High Efficient Natural Light Illumination System Based on Photonics Engineering Components: Analysis, Design, And Applications
Light collector design
An optical structure is designed to be used outside the buildings for indoor illumination. To cover an entire building, light is concentrated using optical units. The important factor in the design is to produce parallel exit beam from the single unit. Two different optical surfaces are used: saw-toothed and elliptical, and the con-focus principle to design three optical units. Furthermore, design of collimators for the collecting unit and micro-structure diffuser for uniform illumination are in progress.
Microstructure linear light emitter
The major factors of illuminative environment are high rendering index and uniformity. The natural light illumination system (NLIS) is used to guide sunlight for indoor illumination. The NLIS consists of three subsystems: collecting, transmitting, and emitting. Nowadays, a variety of light emitters are available for different illuminative environments. This paper proposes the linear microstructure to diffuse the parallel light for indoor illumination. To increase uniformity and promote illuminative area, the light emitter includes two microstructures for distribution of light. Finally, the proposed light emitter gives illuminance uniformity and efficiency of 0.55 and 74.18%, respectively.
Light collimator with Afocal lens and TIR lens
This research presents a novel design of the collimator, which uses total internal reflection (TIR), convex, and concave lenses for the natural light illumination system (NLIS). The concept of NLIS is to illuminate building interiors with natural light, which saves energy consumption. The TIR lens is used to collimate the light, and convex and concave lenses are used to converge the light to the required area. The results have shown that the efficiency in terms of achieving collimated light using the proposed collimator at the output of the light collector is better than that of previous system without collimator.