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Book review: Spiros Kitsinelis: Light Sources: Basics of Lighting Technologies and Applications

This book covers most electric light source technologies, both historical and existing and looks ahead to possible future developments in light source technology. It starts with a relatively brief discussion of the basic principles of light and vision, the main body of the text contains in-depth information concerning the main light source technologies, and then the book closes by providing an application context for the light source technologies discussed within the text. For an introduction to the basic principles of light and vision, many texts exist that cover this significantly better than this book does. This chapter does introduce some important terms used later in the text, for example those related to colour rendering and colour temperature, and as such provides a basic context for the rest of the book. The book comes into its own when it starts to discuss light source technologies. For a student wishing to understand the complexities of the wide range of existing light sources, it provides a large amount of valuable information that is well presented. From the chemistry of each light source to the physics of its operation and the resultant performance characteristics, each technology is described in detail with a wealth of graphs, drawings and photographs to help explain the concepts. Each chapter finishes with a list of references for further reading if desired. The final sections concerning application issues of the light source technologies contain both subject overview and comprehensive information. The discussion of light source considerations for a range of application spaces is very general and of relatively limited use in designing lighting for real spaces. Many other lighting guides and application texts deal with this topic in a more comprehensive and useful form. However, this is followed by quite an in-depth discussion on light sources and health. Whilst this area of lighting is still a relatively new discovery and as such is still in its infancy for general application, there is a wealth of information contained within this section. Discussions on circadian rhythms and the influence of light on the human body clock are relatively brief, just enough to whet the appetite of the reader for further information. However, this is followed by a suitably in-depth discussion on the effect of light on subjects with visual impairments or medical conditions, including a list of medical conditions that may result in photophobia, and this section is supported by a suitably wide ranging list of references for further reading. Where this book excels is in the obvious knowledge of the author concerning light source technologies. Where this book lets itself down is in the labelling of some diagrams and figures and a number of occurrences of over-simplification of considerations or concepts. These prevent the book from really addressing light source technologies in application and therefore achieving its undoubted potential.