Scale-Dependent Light Scattering Analysis of Textured Structures on LED Light Extraction Enhancement Using Hybrid Full-Wave Finite-Difference Time-Domain and Ray-Tracing Methods

Tsung-Xian Lee and Ching-Chia Chou
Additional contact information
Tsung-Xian Lee: Graduate Institute of Color and Illumination Technology, National Taiwan University of Science and Technology, Taipei 10607, Taiwan
Ching-Chia Chou: Graduate Institute of Color and Illumination Technology, National Taiwan University of Science and Technology, Taipei 10607, Taiwan

Energies, 2017, vol. 10, issue 4, 1-12

Abstract: A multiscale model that enables quantitative understanding and prediction of the size effect on the scattering properties of micro- and nanostructures is crucial for the design of light-emitting diode (LED) surface textures optimized for high light extraction efficiency (LEE). In this paper, a hybrid process for combining full-wave finite-difference time-domain simulation and a ray-tracing technique based on a bidirectional scattering distribution function model is proposed. We apply this method to study the influence of different pattern sizes of a patterned sapphire substrate on GaN-based LED light extraction from the micro-scale to the nano-scale. The results show that near-wavelength–scale patterns with strong diffraction are not expected to enhance the LEE. By contrast, micro-scale patterns with optical diffusion behavior have the highest LEE at a specific aspect ratio, and subwavelength-scale patterns that have antireflection properties show a marked enhancement of the LEE for a wide range of aspect ratios.

Keywords: light-emitting diodes; light extraction efficiency; textured structures; light scattering; bidirectional scattering distribution function (BSDF); bidirectional reflectance distribution function (BRDF); bidirectional transmittance distribution function (BTDF) (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2017
References: View complete reference list from CitEc
Citations: View citations in EconPapers (1)

Downloads: (external link)
https://www.mdpi.com/1996-1073/10/4/424/pdf (application/pdf)
https://www.mdpi.com/1996-1073/10/4/424/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:10:y:2017:i:4:p:424-:d:93856

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().