title: Analytical light-ray tracing in two-dimensional objects for light-extraction problems in light-emitting diodes.
abstract: Light extraction from two-dimensional objects is discussed. Analytical calculations in terms of three different parameters have been applied to equiangular polygons to trace light rays during multiple reflections in a polygon. Based on the result that there are a finite number of incident angles in a polygon for a light ray, it was found that the triangle has the least chance to trap light rays among the polygons. The discussion has been extended to parallelograms, which have an advantage in light extraction to rectangles. Placement of a possible light source in polygons is discussed.
authors.affiliation: Materials Department, College of Engineering, University of California, Santa Barbara, California 93106-5050, USA. masui@engineering.ucsb.edu
authors.forename: Hisashi
authors.initials: H
authors.lastname: Masui
authors.forename: Shuji
authors.initials: S
authors.lastname: Nakamura
authors.forename: Steven P
authors.initials: SP
authors.lastname: DenBaars
mesh_terms: D000465:Algorithms; D016477:Artifacts; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008027:Light; D008029:Lighting / Q000295:instrumentation* / Q000379:methods*; D010783:Photometry / Q000295:instrumentation* / Q000379:methods*; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity