| Author(s): |
Simon G. Kaplan; Leonard M. Hanssen; Enrique J. Iglesias; |
| Title: |
Angle-dependent infrared reflectance measurements in support of VIIRS |
| Published: |
August 14, 2008 |
| Abstract: |
We have developed a goniometric reflectometer using a Fourier-transform infrared (FTIR) spectrometer source for polarized reflectance measurements from 1 um to 20 um wavelength at angles of incidence from 10° to 80°, with an incident beam geometry of approximately f/25. Measurements are performed in either absolute mode, or relative to a reference mirror that has been calibrated at near-normal incidence using an integrating sphere-based reflectometer. Uncertainties in the 0.2 % to 0.5 % range are achieved using a photoconductive 77 K InSb detector from 1 um to 5 um and a 12 K Si:As BIB detector from 2 um to 20 um. The performance of the system has been tested using dielectric materials such as Si as well as high-quality Au mirrors. We describe measurements of SiOx-coated Ag mirrors similar to the half-angle mirror (HAM) used in the VIIRS optical scanning system. Various coatings are analyzed to help assess the effect of p-polarized absorption bands at angles from 10° to 65° and wavelengths between 3 um and 13 um. |
| Proceedings: |
SPIE Infrared Spaceborne Remote Sensing and Instrumentation XVI |
| Volume: |
7082 |
| Pages: |
pp. 1 - 10 |
| Location: |
San Diego, CA |
| Dates: |
August 10-14, 2008 |
| Keywords: |
infrared; optical coatings; polarization; radiometry; reflectance |
| Research Areas: |
Optics |
