Characteristics of Laser beam
A laser beam has the following important characteristics:
1. Directionality: An ordinary source of light emits light waves in all the directions and is highly divergent. But the divergence or angular spread of a laser is very small.
2. Monochromaticity: It means that all the laser rays have same wavelength and frequency when they are emitted from the same source.
3. Brightness: A laser beam has brightness many times in magnitude greater than that of conventional sources due to high directional property of laser beam.
4. Coherence:Two or more light waves are said to be coherent if they bear a constant phase relation among themselves. Coherence can be classified into two ways:
a) temporal coherence
b) spatial coherence.
Do you know the difference between the two?
Do you know about the spontaneous and stimulated emission?
Think, we will discuss it later on!!
Indian Institute of Managements
National Entrance Screening Test (NEST)-2011
NEST will be conducted for 5 years integrated masters programme at following institute:
a) National Institute of science Education & Research (NISER), Bhubaneswar, Orissa. For more information, see:
b) Centre for Excellence in Basic Sciences (CBS), see:
To apply online visit
last date of receipt of application is March 16, 2011.
Date of test is May 29, 2011.
All students admitted are assured of INSPIRE fellowship.
Post graduate diploma in management
Admissions in post graduate diploma in management (Financial management) -2011 ,in National Institute of Financial management.
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