Friedrich Risner

Friedrich Risner, known in Latin as Fridericus Risnerus, was a German mathematician from Hersfeld in Hesse, born around 1533 and dead on 15 September 1580. From about 1565 he worked as an assistant to Petrus Ramus, and in 1576 he became the first holder of the chair of mathematics at the Royal College in Paris. He is remembered chiefly for his 1572 edition Opticae thesaurus, the first printing of the seven books on optics by Ibn al-Haytham (Alhazen) together with the work of Witelo, an edition that later served mathematicians and natural philosophers including Kepler, Snellius, Descartes and Huygens. He is also credited as the first to propose a portable camera obscura for artists, a small wooden hut with lens-fitted holes in its walls and a paper cube inside for drawing. After the St. Bartholomew's Day massacre he returned to Hersfeld, where he died and was buried in the abbey.