31 December 1993 Methods of measuring brightness indicatrices of light-diffusing coating applied on spherical substrate
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Proceedings Volume 2161, CIS Selected Papers: Photometry; (1993) https://doi.org/10.1117/12.166395
Event: Photometry: Selected Papers from the 8th and 9th CIS Conferences, 1992, Moscow, Russian Federation
One of the basic optical characteristics, describing the light-diffusing properties of materials and coatings is a spatial indicatrix of reflection. When illuminating the studied sample of material from some fixed directions the reflection indicatrices are characterizing changes in the reflected flux intensity depending on angles of reflection. In this case the illumination direction for the materials and coating with isotropic surface properties is characterized by one, zenith angle €-j,counted off from the normal to a surface in the incidence plane (this plane contains the light incidence direction and normal to the sample surfaces) and the reflection direction -by two angles: a zenith angle e , counted off between the selected direction of reflection and the mentioned normal, as well as an azimuthal angle between the planes of incidence and reflection (the latter incorporates the reflection direction and normal to the sample surfaces) . Thus the devices usually referred to as goniophotometers, used for measuring the reflection indicatrices should have in accordance with the minimum number of measured function arguments, at least three degrees of freedom. allowing to change in respect to each other the relative angular positions of goniophotometer elements: the illuminant, sample and photometer (an instrument measuring the luminous intensity or the sample brightness in specified directions) . The stated three degrees of freedom are realized in the known designs of goniophotometers by various mechanical constructions with the use of a flat sample.
© (1993) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
M. V. Tantashev, M. V. Tantashev, G. K. Kholopov, G. K. Kholopov, } "Methods of measuring brightness indicatrices of light-diffusing coating applied on spherical substrate", Proc. SPIE 2161, CIS Selected Papers: Photometry, (31 December 1993); doi: 10.1117/12.166395; https://doi.org/10.1117/12.166395

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