In: Physics
Explain why lasers can be used to perform surgery and cut through metal while incandescent light cannot.
The word LASER is an acronym of Light Amplification by Stimulated Emission of Radiation. It is a device to produce a strong, monochromatic, collimated and highly coherent beam of light. It works in the phenomenon of 'stimulated emission'.
Laser has some characteristics that are completely absent in incandescent light. They are:
(i) Laser light is highly monochromatic
The laser light is a beam of monochromatic light because all photons inthe laser light have same energy, , same frequency, and also same wavelength, .
(ii) Laser light is highly coherent.
Since the emission of all photons are in phase, the laser beam is coherent.
(iii) Laser light is highly intense
The intensity of laser beam is very high because all the photons in the beam are coherent.
(iv) Laser light is highly directional
A laser beam is highly directional.Light from other sources can be made parallel beam by a lens or a mirror,but the beam divergance is much greater than that for laser light.
These properties of laser light enables it to be used in surgery and cut through metals.