Paper, board and pulps. Measurement of diffuse radiance factor

2015 ◽  
Keyword(s):  
Radiance Factor

NPL scales for radiance factor and total diffuse reflectance

Metrologia ◽  
2003 ◽  
Vol 40 (1) ◽  
pp. S192-S195 ◽  
Author(s):  
C J Chunnilall ◽  
A J Deadman ◽  
L Crane ◽  
E Usadi
Keyword(s):  
Diffuse Reflectance ◽  
Radiance Factor

Measurement of Radiance Factor of Ground Target Using Triple-Band Optical Imaging System

2014 ◽  
Vol 34 (6) ◽  
pp. 0612003
Author(s):  
郭帮辉 Guo Banghui ◽  
黄剑波 Huang Jianbo ◽  
刘建卓 Liu Jianzhuo ◽  
王健 Wang Jian ◽  
孙强 Sun Qiang
Keyword(s):  
Optical Imaging ◽  
Imaging System ◽  
Ground Target ◽  
Optical Imaging System ◽  
Radiance Factor ◽  
Triple Band

scholarly journals Data processing and interpretation of sea radiance factor measurements

1994 ◽  
Vol 13 (1) ◽  
pp. 3-12 ◽  
Author(s):  
Helgi Arst ◽  
Tut Kutser
Keyword(s):  
Data Processing ◽  
Radiance Factor

scholarly journals Multilateral spectral radiance factor scale comparison

2017 ◽  
Vol 56 (7) ◽  
pp. 1996 ◽  
Author(s):  
C. Strothkämper ◽  
A. Ferrero ◽  
A. Koo ◽  
P. Jaanson ◽  
G. Ged ◽  
...  
Keyword(s):  
Spectral Radiance ◽  
Radiance Factor

scholarly journals Fluorescence model for multi-layer papers using conventional spectrophotometers

2012 ◽  
Vol 27 (2) ◽  
pp. 418-425 ◽  
Author(s):  
Ludovic Gustafsson Coppel ◽  
Mattias Andersson ◽  
Magnus Neuman ◽  
Per Edström
Keyword(s):  
Quantum Efficiency ◽  
Spectral Radiance ◽  
Electromagnetic Spectrum ◽  
Optical Parameters ◽  
Fluorescent Whitening Agent ◽  
Whitening Agent ◽  
Visible Part ◽  
Fluorescence Characteristics ◽  
Apparent Quantum Efficiency ◽  
Radiance Factor

Abstract We present an extension of a Kubelka- Munk based fluorescence model in which we introduce an apparent scattering (SUV) and absorption (KUV) coefficient for all wavelengths below 400 nm. We describe a method for modelling the total radiance factor of multi-layer papers and for estimating the optical parameters (S, K and Q) of each layer. Assuming that the fluorescent whitening agent only absorbs below 400 nm, we are able to determine SUV, KUVand the apparent quantum efficiency, Q(UV,λ) for 400 nm<λ<700 nm, from spectral radiance measurements in the visual part of the electromagnetic spectrum. We test the proposed method on different layered constructions made of three individual pilot paper layers. The proposed method allows the papermaker to determine the illumination independent fluorescence characteristics of single- and multilayer paper layers using a conventional singlemonochromator spectrophotometer operating in the visible part of the electromagnetic spectrum, and also to predict the radiance factor of fluorescing layered papers.

scholarly journals The surface of (4) Vesta in visible light as seen by Dawn/VIR

2021 ◽  
Vol 653 ◽  
pp. A118
Author(s):  
B. Rousseau ◽  
M. C. De Sanctis ◽  
A. Raponi ◽  
M. Ciarniello ◽  
E. Ammannito ◽  
...  
Keyword(s):  
Impact Craters ◽  
The Other ◽  
Upper Crust ◽  
Entire Surface ◽  
Spectral Parameters ◽  
Band Center ◽  
Band Area ◽  
Radiance Factor ◽  
Visible Wavelengths ◽  
Peculiar Behavior

Aims. We analyzed the surface of Vesta at visible wavelengths, using the data of the Visible and InfraRed mapping spectrometer (VIR) on board the Dawn spacecraft. We mapped the variations of various spectral parameters on the entire surface of the asteroid, and also derived a map of the lithology. Methods. We took advantage of the recent corrected VIR visible data to map the radiance factor at 550 nm, three color composites, two spectral slopes, and a band area parameter relative to the 930 nm crystal field signature in pyroxene. Using the howardite-eucrite-diogenite meteorites data as a reference, we derived the lithology of Vesta using the variations of the 930 and 506 nm (spin-forbidden) band centers observed in the VIR dataset. Results. Our spectral parameters highlight a significant spectral diversity at the surface of Vesta. This diversity is mainly evidenced by impact craters and illustrates the heterogeneous subsurface and upper crust of Vesta. Impact craters also participate directly in this spectral diversity by bringing dark exogenous material to an almost entire hemisphere. Our derived lithology agrees with previous results obtained using a combination of infrared and visible data. We therefore demonstrate that it is possible to obtain crucial mineralogical information from visible wavelengths alone. In addition to the 506 nm band, we identified the 550 nm spin-forbidden one. As reported by a laboratory study for synthetic pyroxenes, we also do not observe any shift of the band center of this feature across the surface of Vesta, and thus across different mineralogies, preventing use of the 550 nm spin-forbidden band for the lithology derivation. Finally, the largest previously identified olivine rich-spot shows a peculiar behavior in two color composites but not in the other spectral parameters.

scholarly journals Methods Calculating the Slab Radiance Factor

2020 ◽  
pp. paper16-1-paper16-13
Author(s):  
Vladimir Budak ◽  
Dmitry Efremenko
Keyword(s):  
High Speed ◽  
Radiation Transport ◽  
Complete Solution ◽  
Light Reflection ◽  
Approximate Methods ◽  
Transfer Theory ◽  
Long Time ◽  
Critical Problems ◽  
Reflection Of Light ◽  
Radiance Factor

One of the most critical problems of realistic visualization of the real-world objects is physically adequate modeling of their reflection of light. Reflection of light by objects occurs both from the surface and the bulk of matter (scattering). Accounting for the light reflection from the surface of objects was solved almost a century ago based on its representation as a Fresnel randomly rough surface. Scattering by a bulk of matter is the subject of radiation transfer theory, which has only recently received its known completion in the form of discrete transfer theory. Strict analytical methods for solving the radiation transport equation (RTE) are often not highly effective for calculating the radiance factor. For a long time, in the absence of effective numerical methods for solving problems and the unavailability of high-speed computers for practical calculations, approximate methods for solving RTE were developed. However, their accuracy and applicability limits were poorly defined. The discrete transfer theory allowed us to evaluate the existing approximate methods for solving the UPI, their accuracy, and the efficiency of application for calculating the radiance factor. It is shown that the most effective method is the method of synthetic iterations. The method is based on the selection of the solution anisotropic part based on a small-angle approximation of the RTE solution. The solution regular part can be calculated by any approximation. Then a simple iteration from the complete solution is performed to refine the angular distribution of the radiance factor.

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