Raman processes involve light interacting with the vibrational excitations of molecules making up the medium;as a result, the photons of light lose or gain energy, which changes their frequency.

• 拉曼过程则牵涉到光与组成介质之分子的振荡激发态，由于彼此的相互作用，光子会损失或增加能量，导致频率的改变。