TWI872869B - Portable pyrometer calibration device - Google Patents

Abstract

A portable pyrometer calibration device is configured for calibrating a pyrometer. The portable pyrometer calibration device includes a handheld interface unit, a blackbody simulator, and a fiber optic light guide. The handheld interface unit is configured to be connected to the pyrometer. The blackbody simulator includes a light source and a beam adjustment structure. The light source has an elliptical divergent beam corresponding to a simulated blackbody temperature spectrum. The beam adjustment structure is arranged in a relative position corresponding to the light source to collimate and transform the elliptical divergent beam into a circular parallel beam. The fiber optic light guide guides the circular parallel beam and has a receiving end and an emitting end opposite to each other, the receiving end is connected to the blackbody simulator, and the emitting end is connected to the handheld interface unit.

Description

Portable pyrometer calibration device

The present invention relates to a pyrometer calibration device, in particular to a portable pyrometer calibration device.

According to the principle of blackbody radiation law, the radiation intensity of a blackbody is proportional to its temperature. Based on this, a high-temperature blackbody furnace, as a blackbody radiation source, can be used to calibrate and test high-temperature radiation thermometers (pyrometers) to ensure the accuracy of the pyrometer. Generally speaking, after sensing the blackbody radiation of a blackbody furnace, a pyrometer will output the sensed temperature reading, which is compared with the actual temperature of the blackbody furnace. In the case of a mismatch between the two, the pyrometer parameters are adjusted to match the output temperature reading with the actual temperature of the blackbody furnace to achieve the calibration of the pyrometer.

However, the size of a traditional blackbody furnace is usually large and not easy to move, so it cannot be transported to the site where the pyrometer is located. The pyrometer must be transported to a laboratory for calibration, which is very time-consuming and adds additional costs. In addition, since the heating and stabilization process of the blackbody furnace takes a long time, it is usually time-consuming to use a traditional blackbody furnace to calibrate the pyrometer. In addition, the operation of a traditional blackbody furnace must be in a high-temperature environment, and the pyrometer must be aligned under strong light, so the calibration operation must be performed by trained authorized personnel, which increases the complexity and cost of the operation. In addition, the traditional blackbody furnace uses a high-power heating graphite tube, which poses a safety problem of high temperature hazards to operators and leads to high carbon emissions. Furthermore, since the graphite tube is a consumable material, its service life is only about 48 hours, so the graphite tube in the black body furnace needs to be replaced regularly, which increases the cost.

The present invention provides a portable pyrometer calibration device to solve the problems of the traditional black body furnace in the prior art that the traditional black body furnace is too large to be moved to the site, the pyrometer calibration of the traditional black body furnace is time-consuming, the operation of the traditional black body furnace requires a high temperature environment and uses a high power consumption graphite tube to heat the furnace, which easily causes high temperature hazards to the operator, and the graphite tube in the black body furnace needs to be replaced regularly, which increases the cost and leads to high carbon emissions.

The portable pyrometer calibration device disclosed in one embodiment of the present invention is used to calibrate a pyrometer. The portable pyrometer calibration device includes a handheld docking unit, a black body simulator and an optical fiber light guide tube. The handheld docking unit is used to dock with the pyrometer. The black body simulator includes a light source and a beam adjustment structure. The light source has an elliptical divergent beam corresponding to a black body temperature simulation spectrum, and the beam adjustment structure is arranged at a relative position corresponding to the light source to collimate and transform the elliptical divergent beam into a circular parallel beam. The optical fiber light guide tube guides the circular parallel beam and has a relative light receiving end and a light emitting end, the light receiving end is connected to the black body simulator, and the light emitting end is connected to the handheld docking unit.

According to the portable pyrometer calibration device disclosed in the above-mentioned embodiment, the blackbody temperature simulation spectrum used to calibrate the pyrometer is generated by the blackbody simulator, which can be used as a stable calibration heat source, so that the portable pyrometer calibration device has the advantage of small size, and can be used on site due to its portable design. In addition, the blackbody simulator uses low-power cold light, which can avoid the problem of high temperature hazards during the calibration process, and there is no need to regularly replace consumables, which can reduce carbon emissions. In addition, the light source of the blackbody simulator can be heated to a predetermined temperature in a short time, so that the portable pyrometer calibration device can be heated up in less than 10 minutes, which is conducive to rapid installation and calibration on site. Furthermore, the elliptical divergent beam of the light source is collimated and transformed into a circular parallel beam through the beam adjustment structure, which can provide a black body temperature simulation spectrum that meets the pyrometer's light receiving angle range, thereby effectively utilizing the light source energy. In addition, by docking the pyrometer with a handheld docking unit, the light output end of the optical fiber light guide can be easily aligned with the pyrometer.

The above description of the content of the present invention and the following description of the implementation method are used to demonstrate and explain the principle of the present invention, and provide a further explanation of the scope of the patent application of the present invention.

1: Portable pyrometer calibration device

2: Blackbody simulator

20,20b: Light source

21,21b: Beam adjustment structure

211,211b: Collimator lens set

E11: Circular symmetric lens, first cylindrical lens

E12: Second cylindrical lens

212,212b: Deformed lens set

E21: First deformation prism

S1: First incident surface

S2: First exit surface

E22: Second Deformed Prism

S3: Second incident surface

S4: Second exit surface

213b: homogenizing mirror set

E31: First micro-array lens

E32: Second micro-array lens

E33: Plano-convex lens

E34: Diffusive tablets

3,3b: Fiber optic light guide tube

31,31b: light receiving end

32: Light output end

4: Handheld docking unit

9: Thermometer

L1: Elliptical divergent beam

L2: Elliptical collimated beam

L3: Circular parallel beam

CL1: optical axis

CL2: Center axis

θ1,θ2: angle, sharp angle

θ3,θ4: angle of intersection

D1: Distance

X: X-axis direction

Y: Y-axis direction

FIG1 is a schematic diagram of a portable pyrometer calibration device and a pyrometer according to the first embodiment of the present invention.

FIG2 is a schematic diagram of the light source and beam adjustment structure of the black body simulator and a part of the optical fiber light guide tube of the portable pyrometer calibration device of FIG1.

FIG3 is a schematic diagram of the laser beam profile distribution of an implementation of the light source in FIG2.

FIG4 is a partial schematic diagram of the light source and beam adjustment structure of the black body simulator and the optical fiber light guide tube of the portable pyrometer calibration device according to the second embodiment of the present invention.

FIG5 is a partial schematic diagram of the light source and beam adjustment structure of the black body simulator and the optical fiber light guide tube of the portable pyrometer calibration device according to the third embodiment of the present invention.

FIG6 is a partial schematic diagram of the light source and beam adjustment structure of the black body simulator and the optical fiber light guide tube of the portable pyrometer calibration device according to the fourth embodiment of the present invention.

FIG7 is a partial schematic diagram of the light source and beam adjustment structure of the black body simulator and the optical fiber light guide tube of the portable pyrometer calibration device according to the fifth embodiment of the present invention.

FIG8 is a partial schematic diagram of the light source and beam adjustment structure of the black body simulator and the optical fiber light guide tube of the portable pyrometer calibration device according to the sixth embodiment of the present invention.

The detailed features and advantages of the embodiments of the present invention are described in detail in the following implementation method. The content is sufficient to enable any person with ordinary knowledge in the field to understand the technical content of the embodiments of the present invention and implement it accordingly. According to the content disclosed in this specification, the scope of the patent application and the drawings, any person with ordinary knowledge in the field can easily understand the relevant purposes and advantages of the present invention. The following embodiments are to further illustrate the viewpoints of the present invention, but do not limit the scope of the present invention by any viewpoint.

Please refer to Figures 1 and 2. Figure 1 is a schematic diagram of a portable pyrometer calibration device and a pyrometer according to the first embodiment of the present invention, and Figure 2 is a schematic diagram of a light source and a beam adjustment structure of a black body simulator and a part of an optical fiber light guide tube of the portable pyrometer calibration device of Figure 1.

The portable pyrometer calibration device 1 of this embodiment is used to calibrate a pyrometer 9. The pyrometer 9 may be a high temperature radiation thermometer. For example, the pyrometer 9 is a high temperature radiation thermometer using a fluke endurance E1RL as a sensing element, with an incident light half angle of about 1.098 degrees and an incident light numerical aperture (NA) of 0.019, a working distance of 600 mm, a sensing spectrum center wavelength of the sensing element of 1.0 micrometer, and a material of the sensing element of silicon (Si). Alternatively, the pyrometer 9 is, for example, a high-temperature radiation thermometer using chino IR-FAS IR-FL5AH02 as a sensing element, whose light entry half angle is about 0.955 degrees and light entry numerical aperture (NA) is 0.017, whose working distance is 150 mm, whose sensing spectrum center wavelength of the sensing element is 0.9 microns, and whose sensing element is made of silicon. Alternatively, the pyrometer 9 is, for example, a LP3/LP4 series high-temperature radiation thermometer of the German KE company, whose light entry half angle is about 1.814 degrees and light entry numerical aperture (NA) is 0.032, whose working distance is 600 mm, and whose sensing spectrum center wavelength of the sensing element is 0.9 microns. Alternatively, the pyrometer 9 is, for example, the MR1SASF high temperature radiation thermometer of Raytek Corporation of the United States, whose light entry half angle is about 1.098 degrees and light entry numerical aperture (NA) is 0.019, whose working distance is 600 mm, and whose sensing element has a sensing spectrum center wavelength of 1.0 micron.

The portable pyrometer calibration device 1 includes a black body simulator 2, a handheld docking unit 4, and an optical fiber light guide 3. In one embodiment, the size of the black body simulator 2 can be 30 cm × 30 cm × 14 cm. Compared with the traditional black body furnace, the black body simulator 2 has the advantage of small size and is portable and can be used on site. The black body simulator 2 includes a light source 20, a thermoelectric cooler (not shown), a light source controller (not shown), and a beam adjustment structure 21.

The light source 20 has an elliptical divergent light beam L1 corresponding to a black body temperature simulation spectrum, and the light source 20 can be, for example, a broadband superluminescent diode (SLD), an LED light source, a laser diode light source, or a multi-wavelength light source, but the present invention is not limited thereto. The light source 20 has a light-emitting layer, and the light-emitting layer can be used to generate light of different wavelengths or a single wavelength. Thus, compared to a traditional black body furnace, the black body simulator 2 of this embodiment uses low-power cold light, which can avoid the problem of high temperature hazards during the calibration process, and there is no need to regularly replace consumables. Specifically, the traditional black body furnace heats up by burning graphite tubes, and the graphite tubes need to be replaced frequently. The long heating time means that the black body furnace needs to heat up for at least 3 hours. Compared with the traditional black body furnace, the light source 20 of this embodiment has the advantage of a long service life, which can generally be used for at least 10,000 hours. In addition, the light source 20 can heat up to a predetermined temperature in a short time, so that the portable pyrometer calibration device 1 can complete the heat-up in less than 10 minutes, which is conducive to rapid installation and calibration on site.

Please refer to FIG. 3 and Table 1 below, where FIG. 3 is a schematic diagram of the laser beam profile distribution of an implementation of the light source of FIG. 2 . The beam diameter of the light beam emitted by the light source 20 in the X-axis direction is relatively large and the numerical aperture (NA) is 0.59, while the beam diameter in the Y-axis direction perpendicular to the X-axis direction is relatively small and the numerical aperture (NA) is 0.15. According to actual use requirements, for example, the portion of the beam radius from the beam center to the distance where the light intensity decays to the half-maximum width (FWHM) can be regarded as an effective beam and used as an elliptical divergent beam L1, or the portion of the beam radius from the beam center to the distance where the light intensity decays to 13.5% (1/e ² ) of the peak value can be regarded as an effective beam and used as an elliptical divergent beam L1, but the present invention is not limited thereto.

When the beam radius is the distance from the center of the beam to the light intensity decaying to half the width as the effective beam and is taken as the elliptical divergent beam L1, the irradiance of the beam in the X-axis direction is 43.9 degrees and the irradiance in the Y-axis direction is 9.5 degrees. When the beam radius is the distance from the center of the beam to the light intensity decaying to 13.5% of the peak value as the effective beam and is taken as the elliptical divergent beam L1, the irradiance of the beam in the X-axis direction is 72.4 degrees and the irradiance in the Y-axis direction is 16.9 degrees.

A sensor in the pyrometer 9 has a spectral response range. The blackbody temperature simulation spectrum of the elliptical divergent light beam L1 may be a continuous spectrum, and the blackbody temperature simulation spectrum is used to correspond to the spectral response range of the sensor of the pyrometer 9. The spectral range of the blackbody temperature simulation spectrum may be, for example, 550 nm to 1700 nm. When the spectral range of the blackbody temperature simulation spectrum may be 550 nm to 750 nm and the central wavelength of the spectrum may be 650 nm, the pyrometer 9 may simulate a blackbody temperature range of 1000 degrees Celsius to 3000 degrees Celsius. When the spectrum range of the black body temperature simulation spectrum is 780 nm to 1150 nm and the center wavelength of the spectrum is 900 nm, the pyrometer 9 can simulate the black body temperature range of 300 degrees Celsius to 2000 degrees Celsius. When the spectrum range of the black body temperature simulation spectrum is 1500 nm to 1700 nm and the center wavelength of the spectrum is 1600 nm, the pyrometer 9 can simulate the black body temperature range of 200 degrees Celsius to 2000 degrees Celsius. The pyrometer 9 can have a filter to limit the sensing range of the sensor. Furthermore, the type of light source 20 used in the portable pyrometer calibration device 1 can be determined according to the spectral range limited by the filter (or coating) in the pyrometer 9. For example, the operator can first measure the spectral range of the filter (or coating) in the pyrometer 9 to be calibrated on site, and then select the portable pyrometer calibration device 1 with a light source 20 having a corresponding blackbody temperature simulation spectrum according to the measured spectral range. However, the present invention is not limited to the above spectral range.

The thermoelectric cooler (TEC) is in thermal contact with the light source 20 to dissipate heat from the light source 20. For example, the light source controller is electrically connected to the light source 20 and the thermoelectric cooler, and the thermoelectric cooler is used to dissipate heat from the light source 20 through the control of the light source controller.

In this embodiment, the light source controller adjusts the elliptical divergent light beam L1 to respond within the range of the blackbody temperature simulation spectrum according to the driving current of the light source 20 and the operating temperature of the light source 20. The operating temperature of the light source 20 can be controlled by a thermoelectric cooler. Specifically, the light source controller can adjust the light intensity of the light source 20 by controlling the driving current input to the light source 20. In addition, the light source controller can control the operating temperature of the light source 20 through the thermoelectric cooler to cause the spectrum of the light source 20 to redshift. In this way, the light beam output by the light source 20 can be controlled to have the desired blackbody temperature simulation spectrum range.

The beam adjustment structure 21 is disposed at a relative position corresponding to the light source 20 to collimate and transform the elliptical divergent light beam L1 into a circular parallel light beam L3. In detail, the beam adjustment structure 21 may include a collimator lens group 211 and a deformer lens group 212, the collimator lens group 211 is located between the light source 20 and the deformer lens group 212, and the central axis CL2 of the light source 20 is aligned with the optical axis CL1 of the collimator lens group 211. The collimator lens group 211 is used to collimate the elliptical divergent light beam L1 into an elliptical collimated light beam L2, and the deformer lens group 212 is used to transform the elliptical collimated light beam L2 into a circular parallel light beam L3. Among them, the deformable lens group 212 is a unidirectional beam expansion deformable prism group, and the deformable lens group 212 has a unidirectional magnification of 4X or more, but the present invention is not limited thereto. In other embodiments, the unidirectional magnification of the deformable lens group can be 2X to 6X. The elliptical divergent beam refers to a beam whose cross-sectional shape is elliptical and gradually diverges in the direction of travel; the elliptical collimated beam refers to a beam whose cross-sectional shape is elliptical and is a parallel beam or close to a parallel beam; the circular parallel beam refers to a beam whose cross-sectional shape is circular or close to a circular and is a parallel beam or close to a parallel beam. The circular parallel beam closes to a parallel beam, which may refer to a circular parallel beam having a divergence angle (divergence angle) less than or equal to the allowable light collection angle range of the pyrometer 9.

The collimator lens set 211 may include a first cylindrical lens E11 and a second cylindrical lens E12. The first cylindrical lens E11 is arranged in the X-axis direction to collimate the elliptical divergence light beam L1 and is closer to the light source 20 than the second cylindrical lens E12. The second cylindrical lens E12 is arranged in the Y-axis direction to collimate the elliptical divergence light beam L1. The focal length of the first cylindrical lens E11 may be 4.5 mm, and the focal length of the second cylindrical lens E12 may be 15 mm.

The deformable lens assembly 212 may include a first deformable prism E21 and a second deformable prism E22, and the first deformable prism E21 is closer to the collimating lens assembly 211 than the second deformable prism E22. The first deformable prism E21 and the second deformable prism E22 are arranged in the Y-axis direction to bend and expand the elliptical collimated light beam L2 into a circular parallel light beam L3.

Specifically, the first deformable prism E21 has a first incident surface S1 and a first exit surface S2 opposite to each other, and the angle θ1 between the first incident surface S1 and the first exit surface S2 is a sharp angle. The second deformable prism E22 has a second incident surface S3 and a second exit surface S4 opposite to each other, and the angle θ2 between the second incident surface S3 and the second exit surface S4 is a sharp angle. The elliptical collimated light beam L2 is incident on the first incident surface S1 at a polarizing angle (Brewster’s angle) and is vertically emitted from the first exit surface S2, and then is incident on the second incident surface S3 at a polarizing angle and is vertically emitted from the second exit surface S4, thereby forming a circular parallel light beam L3. The polarizing angle refers to the angle at which the reflected light and the refracted light are perpendicular to each other when the incident light enters the interface.

By arranging the deformable prisms of the deformable lens assembly at different angles, different one-way magnifications can be provided. In the present embodiment, the angle θ3 between the first output surface S2 of the first deformable prism E21 and the reference line perpendicular to the optical axis CL1 of the collimating lens assembly 211 can be, for example, 34.1 degrees, and the angle θ4 between the second output surface S4 of the second deformable prism E22 and the reference line perpendicular to the optical axis CL1 of the collimating lens assembly 211 can be, for example, 2.1 degrees. By arranging the first deformable prism E21 and the second deformable prism E22 at such an angle relationship, the deformable lens assembly 212 can provide a one-way magnification of more than 4X. However, the present invention is not limited thereto. For example, in other embodiments, the blackbody simulator of the portable pyrometer calibration device may adopt different types of light sources, and by changing the setting angles of the first deformable prism and the second deformable prism to have different angles θ3 and θ4, the deformable prism may provide different unidirectional magnifications (e.g., 2X to 6X unidirectional magnifications) to respond to and appropriately expand the light beam emitted by the light source used. The range of the angle θ3 can be 20.6 degrees to 39.7 degrees, and the range of the angle θ4 can be -6.5 degrees to 4.0 degrees, wherein the range of the angle θ4 being a negative value means that under certain magnification configurations, the second output surface of the second deformable prism is tilted from the upper right to the lower left direction of FIG. 2 relative to the vertical reference line after rotation.

In this embodiment, the deformable lens set 212 may be, for example, a deformable lens set with a product model number of 47-244 from Edmund, but the present invention is not limited thereto.

The handheld docking unit 4 is used to dock with the pyrometer 9. The optical fiber light guide tube 3 has a light receiving end 31 and a light emitting end 32 opposite to each other, wherein the light receiving end 31 is connected to the black body simulator 2 and is used to receive the circular parallel light beam L3 from the light beam adjustment structure 21, and the light emitting end 32 is connected to the handheld docking unit 4 and is used to emit the circular parallel light beam L3. The handheld docking unit 4 may have a docking structure (not shown separately) for being mounted on the pyrometer 9 so that the light emitting end 32 of the optical fiber light guide tube 3 is aligned with the pyrometer 9.

The optical fiber light guide tube 3 may be composed of a flexible material, and the optical fiber light guide tube 3 may include a plurality of optical fiber bundles (not shown separately), wherein the surface of each optical fiber bundle has a reflective coating for reflecting the circular parallel light beam L3, and the reflectivity of the reflective coating is, for example, greater than 99.7%. In this way, the reflective coating can be prevented from absorbing too much light energy, so that the optical fiber light guide tube 3 can reduce the loss of light energy when transmitting the circular parallel light beam L3, and avoid heat absorption causing coating damage. The flexible material is, for example, a polymer material, a silicon material, a glass material, and a plastic material, but the present invention is not limited thereto. In addition, the material of the reflective coating may be, for example, gold or silver, but the present invention is not limited thereto.

Through the configuration of the beam adjustment structure 21 in the present embodiment, the divergence angle of the circular parallel beam L3 can be less than 1.6 degrees, and the diameter of the circular parallel beam L3 at the light output end 32 can be 0.8 mm to 14 mm. When the portable pyrometer calibration device 1 is used to calibrate the pyrometer 9, the light output end 32 of the optical fiber light guide 3 and the pyrometer 9 can be spaced 0.7 m to 1.0 m apart. In this way, it can be ensured that the divergence angle of the circular parallel beam L3 meets the light receiving angle range of the pyrometer 9 (for example, the divergence angle is less than or equal to twice the light input half angle of the various types of pyrometers 9 mentioned above). Specifically, the pyrometer 9 has different sensing fields at different sensing distances. Therefore, by controlling the diameter and divergence angle of the circular parallel light beam L3 and the distance between the light output end 32 of the optical fiber light guide 3 and the pyrometer 9, the area of the circular parallel light beam L3 can cover the sensing field of the pyrometer 9 and the ranges of the two can be similar, so as to effectively utilize the energy of the light source 20 and ensure the accuracy of the calibration of the pyrometer 9. For example, when the pyrometer 9 to be calibrated is a fluke endurance E1RL high temperature radiation thermometer, the diameter of the circular parallel light beam L3 at the light output end 32 of the portable pyrometer calibration device 1 can be 6 mm, and the circular parallel light beam L3 is focused to the sensing element through the lens group after entering the fluke endurance E1RL high temperature radiation thermometer, and the spot size on the sensing element is 0.2 mm in the X-direction and 0.1 mm in the X-direction. When the pyrometer 9 to be calibrated is a chino IR-FAS IR-FL5AH02 high temperature radiation thermometer, the diameter of the circular parallel light beam L3 at the light output end 32 in the portable pyrometer calibration device 1 can be 5 mm, and the circular parallel light beam L3 is focused to the sensing element through the lens group after entering the chino IR-FAS IR-FL5AH02 high temperature radiation thermometer, and the spot size on the sensing element is 0.2 mm in the X-direction and 0.1 mm in the X-direction. When the pyrometer 9 to be calibrated is a LP3/LP4 series high temperature radiation thermometer of the German KE company, the diameter of the circular parallel light beam L3 at the light output end 32 in the portable pyrometer calibration device 1 can be 0.8 mm. When the pyrometer 9 to be calibrated is the MR1SASF high temperature radiation thermometer produced by Raytek Corporation of the United States, the diameter of the circular parallel light beam L3 at the light output end 32 of the portable pyrometer calibration device 1 can be 14 mm.

As shown in FIG1 , when the portable pyrometer calibration device 1 of the present embodiment is used to calibrate the pyrometer 9, the handheld docking unit 4 is first docked to the pyrometer 9 so that the pyrometer 9 senses the blackbody temperature simulation spectrum of the elliptical divergent light beam L1. Then, the temperature reading output by the pyrometer 9 is compared with the simulated temperature of the blackbody simulator 2. In the case where the two do not match, the parameters of the pyrometer 9 are adjusted so that the temperature reading output by the pyrometer 9 matches the simulated temperature of the blackbody simulator 2, thereby completing the calibration of the pyrometer 9.

The present invention is not limited to the configuration of the beam adjustment structure 21 of the first embodiment described above. In other embodiments, the beam adjustment structure may be further configured with a lens group having other functions, and the optical elements such as lenses and/or prisms in these lens groups of the beam adjustment structure may have different structures and/or quantity configurations. For example, please refer to FIG. 4, which is a partial schematic diagram of the light source and beam adjustment structure of the black body simulator and the optical fiber light guide tube of the portable pyrometer calibration device according to the second embodiment of the present invention. The portable pyrometer calibration device of this embodiment (corresponding to FIG. 4) is similar to the portable pyrometer calibration device 1 of the aforementioned FIGS. 1 to 2, and the same reference numerals are used to represent the same components. The functions and effects of each component are the same as those described above, and will not be repeated here.

In the blackbody simulator of the portable pyrometer calibration device of this embodiment, the collimator set 211b of the beam adjustment structure 21b may include a circularly symmetric lens E11. The aperture value of the circularly symmetric lens E11 is 0.5, and the circularly symmetric lens E11 is arranged in the X-axis direction and in the Y-axis direction perpendicular to the X-axis direction to collimate the elliptical divergent beam L1 from the light source 20b into an elliptical collimated beam L2. Among them, the central axis CL2 of the light source 20b is aligned with the optical axis CL1 of the collimator set 211b.

The deformable lens assembly 212b of the beam adjustment structure 21b may include a first deformable prism E21 and a second deformable prism E22. The first deformable prism E21 and the second deformable prism E22 are arranged in the Y-axis direction, and the first deformable prism E21 is closer to the collimating lens assembly 211b than the second deformable prism E22, so as to fold and expand the elliptical collimated light beam L2 into a circular parallel light beam L3.

Specifically, the first deformable prism E21 has a sharp angle θ1 formed by the first incident surface S1 and the first exit surface S2, and the second deformable prism E22 has another sharp angle θ2 formed by the second incident surface S3 and the second exit surface S4. The elliptical collimated light beam L2 is transformed into a circular parallel light beam L3 through the sharp angle θ1 and the other sharp angle θ2.

By setting the deformable prisms of the deformable lens group at different angles, different one-way magnifications can be provided. In this embodiment, the angle θ3 between the first output surface S2 of the first deformable prism E21 and the reference line perpendicular to the optical axis CL1 of the collimating lens group 211b can be, for example, 34.8 degrees, and the angle θ4 between the second output surface S4 of the second deformable prism E22 and the reference line perpendicular to the optical axis CL1 of the collimating lens group 211b can be, for example, 2.3 degrees. By setting the first deformable prism E21 and the second deformable prism E22 at such an angle relationship, the deformable lens group 212b can provide a one-way magnification of more than 4.22X, but the present invention is not limited thereto.

In addition, in this embodiment, the beam adjustment structure 21b may further include a homogenizer group 213b to even out the brightness of the circular parallel beam L3, and the homogenizer group 213b is located between the deformable lens group 212b and the light receiving end 31b of the optical fiber light guide 3b. The homogenizer group 213b may be a lens group designed for homogenizing light based on the principle of Köhler illumination. Specifically, the homogenizer group 213b may include a plano-convex lens E33, and the plano-convex lens E33 has a positive focal length to collect and focus light. The effective focal length of the plano-convex lens E33 may be 150 mm.

In this embodiment, the circularly symmetrical lens E11 may be, for example, a circularly symmetrical lens with a product model number of 33-263 from Edmund, the deformable lens set 212b may be, for example, a deformable lens set with a product model number of 47-274 from Edmund, and the plano-convex lens E33 may be, for example, a plano-convex lens with a product model number of 67-541 from Edmund, but the present invention is not limited thereto.

The present invention is not limited to the configuration of the homogenizer group 213b of the beam adjustment structure 21b of the second embodiment described above. In other embodiments, the homogenizer group can be further configured with optical elements having other functions. For example, please refer to FIG. 5, which is a partial schematic diagram of the light source and beam adjustment structure of the black body simulator and the optical fiber light guide of the portable pyrometer calibration device described in the third embodiment of the present invention. The portable pyrometer calibration device of this embodiment (corresponding to FIG. 5) is similar to the portable pyrometer calibration device of FIG. 4, and the same reference numerals are used to represent the same components. The functions and effects of each component are the same as those described above, and will not be repeated here.

In the blackbody simulator of the portable pyrometer calibration device of this embodiment, the homogenizer group 213b of the beam adjustment structure 21b further includes a first microarray lens E31, and the first microarray lens E31 is located between the deformable lens group 212b and the plano-convex lens E33. The first microarray lens E31 can be used for beam homogenization and shaping, and its size can be 10 mm × 10 mm, and its array spacing can be 300 microns. Among them, the first microarray lens E31 can be, for example, a microarray lens with a product model of 64-476 of Edmund Company.

For another example, please refer to FIG6, which is a schematic diagram of the light source and beam adjustment structure of the black body simulator and the partial optical fiber light guide tube of the portable pyrometer calibration device according to the fourth embodiment of the present invention. The portable pyrometer calibration device of this embodiment (corresponding to FIG6) is similar to the portable pyrometer calibration device of FIG5, and the same reference numerals are used to represent the same components. The functions and effects of each component are the same as those described above, and will not be repeated here.

In the blackbody simulator of the portable pyrometer calibration device of the present embodiment, the homogenizer group 213b of the beam adjustment structure 21b further includes a second microarray lens E32, and the second microarray lens E32 is located between the first microarray lens E31 and the plano-convex lens E33. The second microarray lens E32 can be used for beam homogenization and shaping, and its size can be 10 mm × 10 mm, and its array spacing can be 300 microns. The second microarray lens E32 can be, for example, a microarray lens of Edmund product model 64-476.

For another example, please refer to FIG. 7, which is a schematic diagram of the light source and beam adjustment structure of the black body simulator and the optical fiber light guide of the portable pyrometer calibration device according to the fifth embodiment of the present invention. The portable pyrometer calibration device of this embodiment (corresponding to FIG. 7) is similar to the portable pyrometer calibration device of FIG. 6, and the same reference numerals are used to represent the same components. The functions and effects of each component are the same as those described above, and will not be repeated here.

In the black body simulator of the portable pyrometer calibration device of the present embodiment, the homogenizer group 213b of the beam adjustment structure 21b further includes a diffuser E34, and the diffuser E34 is used to control the diffusion angle of the light beam. According to the portable pyrometer calibration device 1 disclosed by the present invention, different diffusers E34 can be selected according to the different light intensities of the light source 20 used to control the diffraction diffusion angle. The diffuser E34 is located between the plano-convex lens E33 and the light receiving end 31b of the optical fiber light guide 3b, and the distance D1 between the diffuser E34 and the plano-convex lens E33 can be 150 mm to 300 mm. For example, the distance D1 between the diffuser E34 and the plano-convex lens E33 may be 150 mm, 200 mm, 250 mm or 300 mm.

For another example, please refer to FIG8, which is a schematic diagram of the light source and beam adjustment structure of the black body simulator and the partial optical fiber light guide tube of the portable pyrometer calibration device according to the sixth embodiment of the present invention. The portable pyrometer calibration device of this embodiment (corresponding to FIG8) is similar to the portable pyrometer calibration device of FIG4, and the same reference numerals are used to represent the same components. The functions and effects of each component are the same as those described above, and will not be repeated here.

Compared with the portable pyrometer calibration device of FIG. 4 , in the black body simulator of the portable pyrometer calibration device of the present embodiment, the homogenizer group 213b of the beam adjustment structure 21b further includes a diffuser E34, and the diffuser E34 is used to control the diffusion angle of the light beam. The diffuser E34 is located between the plano-convex lens E33 and the light receiving end 31b of the optical fiber light guide 3b, and the distance D1 between the diffuser E34 and the plano-convex lens E33 can be 150 mm.

According to the portable pyrometer calibration device of the above-mentioned embodiment, a blackbody temperature simulation spectrum for calibrating the pyrometer is generated through a blackbody simulator, which can be used as a stable calibration heat source, so that the portable pyrometer calibration device has the advantage of small size and can be used on site due to its portable design. In addition, the blackbody simulator uses low-power cold light, which can avoid the problem of high temperature hazards during the calibration process, and there is no need to regularly replace consumables, which can reduce carbon emissions. In addition, the light source of the blackbody simulator can be heated to a predetermined temperature in a short time, so that the portable pyrometer calibration device can be heated up in less than 10 minutes, which is conducive to rapid installation and calibration on site. Furthermore, the elliptical divergent beam of the light source is collimated and transformed into a circular parallel beam through the beam adjustment structure, which can provide a black body temperature simulation spectrum that meets the pyrometer's light receiving angle range, thereby effectively utilizing the light source energy. In addition, by docking the pyrometer with a handheld docking unit, the light output end of the fiber optic light guide can be easily aligned with the pyrometer.

Although the present invention is disclosed as above with the aforementioned preferred embodiment, it is not used to limit the present invention. Anyone familiar with similar techniques can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of patent protection of the present invention shall be subject to the scope of the patent application attached to this specification.

1: Portable pyrometer calibration device

2: Blackbody simulator

3: Fiber optic light guide tube

31: Light receiving end

32: Light output end

4: Handheld docking unit

9: Thermometer

Claims (20)

A portable pyrometer calibration device is used to calibrate a pyrometer. The pyrometer is used to sense a blackbody temperature simulation spectrum and output a temperature reading. The portable pyrometer calibration device includes: a handheld docking unit for docking with the pyrometer; a blackbody simulator for generating the blackbody temperature simulation spectrum. The blackbody temperature simulation spectrum corresponds to a spectrum range when a high-temperature blackbody furnace is heated to a blackbody temperature range. The blackbody simulator includes a cold light source to generate a blackbody temperature simulation spectrum. and a beam adjustment structure, the cold light source has an elliptical divergent beam and the elliptical divergent beam accompanies the black body temperature simulation spectrum, the beam adjustment structure is arranged at a relative position corresponding to the cold light source to collimate and transform the elliptical divergent beam into a circular parallel beam; and an optical fiber light guide tube guides the circular parallel beam and has a relative light receiving end and a light emitting end, the light receiving end is connected to the black body simulator, and the light emitting end is connected to the handheld docking unit. The portable pyrometer calibration device as described in claim 1, wherein the beam adjustment structure includes a collimator lens set and a deformable lens set, the collimator lens set is located between the cold light source and the deformable lens set to collimate the elliptical divergent beam into an elliptical collimated beam, the deformable lens set is a unidirectional beam expansion deformable prism set to deform the elliptical collimated beam into the circular parallel beam, and the deformable lens set has a unidirectional magnification of 2X to 6X. A portable pyrometer calibration device as described in claim 2, wherein the collimating lens set includes a first cylindrical lens and a second cylindrical lens, the first cylindrical lens is arranged in an X-axis direction to collimate the elliptical divergent light beam and is closer to the cold light source than the second cylindrical lens, and the second cylindrical lens is arranged in a Y-axis direction perpendicular to the X-axis direction to collimate the elliptical divergent light beam. The portable pyrometer calibration device as described in claim 2, wherein the deformable lens group is a deformable prism group with a unidirectional magnification of 4X or more, the deformable lens group includes a first deformable prism and a second deformable prism, the first deformable prism is closer to the collimating lens group than the second deformable prism, and the first deformable prism and the second deformable prism are arranged in a Y-axis direction to fold and expand the elliptical collimated light beam into the circular parallel light beam. The portable pyrometer calibration device as described in claim 4, wherein the first deformable prism has a first incident surface and a first exit surface opposite to each other, the angle between the first incident surface and the first exit surface is an acute angle, the second deformable prism has a second incident surface and a second exit surface opposite to each other, the angle between the second incident surface and the second exit surface is an acute angle, the elliptical collimated light beam is incident on the first incident surface at a polarizing angle and is vertically emitted from the first exit surface, and then is incident on the second incident surface at a polarizing angle and is vertically emitted from the second exit surface, thereby forming the circular parallel light beam. The portable pyrometer calibration device as described in claim 2, wherein the beam adjustment structure further comprises a homogenizing lens set, and the homogenizing lens set is located between the deformable lens set and the light receiving end of the optical fiber light guide tube to even out the brightness of the circular parallel beam. The portable pyrometer calibration device as described in claim 6, wherein the collimating lens set includes a circularly symmetric lens arranged in an X-axis direction and a Y-axis direction perpendicular to the X-axis direction to collimate the elliptical divergent light beam. The portable pyrometer calibration device as described in claim 6, wherein the deformable lens group is a deformable lens group with a one-way magnification of 4.22X or more, and the deformable lens group includes a first deformable prism and a second deformable prism, the first deformable prism and the second deformable prism are arranged in a Y-axis direction, and the first deformable prism is closer to the collimating lens group than the second deformable prism to fold and expand the elliptical collimated light beam into the circular parallel light beam. The portable pyrometer calibration device as described in claim 8, wherein the first deformable prism has an acute angle composed of a first incident surface and a first exit surface opposite to each other, and the second deformable prism has another acute angle composed of a second incident surface and a second exit surface opposite to each other, and the elliptical collimated light beam is transformed into the circular parallel light beam through the acute angle and the other acute angle. A portable pyrometer calibration device as described in claim 6, wherein the homogenizing lens assembly comprises a plano-convex lens. The portable pyrometer calibration device as described in claim 10, wherein the homogenizing lens assembly further comprises a first micro-array lens located between the deformable lens assembly and the plano-convex lens. The portable pyrometer calibration device as described in claim 11, wherein the homogenizing lens assembly further comprises a second microarray lens located between the first microarray lens and the plano-convex lens. A portable pyrometer calibration device as described in claim 10 or claim 12, wherein the homogenizing lens assembly further comprises a diffuser located between the plano-convex lens and the light receiving end of the optical fiber light guide. A portable pyrometer calibration device as described in claim 2, wherein the central axis of the cold light source is aligned with the optical axis of the collimating lens assembly. The portable pyrometer calibration device as described in claim 1, wherein the black body simulator further comprises a light source controller electrically connected to the cold light source, and adjusts the elliptical divergent light beam to respond within the range of the black body temperature simulation spectrum according to the driving current of the cold light source and the operating temperature of the cold light source. The portable pyrometer calibration device as described in claim 1, wherein the black body simulator further comprises a thermoelectric cooler electrically connected to the light source controller and in thermal contact with the cold light source. The portable pyrometer calibration device as described in claim 1, wherein the cold light source is a broadband ultra-bright solid-state light source, an LED light source, a laser diode light source or a multi-wavelength light source. A portable pyrometer calibration device as described in claim 1, wherein a sensor in the pyrometer has a spectral response range, the blackbody temperature simulation spectrum is a continuous spectrum, the blackbody temperature simulation spectrum corresponds to the spectral response range, and the spectral range of the blackbody temperature simulation spectrum is 550 nanometers to 1700 nanometers. The portable pyrometer calibration device as described in claim 1, wherein the optical fiber light guide tube is composed of a flexible material and includes a plurality of optical fiber bundles, and the surface of each optical fiber bundle has a reflective coating. A portable pyrometer calibration device as described in claim 1, wherein the handheld docking unit has a docking structure that is mounted on the pyrometer to align the light-emitting end of the optical fiber light guide with the pyrometer.

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