Page 160 - The Indian Optician Digital Edition Jan-Feb 2020

IMPACT OF SUNGLASSES

AND RADIATION ON VISION

- PART 2

TYPES OF LENSES TO PROTECT EYES FROM RADIATION

Sanjay Kumar Mishra
Scientist at Dr. R. P. Centre
for Ophthalmic Sciences, AIIMS
New Delhi

UV rays, radiation and glare may colour by dipping them into a dye
have a serious impact on one’s vision, solution. A gradient lens varies in
a reality that must be considered transmission over the surface of the
while deciding the lens for one’s lens as their upper portion becomes
eyewear. Today, there are varied types dark and then gradually lightens
of lenses available in the market, toward the lower section. The
thanks to the advanced technology unsatisfactory tint may be bleached
that offers different tints to cater to out for re-tinting. Polycarbonate
Mahesh Chandra lenses have an anti-scratch coating
Senior Optometrist, Sushila Tiwari all the optical needs. It is important
Hospital and Govt. Medical College, to understand the types of lenses that is not uniformly permeable
Haldwani, Uttarakhand that can safeguard the eyes and help to dyes, although some of the
one see better. Read on to learn more manufacturers have a selection of
about them. pre-tinted polycarbonate lenses.
High index plastic lenses dye more
DYEING slowly than CR-39 lenses and require

Plastic lenses offer great versatility a special process, while some of the
as they may be tinted in any desired high index lenses cannot be dyed.

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