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Chapter IX General Conclusion
Chapter IX
General Conclusion
As it has been already discussed in the present thesis, KDP crystals
play very prominent role in NLO applications. In India, majority of research
is carried out on characterization of NLO materials crystals, nevertheless,
only few research work is reported on the device applications. It is
interesting to note that in Raja Ramanna Centre for Advanced Technology
(RRCAT), Indore, the growth of 75 x 75 x 125 mm 3 KDP crystals is
reported. The optical homogeneity of KDP crystals was assessed by
Mach-Zahnder interferometer [1, 2]. The elctro-optic modulator using
DKDP crystal has been fabricated at RRCAT. Moreover, Type-II SHG cell
using KDP, with clear aperture of 50 mm and length of 25 mm have been
devised at the same institute for doubling Nd:YAG laser.
There are certain characterizations based on very simple techniques
but provide very interesting information. Michelson interferometer has
been used for imaging the surface micro-morphology of prismatic and
pyramidal faces of KDP. The spiral growth mechanism, which has been
discussed in chapter – II, has been imagined in form of concentric fringes
of equal thickness. These fringes originated from the screw dislocation -
generated hillocks on the crystal face were discussed [3].
Another technique employed to study the convection during the growth
of KDP crystals is the Shadow-graphy. This technique was employed to
map convection around growing crystal. The shadow-graph images are
helpful to quantify the free convection in terms of Grashof number and
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