Detector
§Light scattered from the
sample passes through a dichroic polarizer and is reflected 90 degrees by a front-surface folding mirror,
and is focused onto the detector slit
by a 120mm achromatic doublet lens.
§A spectroradiometer
serves as the detector; this contains a 1200 l/mm grating and acquires 1024 samples across the approximate range
385nm-710nm.
§The detector uses a diffraction grating to separate
wavelengths. We measure the BRDF twice
with polarizations 90 degrees apart, then use a weighted average to get the BRDF for a polarization-insensitive sensor.
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