improving the detection efficiency.

[0024] As a further improvement of the above technical solution, the wedge-tip interferometer mechanism also includes a standard glass slide driving mechanism installed on the optical platform, and the driving end of the standard glass slide driving mechanism is connected to the standard plane glass slide 1 and the standard plane glass slide 2 to drive the standard plane glass slide 1 and the standard plane glass slide 2 to move along the width direction of the strip-shaped positioning through hole to adjust the horizontal distance between the standard plane glass slide 1, the standard plane glass slide 2 and the workpiece to be measured.

[0025] The beneficial effect of the above technical solution is that the standard glass slide driving mechanism is used to adjust the horizontal distance between the standard plane glass slide 1 and the standard plane glass slide 2 and the workpiece to be measured, which can assist in adjusting the clarity of the wedge-tip interference fringe image.

[0026] As a further improvement of the above technical solution, the workpiece clamping and positioning mechanism includes a rotating lifting positioning mechanism that can move horizontally along the length direction of the strip-shaped positioning through hole and is installed above the optical platform, and a workpiece clamp to be measured arranged above the corresponding strip-shaped positioning through hole; the workpiece clamp to be measured has a fixed end fixed at the driving end of the rotating lifting positioning mechanism and a clamping part that positions and clamps the workpiece to be measured; the rotating lifting positioning mechanism can drive the workpiece clamp to be measured to rotate and lift, so as to insert the workpiece to be measured downward into the detection area in a direction perpendicular to the upper end surface of the optical platform to form air wedge tip 1 and air wedge tip 2, and can rotate to fine-tune the spatial posture of the workpiece to be measured, thereby adjusting the angle size of the preset angle 1 and the preset angle 2.

[0027] The beneficial effects of the above technical solution are: the workpiece holder to be measured is used to vertically clamp and position the workpiece to be measured; the rotary lifting and positioning mechanism can drive the workpiece holder to be measured to rise and fall and move laterally, so that the workpiece to be measured is initially positioned above the corresponding bar-shaped positioning through hole; the rotary lifting and positioning mechanism can drive the workpiece holder to be measured to rotate, and then drive the workpiece to be measured to rotate and fine-tune the spatial posture, so as to adjust the preset angle 1 and the preset angle 2 to be equal.

[0028] As a further improvement of the above technical solution, the strip-shaped positioning through hole is rectangular, and one side wall of the strip-shaped positioning through hole in the width direction is the positioning wall for positioning the workpiece to be measured; the upper end surface of the optical platform corresponding to the side in the width direction of the strip-shaped positioning through hole is provided with a positioning line for locating the position of one end face of the workpiece to be measured.

[0029] The beneficial effects of the above technical solution are: when positioning the workpiece to be measured, the workpiece to be measured can be aligned with the strip-shaped positioning through-hole for rough positioning; the positioning wall surface can be used to quickly position the workpiece to be measured so that its length direction is consistent with the length direction of the strip-shaped positioning through-hole; the positioning scale line is used to position one end face of the workpiece to be measured, and can be quickly adjusted so that the workpiece to be measured is aligned with one end of the standard plane glass slide 1 and the standard plane glass slide 2; the positioning scale line is also the reference for calibrating the starting point of the lateral movement of the CCD scanning detection part.

[0030] As a further improvement of the above technical solution, it further includes a control system, wherein the control system is electrically connected to the workpiece clamping and positioning mechanism to control the workpiece clamping and positioning mechanism to clamp, move, and position the workpiece to be measured;

[0031] The control system is electrically connected to the light source unit and controls the light emitting state of the light source unit;

[0032] The control system is electrically connected to the CCD scanning detection unit to control the CCD scanning detection unit to move and scan at a constant speed and process the scanned image information to obtain a detection result;

[0033] The control system is electrically connected to the sorting mechanism to drive and control the sorting mechanism to classify the workpieces to be tested according to the detection results.

[0034] Another aspect of the present invention provides a surface finish automated detection method, comprising the surface finish automated detection device; the detection steps are:

[0035] Step 1: Place the workpiece to be tested in the inspection area: Use the workpiece clamping and positioning mechanism to clamp and move the workpiece to the top of the bar-shaped positioning through-hole and position it vertically on the upper end surface of the optical platform, so that the workpiece to be tested is horizontally aligned with the standard flat glass slide 1, and an air wedge 1 is formed between the opposing surfaces of the workpiece to be tested and the standard flat glass slide 1;

[0036] Step 2: Detect the surface finish of one side of the workpiece to be measured: Start the CCD scanning mechanism, so that the light source part emits light to illuminate the air wedge to form an interference fringe image; move the CCD scanning detection part along the length direction parallel to the strip-shaped positioning through-hole to scan the interference fringe image to perform surface finish detection; when the scanning field of view of the CCD scanning detection part completely covers the height of the workpiece to be measured in the height direction, a single horizontal scan can complete the surface finish detection of one side of the workpiece to be measured;

[0037] Step 3: When the scanning field height of the CCD scanning detection unit is smaller than the height of the workpiece to be measured and the scanning detection of one side of the workpiece to be measured cannot be completed by a single lateral scan, the workpiece to be measured can be controlled by the workpiece clamping and positioning mechanism to lower the workpiece to be measured along the upper end surface of the vertical optical platform by a preset distance, and the CCD scanning detection unit is started again to perform lateral scanning until the entire surface of one side of the workpiece to be measured is scanned and detected;

[0038] Step 4: Sorting based on the test results: The workpiece to be tested is clamped and moved downward by the workpiece clamping and positioning mechanism and passes through the bar-shaped positioning through-hole to place the workpiece to be tested on the sorting mechanism; the sorting mechanism classifies the tested workpieces according to whether the test results are qualified and transports them to different tested workpiece areas.

[0039] It can be seen from the above technical solutions that, compared with the prior art, the present invention discloses an automated surface finish detection device, which has the following advantages and beneficial effects:

[0040] 1. The present invention can realize automatic detection. Both surfaces of the workpiece to be tested can be tested after one placement and positioning, which improves the detection efficiency. The workpiece to be tested can be classified and sorted according to the detection results, and is suitable for batch detection.

[0041] 2. The CCD scanning mechanism of the present invention only performs lateral scanning motion, and has high motion and detection accuracy. By cooperating with the workpiece clamping and positioning mechanism to vertically move the workpiece to be measured, the entire surface of the workpiece to be measured of different widths can be scanned. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0043] Figure 1 A schematic top view of the overall structure of the automated surface finish detection device of the present invention;

[0044] Figure 2 Schematic diagram of the surface finish automatic detection device of the present invention using a workpiece holder to clamp the workpiece to be tested and suspend it vertically;

[0045] Figure 3 A schematic structural diagram of a workpiece clamping and positioning mechanism of an automated surface finish detection device according to the present invention;

[0046] Figure 4 Schematic diagram of the surface to be tested of the workpiece to be tested and the CCD field of view of the corresponding CCD scanning detection part of the surface finish automatic detection device of the present invention;

[0047] Figure 5 Schematic diagram of the wedge-tip interferometry principle of the surface finish automatic detection device of the present invention;

[0048] Figure 6 Schematic diagram of the analysis principle of the surface unevenness (presence of depressions) of the workpiece to be tested by the automatic surface finish detection device of the present invention;

[0049] Figure 7 Schematic diagram of the analysis principle of the surface unevenness (protrusions) of the workpiece to be tested by the automatic surface finish detection device of the present invention;

[0050] Figure: 1, optical platform; 11, strip positioning hole; 111, positioning wall; 12, positioning scale line; 13, scale line; 2, wedge tip interferometer; 21, standard plane glass slide 1; 22, workpiece to be measured; 23, workpiece clamping and positioning mechanism; 231, rotary lifting and positioning mechanism; 2311, rotary motor; 2312, lifting rod; 232, workpiece clamp to be measured; 2321, crossbeam; 2322, fixed clamping jaw; 2323, movable Gripper; 233, guide rail; 24, air wedge 1; 25, standard flat glass slide 2; 26, air wedge 2; 27, standard glass slide drive mechanism; 3, CCD scanning mechanism; 31, light source unit; 311, laser; 312, beam expander; 313, semi-transparent, semi-reflective mirror; 32, CCD scanning detection unit; 33, slide rail; 34, electric translation stage; 35, connecting rod; 4, sorting mechanism; 41, sorting drive conveyor belt; 5, control system. DETAILED DESCRIPTION

[0051] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

[0052] In the description of the present invention, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0053] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0054] In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0055] like Figures 1 to 7 As shown, the surface finish automatic detection device includes:

[0056] The optical platform 1 is arranged horizontally, and a strip-shaped positioning through hole 11 is provided on its upper end surface;

[0057] Wedge interferometer mechanism 2; the wedge interferometer mechanism 2 includes a standard plane glass slide 1 21, a workpiece 22 to be measured, and a workpiece clamping and positioning mechanism 23 for placing and clamping the workpiece 22 to be measured; the standard plane glass slide 1 21 is arranged perpendicular to the upper end surface of the optical platform 1 and corresponds to one side in the width direction of the strip-shaped positioning through hole 11; the clamping portion of the workpiece clamping and positioning mechanism 23 can clamp the workpiece 22 to be measured, so as to control the workpiece 22 to be measured to be positioned perpendicular to the upper end surface of the optical platform 1 and corresponding to the strip-shaped positioning through hole 11, so that the workpiece 22 to be measured is horizontally aligned with the standard plane glass slide 1 21 and forms an air wedge 24 with a preset angle 1, and can drive the workpiece 22 to be measured to descend through the strip-shaped positioning through hole 11;

[0058] The CCD scanning mechanism 3 includes a light source portion 31 for irradiating the air wedge tip 24 to form an interference fringe image, and a CCD scanning detection portion 32 for scanning the interference fringe image along the length direction of the parallel strip-shaped positioning through hole 11 to perform surface finish detection. The light source portion 31 is mounted on the CCD scanning detection portion 32 to move synchronously with the CCD scanning detection portion 32.

[0059] Sorting mechanism 4; the sorting mechanism 4 is located below the optical platform 1 and corresponds to the bar-shaped positioning through hole 11 to receive the workpiece 22 to be tested transported by the workpiece clamping and positioning mechanism 23; the sorting mechanism 4 is electrically connected to the CCD scanning detection unit 32 to classify and transport the workpiece 22 to be tested after the test is completed according to the test results.

[0060] The standard plane glass slide 21 of the surface finish standard plane glass slide 21 automated detection device of this embodiment is placed vertically, and its surface is not easily contaminated by dust particles, making it easier to keep clean, thereby avoiding the adverse effects of dust particles on the detection results. The workpiece clamping and positioning mechanism 23 can clamp the workpiece 22 to be tested for movement and positioning, thereby avoiding surface contamination caused by human hands touching the workpiece 22 to be tested. There is no contact between the workpiece 22 to be tested and the standard plane glass slide 21, thereby avoiding bumps and scratches on the surface. The positioning accuracy of the workpiece 22 to be tested and the standard plane glass slide 21 is also higher and more stable. The workpiece 22 to be tested can be roughly positioned based on the position of the strip-shaped positioning through hole 11 on the optical platform 1. According to the interference fringe image, the workpiece clamping and positioning mechanism 23 can be used to fine-tune the spatial posture of the workpiece 22 to be tested, so as to adjust the fringe spacing to make the interference fringe image clearer and reduce measurement errors. The CCD scanning detection unit 32 of the CCD scanning mechanism 3 can scan the fringe image formed by the interference of the air wedge tip 24 along the length direction of the parallel strip positioning through hole 11. When the scanning field of view of the CCD scanning detection unit 32 cannot cover the entire surface of the workpiece 22 to be tested, the workpiece clamping and positioning mechanism 23 can drive the workpiece 22 to be tested to descend in sections to complete the detection of the entire surface to be tested. That is, each time the CCD scanning detection unit 32 moves horizontally to scan, the workpiece 22 to be tested descends a certain distance, and the CCD scanning detection unit 32 scans the surface of the workpiece 22 to be tested that was not scanned last time until the CCD scanning detection unit 32 scans the entire surface to be tested. The workpiece clamping and positioning mechanism 23 can drive the workpiece 22 to be tested to descend in sections to enter the strip positioning through hole 11, and after the detection is completed, the workpiece 22 to be tested passes through the strip positioning through hole 11 and is placed on the sorting mechanism 4; the sorting mechanism 4 can classify and transport the workpiece 22 according to whether the test result is qualified. The present invention realizes the rapid and accurate automatic non-destructive testing of the surface finish of the workpiece to be tested as required, has high testing efficiency and stability, and can meet the needs of batch testing.

[0061] Specifically, the light source unit 31 includes a laser 311, a beam expander 312 and a semi-transparent and semi-reflective mirror 313; the laser emitted by the laser 311 is used as the light source, and the beam expander is used to expand the beam, thereby increasing the superposition area of ​​the two waves, making it easier to simultaneously detect more areas on the surface of the workpiece to be measured.

[0062] Figure 1 The laser light is represented by a solid line with an arrow, showing the laser light path, and the incident light is incident on the semi-transparent and semi-reflective mirror 313 at an incident angle of 45° along the positive direction of the X-axis; the semi-transparent and semi-reflective mirror 313 is located between the CCD scanning and detection part 32 and the strip-shaped positioning through hole 11; the mirror surface of the semi-transparent and semi-reflective mirror 313 is perpendicular to the upper end surface of the optical platform 1; the mirror surface of the semi-transparent and semi-reflective mirror 313 is at an angle of 45° to the length direction of the strip-shaped positioning through hole 11, and is fixed on the CCD scanning and detection part 32.

[0063] In some embodiments, the CCD scanning mechanism 3 includes a slide rail 33 installed on the optical platform 1 and arranged along the length direction of the strip positioning through hole 11, and an electric translation stage 34 slidably connected to the slide rail 33; the CCD scanning detection part 32 horizontally corresponds to the standard plane glass slide 21 and is installed on the electric translation stage 34 to translate and scan along the length direction of the slide rail 33; the light source part 31 is located on the side of the CCD scanning detection part 32 and is fixed to the electric translation stage 34 through a connecting rod 35.

[0064] The electric translation stage 34 can control the CCD scanning detection unit 32 to move horizontally and uniformly scan the standard plane glass slide 21 at a constant speed, so as to collect the interference fringe image formed by the air wedge interference between the standard plane glass slide 21 and the workpiece 22 to be measured.

[0065] In some embodiments, the wedge interference mechanism 2 also includes a standard plane glass slide 25, and the standard plane glass slide 25 and the standard plane glass slide 1 21 are arranged on both sides of the width direction of the strip positioning hole 11 in a one-to-one manner to define a detection area between the two; when the workpiece 22 to be measured passes through the detection area, an air wedge 26 with a preset angle 2 is formed between it and the standard plane glass slide 25.

[0066] The standard plane glass slide 1 21 and the standard plane glass slide 2 25 are used to form air wedges on both sides of the corresponding workpiece 22, namely, air wedge 1 24 and air wedge 2 26, which can facilitate one-time positioning to realize the detection of two surfaces.

[0067] In some embodiments, the plate surfaces of the second standard plane glass slide 25 and the first standard plane glass slide 21 both have the same angle θ with the length direction of the strip-shaped positioning through hole 11 .

[0068] The included angle θ between the surface of the standard plane glass slide 1 21 and the standard plane glass slide 2 25 and the length direction of the strip positioning through hole 11 is the same (the included angle θ is the wedge angle of the air wedge 1 24 and the air wedge 2 26), which can facilitate the construction of air wedges with the same angle on both sides of the workpiece 22 to be measured.

[0069] In some embodiments, there are two groups of CCD scanning mechanisms 3, and the two groups of CCD scanning mechanisms 3 are arranged one by one corresponding to the standard plane glass slide 1 21 and the standard plane glass slide 2 25, and are both located on the outside of the relative direction of the standard plane glass slide 1 21 and the standard plane glass slide 2 25 to scan and detect the smoothness of the two surfaces of the workpiece 22 to be measured.

[0070] After the workpiece 22 to be measured is placed in place, the two sets of CCD scanning mechanisms 3 can complete the detection of two surfaces of the workpiece 22 to be measured, reducing the detection process and improving the detection efficiency.

[0071] In some embodiments, the wedge interferometer mechanism 2 also includes a standard glass slide driving mechanism 27 mounted on the optical platform 1. The driving end of the standard glass slide driving mechanism 27 is connected to the standard plane glass slide 1 21 and the standard plane glass slide 2 25 to drive the standard plane glass slide 1 21 and the standard plane glass slide 2 25 to move along the width direction of the strip positioning through hole 11 to adjust the horizontal distance between the standard plane glass slide 1 21, the standard plane glass slide 2 25 and the workpiece to be measured 22, thereby adjusting the clarity of the wedge interferometer fringe image.

[0072] The standard glass slide driving mechanism 27 is used to adjust the horizontal distance between the standard plane glass slide 1 21 and the standard plane glass slide 2 25 and the workpiece 22 to be measured, and can assist in adjusting the clarity of the wedge-tip interference fringe image.

[0073] In some embodiments, the strip-shaped positioning hole 11 is rectangular, and one side wall of the strip-shaped positioning hole 11 in the width direction is a positioning wall 111 for positioning the workpiece 22 to be measured; a positioning line 12 for locating the position of one end face of the workpiece 22 to be measured is provided on the side of the upper end face of the optical platform 1 corresponding to the width direction of the strip-shaped positioning hole 11.

[0074] Specifically, a scale line 13 is provided on the upper end surface of the optical platform 1 corresponding to the top of the positioning wall 111 along the length direction of the parallel strip positioning through hole 11; the positioning scale line 12 serves as the zero point of the scale line 13, and the scale line 13 is provided with positive and negative scales on both sides of the positioning scale line 12.

[0075] When positioning the workpiece 22 to be measured, the workpiece 22 to be measured can be aligned with the strip-shaped positioning through-hole 11 for rough positioning; the positioning wall 111 can be used to quickly position the workpiece 22 to be measured so that its length direction is consistent with the length direction of the strip-shaped positioning through-hole 11; the positioning scale line 12 is used to position one end face of the workpiece 22 to be measured, and can be quickly adjusted so that the workpiece 22 to be measured is aligned with one end of the standard plane glass slide 1 21 and the standard plane glass slide 2 25; the positioning scale line 12 is also the reference for calibrating the starting point of the lateral movement of the CCD scanning detection unit 32.

[0076] In some embodiments, the workpiece clamping and positioning mechanism 23 includes a rotating and lifting positioning mechanism 231 that can move laterally along the length direction of the strip-shaped positioning through hole 11 and is installed above the optical platform 1, and a workpiece clamp 232 to be measured arranged above the corresponding strip-shaped positioning through hole 11; the workpiece clamp 232 to be measured has a fixed end fixed to the driving end of the rotating and lifting positioning mechanism 231 and a clamping part for positioning and clamping the workpiece 22 to be measured; the rotating and lifting positioning mechanism 231 can drive the workpiece clamp 232 to be measured to rotate and lift, so as to insert the workpiece 22 to be measured downward into the detection area along the direction perpendicular to the upper end surface of the optical platform 1 to form an air wedge tip 1 24 and an air wedge tip 26, and can rotate to fine-tune the spatial posture of the workpiece 22 to be measured, thereby adjusting the angle size of the preset angle 1 and the preset angle 2.

[0077] The workpiece holder 232 to be measured is used to vertically clamp and position the workpiece 22 to be measured; the rotary lifting and positioning mechanism 231 can drive the workpiece holder 232 to be measured to rise and fall and move laterally so that the workpiece 22 to be measured is initially positioned above the corresponding bar-shaped positioning through hole 11; the rotary lifting and positioning mechanism 231 can drive the workpiece holder 232 to be measured to rotate, and then drive the workpiece 22 to be measured to rotate and fine-tune the spatial posture to adjust the preset angle 1 and the preset angle 2 to be equal.

[0078] Specifically, the workpiece clamping and positioning mechanism 23 also includes a guide rail 233 arranged directly above the strip positioning through hole 11 along the length direction parallel to the strip positioning through hole 11; the guide rail 233 is fixedly connected to the optical platform 1 through a support frame; the rotating and lifting positioning mechanism 231 includes a rotating motor 2311 and a lifting rod 2312; the fixed end of the rotating motor 2311 is slidably connected to the guide rail 233; the rotating shaft of the rotating motor 2311 is fixedly connected to the fixed end of the lifting rod 2312, and the telescopic end of the lifting rod 2312 is fixedly connected to the fixed end of the workpiece holder 232 to be measured. The clamping portion of the workpiece holder 232 includes a crossbeam 2321, a fixed jaw 2322, and a movable jaw 2323. The upper end of the crossbeam 2321 is fixedly connected to the telescopic end of the lifting rod 2312. The upper end of the fixed jaw 2322 is vertically fixed to one side of the lower end of the crossbeam 2321. The upper end of the movable jaw 2323 is vertically and slidably connected to the lower end of the crossbeam 2321. The movable jaw 2323 and the fixed jaw 2322 are arranged opposite each other along the length of the crossbeam 2321. The movable jaw 2323 and the fixed jaw 2322 use opposing inner vertical cutting edges to jointly position and clamp the left and right end surfaces of the workpiece 22 to be measured.

[0079] During use, the workpiece holder 232 is used to clamp the left and right end surfaces of the workpiece 22 and suspend the workpiece 22 vertically on the strip-shaped positioning hole 11 of the optical platform 1. Depending on the actual situation, the workpiece holder 232 is fine-tuned and rotated by controlling the rotary motor 2311, so that the workpiece holder 232 is fine-tuned and rotated about the vertical direction on the upper end surface of the optical platform 1, so that one side of the workpiece 22 is aligned with the positioning wall 111. The workpiece holder 232 is then translated along a guide rail parallel to the length of the strip-shaped positioning hole 11, so that the left end of the workpiece 22 is aligned with the positioning mark 12, i.e., the position x0 in the figure, to achieve precise positioning of the workpiece 22, and the lower surface of the workpiece 22 is at the same height as the upper end surface of the optical platform at the corresponding strip-shaped positioning hole 11.

[0080] The surfaces of the standard plane glass slide 1 21 and the standard plane glass slide 2 25 are both perpendicular to the upper end surface of the optical platform 1; the angle between them and the length direction of the strip positioning through hole 11 is θ (or -θ). Driven by the standard glass slide driving mechanism 27, the standard plane glass slide 1 21 and the standard plane glass slide 2 25 can be translated along the width direction of the strip positioning through hole 11 within a small range between the CCD scanning mechanism 3 and the workpiece to be measured 22; this can not only achieve optimal imaging of the workpiece to be measured by the CCD scanning mechanism 3, but also maintain the angle θ between the workpiece to be measured 22 and the standard plane glass slide 1 21 and the standard plane glass slide 2 25 unchanged, thereby ensuring the precision and accuracy of the measurement.

[0081] Specifically, the standard slide driving mechanism 27 can be a manual drum commonly used in optical platform equipment.

[0082] Before entering the inspection procedure (i.e., inspecting the surface finish of the workpiece to be measured), on the one hand, according to the thickness of the workpiece to be measured 22, the standard part, which has an angle θ with the length direction of the strip positioning through hole 11, needs to be translated along the width direction of the strip positioning through hole 11 to a suitable width to avoid collision and damage between the workpiece to be measured 22 and the left end of the standard plane glass slide 1 21 and the standard plane glass slide 2 25 when the workpiece to be measured is placed in the inspection area, thereby avoiding affecting the measurement accuracy due to the change in the angular positioning of the standard plane glass slide 1 21 and the standard plane glass slide 2 25; on the other hand, after the workpiece to be measured 22 is placed in the inspection area, the distance between the standard plane glass slide 1 21, the standard plane glass slide 2 25 and the workpiece to be measured 22 is adjusted to a suitable width so that the CCD scanning detection unit 32 can collect sharper and clearer interference fringe patterns.

[0083] The wedge interferometry mechanism 2 is the core component for measuring the surface finish of a workpiece. The workpiece 22 is placed in the inspection area, and parallel light is applied perpendicularly to the air wedge (the angle between the standard flat slide 1 21, the standard flat slide 2 25, and the workpiece 22 is θ, with a minimum angle of θ, preferably 6', forming the thin film of air between them). This produces alternating light and dark interference fringes on the upper surface of the air wedge. The interference fringe pattern will vary depending on the surface finish of the workpiece 22. Therefore, by analyzing the interference fringe pattern, information about the surface finish of the workpiece can be obtained.

[0084] In some embodiments, a control system 5 is further included, the control system 5 being electrically connected to the workpiece clamping and positioning mechanism 23 to control the workpiece clamping and positioning mechanism 23 to clamp, move, and position the workpiece 22 to be measured;

[0085] The control system 5 is electrically connected to the light source 31 and controls the light state of the light source 31 on and off;

[0086] The control system 5 is electrically connected to the CCD scanning detection unit 32 to control the CCD scanning detection unit 32 to move and scan at a constant speed and process the scanned image information to obtain a detection result;

[0087] The control system 5 is electrically connected to the sorting mechanism 4 to drive and control the sorting mechanism 4 to sort the workpieces 22 to be tested according to the detection results.

[0088] Of course, after the fine-tuning rotary motor 2311 rotates, the detection system can be activated to check whether the angles between the standard plane glass slide 1 21, the standard plane glass slide 2 25, and the workpiece 22 to be measured are equal. This can be done by observing whether the number of bright (dark) fringes or the fringe spacing in the interference fringe patterns captured by the two CCD scanning detection units 32 are the same. If the number of bright (dark) fringes or the fringe spacing in the interference fringe patterns captured by the two CCD scanning detection units 32 are the same, the next step is performed. If they are different, the rotation of the workpiece holder 232 to be measured is further fine-tuned until the number of bright (dark) fringes or the fringe spacing in the interference fringe patterns captured by the two CCD scanning detection units 32 are the same, thereby ensuring that the angles of the air wedges (air wedge 1 24 and air wedge 26) formed on both sides of the workpiece 22 to be measured are both θ.

[0089] Specifically, in order to facilitate making the angles between the workpiece 22 to be measured inserted into the detection area and the standard plane glass slide 1 21 and the standard plane glass slide 2 25 equal, on the premise that the standard plane glass slide 1 21 and the standard plane glass slide 2 25 both have an angle θ with the length direction of the strip positioning through hole 11, it can be designed to make the plate surfaces of the standard plane glass slide 2 25 and the standard plane glass slide 1 21 parallel. Then, when the workpiece 22 to be measured is vertically inserted into the detection area between the standard plane glass slide 2 25 and the standard plane glass slide 1 21, it can always be ensured that the preset angle 1 is equal to the preset angle 2. Fine-tuning the rotation of the workpiece 22 to be measured can synchronously change the preset angle 1 and the preset angle 2.

[0090] Specifically, the CCD scanning detection unit 32 is fixedly connected to the semi-transparent and semi-reflective mirror through the lens barrel of the CCD scanning detection unit 32. The CCD scanning detection unit 32 and the electric translation stage 34 are both electrically connected to the control system 5. The CCD scanning detection unit 32 can be used to collect interference patterns and transmit them to the control system 5. A displacement sensor (displacement data acquisition system) is provided in the electric translation stage 34 to enable the CCD scanning detection unit 32 to move along the length direction of the slide rail 33, thereby enabling the CCD scanning detection unit 32 to collect interference fringes in different areas of the surface of the workpiece 22 to be measured (such as Figure 4 ).

[0091] Specifically, the CCD scanning detection unit 32 is fixedly connected to the light source unit 31 by an L-shaped connecting rod 35. The distance between the CCD scanning detection unit 32 and the light source unit 31 is fixed, but under the action of the electric translation stage 34, the two can move together along the horizontal slide rail 33 parallel to the length direction of the strip-shaped positioning through hole 11. The synchronous movement of the CCD scanning detection unit 32 and the light source unit 31 can, on the one hand, realize real-time imaging and real-time acquisition, and on the other hand, ensure that the light intensity of each frame of the interference pattern collected by the CCD scanning detection unit 32 is consistent. During the device detection process, if the two sides of the transparent workpiece 22 to be measured are detected at the same time, parallel light from both sides will be simultaneously irradiated onto the workpiece 22 to be measured, and the transmitted light formed will interfere with the interference pattern on the other side. Therefore, the two sides of the transparent workpiece 22 to be measured can be detected step by step. Of course, for the opaque workpiece 22 to be measured, the two sides of the workpiece 22 to be measured can be detected synchronously to further improve the detection efficiency.

[0092] Specifically, the control system 5 includes a drive control and positioning system and a computer software system.

[0093] The driving and positioning system includes: an electric translation stage driver, which is used to drive the overall positioning and translation of the light source part 31 and the CCD scanning detection part 32 of the CCD scanning mechanism 3, thereby realizing the detection of the surface finish of a large-area workpiece 22 to be measured; a workpiece clamping and positioning driver, which is used to drive the workpiece 22 to be measured to the detection area, and correctly place its position according to the size of the workpiece 22 to be measured, and finally drive the workpiece 22 to be measured to the classification drive conveyor belt 41 of the sorting mechanism 4 according to the detection results; a classification driver: used to drive the classification drive conveyor belt 41 of the sorting mechanism 4 to transport, and drive the workpiece 22 to be measured transferred by the workpiece clamping and positioning mechanism 23 to the measured workpiece area as required.

[0094] The computer software system includes a computer, workpiece surface finish analysis software, and automated drive software. During the automated inspection process, these two software programs run simultaneously and call each other's results. For example, the automated drive software will call the inspection results of the workpiece surface finish analysis software and implement classification drive for the inspected workpieces based on the inspection results.

[0095] The automatic detection and driving process of the surface finish automatic detection device is as follows:

[0096] Step 1: Place the workpiece to be tested in the detection area

[0097] The workpiece holder 232 is driven to clamp the workpiece 22 and vertically suspend it above the optical platform strip-shaped positioning through hole 11 (ie, the workpiece 22 is positioned in the detection area).

[0098] Specific requirements: Fine-tune the rotary lifting positioning mechanism 231 according to actual conditions, so that the workpiece holder 232 to be measured slightly rotates the workpiece 22 to be measured along the vertical axis in the horizontal plane, so that one side of the workpiece 22 to be measured is aligned with the scale line 13, and then let the workpiece holder 232 to be measured translate along the length direction of the parallel strip positioning through hole 11, so that the left end of the workpiece 22 to be measured is aligned with the positioning scale line 12, that is, aligned with the scale zero point x0, to achieve precise positioning of the workpiece to be measured, and the lower surface of the workpiece 22 to be measured is at the same height as the horizontal upper end surface of the optical platform.

[0099] Step 2: Detect the surface finish of one side of the workpiece 22 to be tested

[0100] The electric translation stage 34 is driven to align the CCD scanning detection unit 32 horizontally with the wedge ends of the air wedge 1 24 and the air wedge 2 26 , and the movement of the standard plane glass 2 25 and the standard plane glass 1 21 is fine-tuned so that the wedge interference pattern can be clearly observed on the computer.

[0101] Specific requirements: The projection of the center of the CCD square field of view (i.e. the center of the square circumscribed circle) of the CCD scanning detection unit 32 on the scale line 13 coincides with point O (e.g. Figure 4 As shown, at this time, the horizontal displacement reading of the CCD scanning detection unit 32 is zero). Then, the electric translation stage 34 begins to move away from the wedge end along the parallel horizontal slide rail 33, and the interference pattern acquisition system continuously acquires interference fringes at different positions on the surface of the workpiece 22 to be measured (with the length of each frame as an interval), until the horizontal displacement of the interference pattern acquisition system relative to the point O near the wedge end reaches S (as shown in FIG. Figure 4 As shown, at this time, the projection of the center of the CCD square field of view on the scale line 13 coincides with point O'). At this time, the center of the CCD square field of view has reached the designed target position (the size of the S value is determined by the size of the workpiece to be measured, and the position can be changed by changing the S value). The displacement data acquisition system feeds back the horizontal displacement reading S to the automatic drive software, thereby pausing the electric translation stage drive. At the same time, the interference pattern acquisition system stops acquiring after completing the acquisition of the frame, and the automatic drive software drives the electric translation stage 34 back to the original position again (at this time, the surface has not been completely inspected, and the area inspected this time is only (sr + r 2 ),Right now Figure 4 The shaded area in ).

[0102] Step 3: Detect the surface finish of the other side of the workpiece 22 to be tested. The detailed operation process is the same as that of the second step.

[0103] Step 4: According to the actual size of the workpiece 22 to be measured, the lifting rod 2312 is raised and lowered, and the second and third steps are repeated to realize the detection of the surface finish of both sides of the entire workpiece 22 to be measured.

[0104] Step 5: Transfer the inspected workpiece to the inspected workpiece area

[0105] Based on the test results (provided by the computer), the workpieces 22 to be tested are classified and driven into different areas according to their surface finish. If the tested workpiece does not meet the requirements, the automated drive software issues a corresponding instruction to the sorting drive conveyor 41 of the sorting mechanism 4 to drive the tested workpiece out of the device at a uniform speed v1 along the negative direction of the scale line 13. If the tested workpiece meets the requirements, the automated drive software issues another instruction to the sorting drive conveyor 41 of the sorting mechanism 4 to drive the tested workpiece out of the device at a uniform speed v1 along the positive direction of the scale line 13.

[0106] Another embodiment provides a surface finish automated detection method, including a surface finish automated detection device; the detection steps are:

[0107] Step 1: Place the workpiece to be tested in the inspection area: Use the workpiece clamping and positioning mechanism 23 to clamp and move the workpiece to be tested 22 to the top of the strip-shaped positioning through-hole 11 and position it perpendicular to the upper end surface of the optical platform 1, so that the workpiece to be tested 22 is horizontally aligned with the standard flat glass slide 1 21, and an air wedge 1 24 is formed between the opposing surfaces of the workpiece to be tested 22 and the standard flat glass slide 1 21;

[0108] Step 2: Detecting the surface finish of one side of the workpiece to be measured: Start the CCD scanning mechanism 3, so that the light source unit 31 emits light to illuminate the air wedge 24 to form an interference fringe image; move the CCD scanning detection unit 32 along the length direction parallel to the strip-shaped positioning through hole 11 to scan the interference fringe image to perform surface finish detection; when the scanning field of view of the CCD scanning detection unit 32 completely covers the height of the workpiece to be measured 22 in the height direction, a single transverse scan can complete the surface finish detection of one side of the workpiece to be measured;

[0109] Step 3: When the scanning field height of the CCD scanning detection unit 32 is less than the height of the workpiece 22 to be measured and the scanning detection of one side of the workpiece 22 cannot be completed by a single lateral scan, the workpiece 22 to be measured can be controlled by the workpiece clamping and positioning mechanism 23 to descend a preset distance in a direction perpendicular to the upper end surface of the optical platform 1, and the CCD scanning detection unit 32 is started again to perform lateral scanning until the entire surface of one side of the workpiece 22 to be measured is scanned and detected;

[0110] Step 4: Sorting according to the test results: The workpiece clamping and positioning mechanism 23 clamps and moves the workpiece 22 to be tested downward and passes through the bar-shaped positioning through-hole 11 to place the workpiece 22 to be tested on the sorting mechanism 4; the sorting mechanism 4 classifies the workpiece 22 to be tested and transports it to different tested workpiece areas according to whether the test results are qualified.

[0111] Specifically, the device detection process is as follows:

[0112] Step 1: Dimensional requirements of the workpiece to be measured: If the length of the standard parts (i.e., standard flat glass slide 1 21 and standard flat glass slide 2 25) is d (d is greater than or equal to the length of the workpiece to be measured 22), the square field of view of the CCD ( Figure 4 The side length of the square inscribed within the dotted circle is r. This means that during a single translation of the motorized translation stage 34, the CCD scanning and detection unit 32 can capture an interference pattern covering a distance r in the height direction. Therefore, the maximum length (along the length of the scale lines 13) of a vertically suspended workpiece 22 to be tested must be d, and its height (in a direction perpendicular to the upper end face of the optical platform 1) must not exceed the distance between the upper end face of the optical platform 1 and the underlying drive conveyor belt 41. Otherwise, the workpiece cannot be inspected by this device.

[0113] Step 2: Clamp the workpiece to be tested to the testing area: Figure 3 As shown, the workpiece 22 to be measured is placed on the workpiece holder 232, and the fixed jaws 2322 and the movable jaws 2323 cooperate to clamp the workpiece 22 at both ends in the length direction. Then, the lifting rod 2312 (containing a displacement sensor) descends until the lower end of the workpiece 22 to be measured is at the same height as the upper end surface of the optical platform 1. The movement is then paused, and the rotary motor 2311 is fine-tuned to make the workpiece 22 to be measured rotate slightly in the horizontal plane around the axis of the lifting rod 2312, so that one side of the workpiece 22 to be measured is aligned. Figure 1 The middle scale line 13 (marked with scale) is the X-axis position; then the workpiece holder 232 is moved horizontally along the guide rail 233 so that the left end of the workpiece 22 is aligned with the scale x0, and the workpiece 22 is accurately positioned. At this time, the center of the dotted circle coincides with the center of the square field of view (as shown in the figure). Figure 4 As shown, the CCD scanning detection portion 32 corresponds to the wedge end and the horizontal displacement reading is zero).

[0114] Step 3: Detection begins. The specific steps are as follows:

[0115] Step 3.1: Turn on the laser 311 and the CCD scanning detection unit 32 of the CCD scanning mechanism 3, first detect the surface of one side of the workpiece 22 to be measured, and adjust the manual drum wheel to achieve the best imaging of the workpiece 22 by the CCD scanning detection unit 32.

[0116] Step 3.2: Start the displacement data acquisition system and automated driver software on the computer. The motorized translation stage 34 drives the CCD scanning detection unit 32 and light source unit 31 to smoothly move along the horizontal slide rail 33 (parallel to the X-axis) at a constant speed v0 (dependent on the CCD frames per second and the distance each frame moves). The interference pattern acquisition system continuously captures interference fringes at different locations on the surface of the workpiece 22, with each frame duration as the interval. Simultaneously, the interference pattern acquisition system transmits the images to the computer, where the workpiece surface finish analysis software performs real-time surface finish analysis on the workpiece. When the displacement of the electric translation stage 34 along the slide rail 33 reaches S = d'-r (d' is the actual length of the workpiece to be measured along the length direction of the scale line 13), the CCD scanning detection part 32 reaches the target position O', the computer makes a judgment, the automatic driving software pauses the driving of the electric translation stage 34 and stops the interference pattern acquisition system after acquiring the frame, and then the automatic driving software drives the electric translation stage 34 back to its original position, that is, the splitting end.

[0117] Step 3.3: At this time, the CCD scanning mechanism 3 corresponding to the surface of one side of the workpiece 22 to be measured (positive direction of the Y axis) is turned off, and the CCD scanning mechanism 3 corresponding to the surface of the other side of the workpiece 22 to be measured (negative direction of the Y axis) is turned on. Repeat the above steps 3.1 and 3.2 until the electric translation stage 34 corresponding to the surface of the other side of the workpiece 22 to be measured is driven back to its original position, and at the same time, the CCD scanning mechanism 3 corresponding to the surface of the other side of the workpiece 22 to be measured is turned off.

[0118] Step 3.4: After this, under the action of the displacement data acquisition system and the automated driving software, the lifting rod 2312 vertically descends r (r is the side length of the CCD square field of view), and the CCD scanning mechanism 3 corresponding to the surface of one side of the workpiece 22 to be measured is turned on again, but there is no need to adjust the manual drum wheel afterwards.

[0119] Repeat steps 3.1, 3.2, 3.3, and 3.4 until both surfaces of the vertically placed workpiece 22 are completely inspected and transferred to the classification drive conveyor belt 41 under the optical platform for classification drive, and the workpiece holder 232 returns to its initial position before inspection.

[0120] Step 4: Classify the measured workpieces: The workpiece surface finish analysis software in the computer software system analyzes each frame of the workpiece surface interference fringe pattern collected by the interference pattern acquisition system, and extracts the maximum value of the fringe concave part (the fringe appears in advance along the positive direction of the X axis) or the convex part (the fringe appears in the backward direction of the X axis), which is recorded as a max =max{a 凹 ,a 凸Since the selected laser wavelength λ is known, the fringe spacing b is also known, that is, (Δe represents the thickness difference of the cleaved film corresponding to two adjacent bright or dark stripes, for air ). Therefore, the workpiece surface finish analysis software uses the formula Calculate the maximum depth or height h of the texture max , and according to whether the curved stripes appear in advance or in the positive direction of the X axis, the surface of the workpiece is given as concave or convex. The maximum depth or height of this pattern h max Compare with the pre-specified allowable error h0.

[0121] If h max > h0, the measured workpiece does not meet the requirements, the automatic drive software will call the test results of the workpiece surface finish analysis software, and according to the test results h max >h0, it is known that the measured workpiece does not meet the requirements, and the automatic drive software gives the classification drive conveyor 41 a corresponding instruction to drive the measured workpiece out of the device at a uniform speed of υ1 along the negative direction of the X axis.

[0122] If h max ≤h0, the workpiece meets the requirements, and the automatic drive software will also call the test results of the workpiece surface finish analysis software and calculate the test results based on the test results h max ≤h0, it is known that the measured workpiece meets the requirements, and the automation drive software gives another instruction to the classification drive conveyor belt to drive the measured workpiece out of the device at a uniform speed of υ1 along the positive direction of the X axis.

[0123] Specifically, the measurement principle and calculation process are as follows:

[0124] The measurement principle is the wedge interference principle, that is, a flat glass plate (standard part) is placed on the workpiece to be tested (the workpiece to be tested), so that an air wedge is formed between the workpiece to be tested and the standard part. When parallel light is vertically irradiated on the air wedge, an interference fringe pattern of alternating light and dark will be generated on the upper surface of the air wedge. The interference fringe pattern on the surface of the standard part is collected by CCD and transmitted to the computer. According to the wedge interference principle, if the observed interference fringes are parallel straight stripes with equal spacing, it means that the surface of the workpiece is flat; if the observed interference fringes are curved, it means that the surface of the workpiece is uneven. The surface finish of optical components is characterized by the equation Represented by , where b is the fringe spacing, a is the fringe bending depth or height, and λ is the laser wavelength.

[0125] Calculation process: In order to calculate the depth or height of the stripe pattern, such as Figure 6 Where b is the stripe spacing, a is the stripe bending depth or height, e k and e k+1They are the normal air film thickness corresponding to the kth and k+1th level stripes, and Δe represents the thickness difference of the wedge film corresponding to two adjacent bright (dark) stripes (for air ), when h is the depth of the texture, it corresponds to the presence of depressions on the surface of the workpiece to be measured (such as Figure 6 ), we can get from the relationship between similar triangles: Right now Similarly, when h is the texture height, it corresponds to the presence of protrusions on the surface of the workpiece to be measured (such as Figure 7 ), we can get from the relationship between similar triangles: Right now

[0126] In summary, no matter whether the surface of the workpiece to be measured is concave or convex, the formula can be used Calculate the maximum depth or height h of the texture max , and then compare it with the allowable error h0 we specified in advance, and then judge whether the surface flatness of the workpiece meets the actual requirements.

[0127] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification.

[0128] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. Surface finish automatic detection device, characterized in that: include: An optical platform (1), the optical platform (1) being arranged horizontally and having an upper end surface provided with a strip-shaped positioning through hole (11); A wedge interference mechanism (2); the wedge interference mechanism (2) comprises a standard plane glass slide (21) and a workpiece clamping and positioning mechanism (23) for taking, placing and clamping a workpiece to be measured (22); the standard plane glass slide (21) is arranged perpendicular to the upper end surface of the optical platform (1) and corresponds to one side of the width direction of the strip-shaped positioning through hole (11); the clamping portion of the workpiece clamping and positioning mechanism (23) can clamp the workpiece to be measured (22) to control the workpiece to be measured (22) to be positioned perpendicular to the upper end surface of the optical platform (1) and corresponding to the strip-shaped positioning through hole (11), so that the workpiece to be measured (22) horizontally corresponds to the standard plane glass slide (21) and forms an air wedge (24) with a preset angle, and can drive the workpiece to be measured (22) to descend and pass through the strip-shaped positioning through hole (11); A CCD scanning mechanism (3), the CCD scanning mechanism (3) comprising a light source unit (31) for irradiating the air wedge tip (24) to form an interference fringe image and a CCD scanning detection unit (32) capable of scanning the interference fringe image along a length direction parallel to the strip-shaped positioning through hole (11) to perform a surface finish detection; the light source unit (31) is mounted on the CCD scanning detection unit (32) to move synchronously with the CCD scanning detection unit (32); A sorting mechanism (4); the sorting mechanism (4) is located below the optical platform (1) and corresponds to the strip-shaped positioning through hole (11) to receive the workpiece (22) to be tested that is transported by the workpiece clamping and positioning mechanism (23); the sorting mechanism (4) is electrically connected to the CCD scanning detection unit (32) to classify and transport the workpiece (22) to be tested that has completed the detection according to the detection result.

2. The surface finish automatic detection device according to claim 1, characterized in that: The CCD scanning mechanism (3) comprises a slide rail (33) mounted on the optical platform (1) and arranged along the length direction of the strip-shaped positioning through hole (11) and an electric translation stage (34) slidably connected to the slide rail (33); the CCD scanning detection part (32) horizontally corresponds to the standard plane glass slide (21) and is mounted on the electric translation stage (34) to translate and scan along the length direction of the slide rail (33); the light source part (31) is located on the peripheral side of the CCD scanning detection part (32) and is fixed to the electric translation stage (34) through a connecting rod (35).

3. The surface finish automatic detection device according to claim 2, characterized in that: The wedge interference mechanism (2) also includes a second standard plane glass slide (25), and the second standard plane glass slide (25) and the first standard plane glass slide (21) are arranged on both sides of the width direction of the strip-shaped positioning through hole (11) in a one-to-one correspondence so as to define a detection area between the two; when the workpiece (22) to be measured passes through the detection area, an air wedge (26) having a preset angle 2 is formed between the second standard plane glass slide (25).

4. The surface finish automatic detection device according to claim 3 is characterized in that: The plate surfaces of the second standard plane glass slide (25) and the first standard plane glass slide (21) have the same angle θ with the length direction of the strip-shaped positioning through hole (11).

5. The surface finish automatic detection device according to claim 3 is characterized in that: The CCD scanning mechanism (3) is divided into two groups. The two groups of CCD scanning mechanisms (3) are arranged one by one corresponding to the standard plane glass slide 1 (21) and the standard plane glass slide 2 (25), and are both located outside the standard plane glass slide 1 (21) and the standard plane glass slide 2 (25) in a relative direction, so as to scan and detect the smoothness of the two surfaces of the workpiece (22) to be measured.

6. The surface finish automatic detection device according to claim 3, characterized in that: The wedge-tip interferometer mechanism (2) further comprises a standard glass slide driving mechanism (27) mounted on the optical platform (1), wherein a driving end of the standard glass slide driving mechanism (27) is connected to the standard plane glass slide 1 (21) and the standard plane glass slide 2 (25) to drive the standard plane glass slide 1 (21) and the standard plane glass slide 2 (25) to move along the width direction of the strip-shaped positioning through hole (11) to adjust the horizontal spacing between the standard plane glass slide 1 (21), the standard plane glass slide 2 (25) and the workpiece (22) to be measured.

7. The automatic surface finish detection device according to claim 3 is characterized in that: The workpiece clamping and positioning mechanism (23) comprises a rotating lifting and positioning mechanism (231) which can be laterally moved along the length direction of the strip-shaped positioning through hole (11) and is installed above the optical platform (1), and a workpiece clamp (232) to be measured arranged above the corresponding strip-shaped positioning through hole (11); the workpiece clamp (232) to be measured has a fixed end fixed to the driving end of the rotating lifting and positioning mechanism (231) and a clamping portion for positioning and clamping the workpiece (22) to be measured; the rotating lifting and positioning mechanism (231) can drive the workpiece clamp (232) to be measured to rotate and lift, so as to insert the workpiece (22) to be measured downward into the detection area along a direction perpendicular to the upper end surface of the optical platform (1) to form an air wedge tip 1 (24) and an air wedge tip 2 (26), and can rotate to fine-tune the spatial posture of the workpiece (22) to be measured, thereby adjusting the angles of the preset angle 1 and the preset angle 2.

8. The surface finish automatic detection device according to claim 1, characterized in that: The strip-shaped positioning through hole (11) is rectangular, and a side wall surface of the strip-shaped positioning through hole (11) in the width direction is a positioning wall surface (111) for positioning the workpiece (22) to be measured; a positioning engraved line (12) for locating the position of an end surface of the workpiece (22) to be measured is provided on a side of the upper end surface of the optical platform (1) corresponding to the width direction of the strip-shaped positioning through hole (11).

9. The automatic surface finish detection device according to claim 1, characterized in that: It also includes a control system (5), wherein the control system (5) is electrically connected to the workpiece clamping and positioning mechanism (23) to control the workpiece clamping and positioning mechanism (23) to clamp, move and position the workpiece to be measured (22); The control system (5) is electrically connected to the light source unit (31) and controls the light emission state of the light source unit (31) by turning on and off; The control system (5) is electrically connected to the CCD scanning detection unit (32) to control the CCD scanning detection unit (32) to move and scan at a uniform speed and to process the scanned image information to obtain a detection result; The control system (5) is electrically connected to the sorting mechanism (4) so ​​as to drive and control the sorting mechanism (4) to classify the workpieces (22) to be tested according to the test results.

10. The surface finish automated detection method is characterized by: The device comprises the automatic surface finish detection device as claimed in any one of claims 1 to 9; the detection steps are: Step 1: placing the workpiece to be tested in the detection area: clamping and moving the workpiece to be tested (22) to the top of the strip-shaped positioning through hole (11) and positioning it vertically on the upper end surface of the optical platform (1) by means of the workpiece clamping and positioning mechanism (23), so that the workpiece to be tested (22) horizontally corresponds to the standard plane glass slide (21), and an air wedge (24) is formed between the opposing surfaces of the workpiece to be tested (22) and the standard plane glass slide (21); Step 2: Detecting the surface finish of one side of the workpiece to be measured: starting the CCD scanning mechanism (3) so that the light source part (31) emits light to illuminate the air wedge tip (24) to form an interference fringe image; moving the CCD scanning detection part (32) along the length direction of the parallel strip-shaped positioning through hole (11) to scan the interference fringe image to perform surface finish detection; when the scanning field of view of the CCD scanning detection part (32) completely covers the height of the workpiece to be measured (22) in the height direction, a single lateral scan can complete the surface finish detection of one side of the workpiece to be measured; Step 3: When the scanning field height of the CCD scanning detection unit (32) is less than the height of the workpiece (22) to be measured and the scanning detection of one side of the workpiece (22) cannot be completed by a single lateral scanning, the workpiece (22) to be measured can be controlled by the workpiece clamping and positioning mechanism (23) to descend a preset distance in the direction of the upper end surface of the vertical optical platform (1), and the CCD scanning detection unit (32) is started again to perform lateral scanning until the scanning detection of one side of the workpiece (22) to be measured is completed; Step 4: Sorting according to the test results: The workpiece (22) to be tested is clamped and moved downward by the workpiece clamping and positioning mechanism (23) and passes through the bar-shaped positioning through hole (11) to place the workpiece (22) to be tested on the sorting mechanism (4); the sorting mechanism (4) classifies the tested workpieces (22) to be tested and transports them to different tested workpiece areas according to whether the test results are qualified.

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