Diffraction-free incomplete annular beam is produced by using destructive interference between two modified and unmodified annular beams, where modification is done on its pitch using modulo operation. The holographically generated beam remains unchanged upto 1.5cm. © 2005 Optical Society of America.

RAJIB CHAKRABORTY

Applied Optics and Photonics

A GHOSH

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

Journal	Optics InfoBase Conference Papers
Publisher	Optical Society of America
ISSN	2162-2701