Device and method for detecting positions and sizes of inclusions in quartz glass

Abstract

The invention provides a device and a method for detecting positions and sizes of inclusions in quartz glass. The device comprises a clamping tool, a white light source, a camera, a three-dimensional guide rail and a computer, the clamping tool is used for clamping detected quartz glass; the white light source is positioned on one side of the quartz glass and irradiates white light to the light passing surface of the quartz glass; the camera is positioned on the other side of the quartz glass and faces the light-passing surface of the quartz glass; the three-dimensional guide rail is connected with the camera and used for moving the camera; the computer obtains images shot by the camera and controls the three-dimensional guide rail to move the camera. The method realizes accurate identification of the position and the size of the inclusion in the quartz glass, and is suitable for large-size quartz glass ingots.

Description

Technical Field

[0001] The invention relates to the technical field of quartz glass detection, and in particular to a device and method for detecting the position and size of inclusions inside quartz glass. Background Art

[0002] During the manufacturing process, quartz glass will produce inclusions such as bubbles and stones. These inclusions will change the optical properties of the micro-region, causing the optical performance of quartz glass to deteriorate, thus affecting its normal use, especially affecting its application in the field of high-energy lasers. 3 The total cross-sectional area of ​​inclusions in the glass divides the glass into five grades. The test method for inclusions is carried out in accordance with the standard GB / T 7962.8-2010. This method uses the reflection and scattering of light by inclusions such as bubbles and stones in the glass to illuminate the glass to be tested from the side, with a black screen as the background, and observes it with the human eye. On the one hand, this method is not accurate enough and cannot accurately identify the size and position of inclusions; on the other hand, human eye observation is inevitably prone to fatigue and false detection, which is not suitable for high-precision detection. The standard GB / T 5949-2014 uses a magnifying projector combined with a workbench with adjustable focal length to detect bubbles and gas lines inside the glass. This method improves accuracy and can more accurately determine the size of inclusions and their depth relative to the surface, but it still requires manual detection, which is time-consuming and labor-intensive, and it is difficult to detect oversized quartz glass ingots (diameter over 500mm). In addition, both methods require that the light-transmitting surface of the glass being inspected is transparent, otherwise it should be mechanically polished. For finely milled but unpolished quartz glass, its light-transmitting surface is not transparent, and both methods make it difficult to detect the size and position of internal inclusions. Summary of the invention

[0003] The object of the present invention is to provide a device and method for detecting the position and size of inclusions inside quartz glass, so as to achieve accurate detection of the position and size of inclusions inside quartz glass.

[0004] In order to solve the above technical problems, the present invention provides a device for detecting the position and size of inclusions inside quartz glass, including a clamping tool, a white light source, a camera, a three-dimensional guide rail, and a computer; The clamping tool is used to clamp the quartz glass to be inspected; The white light source is located on one side of the quartz glass, irradiating white light to the light-transmitting surface of the quartz glass; The camera is located on the other side of the quartz glass and faces the light-transmitting surface of the quartz glass; The three-dimensional guide rail is connected to the camera and is used to move the camera; The computer acquires the images taken by the camera and controls the three-dimensional guide rail to move the camera. According to the above scheme, the three-dimensional guide rail has X-axis, Y-axis and Z-axis moving directions, the X-axis and Y-axis are horizontal directions, the Z-axis is vertical direction, and the X-axis and Z-axis are parallel to the light-transmitting surface of the quartz glass, and the Y-axis is perpendicular to the light-transmitting surface of the quartz glass.

[0005] According to the above scheme, the focal plane of the camera is parallel to the light-transmitting surface of the quartz glass.

[0006] A method for detecting the position and size of inclusions inside quartz glass, the method is implemented based on the device for detecting the position and size of inclusions inside quartz glass as described above, comprising: S1. Fix the quartz glass to be inspected on the clamping fixture; S2. Clean the light-transmitting surface of the quartz glass; S3, moving the camera perpendicular to the light-transmitting surface of the quartz glass to change the depth layer photographed by the camera; S4, moving the camera parallel to the light-transmitting surface of the quartz glass to capture an image of a certain depth layer of the quartz glass; S5, looping S3-S4 until all images of the depth layers of the quartz glass are captured; S6. Determine the size and depth of the inclusions based on the image.

[0007] According to the above scheme, step S1 includes adjusting the clamping fixture so that the light-transmitting surface of the quartz glass is parallel to the focal plane of the camera.

[0008] According to the above scheme, use a dust-free cloth dipped in a small amount of a mixture of anhydrous ethanol and ether, and wipe the front and back light-transmitting surfaces of the quartz glass in the same direction to ensure that no stains are left while cleaning the light-transmitting surfaces.

[0009] According to the above scheme, the volume ratio of ethanol and ether in the mixed solution is 1:1.

[0010] According to the above scheme, if the quartz glass to be inspected has been finely milled but not polished, step S2 includes: after the light-through surface is cleaned, the light-through surface of the quartz glass is wiped with a dust-free cloth soaked in liquid paraffin to form a uniform, stable and translucent oil film on the light-through surface.

[0011] According to the above scheme, the method of wiping the light-transmitting surface of quartz glass with a dust-free cloth soaked in liquid paraffin includes: first folding the dust-free cloth, dripping a certain amount of liquid paraffin on the dust-free cloth to fully soak the dust-free cloth; then unfolding the dust-free cloth, and using the inner layer of the dust-free cloth to evenly wipe the light-transmitting surface in a single direction.

[0012] According to the above scheme, executing steps S3 to S5 once is a single detection, and step S6 includes: determining the size and depth of the inclusions based on images obtained from at least three detections.

[0013] Beneficial Effects The present invention realizes automatic detection of quartz glass by setting up cameras and three-dimensional guide rails. Compared with traditional human eye detection, the detection of the device is more suitable for large-diameter quartz glass, and can effectively avoid false detection and missed detection caused by human eye fatigue during detection. In addition, the camera moves during the detection process while the quartz glass does not move, reducing the risk of the quartz glass falling or bumping.

[0014] Furthermore, the present invention uses a mixed liquid with a specific ratio for cleaning, which leaves fewer stains after wiping and has a better cleaning effect than the existing cleaning method of using only anhydrous ethanol. The cleaning method has a lower cost than ultrasonic cleaning and is easy to clean large-sized quartz glass. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Schematic diagram of a device for detecting the position and size of inclusions inside quartz glass according to Embodiment 1 of the present invention; Figure 2 This is a flow chart of a device and method for detecting the position and size of inclusions inside quartz glass according to the second embodiment of the present invention; Figure 3~Figure 6 This is the bubble image of the second embodiment of the present invention.

[0016] In the figure: 1- white light source, 2- quartz glass, 3- clamping tooling, 4- camera, 5- 3D guide rail. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0018] Embodiment 1: This embodiment provides a device for detecting the position and size of inclusions inside a quartz glass 2, comprising a clamping tool 3, a white light source 1, a camera 4, a three-dimensional guide rail 5, and a computer; The clamping tool 3 is used for clamping the quartz glass 2 to be inspected; The white light source 1 is located on one side of the quartz glass 2 and irradiates white light to the light-transmitting surface of the quartz glass 2 (the white light penetrates the quartz glass 2 and illuminates the field of view of the camera 4); The camera 4 is located on the other side of the quartz glass 2 and faces the light-transmitting surface of the quartz glass 2; The three-dimensional guide rail 5 is connected to the camera 4 and is used to move the camera 4; The computer acquires the image taken by the camera 4 and controls the three-dimensional guide rail 5 to move the camera 4 . The device of this embodiment is suitable for high-precision detection of the size and position of inclusions inside large-sized quartz glass 2 (ingot); if the quartz glass 2 is cylindrical, then the diameter of its light-transmitting surface is greater than 500 mm and is considered to be large; if the quartz glass 2 is a rectangular parallelepiped, then the diagonal length of its light-transmitting surface is greater than 500 mm and is considered to be large.

[0019] Furthermore, the three-dimensional guide rail 5 has X-axis, Y-axis, and Z-axis moving directions, the X-axis and Y-axis are horizontal directions, the Z-axis is vertical direction, and both the X-axis and Z-axis are parallel to the light-transmitting surface of the quartz glass 2, and the Y-axis is perpendicular to the light-transmitting surface of the quartz glass 2.

[0020] Furthermore, the focal plane of the camera 4 is parallel to the light-transmitting surface of the quartz glass 2 .

[0021] Embodiment 2: The principles of this embodiment are basically the same as those of the first embodiment. On the basis of the first embodiment, this embodiment provides a method for detecting the position and size of inclusions inside the quartz glass 2. The method is implemented based on the above-mentioned device for detecting the position and size of inclusions inside the quartz glass 2, and includes: S1, fixing the quartz glass 2 to be inspected on the clamping tool 3; S2, cleaning the light-transmitting surface of the quartz glass 2; S3, moving the camera 4 perpendicular to the light-transmitting surface of the quartz glass 2 to change the depth layer photographed by the camera 4; S4, moving the camera 4 parallel to the light-transmitting surface of the quartz glass 2 to capture an image of a certain depth layer of the quartz glass 2; S5, looping S3-S4 until all images of the depth layers of the quartz glass 2 are captured; S6. Determine the size and depth of the inclusions based on the image.

[0022] Furthermore, step S1 includes adjusting the clamping fixture 3 (ie, adjusting the pitch and rotation angle of the quartz glass 2 ) so that the light-transmitting surface of the quartz glass 2 is parallel to the focal plane of the camera 4 .

[0023] Furthermore, a small amount of a mixture of anhydrous ethanol and ether is dipped into a dust-free cloth, and the front and rear light-transmitting surfaces of the quartz glass 2 are wiped in the same direction to ensure that no traces are left while cleaning the light-transmitting surfaces.

[0024] Furthermore, the volume ratio of ethanol to ether in the mixed solution is 1:1.

[0025] Furthermore, if the quartz glass 2 to be inspected has been finely milled but not polished, step S2 includes: after the light-through surface is cleaned, wiping the light-through surface of the quartz glass 2 with a dust-free cloth soaked in liquid paraffin, so that a uniform, stable and light-transmitting oil film is formed on the light-through surface; the liquid paraffin has a low viscosity and is not easy to volatilize, and the formed oil film is uniform, stable and light-transmitting, thereby realizing the detection of the finely milled but unpolished quartz glass 2.

[0026] Furthermore, the method of wiping the light-transmitting surface of the quartz glass 2 with a dust-free cloth soaked in liquid paraffin includes: first folding the dust-free cloth, dripping a certain amount of liquid paraffin on the dust-free cloth to fully soak the dust-free cloth; then unfolding the dust-free cloth, and using the inner layer of the dust-free cloth to evenly wipe the light-transmitting surface in a single direction; this method can make the oil film generated during application more uniform, introduce less pollutants, and is not easy to form oil droplets, thereby achieving better light transmission performance.

[0027] Further, executing steps S3 to S5 once is a single detection, and step S6 includes: determining the size and depth of the inclusions based on images obtained from at least three detections.

[0028] To illustrate the effects of the device and method used in the present invention, examples are given below.

[0029] Example 1: For a polished quartz glass ingot with a light-transmitting surface size of 50mm*100mm and a thickness of 63mm, manual inspection and equipment inspection were used for comparison.

[0030] Since the glass being tested was relatively thick, the manual inspection was performed using the method in standard GB / T 7962.8-2010 and was conducted by two people. Ultimately, both people detected two bubbles inside the glass being tested. Due to the limitations of the method, they could only determine the location of the bubbles, but could not determine their depth and size.

[0031] The device of the present invention is then used to detect the inspected glass, and finally 6 bubbles are detected inside the inspected glass. After analyzing the data, it is found that the 6 bubbles can be divided into 2 groups according to the bubble positions, wherein the first group has 1 bubble and the second group has 5 bubbles, respectively. Figure 3 , Figure 4 As shown. The positions of these two groups of bubbles are consistent with the positions of the two bubbles detected manually. The reason for the inconsistency in number is that the positions of the five bubbles in the second group are very close, and it is difficult to distinguish multiple bubbles during manual detection, so they are mistakenly judged as one bubble. In addition, the depth and size of these two groups of bubbles were also detected using the equipment: the depth of a single bubble in the first group was 9.00 mm from the front surface and the diameter was 66 μm; the depth of multiple bubbles in the second group was 45.75 mm from the front surface, and the largest bubble had a diameter of 100 μm.

[0032] Example 2: For a piece of finely milled but unpolished quartz glass ingot with a light-transmitting surface size of 60mm*60mm and a thickness of 78mm, manual inspection and equipment inspection were used for comparison.

[0033] Since the glass under test was thick and unpolished, liquid paraffin was smeared on the surface of the glass under test during manual inspection. Then the inspection was carried out according to the method in standard GB / T 7962.8-2010 and performed by two people. In the end, both of them detected a bubble inside the glass under test. Due to the limitation of the method, they could only determine the position of the bubble, but could not determine the depth and size of the bubble.

[0034] After that, the glass under test was tested using an integrated testing device. The test was performed three times according to the above process. Through comparative analysis of the results of the three tests, it was finally determined that there were two bubbles inside the glass under test. Figure 5 , Figure 6 As shown in the figure, the first bubble is 38.25 mm from the front surface and has a diameter of 6 μm; the second bubble is 40.50 mm from the front surface and has a diameter of ≤5 μm. After analyzing the data, it was found that the position of the first bubble was consistent with a bubble detected manually, while the second bubble was not detected manually because the size of the second bubble was too small, reaching the limit of human eye resolution, and the inspected glass was not polished, making detection difficult, so it was missed manually.

[0035] It should be pointed out that, according to the needs of implementation, the various steps / components described in this application can be split into more steps / components, and two or more steps / components or partial operations of steps / components can be combined into new steps / components to achieve the purpose of the present invention.

[0036] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for detecting the position and size of inclusions inside quartz glass, characterized in that: Including clamping tooling, white light source, camera, three-dimensional guide rail, computer; The clamping tool is used to clamp the quartz glass to be inspected; The white light source is located on one side of the quartz glass, irradiating white light to the light-transmitting surface of the quartz glass; The camera is located on the other side of the quartz glass and faces the light-transmitting surface of the quartz glass; The three-dimensional guide rail is connected to the camera and is used to move the camera; The computer acquires the images taken by the camera and controls the three-dimensional guide rail to move the camera.

2. The device for detecting the position and size of inclusions in quartz glass according to claim 1, characterized in that: The three-dimensional guide rail has X-axis, Y-axis and Z-axis moving directions, the X-axis and Y-axis are horizontal directions, the Z-axis is vertical direction, and the X-axis and Z-axis are parallel to the light-transmitting surface of the quartz glass, while the Y-axis is perpendicular to the light-transmitting surface of the quartz glass.

3. The device for detecting the position and size of inclusions in quartz glass according to claim 1, characterized in that: The focal plane of the camera is parallel to the light-transmitting surface of the quartz glass.

4. A method for detecting the position and size of inclusions inside quartz glass, characterized in that: The method is implemented based on the device for detecting the position and size of inclusions inside quartz glass according to any one of claims 1 to 3, and comprises: S1. Fix the quartz glass to be inspected on the clamping fixture; S2. Clean the light-transmitting surface of the quartz glass; S3, moving the camera perpendicular to the light-transmitting surface of the quartz glass to change the depth layer photographed by the camera; S4, moving the camera parallel to the light-transmitting surface of the quartz glass to capture an image of a certain depth layer of the quartz glass; S5, looping S3-S4 until all images of the depth layers of the quartz glass are captured; S6. Determine the size and depth of the inclusions based on the image.

5. The method for detecting the position and size of inclusions in quartz glass according to claim 4, characterized in that: Step S1 includes adjusting the clamping fixture so that the light-transmitting surface of the quartz glass is parallel to the focal plane of the camera.

6. The method for detecting the position and size of inclusions in quartz glass according to claim 4, characterized in that: Use a dust-free cloth dipped in a small amount of a mixture of anhydrous ethanol and ether, and wipe the front and back light-transmitting surfaces of the quartz glass in the same direction, making sure to clean the light-transmitting surfaces without leaving any stains.

7. The method for detecting the position and size of inclusions in quartz glass according to claim 6, characterized in that: The volume ratio of ethanol to ether in the mixed solution is 1:

1.

8. The method for detecting the position and size of inclusions in quartz glass according to claim 6, characterized in that: If the quartz glass to be inspected has been finely milled but not polished, step S2 includes: after the light-through surface is cleaned, the light-through surface of the quartz glass is wiped with a dust-free cloth soaked in liquid paraffin to form a uniform, stable and translucent oil film on the light-through surface.

9. The method for detecting the position and size of inclusions in quartz glass according to claim 8, characterized in that: The method for wiping the light-transmitting surface of quartz glass with a dust-free cloth soaked in liquid paraffin comprises: firstly folding the dust-free cloth, dripping a certain amount of liquid paraffin on the dust-free cloth to fully soak the dust-free cloth; then unfolding the dust-free cloth, and using the inner layer of the dust-free cloth to evenly wipe the light-transmitting surface in a single direction.

10. The method for detecting the position and size of inclusions in quartz glass according to claim 4, characterized in that: Executing steps S3 to S5 once is a single detection, and step S6 includes: determining the size and depth of the inclusions based on images obtained from at least three detections.

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