Semi-automatic laboratory goniospectrometer system for performing multi-angular reflectance and polarization...

Area of Science:

• Optics and Remote Sensing
• Materials Science
• Geophysics

Background:

• Understanding the scattering properties of natural surfaces is crucial for Earth observation and climate modeling.
• Accurate measurement of surface reflectance and polarization is essential for remote sensing applications.

Purpose of the Study:

• To describe the design and operation of the Northeast Normal University Laboratory Goniospectrometer System.
• To demonstrate the system's capability for multi-angular reflected and polarized measurements.
• To present initial measurements of natural surfaces using the developed system.

Main Methods:

• A semi-automatic arm on a rotated circular ring for full hemispherical Bidirectional Reflectance Factor (BRF) acquisition.
• Polarizing optics for linear polarization measurements across the 350 nm to 2300 nm spectrum.
• Calibration using a Spectralon plane to establish polarimetric accuracy.

Main Results:

• The goniospectrometer achieves an average uncertainty of 1% for BRF and less than 5% for linear polarization.
• Polarimetric accuracy is demonstrated to be below 0.01 in the degree of linear polarization.
• Reflectance and polarization data for snow, soil, sand, and ice were collected between 2010-2013.

Conclusions:

• The developed goniospectrometer system provides stable and accurate multi-angular measurements of surface reflectance and polarization.
• The collected data on natural surfaces contribute to a better understanding of Earth's surface scattering properties.
• This instrument is valuable for advancing research in remote sensing and Earth science.