Light guiding is used to direct light from an emitting source to a different location. It is frequently realized through a clad-core structure with a difference in the refractive index of the materials. This paper explores the possibility of combining a fluoropolymer (THV) film of low refractive index, serving as a cladding layer, with a polycarbonate (PC) core, via injection molding.
View Article and Find Full Text PDFWe discuss and describe the development of an origination process for planar free-form micro-optical elements from a given optical design. The targeted masters serve as origination structures for a roll-to-roll mass fabrication process. Specifically targeted are complex, optically smooth, surface relief structures with variable structure heights in the range of 1-20 µm, with typical lateral sizes of more than 5 µm.
View Article and Find Full Text PDFWe present an iterative optical and thermal simulation procedure which enables the determination of the temperature distribution in the phosphor layer of a phosphor converted LED with good accuracy. Using the simulation both the highest phosphor temperatures, which are mostly relevant to material degradation as well as the temperatures of those phosphor particles which mainly contribute to converted light emission can be determined. We compare the simulations with experimental studies on the phosphor temperature.
View Article and Find Full Text PDFWe show that with an appropriate combination of two optical simulation techniques-classical ray-tracing and the finite difference time domain method-an optical device containing multiple diffractive and refractive optical elements can be accurately simulated in an iterative simulation approach. We compare the simulation results with experimental measurements of the device to discuss the applicability and accuracy of our iterative simulation procedure.
View Article and Find Full Text PDFIn this study the applicability of an interface procedure for combined ray-tracing and finite difference time domain (FDTD) simulations of optical systems which contain two diffractive gratings is discussed. The simulation of suchlike systems requires multiple FDTD↔RT steps. In order to minimize the error due to the loss of the phase information in an FDTD→RT step, we derive an equation for a maximal coherence correlation function (MCCF) which describes the maximum degree of impact of phase effects between these two different diffraction gratings and which depends on: the spatial distance between the gratings, the degree of spatial coherence of the light source and the diffraction angle of the first grating for the wavelength of light used.
View Article and Find Full Text PDF© LitMetric 2025. All rights reserved.