Jules Célestin Jamin (30.05.1818-12.02.1886) was a French physicist and a member of the Paris Academy of Sciences (1868). He was born in Termes. He graduated from the École Normale. In 1852 — 81 he was professor at the École Polytechnique, from 1863 also professor and from 1868 director of the physics laboratory of the University of Paris.
His research was in the field of electromagnetism and optics. He measured the refractive index of many substances and studied the speed of propagation of light. He studied the reflection of light from metals (1847) and from transparent bodies (1857). In 1856 he constructed an interference refractometer (the Jamin interferometer).
A corresponding member of the St Petersburg Academy of Sciences (1884).