阅读说明：本技术 玻璃应力缺陷的检测方法和装置 (The detection method and device of glass strain defect ) 是由 黄继欣 王昌奇 王大鹏 于 2018-05-25 设计创作，主要内容包括：本发明涉及玻璃应力缺陷的检测方法和装置。所述方法包括：使线偏振光依次通过玻璃样品、四分之一波片和检偏镜,其中线偏振光的偏振方向与检偏镜的偏振轴正交；当四分之一波片的光轴处于第一角度时采集玻璃样品的第一成像,第一角度为四分之一波片的光轴相对于线偏振光的偏振方向与检偏镜的偏振轴的45度角平分线的角度；当四分之一波片的光轴处于第二角度时采集玻璃样品的第二成像,第二角度与第一角度的大小相等、符号相反；获取第一成像的灰度值与第二成像的灰度值；以及根据第一成像的灰度值与第二成像的灰度值确定玻璃样品是否存在应力缺陷。采用本发明的方法和装置能够减轻甚至消除玻璃表面瑕疵或尘埃干扰,快速可靠地检测玻璃的应力缺陷。(The present invention relates to the detection method of glass strain defect and devices.The described method includes: linearly polarized light is made to pass sequentially through glass sample, quarter-wave plate and analyzer, wherein the polarization direction of linearly polarized light and the polarization axle of analyzer are orthogonal；The first imaging of glass sample is acquired when the optical axis of quarter-wave plate is in first angle, first angle is angle of the optical axis of quarter-wave plate relative to the polarization direction of linearly polarized light and 45 degree of angular bisectors of the polarization axle of analyzer；The second imaging of glass sample is acquired when the optical axis of quarter-wave plate is in second angle, second angle is opposite with the equal in magnitude of first angle, symbol；Obtain the gray value of the first imaging and the gray value of the second imaging；And determine glass sample with the presence or absence of stress defect according to the gray value of the first imaging and the gray value of the second imaging.It can reduce using methods and apparatus of the present invention and even be eliminated glass surface flaw or dust interference, detect the stress defect of glass fast and reliablely.)

1. a kind of detection method of glass strain defect, which is characterized in that the described method includes:

Linearly polarized light is set to pass sequentially through glass sample, quarter-wave plate and analyzer, wherein the polarization side of the linearly polarized light To orthogonal with the polarization axle of the analyzer；

First that the glass sample is acquired when the optical axis of the quarter-wave plate is in first angle is imaged, and described first Angle is the optical axis of the quarter-wave plate relative to the polarization direction of the linearly polarized light and the polarization axle of the analyzer 45 degree of angular bisectors angle；

Second that the glass sample is acquired when the optical axis of the quarter-wave plate is in second angle is imaged, and described second Angle is opposite with the equal in magnitude of the first angle, symbol；

Obtain the gray value of first imaging and the gray value of second imaging；And

It determines that the glass sample whether there is according to the gray value of the gray value of first imaging and second imaging to answer Power defect.

2. detection method according to claim 1, which is characterized in that the gray value and institute according to first imaging The gray value for stating the second imaging determines on the glass sample with the presence or absence of stress defect, comprising:

According to it is described first imaging gray value and it is described second imaging gray value to it is described first imaging with it is the second one-tenth described It include defect abnormal area in the third imaging to generate third imaging as being filtered processing and noise reduction process；And

According to the defect abnormal area it is described first imaging in corresponding gray value with it is described second be imaged in corresponding ash Angle value determines whether the defect abnormal area is stress defect area.

3. detection method according to claim 2, which is characterized in that the gray value and institute according to first imaging It states the gray value of the second imaging and processing and noise reduction process is filtered to first imaging and second imaging, to generate the Three are imaged, and include defect abnormal area in the third imaging, comprising:

The gray value of gray value and second imaging that described first is imaged carries out difference operation, after obtaining filtration treatment Imaging；

Process of convolution is carried out to the imaging after the filtration treatment, to obtain the imaging after noise reduction process；

Binary conversion treatment is carried out to the imaging after the noise reduction process, with the determination defect abnormal area, and generates described the Three imagings.

4. detection method according to claim 2, which is characterized in that it is described according to the defect abnormal area described Corresponding gray value determines whether the defect abnormal area is to answer with corresponding gray value in second imaging in one imaging Power defect area, comprising:

By the defect abnormal area in first imaging corresponding gray scale in the second imaging described in corresponding sum of the grayscale values Value is compared:

If the defect abnormal area corresponding gray scale in the second imaging described in corresponding sum of the grayscale values in first imaging The absolute value of difference between value meets preset condition, then determines the defect abnormal area for stress defect area；Otherwise sentence The fixed defect abnormal area is not stress defect area.

5. according to detection method described in claims 1-4, which is characterized in that the linearly polarized light is issued by white light source Light incidence is generated by polarizer, and the polarization axle of the polarizer is orthogonal with the polarization axle of the analyzer.

6. a kind of detection device of glass strain defect, described device make linearly polarized light pass sequentially through glass sample, a quarter Wave plate and analyzer, wherein the polarization direction of the linearly polarized light is orthogonal with the polarization axle of the analyzer；It is characterized in that institute Stating device includes:

First imaging acquisition module, for acquiring the glass sample when the optical axis of quarter-wave plate is in first angle First imaging, the first angle are polarization direction and the inspection of the optical axis of quarter-wave plate relative to the linearly polarized light The angle of 45 degree of angular bisectors of the polarization axle of polariscope；

Second imaging acquisition module, for acquiring the glass sample when the optical axis of quarter-wave plate is in second angle Second imaging, the second angle are opposite with the equal in magnitude of the first angle, symbol；

Gray value obtains module, for obtaining the gray value of first imaging and the gray value of second imaging；

Stress determining defects module, for determining institute according to the gray value of first imaging and the gray value of second imaging It states on glass sample with the presence or absence of stress defect.

7. detection device according to claim 6, which is characterized in that the stress determining defects module includes:

Generation unit is imaged in third, and the gray value for being imaged according to the gray value of first imaging and described second is to described First imaging is filtered processing and noise reduction process with second imaging, to generate third imaging, wraps in the third imaging Include defect abnormal area；

Judging unit, for according to the defect abnormal area in first imaging corresponding gray value and the second one-tenth described Corresponding gray value determines whether the defect abnormal area is stress defect area as in.

8. detection device according to claim 7, which is characterized in that the third imaging generation unit is specifically used for:

The gray value of gray value and second imaging that described first is imaged carries out difference operation, after obtaining filtration treatment Imaging；

Process of convolution is carried out to the imaging after the filtration treatment, to obtain the imaging after noise reduction process；

Binary conversion treatment is carried out to the imaging after the noise reduction process, with the determination defect abnormal area, and generates described the Three imagings.

9. detection device according to claim 7, which is characterized in that the judging unit is specifically used for:

By the defect abnormal area in first imaging corresponding gray scale in the second imaging described in corresponding sum of the grayscale values Value is compared；

If the defect abnormal area corresponding gray scale in the second imaging described in corresponding sum of the grayscale values in first imaging The absolute value of difference between value meets preset condition, then determines the defect abnormal area for stress defect area；Otherwise sentence The fixed defect abnormal area is not stress defect area.

10. according to detection device described in claims 6-9, which is characterized in that the linearly polarized light is issued by white light source Light incidence generated by polarizer, the polarization axle of the polarizer is orthogonal with the polarization axle of the analyzer.

Technical field

The present invention relates to stress mornitoring fields, relate more specifically to the detection method and device of glass strain defect.

Background technique

Under normal conditions, since the various techniques in process influence, meeting residual stress in glass plate, and stress is big Small is the major criterion for measuring glass quality；If stress is larger, service performance to glass plate and can be made using safe At obvious serious influence.Therefore, the stress mornitoring of glass is particularly important.

Currently, detection glass strain defect mainly carries out by the following method: linearly polarized light being made to pass sequentially through sample, four points One of wave plate and analyzer, then lean on human eye or computer picture recognition, determine the stress of sample interior.Its testing principle is: If linearly polarized light can generate birefringent, two beam polarization directions of formation under the action of stress there are stress defect in sample Orthogonal and different direction of propagation light beam, the two-beam after quarter-wave plate and analyzer by interfering, shape At stress line, thus according to stress line test sample stress.However, the dust or flaw due to sample surfaces interfere, stress line Judgement poor reliability, and low efficiency, repeatability is bad, is unfavorable for typical products in mass production detection.

Summary of the invention

Based on this, it is necessary to which in view of the above technical problems, providing one kind can reliably determine that the glass of stress defect is answered The detection method and device of power defect.

A kind of detection method of glass strain defect, this method comprises:

Linearly polarized light is set to pass sequentially through glass sample, quarter-wave plate and analyzer, wherein the polarization side of linearly polarized light To orthogonal with the polarization axle of analyzer；

The first imaging of glass sample, first angle four are acquired when the optical axis of quarter-wave plate is in first angle Angle of the optical axis of/mono- wave plate relative to the polarization direction of linearly polarized light and 45 degree of angular bisectors of the polarization axle of analyzer；

The second imaging of glass sample, second angle and the are acquired when the optical axis of quarter-wave plate is in second angle The equal in magnitude of one angle, symbol are opposite；

Obtain the gray value of the first imaging and the gray value of the second imaging；And

Determine glass sample with the presence or absence of stress defect according to the gray value of the gray value of the first imaging and the second imaging.

Glass sample is determined according to the gray value of the gray value of the first imaging and the second imaging in one of the embodiments, It is upper to whether there is stress defect, comprising:

Place is filtered to the first imaging and the second imaging according to the gray value of the first imaging and the gray value of the second imaging Reason and noise reduction process include defect abnormal area in third imaging to generate third imaging；And

According to defect abnormal area, corresponding gray value and corresponding gray value in the second imaging are determining in the first imaging Whether defect abnormal area is stress defect area.

In one of them embodiment, it is imaged according to the gray value of the gray value of the first imaging and the second imaging to first It is filtered processing and noise reduction process with the second imaging, includes defect abnormal area, packet in third imaging to generate third imaging It includes:

By first imaging gray value with second imaging gray value carry out difference operation, with obtain filter treated at Picture；

Process of convolution is carried out to the imaging after filtration treatment, to obtain the imaging after noise reduction process；

Binary conversion treatment is carried out to the imaging after noise reduction process, to determine defect abnormal area, and generates third imaging.

In one of them embodiment, according to defect abnormal area in the first imaging corresponding gray value and the second one-tenth Corresponding gray value determines whether defect abnormal area is stress defect area as in, comprising:

By defect abnormal area, corresponding gray value compares in the corresponding imaging of sum of the grayscale values second in the first imaging Compared with；

If defect abnormal area is in corresponding sum of the grayscale values second in the first imaging is imaged between corresponding gray value The absolute value of difference meets preset condition, then determines the defect abnormal area for stress defect area；Otherwise determine that the defect is different Normal region is not stress defect area.

In one of them embodiment, the light incidence that linearly polarized light is issued by white light source is generated by polarizer, The polarization axle of polarizer and the polarization axle of analyzer are orthogonal.

A kind of detection device of glass strain defect, the device make linearly polarized light pass sequentially through glass sample, a quarter Wave plate and analyzer, wherein the polarization direction of linearly polarized light and the polarization axle of analyzer are orthogonal；The device includes:

First imaging acquisition module, for acquiring glass sample when the optical axis of quarter-wave plate is in first angle First imaging, first angle are the optical axis of quarter-wave plate relative to the polarization direction of linearly polarized light and the polarization axle of analyzer 45 degree of angular bisectors angle；

Second imaging acquisition module, for acquiring glass sample when the optical axis of quarter-wave plate is in second angle Second imaging, second angle are opposite with the equal in magnitude of first angle, symbol；

Gray value obtains module, for obtaining the gray value of the first imaging and the gray value of the second imaging；

Stress determining defects module, for determining hyaloid according to the gray value of the first imaging and the gray value of the second imaging It whether there is stress defect on product.

In one of them embodiment, stress determining defects module includes:

Generation unit is imaged in third, for being imaged according to the gray value of the first imaging and the gray value of the second imaging to first It is filtered processing and noise reduction process with the second imaging, includes defect abnormal area in third imaging to generate third imaging；

Judging unit, for corresponding gray value to be corresponding with the second imaging in the first imaging according to defect abnormal area Gray value determine whether defect abnormal area is stress defect area.

In one of them embodiment, third imaging generation unit is specifically used for:

By first imaging gray value with second imaging gray value carry out difference operation, with obtain filter treated at Picture；

Process of convolution is carried out to the imaging after filtration treatment, to obtain the imaging after noise reduction process；

Binary conversion treatment is carried out to the imaging after noise reduction process, to determine defect abnormal area, and generates third imaging.

In one of them embodiment, judging unit is specifically used for:

By defect abnormal area, corresponding gray value compares in the corresponding imaging of sum of the grayscale values second in the first imaging Compared with；

If defect abnormal area is in corresponding sum of the grayscale values second in the first imaging is imaged between corresponding gray value The absolute value of difference meets preset condition, then determines defect abnormal area for stress defect area；Otherwise determine defect exceptions area Domain is not stress defect area.

In one of them embodiment, the light incidence that linearly polarized light is issued by white light source is generated by polarizer, The polarization axle of polarizer and the polarization axle of analyzer are orthogonal.

The detection method and device of above-mentioned glass strain defect, by being respectively relative to linearly polarized light in quarter-wave plate Polarization direction and analyzer polarization axle angular bisector at first angle and second angle when, acquire the first of glass sample Imaging and the second imaging simultaneously determine stress defect according to the gray value of the first imaging and the second imaging, can reduce and even are eliminated sample The dust on product surface interferes, and detects glass strain defect fast and reliablely, and reproducible, is able to carry out the inspection of typical products in mass production It surveys.

Detailed description of the invention

The preferred rather than embodiment of limitation of the invention will be described with reference to attached drawing by way of example, in which:

Fig. 1 shows the application environment schematic diagram of the detection method of glass strain defect in one embodiment；

Fig. 2 shows the flow charts of the detection method of glass strain defect in one embodiment；

Fig. 3 shows the flow chart of the detection method of glass strain defect in another embodiment；

Fig. 4 shows the flow chart of the detection method of glass strain defect in another embodiment；

Fig. 5 shows the flow chart of the detection method of glass strain defect in further embodiment；

Fig. 6 A-6C shows the first imaging, the second imaging and processing of the glass sample obtained according to the detection method of Fig. 5 The third imaging obtained afterwards；

Fig. 7 shows the schematic diagram of the detection device of glass strain defect in one embodiment；

Fig. 8 shows the schematic diagram of internal structure of the stress determining defects module in Fig. 7.

Specific embodiment

In order to make the foregoing objectives, features and advantages of the present invention clearer and more comprehensible, with reference to the accompanying drawing to the present invention Specific embodiment be described in detail.Many details are explained in the following description in order to fully understand this hair It is bright.But the invention can be embodied in many other ways as described herein, those skilled in the art can be not Similar improvement is done in the case where violating intension of the present invention, therefore the present invention is not limited to the specific embodiments disclosed below.

Unless otherwise defined, all technical and scientific terms used herein and belong to technical field of the invention The normally understood meaning of technical staff is identical.Term as used herein in the specification of the present invention is intended merely to description tool The purpose of the embodiment of body, it is not intended that in the limitation present invention.Each technical characteristic of above embodiments can carry out arbitrary group It closes, for simplicity of description, combination not all possible to each technical characteristic in above-described embodiment is all described, however, As long as there is no contradiction in the combination of these technical features, all should be considered as described in this specification.

The detection method of glass strain defect provided by the embodiments of the present application can be applied to application ring as shown in Figure 1 In border.In Fig. 1, be followed successively by from top to bottom by rack (not shown) fix with lower component: the detection of glass strain defect dress Set 110, camera lens 120, analyzer 130, quarter-wave plate 140, rotating device (not shown), polarizer 160 and light source 170. Glass sample 150 is between polarizer 160 and quarter-wave plate 140.Quarter-wave plate 140 can be turned by rotating device It moves to rotate fixed angle around the axis direction perpendicular to surface.In the present embodiment, which can be electronic horse It reaches, is also possible to cylinder.Polarizer 160, glass sample 150, quarter-wave plate are passed sequentially through by the light that light source 170 issues 140 and analyzer 130.Wherein, polarizer 160 is orthogonal with the polarization axle of analyzer 130.Passed through by the light incidence that light source generates Polariscope 160 generates linearly polarized light.Wherein, light source 170 can be white light source.Pass sequentially through polarizer 160, glass sample 150, Figure line is presented in the light of quarter-wave plate 140 and analyzer 130 on camera lens 120.The detection of glass strain defect can be used Device 110 is imaged the figure line under different angle, obtain the first imaging and second imaging, and then by analysis first at Picture and the gray value of the second imaging are to determine glass sample with the presence or absence of stress defect.Wherein, the detection dress of glass strain defect Setting may include image-forming module, and in the present embodiment, which can be camera, specifically can be line-scan digital camera or face Array camera etc..

The detection method of glass strain defect provided by the embodiments of the present application can also be applied to following application environment, with Application environment shown in FIG. 1 the difference is that: optical axis direction can be used symmetrical two four relative to angular bisector direction / mono- wave plate replaces making quarter-wave plate rotate fixed angle using rotating device in Fig. 1, then respectively at two four It is imaged respectively above/mono- wave plate using two camera lenses and two image-forming modules, obtains the first imaging and the second imaging, it is right Processing method after imaging is similar with above-described embodiment, no longer writes herein.

The embodiment of the present application provides a kind of detection method of glass strain defect, as shown in Fig. 2, this method may include Following steps:

Step S210 makes linearly polarized light pass sequentially through glass sample, quarter-wave plate and analyzer, wherein linearly polarized light Polarization direction it is orthogonal with the polarization axle of analyzer.

If there are stress defect in glass sample, linearly polarized light can generate birefringent, shape under the action of stress At two light beams that beam polarization direction is orthogonal and the direction of propagation is different, the two-beam by quarter-wave plate and analyzer it After interfere, formed stress line.

Step S220 acquires the first imaging of glass sample when the optical axis of quarter-wave plate is in first angle, the One angle is that the optical axis of quarter-wave plate is flat relative to the polarization direction of linearly polarized light and 45 degree of angles of the polarization axle of analyzer The angle of separated time.

Step S230 acquires the second imaging of glass sample when the optical axis of quarter-wave plate is in second angle, the Two angles are opposite with the equal in magnitude of first angle, symbol.

In step S220 and S230, in imaging process twice, quarter-wave plate is respectively relative to 45 degree of angle bisections Line is at first angle and second angle, and first angle and second angle are equal in magnitude, symbol is opposite (i.e. respectively along clockwise direction And counterclockwise), therefore the stress line as caused by glass sample stress is complete for light and shade in the first imaging and the second imaging It is corresponding；And similar sum of the grayscale values pattern is presented in the first imaging and the second imaging in the other defect unrelated with stress.Wherein, The size θ of first angle and second angle depends on the other parameters of stress intensity and glass on glass sample, specifically may be used To be set according to the actual situation.In one embodiment, θ is specifically as follows 3 ° -10 °.In one embodiment, θ is 3 °. In one embodiment, θ is 5 °.In another embodiment, θ is 8 °.In yet another embodiment, θ is 10 °.

Step S240 obtains the gray value of the first imaging and the gray value of the second imaging.

Step S250 determines that glass sample whether there is according to the gray value of the gray value of the first imaging and the second imaging and answers Power defect.

In the present embodiment, can to imaging carry out gray value calculating, with quantificational expression be imaged in pixel light and shade it is poor Not.The stress line due to caused by glass sample stress is completely corresponding for light and shade in the first imaging and the second imaging, and and stress Similar sum of the grayscale values pattern is presented in the first imaging and the second imaging in unrelated other defect, therefore can be according to the first one-tenth The gray value of picture and the gray value of the second imaging determine glass sample with the presence or absence of stress defect.

The detection method of above-mentioned glass strain defect, by the polarization for being respectively relative to linearly polarized light in quarter-wave plate When the angular bisector of the polarization axle of direction and analyzer is at first angle and second angle, acquire glass sample first imaging and Second imaging, and stress defect is determined according to the gray value of the first imaging and the second imaging, it can reduce and even be eliminated sample table Face flaw or dust interference, detect glass strain defect, and reproducible fast and reliablely, are able to carry out the inspection of typical products in mass production It surveys.

In one embodiment, as shown in figure 3, step S250 includes:

Step S251, according to first imaging gray value with second imaging gray value to first imaging and second be imaged into Row filtration treatment and noise reduction process include defect abnormal area in third imaging to generate third imaging.

In addition to the defect area as caused by stress further includes being lacked by unrelated with stress in the first imaging and the second imaging It falls into region (for example, defect as caused by glass surface flaw or dust).In order to more reliably determine stress defect, need to One imaging and the second imaging are filtered processing.In addition, due to the influence of environment and testing conditions, in the first imaging and the second one-tenth There are noise as in, needs to carry out noise reduction process to the first imaging and the second imaging, keep it more smooth.Therefore, by filtering Third imaging after processing and noise reduction process includes defect abnormal area.

Step S252, according to defect abnormal area first imaging in corresponding gray value with second be imaged in corresponding ash Angle value determines whether the defect abnormal area is stress defect area.

After determining defect abnormal area, the stress line due to caused by glass sample stress is in the first imaging and the second one-tenth As in for light and shade is completely corresponding and similar gray scale is presented in the first imaging and second are imaged in the other defect unrelated with stress Value and pattern, therefore can determine that the defect is different according to corresponding gray value of the region in the first imaging and the second imaging Whether normal region is stress defect area.

The detection method of above-mentioned glass strain defect, by according to the gray value of the first imaging and the gray value of the second imaging Processing and noise reduction process are filtered to the first imaging and the second imaging, caused by stress nuisance defects and environment can be filtered The influence of noise and the profile for determining defect abnormal area；Pass through corresponding gray scale in being imaged according to defect abnormal area first Value determines whether the defect abnormal area is stress defect area with corresponding gray value in the second imaging, can reliably determine Glass strain defect.

In one embodiment, as shown in figure 4, step S251 includes:

The gray value of the gray value of first imaging and the second imaging is carried out difference operation, to be filtered by step S2511 Imaging that treated.

In the present embodiment, difference operation can be carried out to the gray value of the first imaging and the second imaging.In this implementation In example, by carrying out difference calculating, the defect similar in gray value in the first imaging and the second imaging can be fallen with primary filtration Interference.In one embodiment, difference operation be by first imaging gray value with second be imaged gray value subtract each other divided by 2 it Result afterwards adds 128.In another embodiment, difference operation is that the gray value of the first imaging is subtracted the second imaging Gray value takes absolute value again.After carrying out above-mentioned operation to the gray value of the first imaging and the second imaging, to be filtered Imaging that treated.

Step S2512 carries out process of convolution to the imaging after filtration treatment, to obtain the imaging after noise reduction process.

In the present embodiment, by carrying out process of convolution to the imaging after filtration treatment, so as to change image pixel intensities, And then influence the intensity of other pixels of surrounding.By using convolution technique create filter, available some image effects, such as It obscures.In the present embodiment, process of convolution is mainly used for filtering out noise, and the imaging after making filtration treatment is more smooth, thus Imaging after obtaining noise reduction process.

Step S2513 carries out binary conversion treatment to the imaging after noise reduction process, to determine defect abnormal area, and generates Third imaging.

In the present embodiment, by binary conversion treatment can be easier obtain imaging in target area geometrical characteristic or Other features of person, such as due to the binaryzation of image is greatly reduced data volume in image, so as to highlight the profile of target. By carrying out binary conversion treatment to the imaging after noise reduction process, the profile of defect abnormal area can be highlighted.Wherein, defect is different Normal region refers to that gray value differs biggish point in the first imaging and the second imaging.In some embodiments, image binaryzation Processing includes picture smooth treatment, is eliminated the noise in the imaging after binaryzation by picture smooth treatment, to obtain the Three imagings.Defect abnormal area is more obvious in third imaging, i.e., defect abnormal area and normal region have more obvious Boundary.

The detection method of above-mentioned glass strain defect, by carrying out difference operation, convolution to the first imaging and the second imaging Processing and binary conversion treatment, can primary filtration fall the dry of in the first imaging and the second imaging defect similar in gray value It disturbs, filter noise and smoothed image and determine the profile of defect abnormal area, so as to more reliably detect stress defect.

In one embodiment, as shown in figure 5, step S252 includes:

Step S2521, by defect abnormal area in the first imaging corresponding ash in the imaging of corresponding sum of the grayscale values second Angle value is compared.

Step S2522 judges that defect abnormal area is corresponding in the corresponding imaging of sum of the grayscale values second in the first imaging Whether the absolute value of the difference between gray value meets preset condition；If meeting preset condition thens follow the steps S2523, otherwise hold Row step S2524.

Step S2523 determines that defect abnormal area is stress defect area.

Step S2524 determines that defect abnormal area is not stress defect area.

In glass strain defects detection, due to the influence of environment and testing conditions, by filtering and the imaging after noise reduction It is middle may also to have the defects that minority is unrelated with stress.In the present embodiment, it in order to more reliably determine stress defect, will lack Falling into abnormal area, corresponding gray value is compared in the corresponding imaging of sum of the grayscale values second in the first imaging.If defect is different Normal region meets in the absolute value of the difference in the imaging of sum of the grayscale values second corresponding in the first imaging between corresponding gray value Preset condition then determines defect abnormal area for stress defect area；Otherwise determine that defect abnormal area is not stress defect area Domain.It may include multiple defect abnormal areas in third imaging, then need to sentence each of multiple regions region It is fixed, to determine whether the region is stress defect area.In addition, then may be used due to including many pixels in each defect area The gray value of multiple pixels in the region is sampled.Then the gray value of the pixel wherein sampled is successively carried out Determine, if meeting preset condition, stops the judgement to later pixel point and determine that the region is stress defect area；If All pixels point is still unsatisfactory for preset condition after being all determined in one defect area, then determining the region not is that stress lacks Fall into region.

Here preset condition specifically can according to glass sample answer force request and it is different.For holding to stress The low application of bearing property, when the absolute value of the difference of gray value of less o'clock in the region in the first imaging and the second imaging is greater than When preset value, then it can be determined that the region is stress defect area.For the application high to stress tolerance；When in the region When absolute value of the difference compared with gray value of the multiple spot in the first imaging and the second imaging is greater than preset value, just determine that the region is to answer Power defect area.Therefore, in one embodiment, as long as preset condition can be a pixel in a defect area When the absolute value of the difference of gray value in the first imaging and the second imaging is greater than preset value, then determine the region for stress defect Region.Preset condition can be the gray value for having 5 pixels in a defect area in the first imaging and the second imaging Absolute value of the difference be greater than preset value when, then determine the region for stress defect area.Preset value is similarly dependent on to hyaloid Product answer force request.In one embodiment, preset value can be 100.In another embodiment, predetermined threshold can be 90.In yet another embodiment, predetermined threshold can be 80.Specifically can flexibly it determine according to the actual situation.

The detection method of above-mentioned glass strain defect passes through corresponding gray value during defect abnormal area is imaged first It is compared with corresponding gray value in the second imaging, and it is default to determine whether the absolute value of the difference of the gray value in the two meets Condition can determine whether defect abnormal area is stress defect according to concrete application.

Fig. 6 A-6C shows the first imaging, the second imaging and processing of the glass sample obtained according to the detection method of Fig. 5 The third imaging obtained afterwards.It can be seen that including defect exceptions area in the first imaging in Fig. 6 A and the second imaging in Fig. 6 B Domain.In order to determine whether the defect abnormal area is stress defect area, using the method in Fig. 5 to the first imaging and the second one-tenth As being handled.The third imaging obtained by processing shows the profile of defect abnormal area, by defect abnormal area the Corresponding gray value is compared in the corresponding imaging of sum of the grayscale values second in one imaging: if defect abnormal area is in the first imaging In the absolute value of difference in the imaging of corresponding sum of the grayscale values second between corresponding gray value meet preset condition, then determine to lack Falling into abnormal area is stress defect area；Otherwise determine that defect abnormal area is not stress defect area.As shown in Figure 6 C, pass through The above processing, obtains stress defect area, as shown in the wire in Fig. 6 C, and can be seen that stress line in Fig. 6 A and Fig. 6 B It is that light and shade is corresponding.

The embodiment of the present application also provides a kind of detection devices of glass strain defect, as shown in fig. 7, device 700 makes line Polarised light passes sequentially through glass sample, quarter-wave plate and analyzer, wherein the polarization direction of linearly polarized light and analyzer Polarization axle is orthogonal；Device 700 includes:

First imaging acquisition module 710, for acquiring hyaloid when the optical axis of quarter-wave plate is in first angle Product first imaging, first angle be quarter-wave plate optical axis relative to linearly polarized light polarization direction and analyzer it is inclined The angle of 45 degree of angular bisectors of vibration axis；

Second imaging acquisition module 720, for acquiring hyaloid when the optical axis of quarter-wave plate is in second angle Second imaging of product, second angle are opposite with the equal in magnitude of first angle, symbol；

Gray value obtains module 730, for obtaining the gray value of the first imaging and the gray value of the second imaging；

Stress determining defects module 740, for determining glass according to the gray value of the first imaging and the gray value of the second imaging It whether there is stress defect on glass sample.

In one of them embodiment, as shown in figure 8, stress determining defects module 740 includes:

Generation unit 741 is imaged in third, and the gray value for being imaged according to the gray value of the first imaging and second is to first Imaging is filtered processing and noise reduction process with the second imaging, includes defect exceptions area in third imaging to generate third imaging Domain；

Judging unit 742, in corresponding gray value and the second imaging in being imaged according to defect abnormal area first Corresponding gray value determines whether defect abnormal area is stress defect area.

In one of them embodiment, third imaging generation unit 741 is specifically used for:

By first imaging gray value with second imaging gray value carry out difference operation, with obtain filter treated at Picture；

Process of convolution is carried out to the imaging after filtration treatment, to obtain the imaging after noise reduction process；

Binary conversion treatment is carried out to the imaging after noise reduction process, to determine defect abnormal area, and generates third imaging.

In one of them embodiment, judging unit 742 is specifically used for:

By defect abnormal area, corresponding gray value compares in the corresponding imaging of sum of the grayscale values second in the first imaging Compared with；

If defect abnormal area is in corresponding sum of the grayscale values second in the first imaging is imaged between corresponding gray value The absolute value of difference meets preset condition, then determines defect abnormal area for stress defect area；Otherwise determine defect exceptions area Domain is not stress defect area.

In one of them embodiment, the light incidence that linearly polarized light is issued by white light source is generated by polarizer, The polarization axle of polarizer and the polarization axle of analyzer are orthogonal.

Using according to the above method of the present invention and device, can reduce the dust for even being eliminated sample surfaces interference, fastly Speed reliably detects glass strain defect, and reproducible, is able to carry out the detection of typical products in mass production.

Only several embodiments of the present invention are expressed for above embodiments, and the description thereof is more specific and detailed, but can not Therefore it is construed as limiting the scope of the patent.It should be pointed out that for those of ordinary skill in the art, In Under the premise of not departing from present inventive concept, various modifications and improvements can be made, and these are all within the scope of protection of the present invention. Therefore, the scope of protection of the patent of the invention shall be subject to the appended claims.