Abstract

Determination of the reflectance for directional irradiation of diffusely reflecting samples requires measurement of the radiation reflected into the whole hemisphere. This can be done with integrating spheres. An arrangement based on a rapid-scan Fourier transform spectrometer equipped with a gold-coated integrating sphere allows measurement of the spectral reflectance in the 1.5μm–∼15μm wavelength range. Problems of calibration and accuracy are discussed. Results are compared with those of conventional techniques: measurement of the directional emittance of heated samples and measurement of the specular reflectance.

© 1985 Optical Society of America

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