대표
청구항
▼
1. A method for measuring spectral characteristics of materials comprising: providing a sample material and a heater that both include a spectrally flat, highly emissive surface portion;in one or both of an emissive configuration, in which the sample material is in thermal contact with the heater, and a transmissive configuration, in which the sample material is separated from the heater, capturing spectral-spatial data that includes radiance measurements over the spectrally flat, highly emissive surface portions, the spectral-spatial data being captured...
1. A method for measuring spectral characteristics of materials comprising: providing a sample material and a heater that both include a spectrally flat, highly emissive surface portion;in one or both of an emissive configuration, in which the sample material is in thermal contact with the heater, and a transmissive configuration, in which the sample material is separated from the heater, capturing spectral-spatial data that includes radiance measurements over the spectrally flat, highly emissive surface portions, the spectral-spatial data being captured at least two different heater temperatures for each of the configurations;determining temperatures of the sample material and heater at the different heater temperatures for each of the configurations using, in each instance, the radiance measurements taken over the sample material and the heater after the temperatures of both the heater and the sample material have stabilized;if the temperatures were determined for the transmissive configuration, determining the transmissivity of the sample material using the temperatures of the sample material and heater in the transmissive configuration and the spectral-spatial data collected at selected points of interest over the sample material; anddetermining the emissivity of the sample material using the temperatures of the sample material and heater in the emissive configuration, the spectral-spatial data collected at selected points of interest over the sample material, and the transmissivity of the sample material. 2. The method for measuring spectral characteristics of materials of claim 1, wherein the spectral-spatial data is captured in two or more spectral bands that include mid- or long-wave infrared bands. 3. The method for measuring spectral characteristics of materials of claim 1, wherein the spectral-spatial data is captured by a sensor at a distance of approximately one meter or less from the sample material. 4. The method for measuring spectral characteristics of materials of claim 1, further comprising: determining the reflectivity of the sample material using the emissivity and the transmissivity. 5. The method for measuring spectral characteristics of materials of claim 1, wherein the spectral-spatial data includes radiance measurements taken over thermal calibration sources. 6. The method for measuring spectral characteristics of materials of claim 5, further comprising: performing radiometric calibration of the spectral-spatial data using the radiance measurements taken over thermal calibration sources to generate radiometrically calibrated data. 7. The method for measuring spectral characteristics of materials of claim 6, wherein the radiometric calibration is performed prior to determining the temperatures of the sample material and heater. 8. The method for measuring spectral characteristics of materials of claim 1, wherein the sample material and the heater each include a spectrally flat, highly emissive surface portion over which the radiance measurements are taken over the sample material and the heater, respectively. 9. The method for measuring spectral characteristics of materials of claim 1, further comprising: using a non-contact thermometer to determine when the temperature of the sample material has stabilized. 10. The method for measuring spectral characteristics of materials of claim 1, wherein the temperatures of the sample material and heater are determined from the radiance measurements by utilizing Planck's equation. 11. A method for measuring spectral characteristics of materials comprising: providing a thermal imaging device that is configured to capture spectral-spatial data and to be repositionable in relation to a sample holder and first and second thermal calibration sources;setting the first and second thermal calibration sources to first and second calibration temperatures, respectively;providing a sample material and a heater each with a spectrally flat, highly emissive surface portion;placing the sample material in the holder and in thermal contact with the heater, in an emissive configuration, such that the thermal imaging device has an unobstructed view of the spectrally flat, highly emissive surface portions when the thermal imaging device is in at least one imaging position;sequentially setting the heater to a plurality of emissive configuration heater temperatures and, for each of the emissive configuration heater temperatures, after the temperatures of both the heater and the sample material have stabilized repositioning the imaging device in relation to the sample material, the heater, and the first and second thermal calibration sources, andusing the thermal imaging device to capture data that includes radiance measurements;performing radiometric calibration of the data using the radiance measurements taken over the first and second thermal calibration sources to generate radiometrically calibrated data;determining emissive configuration temperatures of the sample material and heater, after the temperature of the heater has stabilized at each of the emissive configuration heater temperatures, respectively, using the radiance measurements taken over the sample material and the heater; anddetermining the emissivity of the sample material using the emissive configuration temperatures of the sample material and heater and the radiometrically calibrated data collected at selected points of interest over the sample material. 12. The method for measuring spectral characteristics of materials of claim 11, wherein the thermal imaging device is an imaging spectrograph that measures thermal radiance in two or more spectral bands. 13. The method for measuring spectral characteristics of materials of claim 12, wherein the two or more spectral bands include mid- or long-wave infrared bands. 14. The method for measuring spectral characteristics of materials of claim 11, wherein the thermal imaging device includes multispectral or hyperspectral sensors. 15. The method for measuring spectral characteristics of materials of claim 11, wherein the thermal imaging device includes an array of sensing devices. 16. The method for measuring spectral characteristics of materials of claim 11, wherein the thermal imaging device includes a sensor that is approximately one meter or less in distance from the sample material when the thermal imaging device is in the at least one imaging position. 17. The method for measuring spectral characteristics of materials of claim 11, wherein the thermal imaging device is provided with optics for changing the focus of the thermal imaging device. 18. The method for measuring spectral characteristics of materials of claim 11, wherein the first and second calibration temperatures are both above ambient temperature. 19. The method for measuring spectral characteristics of materials of claim 11, wherein the first and second calibration temperatures are approximately 30° C. and approximately 50° C., respectively. 20. The method for measuring spectral characteristics of materials of claim 11, wherein the spectrally flat, highly emissive surface portion of the sample material is approximately 1.5 cm in diameter. 21. The method for measuring spectral characteristics of materials of claim 11, wherein the spectrally flat, highly emissive surface portion of the sample material is a coating applied directly or indirectly to the sample material. 22. The method for measuring spectral characteristics of materials of claim 11, wherein the emissive configuration heater temperatures include a lowest set point which is approximately 5° C. above ambient temperature. 23. The method for measuring spectral characteristics of materials of claim 11, further comprising: using a non-contact thermometer to determine when the temperature of the sample material has stabilized. 24. The method for measuring spectral characteristics of materials of claim 11, wherein the temperatures of the sample material and heater are determined from the radiance measurements by utilizing Planck's equation. 25. The method for measuring spectral characteristics of materials of claim 11, wherein determining the emissivity of the sample material includes determining the transmissivity of the sample material. 26. The method for measuring spectral characteristics of materials of claim 25, wherein determining the transmissivity of the sample material includes: repositioning the heater in relation to the sample material such that the sample material is separated from the heater, in a transmissive configuration, and such that the thermal imaging device has an unobstructed view of the spectrally flat, highly emissive surface portions when the thermal imaging device is in at least one imaging position;sequentially setting the heater to a plurality of transmissive configuration heater temperatures and, for each of the emissive configuration heater temperatures, after the temperatures of both the heater and the sample material have stabilized repositioning the imaging device in relation to the sample material, the heater, and the first and second thermal calibration sources, andusing the thermal imaging device to add additional radiance measurements to the data;determining transmissive configuration temperatures of the sample material and heater, after the temperature of the heater has stabilized at each of the transmissive configuration heater temperatures, respectively, using the radiance measurements taken over the sample material and the heater in the transmissive configuration; anddetermining the transmissivity of the sample material using the transmissive configuration temperatures of the sample material and heater and the radiometrically calibrated data collected at selected points of interest over the sample material. 27. The method for measuring spectral characteristics of materials of claim 25, further comprising: using the emissivity and the transmissivity to determine the reflectivity of the sample material. 28. A method for measuring spectral characteristics of materials comprising: providing a thermal imaging device that is configured to capture spectral-spatial data and to be repositionable in relation to a sample material and first and second thermal calibration sources;setting the first and second thermal calibration sources to first and second calibration temperatures, respectively;providing a sample material and a heater each with a spectrally flat, highly emissive surface portion;placing the sample material in thermal contact with the heater, in an emissive configuration, such that the thermal imaging device has an unobstructed view of the spectrally flat, highly emissive surface portions when the thermal imaging device is in at least one imaging position;sequentially setting the heater to a plurality of emissive configuration heater temperatures and, for each of the emissive configuration heater temperatures, after the temperatures of both the heater and the sample material have stabilized repositioning the imaging device in relation to the sample material, the heater, and the first and second thermal calibration sources, andusing the thermal imaging device to capture data that includes radiance measurements;repositioning the heater in relation to the sample material such that the sample material is separated from the heater, in a transmissive configuration, and such that the thermal imaging device has an unobstructed view of the spectrally flat, highly emissive surface portions when the thermal imaging device is in at least one imaging position;sequentially setting the heater to a plurality of transmissive configuration heater temperatures and, for each of the emissive configuration heater temperatures, after the temperatures of both the heater and the sample material have stabilized repositioning the imaging device in relation to the sample material, the heater, and the first and second thermal calibration sources, andusing the thermal imaging device to add additional radiance measurements to the data;performing radiometric calibration of the data using the radiance measurements taken over the first and second thermal calibration sources to generate radiometrically calibrated data;determining transmissive configuration temperatures of the sample material and heater, after the temperature of the heater has stabilized at each of the transmissive configuration heater temperatures, respectively, using the radiance measurements taken over the sample material and the heater in the transmissive configuration;determining emissive configuration temperatures of the sample material and heater, after the temperature of the heater has stabilized at each of the emissive configuration heater temperatures, respectively, using the radiance measurements taken over the sample material and the heater in the emissive configuration;determining the transmissivity of the sample material using the transmissive configuration temperatures of the sample material and heater and the radiometrically calibrated data collected at selected points of interest over the sample material; anddetermining the emissivity of the sample material using the emissive configuration temperatures of the sample material and heater, the radiometrically calibrated data collected at selected points of interest over the sample material, and the transmissivity of the sample material. 29. The method for measuring spectral characteristics of materials of claim 28, wherein the thermal imaging device is an imaging spectrograph that measures thermal radiance in two or more spectral bands. 30. The method for measuring spectral characteristics of materials of claim 29, wherein the two or more spectral bands include mid- or long-wave infrared bands. 31. The method for measuring spectral characteristics of materials of claim 28, wherein the thermal imaging device includes multispectral or hyperspectral sensors. 32. The method for measuring spectral characteristics of materials of claim 28, wherein the thermal imaging device includes an array of sensing devices. 33. The method for measuring spectral characteristics of materials of claim 28, wherein the thermal imaging device includes a sensor that is approximately one meter or less in distance from the sample material when the thermal imaging device is in the at least one imaging position. 34. The method for measuring spectral characteristics of materials of claim 28, wherein the thermal imaging device is provided with optics for changing the focus of the thermal imaging device. 35. The method for measuring spectral characteristics of materials of claim 28, wherein the first and second calibration temperatures are both above ambient temperature. 36. The method for measuring spectral characteristics of materials of claim 28, wherein the first and second calibration temperatures are approximately 30° C. and approximately 50° C., respectively. 37. The method for measuring spectral characteristics of materials of claim 28, wherein the spectrally flat, highly emissive surface portion of the sample material is approximately 1.5 cm in diameter. 38. The method for measuring spectral characteristics of materials of claim 28, wherein the spectrally flat, highly emissive surface portion of the sample material is a coating applied directly or indirectly to the sample material. 39. The method for measuring spectral characteristics of materials of claim 28, wherein the heater temperatures include a lowest set point which is approximately 5° C. above ambient temperature. 40. The method for measuring spectral characteristics of materials of claim 28, wherein the emissive configuration heater temperatures and the transmissive configuration heater temperatures are the same sequence of temperatures. 41. The method for measuring spectral characteristics of materials of claim 28, wherein the heater, in the transmissive configuration, is separated from the sample material by a distance of approximately 4 cm. 42. The method for measuring spectral characteristics of materials of claim 28, further comprising: using a non-contact thermometer to determine when the temperature of the sample material has stabilized. 43. The method for measuring spectral characteristics of materials of claim 28, the temperatures of the sample material and heater are determined from the radiance measurements by utilizing Planck's equation. 44. The method for measuring spectral characteristics of materials of claim 28, further comprising: using the emissivity and the transmissivity to determine the reflectivity of the sample material. 45. A system for measuring spectral characteristics of materials comprising: a thermal imaging device that is configured to capture spectral-spatial data;a repositioning device configured to reposition the thermal imaging device in relation to a sample holder and first and second thermal calibration sources;a heater mechanically coupled to the sample holder such that the heater can be selectively moved between an emissive configuration, in which the heater is in thermal contact with a sample material attached to the holder, and a transmissive configuration, in which the heater is separated from the sample material; anda controller configured to generate control signals that are provided to the thermal imaging device, the repositioning device, the first and second thermal calibration sources, and the heater to set the first and second thermal calibration sources to first and second calibration temperatures, respectively,sequentially set the heater to a plurality of emissive configuration heater temperatures, when the heater is in the emissive configuration,sequentially set the heater to a plurality of transmissive configuration heater temperatures, when the heater is in the transmissive configuration,reposition the thermal imaging device in relation to the sample material, the heater, and the first and second thermal calibration sources,use the thermal imaging device to capture data that includes radiance measurements taken over the sample material, the heater, and the first and second thermal calibration sources,perform radiometric calibration of the data using the radiance measurements taken over the first and second thermal calibration sources to generate radiometrically calibrated data,for semi-transparent sample materials, determine transmissive configuration temperatures of the sample material and heater, after the temperature of the heater has stabilized at each of the transmissive configuration heater temperatures, respectively, using the radiance measurements taken over the sample material and the heater in the transmissive configuration,determine emissive configuration temperatures of the sample material and heater, after the temperature of the heater has stabilized at each of the emissive configuration heater temperatures, respectively, using the radiance measurements taken over the sample material and the heater in the emissive configuration,for semi-transparent sample materials, determine the transmissivity of the sample material using the transmissive configuration temperatures of the sample material and heater and the radiometrically calibrated data collected at selected points of interest over the sample material,determine the emissivity of the sample material using the emissive configuration temperatures of the sample material and heater, the radiometrically calibrated data collected at selected points of interest over the sample material, and, for semi-transparent sample materials, the transmissivity of the sample material, anddetermine the reflectivity of the sample material using the emissivity and, for semi-transparent sample materials, the transmissivity. 46. The system for measuring spectral characteristics of materials of claim 45, wherein the thermal imaging device is an imaging spectrograph that measures thermal radiance in two or more spectral bands. 47. The system for measuring spectral characteristics of materials of claim 46, wherein the two or more spectral bands include mid- or long-wave infrared bands. 48. The system for measuring spectral characteristics of materials of claim 45, wherein the thermal imaging device includes multispectral or hyperspectral sensors. 49. The system for measuring spectral characteristics of materials of claim 45, wherein the thermal imaging device includes an array of sensing devices. 50. The system for measuring spectral characteristics of materials of claim 45, wherein the thermal imaging device includes a sensor that is approximately one meter or less in distance from the sample material when the thermal imaging device is in at least one imaging position of the thermal imaging device. 51. The system for measuring spectral characteristics of materials of claim 45, wherein the thermal imaging device is provided with optics for changing the focus of the thermal imaging device. 52. The system for measuring spectral characteristics of materials of claim 45, wherein the first and second calibration temperatures are both above ambient temperature. 53. The system for measuring spectral characteristics of materials of claim 45, wherein the first and second calibration temperatures are approximately 30° C. and approximately 50° C., respectively. 54. The system for measuring spectral characteristics of materials of claim 45, wherein the sample material and the heater each include a spectrally flat, highly emissive surface portion over which the radiance measurements are taken over the sample material and the heater, respectively. 55. The system for measuring spectral characteristics of materials of claim 45, wherein the heater temperatures include a lowest set point which is approximately 5° C. above ambient temperature. 56. The system for measuring spectral characteristics of materials of claim 45, wherein the emissive configuration heater temperatures and the transmissive configuration heater temperatures are the same sequence of temperatures. 57. The system for measuring spectral characteristics of materials of claim 45, wherein the heater, in the transmissive configuration, is separated from the sample material by a distance of approximately 4 cm. 58. The system for measuring spectral characteristics of materials of claim 45, wherein the temperatures of the sample material and heater are determined from the radiance measurements by utilizing Planck's equation.
