Angora: A Free Software Package for Finite-Difference Time-Domain Electromagnetic Simulation

Angora is a free, open-source software package implementing the Finite-Difference Time-Domain (FDTD) Method. This article explains how to access and use Angora, and introduces its features. Examples of its configuration and use are given. These include treatment of planar stratified and random materials, the creation of current sources and incident beams, near-field-to-far-field transformation, optical imaging and nano-optics, and the recording of fields.