Abstract

Directly transporting sunlight for use in indoor lighting applications is an efficient way to utilize solar energy. This study proposes a tree-structured light guiding system (TLGS) to collect sunlight and transport it for indoor illumination. The use of asymmetric light couplers in a TLGS increases the amount of accumulated sunlight. An analytic ray tracing model of the asymmetric coupler is proposed to present the angle and height distributions of the propagated rays. The cutoff angles were derived, and this cutoff condition was used to determine which rays are able to travel through the coupling region. In simulations, the couplers with coupling angles (${\theta }_{\text{coup}}$) of 30° and 50° were conducted, and the large ${\theta }_{\text{coup}}$ coupler provided high coupling efficiency (0.450). The orthogonal incidence method was adopted to increase coupling efficiency (0.646), and subsequently the amount of accumulated sunlight. The amount of accumulated sunlight in a TLGS was increased by 44%.

© 2013 Optical Society of America

Design of a high-efficiency collection structure for daylight illumination applications

Meng-Che Tsai, Allen Jong-Woei Whang, and Tsung-Xian Lee
Appl. Opt. 52(36) 8789-8794 (2013)

Indoor daylighting using Fresnel lens solar-concentrator-based hybrid cylindrical luminaire for illumination and water heating

Mayank Gupta, Atul Kumar Dubey, Virendra Kumar, and Dalip Singh Mehta
Appl. Opt. 59(18) 5358-5367 (2020)

Modified optical fiber daylighting system with sunlight transportation in free space

Ngoc-Hai Vu, Thanh-Tuan Pham, and Seoyong Shin
Opt. Express 24(26) A1528-A1545 (2016)

Mean wavelength-based Fresnel lens solar collector for eliminating the hotpot problem in daylighting systems

Vikas Kumar, Devendra Singh Bisht, and Harry Garg
Appl. Opt. 62(34) 9188-9197 (2023)

Concentrated and piped sunlight for indoor illumination

L. M. Fraas, W. R. Pyle, and P. R. Ryason
Appl. Opt. 22(4) 578-582 (1983)