- 長野工業高等専門学校紀要 = Memoirs of Nagano National College of Technology (ISSN:02861909)
- vol.48, pp.1-10, 2014-06-30
May 21, 2012, solar eclipse was observed in Japan. This time, annular eclipse occurred over a wide range; i.e. the southern part of Kyushu, the southern part of Shikoku, the southern part of the Kinki, the southern part of the Chubu, such as the Kanto. Other regions became a partial solar eclipse. Approximately 83 million people are living in the path of annular phase, we were expected many people to observe the eclipse. Eclipse is a valuable opportunity to increase interest in science. On the other hand, when observing the sun, it runs a strong risk that leads to trouble in the eyes of people due to the strong sunlight. For example, in the case of the eclipse in Germany in 1912, solar eclipse retinopathy patients of 3,500 has occurred. We conducted our activities for many people to observe the eclipse safe. One of them is the spread of safe solar eclipse observation method, another is a research study of the safety of the solar eclipse glasses.In this paper, we report the transmittance measured in the various filters; solar viewing glass on the market, and their substitutes. These are valuable archival material related to solar observation glass for the solar eclipse in the future.