抄録
Radiation energy from the sun is divided into three categories: 52% is for visible radiation, 42% invisible infrared radiation, and 6% invisible ultraviolet radiation. As they inseparably constitute solar radiation, if you bask in the sun you are certainly exposed to ultraviolet radiation whether you like it or not. In my childhood solar ultraviolet radiation was considered beneficial to our health and sunbathing was recommended. Recently, however, the negative effects of solar ultraviolet radiation on living organisms have been observed. This lecture covers five topics, including the criteria for evaluating the hazards and the benefits of solar ultraviolet radiation: 1. Light and ultraviolet radiation (UV), 2. Depletion of stratospheric ozone and the increase of solar ultraviolet-B radiation (UV-B), 3. UV effects on human skin and eyes, 4. Characteristics of solar UV-B and ultraviolet-A radiation (UV-A), and 5. Practical prevention for solar UV exposure.
