CN114923932A

CN114923932A - Defect detection method for uneven grinding of optical glass substrate

Info

Publication number: CN114923932A
Application number: CN202210610385.8A
Authority: CN
Inventors: 李阳; 金虎范; 周阳强
Original assignee: Qingdao Ronghe Intelligent Technology Co Ltd
Current assignee: Qingdao Ronghe Intelligent Technology Co Ltd
Priority date: 2022-05-31
Filing date: 2022-05-31
Publication date: 2022-08-19

Abstract

The invention discloses a defect detection method for uneven grinding of an optical glass substrate, and belongs to the technical field of glass substrates. The technical scheme is as follows: the method comprises the following steps: 1) placing an optical glass substrate on a glass holder; 2) turning on a light source to adjust the brightness, and projecting light to a white background through an optical glass substrate; 3) and analyzing the image projected onto the white background to judge whether the optical glass substrate has the defect of uneven grinding. The invention effectively solves the problem that the grinding of the optical glass substrate is uneven and the detection cannot be effectively carried out, and rapidly finishes the defect detection judgment under the condition of not damaging the surface quality of the optical glass substrate product.

Description

Defect detection method for uneven grinding of optical glass substrate

Technical Field

The invention relates to the technical field of glass substrates, in particular to a defect detection method for uneven grinding of an optical glass substrate.

Background

The production of the optical glass substrate comprises a hot end forming or reheating forming technology, wherein the surface of the glass substrate is in contact with tin liquid, conveying rollers, particles, graphite molds and other substances in the process, so that the defects of scratches, dirt, concave-convex points and the like are caused, and the surface of the optical glass substrate needs to be ground and polished to obtain a high-quality glass surface. The surface grinding of optical glass substrate is a mechanical chemical polishing method, which uses grinding liquid (cerium oxide, calcium carbonate, etc.) to hydrolyze with the surface of glass substrate to generate silicic acid gel layer, and uses the abrasive in the grinding liquid and grinding pad to perform mechanical grinding action to achieve the effect of glass substrate surface finish machining. Common grinding defects such as scratches, dirt, lack points and the like can be accurately detected and judged by matching strong light with human eyes or equipment, but the problem of poor light transmission of a display screen caused by uneven grinding of a glass plate surface due to grinding needs to be solved by a quick and effective inspection method.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the defect detection method for the optical glass substrate grinding unevenness overcomes the defects of the prior art, effectively solves the problem that the optical glass substrate grinding unevenness cannot be effectively detected, and rapidly finishes defect detection judgment under the condition that the surface quality of an optical glass substrate product is not damaged.

The technical scheme of the invention is as follows:

the method for detecting the defects of the optical glass substrate with uneven grinding comprises the following steps:

1) placing an optical glass substrate on a glass support;

2) turning on a light source to adjust the brightness, and projecting light to a white background through an optical glass substrate;

3) and analyzing the image projected onto the white background to judge whether the optical glass substrate has the defect of uneven grinding.

Preferably, in the step 3), the specific analysis mode is as follows: and (3) observing whether the white background has vertical or arc marks by a detector, if so, indicating that the defect of uneven grinding exists on the optical glass substrate, otherwise, indicating that the defect does not exist.

Preferably, in the step 3), the specific analysis mode is as follows: and a CCD lens is arranged above the glass support, picture information collection is carried out on imaging on a white background, and then pixel gray scale judgment is carried out on the collected image.

Preferably, the CCD lens adopts a wide-angle linear CCD lens with a single pixel of 7-10 μm.

Preferably, the light source is a xenon lamp.

Preferably, the glass support is 0.5-1m from the curtain.

Preferably, the detected illuminance at a white background is greater than 80 LUX.

Preferably, the glass support adopts a rotatable glass support.

Preferably, the white background is a white curtain.

Compared with the prior art, the invention has the following beneficial effects:

the invention can realize the rapid inspection and judgment of the uneven grinding defect on the surface of the optical glass substrate and effectively solve the problem that the uneven grinding of the optical glass substrate cannot be effectively detected. And the surface of the glass substrate is not touched in the process, so that the defect detection and judgment can be rapidly finished under the condition of not damaging the surface quality of an optical glass substrate product.

Drawings

In order to more clearly illustrate the embodiments or prior art solutions of the present invention, the drawings used in the description of the embodiments or prior art will be briefly described below, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a schematic diagram of the present invention.

Fig. 2 is a flow chart of the present invention.

In the figure, 1-light source, 2-optical glass substrate, 3-white background.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the technical solution in the embodiment of the present invention will be clearly and completely described below with reference to the drawings in the embodiment of the present invention, and it is obvious that the described embodiment is only a part of the embodiment of the present invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, shall fall within the protection scope of the present invention.

As shown in fig. 1, the detection flow of the apparatus used in the detection method of the present invention is shown in fig. 2:

1) the detection environment is required to be a darkroom, no external light source enters after a door or window and a light source are closed, the wall, the glass support and the white background 3 do not reflect light, then the light source 1, the glass support and the white background are sequentially placed, the distance between the glass support and the curtain can be determined according to the actual observation effect, and the optimal distance is 0.5-1 m;

2) placing an optical glass substrate 2 on a glass support, turning on a light source 1 to adjust the brightness, and projecting light onto a white background 3 (such as a white curtain) through the optical glass substrate 2; preferably, the light source 1 adopts a xenon lamp; preferably, the detected illumination intensity at the curtain is greater than 80LUX, so that defect marks can be observed clearly;

3) the inspector analyzes the image projected onto the white background 3 and determines whether the optical glass substrate 2 has a defect of uneven grinding.

Wherein, the analysis mode of step 3) may be: and observing whether the white background 3 has vertical or arc marks, if so, indicating that the defect of uneven grinding exists on the optical glass substrate 2, otherwise, indicating that the defect does not exist. The optical glass substrate 2 is used as a low-stress amorphous inorganic non-metallic material, and has the characteristics of high transmittance and low reflectivity in the glass material, foreign matters reflect obviously when being irradiated on the optical glass substrate, and the image is uniformly formed on a white curtain when being formed on the white curtain through the optical glass substrate, so that the display of display screens such as LCD, OLED and the like is not influenced; if the surface of the optical glass substrate is unevenly ground, light rays are refracted through the glass substrate, and the form displayed on the white curtain is obviously different from the normal glass substrate in the front and inclined viewing angles.

Or, the analysis mode of the step 3) is as follows: and a CCD lens is arranged above the glass bracket, picture information collection is carried out on the image on the white background 3, and then pixel gray scale judgment is carried out on the collected image. The principle of its utilization is: the gray scales of the CCD collected images of the uniformly ground products are uniform, the whole gray scale changes are consistent, and the gray scales of the CCD collected images of the non-uniformly ground products are different. According to the general defect size control requirements of the optical glass substrate 2, w (width) is less than 0.1mm, L (length) is less than 1mm, and when the gray scale contrast in the image collected by the CCD is obviously different and the abnormal pixel size reaches w (width) is more than or equal to 0.1mm, L is more than or equal to 1mm, the defect of uneven grinding of the optical glass substrate 2 is indicated.

Furthermore, the rotatable glass support is adopted as the glass support, the grade judgment is carried out according to the angle of the rotatable glass support required by a customer or in the industry specification, and the waste caused by product misjudgment is avoided.

Although the present invention has been described in detail by referring to the drawings in connection with the preferred embodiments, the present invention is not limited thereto. Various equivalent modifications or substitutions can be made on the embodiments of the present invention by those skilled in the art without departing from the spirit and scope of the present invention, and these modifications or substitutions are within the scope of the present invention/any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. The method for detecting the defects of the optical glass substrate with uneven grinding is characterized by comprising the following steps of:

1) placing an optical glass substrate (2) on a glass support;

2) turning on a light source (1) to adjust the brightness, and projecting light onto a white background (3) through an optical glass substrate (2);

3) the image projected on the white background (3) is analyzed to judge whether the defect of uneven grinding exists on the optical glass substrate (2).

2. The method for detecting defects caused by non-uniform polishing of an optical glass substrate according to claim 1, wherein in the step 3), the specific analysis method is as follows: and (3) observing whether the white background (3) has vertical or arc marks by a detector, if so, indicating that the defect of uneven grinding exists on the optical glass substrate (2), otherwise, indicating that the defect does not exist.

3. The method for detecting defects of uneven polishing of an optical glass substrate according to claim 1, wherein in the step 3), the specific analysis method is as follows: a CCD lens is arranged above the glass bracket, image information collection is carried out on imaging on the white background (3), and then pixel gray scale judgment is carried out on the collected image.

4. The method of claim 3, wherein the CCD lens is a wide-angle linear CCD lens having 7-10 μm pixels.

5. The method for detecting defects of uneven polishing of an optical glass substrate as claimed in claim 1, wherein said light source (1) employs a xenon lamp.

6. The method of claim 1, wherein the glass holder is spaced from the screen by 0.5 to 1 m.

7. A method for detecting defects in grinding irregularities of an optical glass substrate as claimed in claim 1, wherein the detection illuminance at a white background is greater than 80 LUX.

8. The method for detecting defects of polishing unevenness of an optical glass substrate according to claim 1, wherein the glass holder is a rotatable glass holder.

9. The method for detecting defects of polishing unevenness of an optical glass substrate as claimed in claim 1, wherein a white curtain is used as the white background (3).