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WO2012128184A1 - Dispositif pour mesurer une contrainte de surface de verre et procédé pour mesurer une contrainte de surface de verre - Google Patents

Dispositif pour mesurer une contrainte de surface de verre et procédé pour mesurer une contrainte de surface de verre Download PDF

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Publication number
WO2012128184A1
WO2012128184A1 PCT/JP2012/056745 JP2012056745W WO2012128184A1 WO 2012128184 A1 WO2012128184 A1 WO 2012128184A1 JP 2012056745 W JP2012056745 W JP 2012056745W WO 2012128184 A1 WO2012128184 A1 WO 2012128184A1
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WIPO (PCT)
Prior art keywords
light
glass
tempered glass
surface stress
measuring
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
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PCT/JP2012/056745
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English (en)
Japanese (ja)
Inventor
山本　宏行
満幸 舘村
誠 白鳥
雄一 飯田
一秀 久野
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
AGC Inc
Original Assignee
Asahi Glass Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Asahi Glass Co Ltd filed Critical Asahi Glass Co Ltd
Priority to CN201280013501.2A priority Critical patent/CN103443603B/zh
Priority to JP2013505936A priority patent/JP5892156B2/ja
Publication of WO2012128184A1 publication Critical patent/WO2012128184A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L1/00—Measuring force or stress, in general
    • G01L1/24—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L1/00—Measuring force or stress, in general
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
    • G01L5/0047—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes measuring forces due to residual stresses

Definitions

  • the present invention relates to a glass surface stress measuring apparatus and a glass surface stress measuring method for nondestructively measuring the amount of compressive stress on the surface of an object of tempered glass.
  • a method of forming a compressive stress layer on the glass surface is generally known.
  • Alkali metal ions typically Li ions and Na ions
  • alkali ions typically Na ions or K ions for Li ions.
  • a typical chemical strengthening method is to exchange K ions for Na ions.
  • JP 2011-084456 A JP-A-53-136886
  • the apparatus for measuring CS and DOL in a nondestructive manner emits light propagated through the surface layer of the glass and observes it, it cannot measure the above-described colored glass having a low visible transmittance such as black. The problem was newly confirmed. In this case, it is necessary to perform a strength measurement test with breakage such as bending strength, crack initiation, load, or sample processing for measuring birefringence, or use EPMA (Electron Probe Micro Analyzer) for chemically strengthened glass. There is no method for measuring the amount of compressive stress or strength of glass other than using a very time-consuming method such as measuring the depth of the diffusion layer of potassium, and the accuracy of the measurement data is low and the reliability is poor.
  • An object of this invention is to provide the apparatus and method which measure the surface stress of the colored glass with the low transmittance
  • the present invention provides a light source, a light supply member that causes light from the light source to enter the surface layer of the tempered glass, and a light extraction member that emits light propagated in the surface layer of the tempered glass to the outside of the tempered glass.
  • a light conversion member that separates the emitted light into two types of light components that vibrate parallel and perpendicular to the boundary surface between the tempered glass and the light extraction member, and converts the light into a bright line row or a dark line row;
  • the light incident on the light conversion member is monochromatic light having a central wavelength in a wavelength region where the extinction coefficient of the tempered glass is 4.5 mm ⁇ 1 or less. (Hereinafter, it may be called the surface stress measuring device of the glass of the present invention).
  • the said tempered glass is colored glass, It is characterized by the above-mentioned.
  • the light from the light source is monochromatic light having a central wavelength in a wavelength region where the extinction coefficient of the tempered glass is 4.5 mm ⁇ 1 or less.
  • the glass surface stress measuring apparatus according to the present invention comprises a bandpass filter or a monochromator for extracting monochromatic light in a wavelength region where the extinction coefficient of the tempered glass is 4.5 mm ⁇ 1 or less from the emitted light. It is provided between the light source and the tempered glass, or between the light extraction member and the light conversion member.
  • the light from the light source is monochromatic light in a wavelength region of 700 nm or more.
  • the light from the light source is monochromatic light in a wavelength region of 2000 nm or less.
  • the light source is a light emitting diode.
  • the light source is a laser.
  • the tempered glass has a minimum value of an extinction coefficient at a wavelength of 550 nm to 650 nm exceeding 1.7 mm ⁇ 1 .
  • the surface stress measuring apparatus of the glass of this invention Comprising:
  • the said tempered glass is colored by containing a metal ion, It is characterized by the above-mentioned.
  • the tempered glass is colored by depositing a metal colloid.
  • the tempered glass is colored by precipitating crystals.
  • the tempered glass is chemically strengthened.
  • the glass surface stress measurement apparatus is an image pickup device that picks up an image of a bright line row or dark line row converted by the light conversion member, and an image obtained by the image pickup device, and the bright line row or dark line row. And an image processing device for emphasizing the image.
  • the glass surface stress measuring apparatus comprises a measuring means for measuring the surface stress of the tempered glass based on the bright line array or dark line array converted by the light conversion member, the measuring means comprising: The photoelastic constant of the tempered glass at a wavelength substantially the same as that of monochromatic light having a central wavelength in a wavelength range of 4.5 mm ⁇ 1 or less is used.
  • the present invention is a method for measuring the surface stress of a tempered glass, the step of entering light from a light source into the surface layer of the tempered glass, and the step of propagating the light in the surface layer of the tempered glass.
  • the step of converting into a dark line array or bright line array and the step of measuring the surface stress of the tempered glass based on the dark line array or bright line array, and the light separated in the separating step is the tempered glass
  • a method for measuring the surface stress of glass that is monochromatic light having a central wavelength in a wavelength range of 4.5 mm ⁇ 1 or less (hereinafter sometimes referred to as the method for measuring the surface stress of glass of the present invention) is provided.
  • the glass surface stress measurement method of the present invention is characterized in that the tempered glass is colored. Further, in the glass surface stress measurement method of the present invention, the light from the light source is monochromatic light having a central wavelength in a wavelength region where the extinction coefficient of the tempered glass is 4.5 mm ⁇ 1 or less. And The glass surface stress measurement method of the present invention is also characterized in that the tempered glass taken out by using a bandpass filter or a monochromator emits monochromatic light having a wavelength range of 4.5 mm ⁇ 1 or less of the tempered glass. It enters into the surface layer of this.
  • the glass surface stress measurement method of the present invention is also characterized in that the tempered glass taken out using a bandpass filter or a monochromator is irradiated with monochromatic light having a wavelength range of 4.5 mm ⁇ 1 or less on the glass surface. It is characterized by being separated into two types of light components that vibrate in parallel and perpendicularly.
  • the monochromatic light is monochromatic light having a wavelength region of 700 nm or more.
  • the light from the light source is monochromatic light in a wavelength region of 2000 nm or less.
  • the tempered glass is characterized in that the minimum value of the extinction coefficient at a wavelength of 550 nm to 650 nm exceeds 1.7 mm ⁇ 1 .
  • the tempered glass is colored by containing metal ions.
  • the tempered glass is colored by depositing a metal colloid.
  • the tempered glass is colored by precipitating crystals.
  • the glass surface stress measurement method of the present invention is characterized in that the tempered glass is chemically strengthened. Further, the method for measuring the surface stress of the glass of the present invention, the step of imaging the converted bright line row or dark line row, and image processing for enhancing the bright line row or dark line row from the image obtained by the imaging. And measuring the surface stress of the tempered glass based on the emphasized bright line array or the dark line array. Further, in the glass surface stress measurement method of the present invention, the step of measuring the surface stress of the tempered glass includes monochromatic light having a central wavelength in a wavelength region where the extinction coefficient of the tempered glass is 4.5 mm ⁇ 1 or less. And using the photoelastic constant of the tempered glass at substantially the same wavelength.
  • the present invention it is possible to nondestructively measure the surface compressive stress and the surface compressive stress layer depth even with a colored tempered glass having a low transmittance in the visible region.
  • FIG. 1 the schematic of the surface stress measuring apparatus 10 of the glass of the 1st Embodiment of this invention is shown.
  • a prism made of optical glass is placed in optical contact with the surface of the tempered glass as a medium (light supply member) that makes light incident on the surface of the tempered glass that is the object to be measured.
  • a prism made of optical glass is placed in a state of being in optical contact with the surface of the tempered glass as a medium (light extraction member) for emitting light propagating through the surface layer of the tempered glass to the outside of the tempered glass.
  • light optically enters and exits through the prisms on the surface of the tempered glass those having a refractive index larger than that of the tempered glass are used.
  • a light source is arrange
  • the light conversion member is disposed in a direction in which light propagating through the surface layer of tempered glass is emitted from a prism that is a light extraction member.
  • the light conversion member vibrates in the emission direction of light propagated through the surface layer of tempered glass, parallel and perpendicular to the boundary surface between the tempered glass surface and the prism that is the light supply member, that is, the emission surface.
  • Each of these components is converted into a bright line row or a dark line row, respectively.
  • a means for observing the bright line array or the dark line array as an interference fringe image is provided. Using these apparatus configurations, the amount of compressive stress (CS, DOL) of the tempered glass is measured.
  • Chemically strengthened or air-cooled tempered glass has a compressive stress layer on the surface. These compressive stress layers have a higher refractive index than glass portions other than the compressive stress layer. These refractive indexes increase monotonously from the bottom to the surface of the compressive stress layer. Further, the birefringence of the compressive stress layer also monotonously increases toward the surface. Therefore, there are two depth versus refractive index curves for light oscillating perpendicular to the glass surface and light parallel to the glass surface, resulting in different optical waveguide effects and comparing the resulting interference fringe images. Thus, the surface compressive stress and the surface compressive stress layer depth of the tempered glass can be obtained.
  • the surface stress measuring apparatus 10 using the optical waveguide effect described above it is possible to obtain an interference fringe image composed of a bright line array or a dark line array by light oscillating perpendicularly to the glass surface and light oscillating parallel to the glass surface. It is essential.
  • the wavelength of light from the light source incident on the light supply member is centered in the wavelength region where the extinction coefficient of the tempered glass as the object to be measured is 4.5 mm ⁇ 1 or less.
  • a light source capable of emitting monochromatic light having a central wavelength in a wavelength region where the extinction coefficient of the to-be-measured object is 4.5 mm ⁇ 1 or less.
  • the incident light is absorbed by the influence of the contained metal ions and metal colloids, so that the emitted light may be very weak or unrecognizable.
  • the light source by making the light source as described above, the influence of light absorption by the tempered glass is reduced, and therefore, the surface stress layer can be measured with high accuracy.
  • the emitted light becomes weak for the reasons described above and it is difficult to recognize the interference fringe image, which is not preferable as the light source of the present invention.
  • any light source may be used as long as the light source itself can emit monochromatic light having a center wavelength in a wavelength region where the extinction coefficient of the tempered glass is 4.5 mm ⁇ 1 or less. Moreover, even if the light source is not monochromatic light, the light from the light source incident on the tempered glass is converted into monochromatic light by using means for monochromatic light such as a bandpass filter or a monochromator between the light source and the tempered glass. Also good. Even if the light source is monochromatic light, means for monochromatic light such as a bandpass filter or a monochromator may be used in order to make the light from the light source a monochromatic light with a narrower half-value width. By using monochromatic light with a narrow half-value width as the light source, the influence of other wavelengths can be eliminated as much as possible, and a clearer interference fringe image can be obtained.
  • means for monochromatic light such as a bandpass filter or a monochromator
  • the light from the light source is preferably monochromatic light having a wavelength range of 700 nm or more. This makes it possible to accurately measure the CS and DOL of the surface stress layer even with glass that does not substantially transmit visible light, such as black. In addition, in the conventional surface stress measuring apparatus and method, even a colored glass that transmits a part of visible light for which an interference fringe image could not be recognized due to the measurement wavelength can be measured.
  • the light from the light source can be used as long as it is monochromatic light in a wavelength region of 700 nm or more, but it is preferable to use a shorter wavelength in the infrared region.
  • the light from the light source is preferably monochromatic light having a wavelength range of 2000 nm or less, more preferably monochromatic light having a wavelength range of 1500 nm or less. Most preferred is monochromatic light having a wavelength range of 950 nm or less.
  • any kind of light source can be used as long as it can obtain a desired monochromatic light.
  • a light emitting diode or a laser can be preferably used. Since light emitting diodes having various center wavelengths are available, a light source corresponding to the extinction coefficient characteristic of the tempered glass can be appropriately selected. Further, since the life of the light source is long, the replacement frequency can be lowered.
  • Laser has high output, narrow half width, and can obtain linearly polarized monochromatic light. Therefore, it is possible to improve measurement accuracy without using a bandpass filter or the like. Further, by using a laser line filter, which is a kind of bandpass filter, in combination with a laser, it is possible to obtain monochromatic light with a very narrow half-value width.
  • a light source such as a xenon lamp, a metal halide lamp, or a mercury lamp can be used.
  • the light supply member and the light extraction member can each be a prism made of optical glass having a refractive index higher than that of tempered glass. Further, the light supply member prism and the light extraction member prism may be separate as shown in FIG. 1 or may be integrated. Further, the light shielding means may be sandwiched between these prisms and integrated. The light shielding means is used for the purpose of eliminating unnecessary ambient light from entering a prism that is a light extraction member. As the light shielding means, a shielding plate made of metal or the like, or a shielding film made of a metal thin film can be used.
  • a liquid whose refractive index is similar to that of each prism is interposed between the tempered glass and each prism. And may be optically contacted.
  • the light conversion member is for observing light emitted from the surface layer by the light from the light source being incident on the surface layer of the tempered glass, propagating through the surface layer.
  • the light emitted from the tempered glass causes birefringence between the light whose direction of vibration is along the glass surface and the light perpendicular to the surface due to the surface compressive stress of the surface layer. Both have the same refractive index gradient, but have different refractive angles because of different effective refractive indexes. Therefore, it is possible to measure CS and DOL by observing both the dark line caused by the light oscillating in the direction perpendicular to the dark line caused by the light oscillating in the direction parallel to the incident surface of the emitted light.
  • a single or a plurality of polarizing plates are used.
  • a method of manually reading the scale using an eyepiece micrometer a solid-state image pickup device such as a CCD or CMOS arranged on the focal plane is obtained.
  • a method of calculating CS or DOL by analyzing the interference fringe image can be used.
  • a band pass filter, a monochromator, or the like may be disposed in front of the polarizing plate.
  • a structure of a light conversion member not only the said form but a well-known thing can be used.
  • FIG. 2 the schematic of the surface stress measuring apparatus 20 of the glass of the 2nd Embodiment of this invention is shown.
  • the glass surface stress measuring device 20 of the second embodiment is a band-pass filter that extracts monochromatic light in a wavelength region where the extinction coefficient of the tempered glass to be measured is 4.5 mm ⁇ 1 or less from the light emitted from the light extraction member.
  • the surface stress of the glass according to the first embodiment described with reference to FIG. 1 except that a monochromator is provided between the light extraction member and the light conversion member, and light from the light source is not limited to monochromatic light. Since the configuration is the same as that of the measuring apparatus 10, the description thereof is omitted.
  • a light source When measuring glass that hardly transmits visible light, for example, black, it is preferable to use a light source with a large amount of light in order to use light in a wavelength region that can pass through the glass for measurement. At that time, even if the light source itself does not emit monochromatic light, it is equipped with a band-pass filter or monochromator that takes out monochromatic light of a specific wavelength between the light extraction member and the light conversion member, so that a monochromatic light with a certain amount or more is obtained. Light can be obtained, whereby a clear interference fringe image can be obtained.
  • the monochromatic light extracted by the bandpass filter or the monochromator needs to be light in a wavelength region where the extinction coefficient of the tempered glass to be measured is 4.5 mm ⁇ 1 or less.
  • Use of monochromatic light having a wavelength range in which the extinction coefficient of the tempered glass exceeds 4.5 mm ⁇ 1 is not preferable because light entering the light conversion member becomes weak and makes it difficult to recognize an interference fringe image.
  • the light source having a large light amount a known light source such as a xenon lamp, a metal halide lamp, or a mercury lamp can be used. Further, in order to eliminate the influence other than the desired wavelength from the light emitted from the light extraction member, it is preferable that the bandpass filter or the monochromator can extract monochromatic light having a half-value width as narrow as possible.
  • monochromatic light extracted using a bandpass filter or a monochromator monochromatic light having a wavelength range of 700 nm or more is preferably used. This makes it possible to accurately measure the CS and DOL of the surface stress layer even with glass that does not substantially transmit visible light, such as black. In addition, in the conventional surface stress measuring apparatus and method, even a colored glass that transmits a part of visible light for which an interference fringe image could not be recognized due to the measurement wavelength can be measured. Note that monochromatic light extracted using a band-pass filter or a monochromator can be used as long as it is monochromatic light having a wavelength region of 700 nm or more, but it is preferable to use a shorter wavelength in the infrared region.
  • the monochromatic light is preferably monochromatic light having a wavelength range of 2000 nm or less, and more preferably monochromatic light having a wavelength range of 1500 nm or less. Most preferred is monochromatic light having a wavelength range of 950 nm or less.
  • FIG. 3 is a schematic view of a glass surface stress measuring apparatus 30 according to a third embodiment of the present invention.
  • the glass surface stress measuring device 30 and the glass surface stress measuring method of the third embodiment of the present invention will be described.
  • Colored glass has lower light transmittance than conventional transparent glass, so the boundary between bright line or dark line array obtained by the light conversion member is blurred, and accurate surface stress (CS, DOL) May not be calculated.
  • the surface compressive stress depth (DOL) is specified by interference fringes formed by light reflected from the deepest portion in the depth direction.
  • the obtained bright line array or dark line array image is subjected to image processing, and the bright line array or dark line array is emphasized to calculate a more accurate surface stress amount (CS, DOL). I am doing so.
  • the configuration of the glass surface stress measuring apparatus 30 according to the third embodiment will be described with reference to FIG. 3, but the glass according to the first and second embodiments described with reference to FIGS.
  • symbol is attached
  • the glass surface stress measurement device 30 includes a light source 2, a bandpass filter 3, a light supply member 4, a light extraction member 5, a light conversion member 6 ⁇ / b> A, and an image processing device 11. .
  • FIG. 4 is a schematic diagram showing the configuration of the light conversion member 6A provided in the glass surface stress measurement device 30.
  • the light conversion member 6A includes a lens 6a, a polarizing plate 6b, an image sensor 6c, and a housing 6d.
  • the lens 6 a converges the light emitted from the light extraction member 5.
  • the polarizing plate 6 b separates two types of light components that vibrate in parallel and perpendicular to the boundary surface between the tempered glass 1 and the light extraction member 5 from the light emitted from the light extraction member 5.
  • the light that has passed through the polarizing plate 6b is recognized as a bright line array or a dark line array.
  • IR infrared
  • the imaging element 6c is an image sensor (for example, a CCD (Charge-Coupled Device) image sensor, a CMOS (Complementary Metal-Oxide Semiconductor) image sensor) for observing a bright line array or a dark line array as an interference fringe image.
  • the image sensor 6c photoelectrically converts the received light and outputs the luminance value for each of the plurality of pixels constituting the image to the image processing apparatus 11 as digital image data.
  • FIG. 5 is a schematic diagram showing the configuration of the image processing apparatus 11 provided in the glass surface stress measurement apparatus 30.
  • the image processing apparatus 11 includes an image correction unit 11a, an enhancement unit 11b, a D / A converter 11c, and a display 11d.
  • the image correction unit 11a performs white balance adjustment and ⁇ correction on the digital image data output from the image sensor 6c.
  • the emphasis unit 11b emphasizes the contrast of the digital image data after correction, and emphasizes the bright line row or the dark line row.
  • the following method can be adopted as a method for enhancing the contrast of the bright line array or the dark line array.
  • the following method may be applied to the entire interference fringe image obtained by the imaging device 6c, or may be applied only to a specific image area where light attenuation is large.
  • image processing that emphasizes only the image area corresponding to the periphery of the deepest part may be performed.
  • the bright line row or the dark line row is emphasized by binarizing the luminance value of each pixel constituting the image with a threshold value stored in advance. For example, when the luminance value is set from 0 (minimum luminance: black) to 255 (maximum luminance: white), the luminance value of a pixel having a luminance value exceeding the threshold value (for example, 127) is set to 255, and the threshold value (for example, 127) It can be binarized by setting the luminance value of a pixel having a luminance value equal to or less than 0 to 0.
  • the bright line row or the dark line row is emphasized by enhancing the outline (edge).
  • an existing edge enhancement filter for example, a sharpness filter
  • the D / A converter 11c converts the digital image data in which the bright line row or dark line row is emphasized into analog image data that can be displayed on the display 11d.
  • the display 11d is, for example, a liquid crystal display or a CRT (Cathode Ray Tube), and displays an image corresponding to the analog image data output from the D / A converter 11c on the screen.
  • FIG. 6 is a schematic diagram of bright line rows or dark line rows displayed on the display 11d.
  • the bright line row or dark line row on the left side of FIG. 6 is the bright line row or dark line row of the light component that vibrates perpendicularly to the boundary surface between the tempered glass 1 and the light extraction member 5.
  • the bright line row or dark line row on the right side of FIG. 6 is the bright line row or dark line row of the light component that vibrates parallel to the boundary surface between the tempered glass 1 and the light extraction member 5.
  • the surface compressive stress (CS) and the surface compressive stress layer depth (DOL) can be calculated. Specifically, the distance difference ⁇ t between the bright line array or the dark line array of two types of light components that vibrate parallel and perpendicular to the boundary surface between the tempered glass 1 and the light extraction member 5 separated by the light conversion member 6A.
  • the surface compressive stress (CS) can be calculated from (see FIG. 6).
  • the surface compressive stress layer depth (DOL) can be calculated from the number of bright line rows or dark line rows.
  • the photoelastic constant Kc is used for the calculation of the surface compressive stress (CS) and the surface compressive stress layer depth (DOL), this photoelastic constant Kc is actually substantially the same as the light source incident on the tempered glass.
  • the photoelastic constant of the tempered glass at a wavelength is preferred. That is, it is the photoelastic constant of the tempered glass at substantially the same wavelength as the monochromatic light having the central wavelength in the wavelength region where the extinction coefficient of the tempered glass incident on the light conversion member is 4.5 mm ⁇ 1 or less. This is because the photoelastic constant obtained depends on the wavelength used.
  • the substantially same wavelength means a wavelength within a range of several nm to several tens of nm centering on the same wavelength.
  • the photoelastic constant Kc is a constant representing the relationship between the stress F and the optical path difference ⁇ due to birefringence, and satisfies the relationship of the following equation (1), where d is the thickness of the glass.
  • ⁇ Kc ⁇ d ⁇ F (1)
  • the tempered glass which is a measuring object of the surface compressive stress (CS) and the surface compressive stress layer depth (DOL) is a colored glass
  • the tempered glass passes through the tempered glass.
  • the amount of light to be performed is not sufficient and the photoelastic constant Kc cannot be measured, or an accurate value of the photoelastic constant Kc cannot be obtained.
  • the tempered glass is thin, the tempered glass cannot withstand the applied stress and may be damaged.
  • FIG. 7 is a diagram for explaining a method of measuring the photoelastic constant Kc in the present invention.
  • a method for measuring the photoelastic constant Kc in the present embodiment will be described with reference to FIG.
  • a method for measuring the photoelastic constant Kc will be described by taking as an example a four-point bending method in which force F is applied from four points to the tempered glass 1 having the photoelastic constant Kc to apply a bending stress.
  • the tempered glass 1 From the light source 101, the tempered glass 1 has a central wavelength in a wavelength region where the extinction coefficient is 4.5 mm ⁇ 1 or less, and monochromatic light in a wavelength region of 700 nm to 2000 nm, more preferably 700 nm to 1500 nm. Monochromatic light is emitted.
  • the wavelength of the monochromatic light of the light source 101 is substantially the same as the wavelength of the light incident on the light conversion member of the glass surface stress measurement device.
  • the polarizing plates 102 and 104 are arranged so that they are orthogonal to each other, that is, have a phase difference of 90 degrees, with the tempered glass 1 and the Babinet correction plate 103 that are the objects of measurement of the photoelastic constant Kc interposed therebetween.
  • the polarizing plate 102 allows only the light component polarized in a specific direction out of the light emitted from the light source 101.
  • the polarizing plate 104 allows only the light component polarized in the direction orthogonal to the polarizing direction of the polarizing plate 102 among the light transmitted through the tempered glass 1 to pass therethrough.
  • the Babinet correction plate 103 is a compensation plate made of quartz.
  • the photodetector 105 receives the light that has passed through the polarizing plate 104.
  • the force F is applied by a load application mechanism (not shown) such as a loader.
  • the thickness of the tempered glass 1 is set to a thickness that allows light from the light source 101 to pass therethrough, and the load application direction is not the thickness direction of the tempered glass 1, but the tempered glass 1
  • the force F is applied from the thick side. For this reason, it is possible to suppress the possibility that the amount of light passing through the tempered glass is not sufficient and the photoelastic constant Kc cannot be measured and that the accurate value of the photoelastic constant Kc cannot be obtained. Further, the tempered glass 1 cannot withstand the load to which it is applied and can be prevented from being damaged.
  • the surface stress amount (CS, DOL) of the tempered glass 1 can be measured more accurately.
  • the photoelastic constant Kc used when calculating the surface compressive stress (CS) and the surface compressive stress layer depth (DOL) the light is actually incident on the light conversion member of the surface stress measuring device of the tempered glass 1.
  • Light having substantially the same wavelength as the light to be emitted that is, monochromatic light having a central wavelength in a wavelength region where the extinction coefficient of tempered glass is 4.5 mm ⁇ 1 or less and having a wavelength region of 700 nm to 2000 nm.
  • the light used for measuring the photoelastic constant Kc is more preferably monochromatic light having a wavelength range of 700 nm to 2000 nm.
  • the object of the present invention is to measure the surface stress of tempered glass in which the glass itself is colored.
  • Examples of the colored tempered glass include the following forms.
  • the glass As a 1st form, it is glass which contains a metal ion in tempered glass and was colored by absorption of the light of the specific wavelength by a metal ion.
  • the transition metal element or rare earth element contained in the glass is an element having a plurality of valences
  • the glass has a specific color due to the influence of the wavelength of light that is selectively absorbed by the transition of electrons. Since the transition metal ion dissolved in the glass is strongly influenced by the anion adjacent to the outer shell, the wavelength of light that is selectively absorbed is influenced by factors such as the basic glass composition, the melting atmosphere, and the additive components.
  • the rare earth element atoms are completely filled with electrons in the electron orbit close to the outer shell, and incomplete in the electron orbits inside, the electron transition occurs in the inner orbits and light Since selective absorption of the wavelength is performed, the color is almost constant without being affected by the basic glass or the molten atmosphere.
  • the glass can be colored blue by containing Cu 2+ in the glass.
  • rare earth elements it can be set as the glass colored pink by containing Er3 + in glass.
  • glass containing metal colloid in tempered glass and colored with metal colloid As a second form, glass containing metal colloid in tempered glass and colored with metal colloid.
  • colloids smaller than the wavelength of light are present in the glass, the glass is colored by absorbing specific (wavelength) light. For example, a colloid of gold or copper is precipitated in the glass, whereby a red colored glass can be obtained.
  • a third form is a glass that is recognized as milky white by scattering incident light by precipitating crystalline particles on tempered glass.
  • the colored tempered glass described above has different wavelengths to be absorbed depending on coloring components and the like.
  • the wavelength of light from the light source is monochromatic light having a central wavelength in a wavelength region where the extinction coefficient of the tempered glass is 4.5 mm ⁇ 1 or less.
  • the incident fringe image can be clearly recognized from the emitted light without being absorbed by the coloring component when the incident light propagates through the surface layer.
  • the tempered glass may have a minimum value of an extinction coefficient of light having a wavelength of 550 nm to 650 nm exceeding 1.7 mm ⁇ 1 . Glass having such an extinction coefficient cannot recognize an interference fringe image with a conventional surface stress measurement device.
  • the interference fringe image can be recognized, there is a problem that it is unclear and it is difficult to automatically process the image.
  • the present inventor measured a colored tempered glass having a minimum extinction coefficient of light having a wavelength of 550 nm to 650 nm slightly exceeding 1.7 mm ⁇ 1 using a conventional surface stress measuring device, and found an interference fringe image. I could't recognize it.
  • the interference fringe image can be clearly recognized and accurately detected. It is possible to measure the surface stress.
  • the air-cooling strengthening method is a method in which a cold wind is applied to a glass plate once heat-treated to cool it, thereby forming a compressive stress on the surface.
  • the chemical strengthening method for example, by placing soda lime glass in a potassium nitrate molten salt heated to about 380 ° C., ion exchange of alkali ions (sodium ions as glass components in molten salt having a larger ion radius) This is a method of forming compressive stress on the glass surface by ion exchange with potassium ions.
  • each of the strengthening treatments forms a surface compression layer on the surface layer of the glass, and they have a refractive index different from that of the glass portion other than the surface compression layer. Therefore, any tempered glass subjected to any tempering treatment can be measured by the surface compression measuring apparatus and method of the present invention using the optical waveguide effect of the surface layer.
  • the tempered glass includes a glass having a multilayer structure in which glasses having different thermal expansion coefficients are laminated, and the case where the surface layer glass is colored glass is also included in the form.
  • the glass in which the surface of the glass serving as the core is coated with a colored soot having a different thermal expansion coefficient from that of the glass serving as the core is also included in the form of the colored glass.
  • the glasses A to D were immersed in KNO 3 molten salt at 450 ° C. for 6 hours to be chemically strengthened.
  • these glasses A to D were analyzed for potassium concentration in the depth direction using EPMA, ion exchange occurred from the surface to a depth of about 30 ⁇ m, and a compressive stress layer was formed.
  • FIG. 8 shows the relationship between the absorption coefficient and the wavelength of Glass A and Glass B.
  • glass A to glass D it was confirmed whether or not an interference fringe image could be observed with a surface stress measurement device when a sodium lamp was used as the light source and a wavelength of 600 nm was used as the measurement light.
  • the absorption coefficient of glass A at a wavelength of 600 nm is 5.7 mm ⁇ 1
  • the absorption coefficient of glass B at a wavelength of 600 nm is 1.37 mm ⁇ 1
  • the absorption coefficient of glass C at a wavelength of 600 nm is 5.47 mm ⁇ 1
  • the absorption coefficient of glass D at a wavelength of 600 nm is 1.37 mm ⁇ 1 .
  • glass B was able to observe an interference fringe image, whereas glass A could not confirm the interference fringe image. This is presumably because the incident light having a wavelength of 600 nm is absorbed when propagating through the surface layer of the glass A, and the emitted light is extremely weak.
  • a xenon lamp was used as the light source, a bandpass filter was placed between the light extraction member (prism) and the light conversion member, and it was confirmed whether an interference fringe image could be observed with a surface stress measurement device.
  • the band pass filter used what selectively permeate
  • an interference fringe image of glass A could be confirmed. This is presumably because incident light with a wavelength of 850 nm was partially absorbed when propagating through the surface layer of glass A, but its attenuation was small and could be recognized as emitted light.
  • interference fringe images observed with the surface stress measuring apparatus for glass C and glass D are shown in FIGS.
  • the glass C could not observe an interference fringe image.
  • Glass D was able to confirm an interference fringe image.
  • the boundary on the right side of the interference fringe image (the portion indicating the depth of the compressive stress layer) is unclear, and an accurate value cannot be obtained by calculating DOL using the automatic processing of the surface stress measurement device. It was.
  • the absorption coefficient at a wavelength of 790nm of the glass C is 1.12 mm -1 and the absorption coefficient at a wavelength of 790nm of the glass D is 0.16 mm -1.
  • FIGS. 11 and 12 show interference fringe images observed with a surface stress measuring device for glass C and glass D.
  • FIG. As a result, both the glass C and the glass D were able to confirm interference fringe images.
  • an accurate value could be obtained by calculating the DOL using the automatic processing of the surface stress measuring device.
  • each optical system such as the light source and the light conversion member, and the combination of these components are not limited to those illustrated, but can be changed within the scope of the measurement principle.
  • CS, DOL surface stress amount
  • the surface stress amount (CS, DOL) of the colored tempered glass having low transmittance in the visible region can be accurately measured nondestructively. Is possible.

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Abstract

L'invention porte sur un dispositif pour mesurer une contrainte de surface d'un verre, lequel dispositif comporte : une source de lumière ; un élément d'apport de lumière qui permet à de la lumière provenant de la source de lumière d'entrer dans une couche de surface d'un verre trempé ; un élément d'extraction de lumière qui permet à de la lumière se déplaçant dans la couche de surface du verre trempé d'être émise vers l'extérieur du verre trempé ; et un élément de conversion de lumière qui sépare la lumière émise en deux types de composantes de lumière vibrant parallèlement à une surface de limite du verre trempé et de l'élément d'extraction de lumière et perpendiculairement à celle-ci, et qui convertit les composantes de lumière sous la forme d'une ligne d'émission ou d'une ligne noire. Dans le dispositif, le verre trempé est un verre coloré, et la lumière provenant de la source de lumière est une lumière monochrome ayant la longueur d'onde centrale dans une plage de longueurs d'onde où un coefficient d'absorption du verre trempé est de 4,5 mm-1 ou moins.
PCT/JP2012/056745 2011-03-18 2012-03-15 Dispositif pour mesurer une contrainte de surface de verre et procédé pour mesurer une contrainte de surface de verre Ceased WO2012128184A1 (fr)

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CN104316245A (zh) * 2014-11-03 2015-01-28 苏州精创光学仪器有限公司 玻璃表面应力检测装置
US8957374B2 (en) 2012-09-28 2015-02-17 Corning Incorporated Systems and methods for measuring birefringence in glass and glass-ceramics
CN104374501A (zh) * 2014-11-07 2015-02-25 西安科技大学 一种基于光干涉法测玻璃体应力的测量方法
US9261429B2 (en) 2014-05-21 2016-02-16 Corning Incorporated Prism-coupling systems and methods for characterizing large depth-of-layer waveguides
JP2016142600A (ja) * 2015-01-30 2016-08-08 有限会社折原製作所 表面応力測定方法、表面応力測定装置
JP2016535854A (ja) * 2013-08-29 2016-11-17 コーニング インコーポレイテッド プリズム結合システム及び湾曲部品を特徴付ける方法
CN106770056A (zh) * 2017-03-10 2017-05-31 苏州精创光学仪器有限公司 钢化玻璃识别仪及识别方法
JP2017519190A (ja) * 2014-04-23 2017-07-13 コーニング インコーポレイテッド 応力のプリズム結合測定におけるコントラストの向上方法
WO2018056121A1 (fr) * 2016-09-26 2018-03-29 有限会社折原製作所 Dispositif de mesure de contrainte pour verre trempé, procédé de mesure de contrainte pour verre trempé, procédé de fabrication de verre trempé et verre trempé
JPWO2017115811A1 (ja) * 2015-12-28 2018-10-18 有限会社折原製作所 表面屈折率測定方法、及び、それを利用した表面応力測定方法
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US8957374B2 (en) 2012-09-28 2015-02-17 Corning Incorporated Systems and methods for measuring birefringence in glass and glass-ceramics
US10156488B2 (en) 2013-08-29 2018-12-18 Corning Incorporated Prism-coupling systems and methods for characterizing curved parts
US10495530B2 (en) 2013-08-29 2019-12-03 Corning Incorporated Prism-coupling systems and methods for characterizing curved parts
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US11079280B2 (en) 2013-10-30 2021-08-03 Corning Incorporated Apparatus and methods for measuring mode spectra for ion-exchanged glasses having steep index region
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US9261429B2 (en) 2014-05-21 2016-02-16 Corning Incorporated Prism-coupling systems and methods for characterizing large depth-of-layer waveguides
JP7072615B2 (ja) 2014-05-21 2022-05-20 コーニング インコーポレイテッド 導波路の特性を評価する方法
US11384011B2 (en) 2014-07-17 2022-07-12 Corning Incorporated Glass sheet and system and method for making glass sheet
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CN104316245A (zh) * 2014-11-03 2015-01-28 苏州精创光学仪器有限公司 玻璃表面应力检测装置
CN104374501A (zh) * 2014-11-07 2015-02-25 西安科技大学 一种基于光干涉法测玻璃体应力的测量方法
JP2016142600A (ja) * 2015-01-30 2016-08-08 有限会社折原製作所 表面応力測定方法、表面応力測定装置
JPWO2017115811A1 (ja) * 2015-12-28 2018-10-18 有限会社折原製作所 表面屈折率測定方法、及び、それを利用した表面応力測定方法
KR20190059903A (ko) * 2016-09-26 2019-05-31 오리하라 인더스트리얼 컴퍼니 리미티드 강화 유리의 응력 측정 장치, 강화 유리의 응력 측정 방법, 강화 유리의 제조 방법, 강화 유리
JPWO2018056121A1 (ja) * 2016-09-26 2019-07-04 有限会社折原製作所 強化ガラスの応力測定装置、強化ガラスの応力測定方法、強化ガラスの製造方法、強化ガラス
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KR102345803B1 (ko) 2016-09-26 2022-01-03 오리하라 인더스트리얼 컴퍼니 리미티드 강화 유리의 응력 측정 장치, 강화 유리의 응력 측정 방법, 강화 유리의 제조 방법, 강화 유리
US11274981B2 (en) 2016-09-26 2022-03-15 Orihara Industrial Co., Ltd. Stress measurement device for strengthened glass, stress measuring method for strengthened glass, manufacturing method of strengthened glass, and strengthened glass
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WO2018056121A1 (fr) * 2016-09-26 2018-03-29 有限会社折原製作所 Dispositif de mesure de contrainte pour verre trempé, procédé de mesure de contrainte pour verre trempé, procédé de fabrication de verre trempé et verre trempé
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