CN204535899U - Glass surface stress detection device - Google Patents

Abstract

The utility model relates to a detection device for detecting the surface stress of glass, which includes a light-shielding outer cover, an illumination unit inside the outer cover, a detection prism and an imaging unit. The light from the illumination unit entering the detection prism can be totally reflected on the contact surface, so that the stress level of the glass can be characterized by using the birefringence caused by the total reflection of the light on the glass surface. Recorded by electrophotographic equipment, miniaturized and digitized high-precision measurement has been realized.

Description

Glass surface stress detection device

technical field

The utility model relates to an optical detection device, in particular to a detection device for detecting the surface stress of glass.

Background technique

Glass is a common material in daily life and industrial production. For example, tempered glass is a kind of well-known safety glass, which is widely used in construction, automobile, glass curtain wall, household glass products and other fields. For tempered glass, in order to increase the strength of the glass, chemical or physical methods are usually used in the production process to form a certain amount of compressive stress on the glass surface. When the glass is subjected to external forces, the surface stress is first offset, thereby improving the bearing capacity. For ordinary glass, due to the influence of various processes in the processing process, there will be residual stress in the glass plate. If the stress exceeds a certain range, it will cause obvious loss to the performance of the glass and constitute a defect. Therefore, the stress level is usually a measure of glass. An important indicator of glass plate quality, involving the use of glass plate safety.

In order to obtain this indicator, the national standard and other standards stipulate 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, there are two methods for measuring the surface stress of glass: differential surface refraction method DSR (Differential Surface Refractometry) and surface grazing angle polarization method GASP (Grazing Angle Surface Polarimetry). Among them, the DSR method is widely used by various testing institutions because it uses less optical parts and the price of testing instruments is relatively low. The existing DSR type glass surface stress detector is relatively bulky, and most of them rely on manual measurement of the stress through the micrometer eyepiece, and then calculate the stress value according to the formula. This method is obviously limited by the measurement accuracy of the naked eye, and is not conducive to Electronic data processing.

Utility model content

The utility model provides a glass surface stress detection device, which obtains the double refraction light returned from the glass surface to be tested by providing a small-sized optical system in the shading cover, and cooperates with an image capture device for electrophotography to obtain high-precision detection results , to avoid the influence of stray light.

According to a kind of glass surface stress detection device of the present utility model, comprise light-shielding outer cover, lighting unit, detection prism and imaging unit, described lighting unit, detection prism and imaging unit are all located inside light-shielding outer cover; Wherein, described light-shielding outer cover is used for Shield the influence of external stray light on the detection and define the external dimensions of the detection device; the detection prism is in contact with the surface of the detected glass through the refraction liquid, so that the light entering the detection prism from the illumination unit can be totally reflected on the contact surface , so that the information containing the birefringence ability of the glass is introduced into the totally reflected light, which enters the imaging unit for imaging; the imaging unit includes at least two mirrors, and the position of one of the at least two mirrors can be determined by using to adjust.

Further, the lighting unit includes an LED light source and an optical filter placed on the light path behind the light source for filtering the light emitted by the light source.

Preferably, the detection prism is a square prism, and the way to adjust the position of the first reflector is screw adjustment.

Specifically, the imaging unit sequentially includes a first reflector, a lens group, a second reflector, an analysis mirror and a photosensitive element along the optical path direction; the first reflector is a reflector whose position can be adjusted by a user. The photosensitive element is one of CCD, CMOS or PMT, and the analysis mirror is spliced with two polarizers perpendicular to each other or one or more polarization beam splitters are used.

The imaging unit may further include a third reflective mirror, which is located behind the second reflective mirror along the optical path direction and is opposite to the reflective surface of the second reflective mirror.

The third reflection mirror is rotatable, and the analysis mirror is positioned between the second reflection mirror and the third reflection mirror, and the imaging unit further includes a visual observation unit, and the visual observation unit is opposite to the photosensitive element conjugate to the third mirror.

The photosensitive element is electrically connected with the data processing unit, and the data processing unit is a small data processor placed in a light-shielding housing, and the light-shielding housing has a display unit for displaying a graphic image interface including at least the detection results.

According to the glass shard detection device of the present invention, due to the use of a light-shielding cover, the influence of stray light during detection is avoided, and the space occupied by the overall optical path is shortened by using the reflector for multiple reflections, and the use of only one reflector is adjusted to reduce the It reduces the difficulty of use, realizes the miniaturization of the detection device, and improves the detection quality.

Description of drawings

Fig. 1 is a schematic diagram of a glass surface stress detection device according to the present invention.

Fig. 2 is a schematic diagram of the image on the photosensitive element in the glass surface stress detection device according to the present invention.

Fig. 3 is a schematic diagram of the display unit in the glass surface stress detection device according to the present invention.

Fig. 4 is a schematic diagram of another embodiment of the glass surface stress detection device according to the present invention.

Detailed ways

Hereinafter, embodiments of the present utility model will be described in detail with reference to the accompanying drawings. In the following description, for the convenience of understanding and description, the same components are given the same numerals.

Fig. 1 is a schematic diagram of a glass surface stress detection device according to the present invention. As shown in Figure 1, the glass surface stress detection device 100 of the present utility model includes a light-shielding outer cover 1, an illumination unit 2, a detection prism 3 and an imaging unit 4, and the light-shielding outer cover is used to shield the influence of external stray light on the detection and to define the detection device The external dimensions of the illumination source, the detection prism and the imaging unit are all located inside the shading cover, wherein the detection prism is in contact with the surface of the detected glass 5 through the refraction liquid, so that the light injected into the detection prism by the illumination source can pass between the detection prism and the detected glass. The total reflection on the contact surface of the glass is detected, so that the information including the birefringence ability of the glass is introduced into the total reflection light, and then enters the imaging unit for imaging.

Considering the convenience of energy saving and supply voltage, the light source 21 used by the lighting unit is preferably an LED light source, and a filter such as an interference filter 22 is used near the light outlet of the light source or near the light path to purify the light emitted by the light source. Then enter the detection prism 3, in order to reduce the overall volume of the device, reflectors 23 are arranged between the detection prisms of the light source 21. The detection prism 3 may be a triangular prism, a rectangular prism with an arc-shaped incident surface, etc. Preferably, the detection prism 3 is a square prism. Because the light emitted by the light source is filtered, the light incident on the detection prism becomes a light source with good monochromaticity, which reduces the adverse effect of the spectral width of the light source on the measurement after the detection light exits from the glass-prism interface. The incident angle of the light source is determined by scientific calculation, and the use of square prisms with corresponding parameters prevents the operator from choosing among multiple steps and affecting the measurement accuracy.

The imaging unit includes a lens group 41, an analysis mirror 42, and a photosensitive element 43 arranged in sequence according to the optical path. Further, the imaging unit also includes at least two mirrors. As shown in FIG. 1, the imaging unit includes a first mirror a, a second Mirror b and the third mirror c, wherein the first mirror a is placed between the detection prism 3 and the lens group 41, and is adjacent to the detection prism, so as to reflect the light emitted from the detection prism 3 into the lens group 41; The reflective surfaces of mirror b and third mirror c are oppositely arranged, and both are placed between lens group 41 and analysis mirror 42, so as to guide the light focused by lens group 41 to analysis mirror 42, and then enter into The photosensitive element 43 such as CCD/CMOS/PMT forms an image, and a step difference image such as that shown in FIG. 2 appears on the photosensitive element. Further, the position of the first reflector adjacent to the detection prism can be adjusted by the user, thereby adjusting the angle of light entering the lens group 41, so that the light at a critical angle passes through the lens group and then irradiates on the photosensitive element, presenting high-quality For the step difference image, the adjustment method is preferably screw d adjustment, so as to improve the ease of use and the accuracy of adjustment. The analysis mirror 42 can be implemented by splicing two polarizers perpendicular to each other or by using one or more polarization beam splitters.

A data processing unit (not shown) electrically connected to the photosensitive element 43 processes the image of the step difference to obtain the surface stress of the glass. The data processing unit can be realized by a general-purpose computer with data processing software, or use a dedicated small-scale data processor to realize, for example, single-chip microcomputer, FPGA, CPLD etc., the small-scale data processor can be integrated in the photosensitive element 43, at this moment in order to be able to Intuitively allowing users to understand the detection results, a display unit 44 is provided on or protruding from the surface of the light-shielding outer cover. As shown in Figure 3, the display unit 44 can include a graphical image interface for displaying the test results, and control the small data processor built in the test device to perform physical or virtual keys such as initialization, clearing, calibration, fault detection, etc., corresponding , the display unit may be a touch display screen.

Optionally, the third reflector c may be omitted, or the third reflector c is a rotatable reflector. When the third reflector is a rotatable reflector, as shown in FIG. 4 , the imaging device further includes a visual observation unit 45. At this time, the analysis mirror 42 is located between the second reflector b and the third reflector c. On the optical path between the visual observation unit 45 and the photosensitive unit 43 relative to the third reflector c, the user can choose to rotate the third reflector c out of the optical path, so as to observe with the visual observation unit 45 and calculate the result manually. Alternatively, after observation by the visual observation unit 45, the third mirror c is rotated and moved into the optical path, so that the photosensitive element 43 performs image recording to realize electronic measurement, which is similar to the working mode of a DSLR camera. When using a photosensitive element to realize electronic measurement, preferably, a display unit (not shown in Figure 4) with a built-in small data processor and an outer cover as shown in Figure 3

According to the glass surface stress detection device of the embodiment, the shading unit is used to avoid the influence of stray light, and the space occupied by the overall optical path is shortened by using the reflector, and the miniaturization is realized. Further, by removing the first reflector The other components are fixed installed, so as to avoid the adjustment of multiple components from affecting the detection accuracy, and reduce the difficulty of the user's use. High-precision electronic detection.

The utility model is not limited to the above-mentioned embodiments, and the various implementation modes in the specification are only for illustration, and they do not limit the protection scope of the utility model. Various changes and modifications can be made without departing from the scope of the present invention. Any omission, substitution or modification made on the basis of the disclosed embodiments of the present invention within the knowledge of those skilled in the art will fall within the protection scope of the present invention.

Claims (9)

1. A glass surface stress detection device, comprising a light-shielding outer cover, a lighting unit, a detection prism and an imaging unit, and the lighting unit, the detection prism and the imaging unit are all located inside the light-shielding outer cover; wherein, The light-shielding cover is used to shield the impact of external stray light on the detection and to define the external dimensions of the detection device; The detection prism is in contact with the surface of the glass to be detected through the refraction liquid, so that the light incident on the detection prism from the illumination unit can be totally reflected on the contact surface, so that the fully reflected light includes the birefringence ability of the glass. Information, enter the imaging unit for imaging; The imaging unit includes at least two mirrors, and the position of one of the at least two mirrors can be adjusted by a user. 2. The glass surface stress detection device according to claim 1, characterized in that, The lighting unit includes an LED light source, a filter placed on the light path behind the light source for filtering the light emitted by the light source, and a reflector. 3. The glass surface stress detection device according to claim 1, wherein the detection prism is a square prism. 4. The glass surface stress detection device according to claim 1, wherein the imaging unit sequentially includes a first reflector, a lens group, a second reflector, an analysis mirror and a photosensitive element along the optical path direction; The first reflector is a reflector whose position can be adjusted by a user. 5. The glass surface stress detection device according to claim 4, wherein the photosensitive element is one of CCD, CMOS or PMT, and the analysis mirror is spliced by two polarizers perpendicular to each other or adopts one or more polarizers Dichroic prism. 6. The glass surface stress detection device according to claim 4 or 5, wherein the imaging unit further comprises a third reflector, and the third reflector is located behind the second reflector along the direction of the optical path, and It is opposite to the reflective surface of the second reflector. 7. The glass surface stress detection device according to claim 6, wherein the third reflecting mirror is rotatable, and the analyzing mirror is located between the second reflecting mirror and the third reflecting mirror, so The imaging unit further includes a visual observation unit, and the visual observation unit is conjugate to the photosensitive element relative to the third mirror. 8. The glass surface stress detection device according to claim 4 or 7, wherein the photosensitive element is electrically connected to a data processing unit, and the data processing unit is a small data processor placed in a light-shielding outer cover, so A display unit is provided on the surface of the light-shielding cover or on the protruding surface to display a graphic image interface including at least the detection results. 9. The glass surface stress detection device according to claim 4, the mode of adjusting the position of the first reflector is screw adjustment.