Optical reflection characteristic-based emissivity analysis of a pyramid array flat-plate blackbody for remote sensor...

Area of Science:

• Optics and Photonics
• Infrared Technology
• Radiometric Calibration

Background:

• Accurate radiometric calibration in infrared remote sensing relies on flat-plate blackbodies (FPBs).
• FPB emissivity is a critical parameter directly impacting calibration accuracy.
• Understanding reflection characteristics (specular, near-specular, diffuse) is key to optimizing FPB performance.

Purpose of the Study:

• To quantitatively analyze the emissivity of FPBs with pyramid array structures.
• To investigate the influence of different optical reflection characteristics on FPB emissivity.
• To validate simulation results with experimental measurements.

Main Methods:

• Emissivity simulations using the Monte Carlo method.
• Analysis of specular reflection (SR), near-specular reflection (NSR), and diffuse reflection (DR) effects.
• Experimental fabrication and testing of FPBs with NSR and DR.

Main Results:

• FPBs with NSR demonstrated high emissivity, reaching 0.996 in the 8-14 µm waveband.
• Emissivity uniformity was excellent, with variations better than 0.005 at positions and 0.002 at angles.
• Experimental results closely matched simulation predictions, with low uncertainties (0.47% for waveband emissivity, 0.38% for spectral emissivity).

Conclusions:

• Pyramid array structures enhance FPB emissivity, particularly with NSR.
• The study provides a validated method for simulating and measuring FPB emissivity.
• Achieved high emissivity and uniformity are critical for advancing infrared remote sensing accuracy.