Biological background, photometric assessment and transfer to application

Understanding of biological effects of light has dramatically increased during the last ten years. After proof of a third photoreceptor in the human eye chronobiological effects of light as well as direct alerting effects have first been investigated in scientific studies. Meanwhile these effects are also accessible for applications. Beneficial effects of light have been proven in medical applications like hospitals or nursing homes already years ago. Recently other application fields like schools or offices have been addressed with good success.

The presentation will give a brief introduction to biological basics of effects of light on humans and will continue with recommendations how to transfer these new findings to lighting applications. Basic ideas for a circadian photometry and the current status of standardization activities in Germany and Europe on this topic will be shown.

Some examples how these biological effects have been used in lighting applications to improve biological parameters like circadian rhythm, well being, alertness, cognitive functions and others will be shown. Among those examples are lighting installations in hospitals, schools, nursing homes, and offices. Finally ideas how to address assessment of energy efficiency related to biologically efficient pula pula inflavel lighting will be discussed.