•Stimulated Emission – photon strikes excited state
causing it to emit a burst of photons
•Pumping source used to populate upper states can
be flashlamp, another laser or electrical
•Often use prism to
select pumping wavelength
•
•Advantages of
lasers
• 1) Intense
• 2) Monochromatic – very narrow
band
• 3) Coherent – all radiation at
same phase
• angle