Chandrasekhara Venkata Raman was an Indian physicist who made groundbreaking works in the field of light scattering. With his student K. S. Krishnan, he discovered that when light traverses a transparent material, some of the deflected light change wavelength and amplitude. This phenomenon was a new type of scattering of light and was subsequently known as the Raman effect (Raman scattering). Raman won the 1930 Nobel Prize in Physics and was the first Asian person to receive a Nobel Prize in any branch of science.
Basically his field was physics. He also won Nobel prize in physics in 1930.