Raman Scattering (Stokes & Anti-Stokes)

Optical Engineering

How It Works

Raman scattering is an inelastic optical scattering process wherein incident monochromatic laser photons interact with molecular vibrational modes. Photons that lose energy to excite molecular vibrations emerge at lower frequencies (Stokes shift), whereas photons that absorb existing vibrational energy emerge at higher frequencies (anti-Stokes shift).

Governing Equation
h · ν_{scattered} = h · ν_{incident} ∓ Δ E_{vibrational}