Book excerpt: "The Field Guide to Solar Optics attempts to consolidate and summarize optical topics in solar technologies and engineering that are dispersed throughout literature. The field guide also attempts to clarify topics and terms that could be confusing or at times misused. As with any technology area, optics related to solar technologies can be a wide field. The topics selected for this field guide are ones that are frequently encountered in solar engineering and research for energy harvesting, particularly for electricity generation. Therefore, the topics selected are slanted towards solar thermal or commonly called concentrating solar power. The first section of the field guide provides background on energy needs and usage and where solar technologies fit into the energy mix. The next section covers properties of the sun and develop understandings for solar energy collection. The third section introduces optical properties, concepts, and basic components. In the fourth section, the various optical systems used in solar engineering are described. In solar, optical systems used for solar energy collection is commonly referred to as collectors (e.g., collector field). This term is used frequently in this field guide. Another term commonly used for solar collectors is non-imaging optics. The next section introduces concepts for characterizing optical components/systems and analysis approaches. Lastly, measurement tools commonly used in solar engineering and research are described. The fundamentals of the topics are provided. Providing methods or approaches to designs was not the goal of the field guide. However, the fundamental understanding can be extended and used for design of components and systems"--