Theoretical approach to the transmission coefficient of light diffracted from a luminescent rod

Abstract

In this thesis a simulation is described to estimate the transmission from a luminescent rod (Lumirod) with a pyramid structured diffraction grating. The aim is to optimize the transmission. A Lumirod is a rectangular phosphor cuboid that absorbs and emits light. Most of the emitted light remains captured within the Lumirod, due to its high refractive index. When transmitted from the diffraction grating on one side of the rod, the light is coupled out. This phenomena has theoretically been approached with a simulation to calculate the total transmission coefficient. For a grating constant of 500nm this coefficient is 0.312, and for a 2mm period the total transmission 0.349 is obtained. A greater variety of diffraction structures should be modeled to make a solid statement about the structure that optimizes the transmission.