Charles Fabry

Educated at the École Polytechnique, Fabry was appointed professor of physics at the University of Marseille in 1894. Partnering with Alfred Pérot, he developed the Fabry-Pérot interferometer, using multiple reflections between two semi-reflective parallel plates to measure wavelengths with unprecedented precision.

In 1913, using ultraviolet spectroscopy, Fabry and Henri Buisson demonstrated that atmospheric absorption of solar ultraviolet light is caused by a concentrated layer of ozone in the stratosphere, discovering the protective ozone layer. In 1921, he was appointed to the Sorbonne and became the first director of the Institut d'Optique Théorique et Appliquée.