WO2018050114A1

WO2018050114A1 - Glass surface stress detection device

Info

Publication number: WO2018050114A1
Application number: PCT/CN2017/102101
Authority: WO
Inventors: 李俊峰
Original assignee: 北京杰福科技有限公司; 南通杰福光学仪器科技有限公司
Priority date: 2016-09-18
Filing date: 2017-09-18
Publication date: 2018-03-22

Abstract

A glass surface stress detection device comprises an illuminating unit (10), a detection prism (20), and an imaging unit (30). The illuminating unit (10) is used for providing polarized illuminating light, and comprises a light source. The detection prism (20) comprises a detection surface (20a) used for fitting the surface of detected glass for detection. The imaging unit (30) comprises a quartz wedge (32), an analyzer plate (33), and a lens group (34) that are sequentially disposed along a light path. The illuminating unit (10) also comprises a cylindrical mirror (15). The cylindrical mirror (15) is disposed between the light source and the detection prism (20), and has positive radial refractive power, and the cylindrical mirror (15) is arranged to allow the axial direction of the disposed cylindrical mirror (15) to be perpendicular to a common light path normal plane where normals of at least part of the light and a detection surface (20a) are located. The illuminating light is converged by the cylindrical mirror (15), incident light on the detection surface (20a) of the detection prism (20) comprises different incidence angles of critical angles of total reflection, and accordingly manual work on incidence angle adjustment can be alleviated or omitted, and the glass surface stress detection device has a more compact integral structure.

Description

Glass surface stress detecting device

Technical field

The present disclosure relates to an optical detecting device, and in particular to a glass surface stress detecting device.

Background technique

Glass sheets are common materials in everyday life and industrial production. In order to measure the quality of the glass sheet and ensure the safety of the glass sheet, it is often necessary to measure the stress in the glass sheet. In order to detect the stress of the glass plate, it is stipulated in the national standard and the like that the surface stress of the glass is measured by means of birefringence to characterize the stress level inside the glass. At present, in actual use, the methods for measuring the surface stress of the glass mainly include: differential surface refractometry (DSR), surface grazing angle (GLAS), and recently introduced a method of transmitting laser light in Estonia. Among them, the GASP method has high measurement accuracy for tempered glass with low surface stress, and is suitable for surface stress detection of semi-tempered glass used in construction.

The measurement principle of GASP is: the incident polarized beam enters the thin layer of the glass surface, and runs away from the glass after running a distance from the parallel glass surface. Due to the surface stress of the glass, the beam produces birefringence, and the optical path difference can be accurately measured by the quartz wedge. Quartz wedges are available in a variety of precision grades, so GASP can be accurately measured regardless of stress.

However, the existing GASP-type glass surface stress detecting device needs to adjust the angle of incident light and the two degrees of freedom of the incident point during the measurement process, and the position and angle of the mirror need to be adjusted after the exit, and many components are manually adjusted. It is cumbersome, inefficient, unable to work under strong light, has low adaptability, and is bulky and inconvenient to carry.

Summary of the invention

In view of the above-mentioned defects or deficiencies existing in the prior art, the present invention provides a portable glass surface stress detecting device which is simple in structure and easy to operate.

According to an embodiment of the present invention, there is provided a glass surface stress detecting apparatus comprising: an illumination unit for providing polarized illumination light, the illumination unit comprising a light source; and a detection prism having a surface for attaching to the surface of the glass to be inspected a detection surface that is combined for detection, at least part of the light from the illumination unit being incident on the detection surface of the detection prism at a critical angle of total reflection, and from the detection surface after being propagated along the surface of the glass to be inspected The surface of the detected glass is coupled and derived; and an imaging unit comprising a quartz wedge, a polarizing plate and a lens group disposed in sequence along the optical path, the imaging unit being arranged to receive light from the detecting prism and form a detection image, wherein The illumination unit further includes a cylindrical mirror disposed between the light source and the detecting prism, having a positive radial refractive power, and the cylindrical mirror being disposed such that its axial direction is perpendicular to the at least a portion The normal plane of the optical path where the light is co-located with the normal of the detection surface.

Preferably, the light source may comprise a laser and a collimating beam expanding mirror that enlarges the diameter of the beam from the laser.

Preferably, the light source may further comprise a refractive system disposed between the laser and the collimating beam expander, the refractive system folding the optical path between the laser and the collimating beam expander by 180 degrees.

Preferably, the lighting unit may further include a polarizer disposed along the optical path behind the cylindrical mirror.

Preferably, the illumination unit may further include an aperture disposed between the light source and the detecting prism along the optical path for blocking at least a portion of the incident light incident on the detecting surface to be less than a critical angle of the total reflection Light. More preferably, the aperture is positionally adjustable in a direction perpendicular to the optical path.

The detection prism may also include a reflective surface that reflects light entering the detection prism and directs it to the detection surface.

The imaging unit may further include a mirror disposed between the detecting prism and the quartz wedge and an adjusting device for adjusting the position and posture of the mirror.

Preferably, the glass surface stress detecting device may further include a light shielding cover, the illumination unit, the detection prism, and the imaging unit being housed in the light shielding cover, and the light shielding cover is formed with a detection hole, and the detection surface of the detection prism is The detection hole is exposed.

Preferably, the glass surface stress detecting device may further include an image detecting unit, and the detecting An image formed by the imaging unit is measured.

Preferably, the glass surface stress detecting device may further include: a data processing unit disposed in the light shielding cover, the image detecting unit is electrically connected to the data processing unit; and formed on a surface of the light shielding cover or supported a display unit on the light shielding cover, the display unit being electrically connected to the data processing unit for displaying the detection image.

In the present invention, the illumination light is concentrated by adding a cylindrical mirror so that the light incident on the detection surface of the detection prism has different incident angles, including the critical angle, so that the artificial adjustment of the incident angle can be alleviated or even eliminated. jobs. Accordingly, the member for adjusting the incident angle can be omitted in this way, so that the overall structure of the glass surface stress detecting device is made more compact.

DRAWINGS

Other features, objects, and advantages of the invention will be apparent from the description of the appended claims.

1 is a schematic structural view of a glass surface stress detecting device according to Embodiment 1 of the present invention;

2 is a schematic structural view of a glass surface stress detecting device according to Embodiment 2 of the present invention;

3 is a schematic structural view of a glass surface stress detecting device according to Embodiment 3 of the present invention;

4 is a schematic structural view of a glass surface stress detecting device according to Embodiment 4 of the present invention.

detailed description

The present application will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention, rather than the invention. It should also be noted that, for the convenience of description, only parts related to the invention are shown in the drawings.

1 is a view showing the structure of a glass surface stress detecting device 100 according to Embodiment 1 of the present invention. schematic diagram. As shown in FIG. 1, the glass surface stress detecting device 100 includes an illumination unit 10, a detecting prism 20, and an imaging unit 30.

The illumination unit 10 is for providing polarized illumination light. The lighting unit includes a light source. The illumination unit 10 further comprises a cylindrical mirror 15 disposed between the light source and the detection prism 20, the cylindrical mirror 15 being arranged such that its axial direction is perpendicular to the normal plane of the optical path. Here, the normal plane of the optical path refers to the plane where the incident ray and the normal line lie together.

The detecting prism 20 has a detecting surface 20a for adhering to the surface of the glass to be detected for detection, and at least part of the light from the lighting unit 10 is incident on the detecting surface 20a at a critical angle of total reflection, and is The detection surface is coupled out of the detected glass surface 20a by the detection surface after propagation.

The imaging unit 30 includes a quartz wedge 32, a polarizing plate 33, and a lens group 34 which are sequentially disposed along the optical path. The imaging unit 30 is arranged to receive light from the detection prism 20 and form a detection image.

In the illustrated example, the beam from the source passes through the cylindrical mirror 15 to produce a converging fan-shaped converging beam that is directed onto the detection surface of the detection prism 20. The fan-shaped converging beams have different angles of incidence when entering the detecting prism 20, and these incident angles include a total reflection critical angle. Therefore, the fan-shaped converging beam is generated by the cylindrical mirror so that at least part of the light incident on the detecting surface 20a of the detecting prism 20 has a total reflection critical angle, which can be used to detect the glass surface stress by the GASP method. Compared with the glass surface stress detecting device of the prior art, the glass surface stress detecting device according to the embodiment of the present invention can alleviate or even eliminate the work of adjusting the incident angle when the light is incident on the detecting surface 20a; accordingly, the structure of the device is also made It is simpler and more compact.

In the example shown in FIG. 1, the light source in the illumination unit 10 includes a laser 12 and a collimating beam expander 13. The laser emitted by the laser 12 has good monochromaticity, good coherence, good directivity and high brightness. The collimator beam expander 13 is used to enlarge the diameter of the beam from the laser 12 such that the beam entering the cylindrical mirror 15 is a collimated beam.

However, the present invention is not limited thereto in this respect; in the glass surface stress detecting device according to the present invention, the light source may take other suitable forms. For example, the light source can include a single color LED and is not limited to the use of a collimating beam expander.

The lighting unit 10 may further include a polarizer 16 for selecting light of a certain polarization direction The detecting prism 20 is irradiated. The certain polarization direction is, for example, a direction approximately 45 degrees from the normal plane of the optical path, but is not limited thereto. The polarizer 16 can be disposed at any suitable location in the optical path prior to detecting the prism, such as between the cylindrical mirror 15 and the detection prism 20 as shown in FIG. Where the light source comprises a laser, the polarizer 16 may or may not be used.

The detecting prism 20 may be a triangular prism, a rectangular prism whose incident surface is a circular arc shape, or the like. The detecting prism 20 shown in Fig. 1 is a square prism. The detecting prism 20 has a detecting surface 20a for bonding to the surface of the glass to be inspected. The detecting prism 20 further includes a reflecting surface 20b that reflects the light entering the detecting prism 20 and guides it to the detecting surface.

The detecting prism 20 may include an introduction prism 21 and a lead-out prism 22, which may be separated by a metal spacer or a diaphragm.

A fan-shaped converging beam from the cylindrical mirror 15 enters the detecting prism 20 and is irradiated onto the detecting surface 20a at different incident angles, wherein at least part of the light having a critical angle of total reflection enters the surface of the glass to be inspected and propagates a distance along the surface of the glass. The detected surface 20a is coupled out. Due to the surface stress of the glass, the light beam is birefringent, and therefore, the light derived from the detecting surface 20a contains an optical path difference in one direction.

The derived light is emitted to the lens group 34 after passing through the quartz wedge 32 and passing through the polarizing plate 33. The use of the quartz wedge 32 allows the light to produce an optical path difference in another different direction which is superimposed with the optical path difference due to birefringence, causing the light to interfere to produce oblique interference fringes. The glass surface stress value is proportional to the tilt angle tangent function of the interference fringes. By measuring the tilt angle of the interference fringes, the glass surface stress value can be calculated.

The imaging unit 30 may further include a mirror 31 disposed between the detecting prism 20 and the quartz wedge 32 and an adjusting device (not shown) for adjusting the position and posture of the mirror 31. A mirror 31 is placed between the detecting prism 20 and the quartz wedge 32 and adjacent to the detecting prism 20 to reflect the light emitted from the detecting prism 20 into the quartz wedge 32. The position of the mirror 31 adjacent to the detecting prism 20 can be adjusted by the user via the adjusting means to adjust the angle of the light entering the lens group 34. The adjustment device can be a wire assembly to improve ease of use and adjustment accuracy.

The glass surface stress detecting device 100 according to an embodiment of the present invention may further include an image detecting unit 35 that detects an image formed by the imaging unit 30. Image detecting unit 35 It may be a charge coupled device (CCD) camera, and a light of a critical angle incident from the detecting prism 20 passes through the lens group 34 and is imaged onto the CCD camera 35. As a new type of photodetector, CCD camera has the ability to store and transfer information charges, and can directly complete the acquisition, conversion, storage and output of spatial information.

In addition, the glass surface stress detecting device 100 may further include a cover 40. The cover is preferably a light-shielding cover. The light shielding cover 40 houses the above-described illumination unit 10, detection prism 20, imaging unit 30, and the like for shielding stray light from the outside.

2 is a schematic structural view of a glass surface stress detecting device according to Embodiment 2 of the present invention. The structure in this embodiment is substantially the same as that of the foregoing embodiment 1, that is, the detecting prism 20 and the imaging system 30 employ the same elements and structures, except that in the illumination system 10' of the glass surface stress detecting device 100', Between the laser 12 and the beam expander 13, a refractive system 14 is provided which folds the optical path between the laser 12 and the beam expander 13 by 180°.

Generally, the laser 12 is relatively bulky, for example, having a height dimension of up to about 7-8 cm. If the central axis of the laser 12 is aligned directly above the collimator beam expander 13 with the central axis of the collimator beam expander 13, the overall height dimension of the glass surface stress detecting device 100' may be large. By folding the optical path between the laser 12 and the collimating beam expander 13 by 180 degrees using the refractive system 14, the height dimension of the device 100' can be significantly reduced. As shown in FIG. 2, the refractive system 14 can include a plurality of mirrors. Alternatively, the refractive system 14 can also include at least one prism.

Figure 3 is a schematic view showing the structure of a glass surface stress detecting device according to Embodiment 3 of the present invention. The structure in this embodiment is basically the same as that of the foregoing embodiment 1, except that the illumination unit 10 of the glass surface stress detecting device 100" further includes a diaphragm 17 disposed between the light source 11 and the detecting prism 20 along the optical path. To limit the range of light incident between the detection surface incident on the detection prism 20 and the surface of the glass to be inspected, particularly to block at least a portion of the light incident on the detection surface that is less than the total reflection critical angle.

Specifically, a part of the light emitted from the illumination unit 10 having an incident angle smaller than the critical angle of the total reflection angle enters the glass to be detected and is reflected back, and enters the detecting prism 20 again to become an interference light. The function of the aperture 17 is to block this portion of the incident light that may interfere with the light before it is incident on the detecting prism 20. Further, the aperture 17 is along a side perpendicular to the optical path The orientation is adjustable for different applications, especially where the critical angle of total reflection is different due to the different refractive indices of the glass being tested. As shown in FIG. 2, the aperture 17 can be placed between the light source 11 and the cylindrical mirror 15. The position of the diaphragm 17 in the figure is for illustration only, and the present invention is not limited thereto. For example, the aperture 17 can also be placed between the cylindrical mirror 15 and the detection prism 20. If the illumination unit 10 includes the polarizer 16, the aperture 17 can also be arranged between the cylindrical mirror 15 and the polarizer 16 or biased. Between the device 16 and the detecting prism 20.

4 is a schematic structural view of a glass surface stress detecting device according to Embodiment 4 of the present invention. As shown in FIG. 4, a detection hole (not shown) may be formed in the light shielding cover 40, and the detection surface 20a of the detection prism 20 is exposed from the detection hole.

In order to enable the user to intuitively understand the detection result, the glass surface stress detecting device may further include: a data processing unit (not shown) disposed in the light shielding housing 40, and the image detecting unit 35 is electrically connected to the data processing unit; The display unit 90 is formed on the surface of the light-shielding cover 40 or supported on the light-shielding cover 40 as shown in FIG. The display unit 90 may include a graphical image interface that displays the detection results, and controls a small data processing unit built into the light shielding housing 40 to perform physical or virtual keys such as initialization, clearing, calibration, fault detection, and the like. Display unit 90 can be a touch display. Further, the display unit 90 is further integrated with a computing module for performing at least part of the data processing task.

It should be understood that the glass surface stress detecting device of the present invention is not limited to the specific function or configuration of the imaging unit described above. In particular, although the imaging unit includes a lens group in the above first embodiment and its modifications, the glass surface stress detecting device according to the present invention may have any other suitable form of imaging unit. For example, the imaging unit may be simply implemented as a visual observation system for directly observing interference fringes generated by totally reflected light by the naked eye, may not include mirrors or include more or fewer mirrors, and the like.

The above description is only a preferred embodiment of the present application and a description of the principles of the applied technology. It should be understood by those skilled in the art that the scope of the invention referred to in the present application is not limited to the specific combination of the above technical features, and should also be covered by the above technical features without departing from the inventive concept. Other technical solutions formed by any combination of their equivalent features. For example, the above features are combined with the technical features disclosed in the present application, but are not limited to the technical features having similar functions.

Claims

A glass surface stress detecting device comprising:

a lighting unit for providing polarized illumination light, the illumination unit comprising a light source;

a detection prism having a detection surface for conforming to a surface of the glass to be inspected for detection, at least part of the light from the illumination unit being incident on the detection surface of the detection prism at a critical angle of total reflection, and Coupling from the surface of the detected glass by the detection surface after propagation along the surface of the glass being inspected; and

An imaging unit including a quartz wedge, a polarizing plate, and a lens group disposed in sequence along an optical path, the imaging unit being arranged to receive light from the detecting prism and form a detected image,

Wherein the illumination unit further includes a cylindrical mirror disposed between the light source and the detecting prism, having a positive radial refractive power, and the cylindrical mirror being disposed such that its axial direction is perpendicular to the At least a portion of the light is in a plane normal to the optical path where the normal to the detection surface is.
The glass surface stress detecting apparatus according to claim 1, wherein said light source comprises a laser and a collimating beam expanding mirror that expands a diameter of a light beam from said laser.
The glass surface stress detecting apparatus according to claim 2, wherein said light source further comprises a refractive system disposed between said laser and said collimating beam expanding mirror, said refractive system and laser collimating beam expander The light path between them is folded 180 degrees.
The glass surface stress detecting device according to claim 1, wherein said illumination unit further comprises a polarizer disposed along the optical path behind said cylindrical mirror.
The glass surface stress detecting apparatus according to claim 1, wherein said illumination unit further comprises a stop disposed between said light source and said detecting prism along an optical path for blocking light incident on said detecting surface The medium incident angle is less than at least a portion of the light of the total reflection critical angle.
The glass surface stress detecting apparatus according to claim 5, wherein said aperture is positionally adjustable in a direction perpendicular to the optical path.
The glass surface stress detecting device according to claim 1, wherein said detecting prism further comprises reflecting and guiding light entering the detecting prism to said detecting surface Reflective surface.
The glass surface stress detecting device according to claim 1, wherein said imaging unit further comprises a mirror disposed between said detecting prism and said quartz wedge, and an adjusting device for adjusting a position and a posture of said mirror .
The glass surface stress detecting apparatus according to any one of claims 1 to 8, further comprising a light shielding cover, the illumination unit, the detecting prism, and the image forming unit being housed in the light shielding housing, and the light shielding housing is formed with a detection hole The detecting surface of the detecting prism is exposed from the detecting hole.
The glass surface stress detecting apparatus according to claim 9, further comprising an image detecting unit that detects an image formed by said imaging unit.
The glass surface stress detecting device according to claim 10, wherein the glass surface stress detecting device further comprises:

a data processing unit disposed within the light shielding housing, the image detecting unit being electrically connected to the data processing unit; and

a display unit formed on a surface of the light shielding cover or supported on the light shielding cover, the display unit being electrically connected to the data processing unit for displaying the detection image.