02-05-2011, 10:34 AM
PRESENTED BY:-
SWATI LEKHA SATPATHY
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TERAHERTZ WAVES & ITS APPLICATION
What are Terahertz waves?
Terahertz (THz) waves refer to waves that are in the frequency range that is situated between the infrared and microwave region of the electromagnetic spectrum .
Characteristics
Frequency range- 100Ghz to 10THz
Wave length-1mm to 100 micro meter
Referred to as submillimeter radiation, terahertz waves,terahertz light, T-rays, T-light, T-lux and THz.
Travel in line of sight.
It is non-ionizing
penetrate a wide variety of non-conducting materials
can penetrate materials that are usually opaque to both visible and infrared radiation.
Sources
Terahertz radiation is emitted as part of the black body radiation from anything with temperatures greater than about 10 kelvin. While this thermal emission is very weak.
The only viable sources of terahertz radiation were :-
The gyrotron
the backward wave oscillator ("BWO"),
the far infrared laser ("FIR laser"),
Applications:-
1. Imaging:-
(A)How imaging done?
Disadvantages :-
unzip double-stranded DNA.
creating bubbles in the double strand that could significantly interfere with processes such as gene expression and DNA replication.
suffer from attenuation caused by rain and resonant absorption in oxygen and water molecules, so they are unsuitable for long-range radio communications
Conclusion
Tera hertz waves are more advantageous than other electromagnetic waves.
Due to its non ionizing property it will be used widely in medical imaging.
Terahertz imaging are now in demand for quality control & security purpose.