Bidirectional reflectance capabilities of the NIST Robotic Optical Scattering Instrument (ROSI)

A simple, laser-based reflectometer is described for the measurement of water turbidity via 180° optical scattering. Applications exist both in clean source waters (0-1000NTU) with a minimum detectable turbidity better than 1NTU, and in dense wastewater primary-clarifier sludges. The non-contact measurement is performed from a distance at least up to 10m, substantially avoiding the usual window fouling problems of optical instruments. By measuring directly in the process, through a free water surface or on the side of a flowing water stream, the difficulties of transporting sample to the instrument are also avoided. Extensions to be described allow measurement also of water colour.

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Retrieval of Particle Size of Natural Granite From Multiangular Bidirectional Reflectance Spectra Using the Hapke Model (June 2020)

IEEE Transactions on Geoscience and Remote Sensing ◽

10.1109/tgrs.2020.3030101 ◽

2020 ◽

pp. 1-12

Author(s):

Mengjuan Wu ◽

Jinlin Wang ◽

Quan Wang ◽

Kefa Zhou ◽

Zhixin Zhang ◽

...

Keyword(s):

Particle Size ◽

Reflectance Spectra ◽

Bidirectional Reflectance

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Void Engineering in Silica Glass for Ultralow Optical Scattering Loss

Journal of Lightwave Technology ◽

10.1109/jlt.2021.3089171 ◽

2021 ◽

pp. 1-1

Author(s):

Madoka Ono

Keyword(s):

Silica Glass ◽

Optical Scattering ◽

Scattering Loss

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One-shot BRDF imaging system to obtain surface properties

Optical Review ◽

10.1007/s10043-021-00689-x ◽

2021 ◽

Author(s):

Hiroshi Ohno ◽

Takahiro Kamikawa

Keyword(s):

Surface Properties ◽

Imaging System ◽

Reconstruction Method ◽

Surface Reflectance ◽

Bidirectional Reflectance Distribution Function ◽

Bidirectional Reflectance ◽

Color Mapping ◽

System A ◽

Cone Surface ◽

Bidirectional Reflectance Distribution

AbstractThe bidirectional reflectance distribution function (BRDF) that describes an angle-resolved distribution of surface reflectance is available for characterizing surface properties of a material. A one-shot BRDF imaging system can capture an in-plane color mapping of light direction extracted from a surface BRDF distribution. A surface roughness identification method is then proposed here using the imaging system. A difference between surface properties of a matt paper and a glossy paper is experimentally shown to be detected using the method. A surface reconstruction method of an axisymmetric micro-object using the imaging system is also proposed here. The imaging system experimentally shows that it can reconstruct an axisymmetric aluminium cone surface with a height of 37 μm.

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