Coherence, Physics

COHERENCE :

1) Visible light energy is emitted when the excited electrons in atoms undergo transitions to the ground state.

2) In ordinary light sources, these transitions take place at random in time and the light waves received at a point on a screen bear no definite phase relation among them.

3) But, in a laser source, electronic transitions take place in an 'orderly way' and the light waves emitted have a consistent phase relation which does not change with time.

4) This is called 'temporal coherence' and is the most important characteristic of laser light.

 

Posted Date: 10/18/2012 8:57:03 AM | Location : United States







Related Discussions:- Coherence, Assignment Help, Ask Question on Coherence, Get Answer, Expert's Help, Coherence Discussions

Write discussion on Coherence
Your posts are moderated
Related Questions
Common dime-store cells and batteries The cells you see in the grocery, department, drug, and hardware stores which are popular for use in household convenience items such as


How many sizes are there of lighting fiber optic? Literally hundreds, by some microns to over an inch into diameter, multicore and solid core, and square shaped ribbons, sheet

Temperature joule; J (after J.P. Joule, 1818-1889) The derived SI unit of energy described as the amount of work done by moving an object by a distance of 1 m by applying a fo

A medium is known as denser if the velocity of ray in that phase is fewer than the speed of the wave in other phase.     In comparison to air velocity of sound is main in water,

How is temporal coherence key of characteristics of laser? Temporal coherence: This coherence is a measure of the correlation among the phases of a light wave at various poi

Functions of the commutator:  A commutator is a device, which under certain conditions changes ac into dc and vice versa. The commutator is a form of rotating switch placed

If the resultant force acting on a body of constant mass is zero, the body's momentum is: a) Increasing b) Decreasing b) Always zero d) Constant Ans: If

how does expansion occur

Sievert; Sv: The derived SI unit of dose equivalent, explained as the absorbed dose of ionizing radiation multiplied through internationally-agreed-upon dimensionless weights,