Accordance of Light Scattering from Design and De-Facto Variants of a Daylight Redirecting Component

For the systematic development of a small-scale daylight-redirecting louver system the impact of manufacturing on light scattering characteristics has to be quantified, localized and understood. In this research, the accordance of the measured scattering distributions of a de-facto production sample V1 with the computed predictions based on its design geometry V2 are quantified for selected incident light directions. A metric describing the global accordance of distributions is adapted to quantify their overall difference. A novel metric of local accordance allows further analysis. A particular low global accordance between V1 and V2 is found for an incident elevation θ i = 35 ∘ . To test the hypothesis that this result can be explained by observed geometric deviations, a simulation model V3 replicating these is compared to the design. The hypothesis is supported by the resulting high degree of accordance. The low local accordance for individual outgoing light directions indicates geometric non-uniformity of the sample V1. This method has been found useful for product development and quality assurance. Beyond their application in the proposed method, global and local accordance have potential applications in all fields of light scattering measurements.

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