Page 88 - The Indian Optician Digital Edition January-February 2022

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Dr Prof Mo Jalie, SMSA, FBDO (Hons), Hon FCGI Hon FCOptom,
MCMI, is a Visiting Professor of Optometry at the University of Ulster in
Coleraine, and at the post-graduate facility at Varilux University. He served
for nine years as Head of Department of Applied Optics at City & Islington
College, where he taught optics, ophthalmic lenses and dispensing. He
is a recognised international authority on spectacle lens design and has
written several books including Principles of Ophthalmic Lenses. His most
recent book, Ophthalmic Lenses & Dispensing was translated into Russian.
He has authored over 200 papers on ophthalmic, contact and intra-ocular
lenses, and on dispensing; and is a consultant editor to The Optician (UK)
and technical editor to The Indian Optician journal. He holds patents for
aspheric spectacle and intra-ocular lenses. Jalie is a past-chairman of the
Academic Committee of the Association of British Dispensing Opticians,
and was the first Chairman of the Faculty of Dispensing Opticians. He is
the ABDO representative on the BSI committees on ophthalmic lenses
and spectacle frames and a past member of the Education Committee
of the General Optical Council. In 1998 Jalie was thrice honoured: he was
made Honorary Fellow of the British College of Optometrists, a Life Fellow
of the Association of British Dispensing Opticians, and in December of
that year he was granted the Max Wiseman Memorial Research Medal.
Dr Prof Mo Jalie
The second part of this paper shows how the
“Eyezen Start” lens provides best form performance for
both distance and near vision in a single design.
In order to improve the performance of the lens for near
IN COMMON vision, maintaining the same convex base curve, the asphericity
WITH THE WHOLE of the concave surface must be reduced to +12.5. The design
EYEZEN™ RANGE is shown in Figure 5, together with field diagrams for near
THE EYEZEN™ vision (Figure 5(a)) and the performance when this form is used
for distance vision (Figure 5(b)). When viewing near objects
START SERIES ALSO
the design is point focal out to 35º where the mean oblique
INCORPORATES error is nearly -0.25 D. When used to view distant objects the
ESSILOR’S BLUE- astigmatism at 35º is +0.30 D and the mean oblique error is zero.
VIOLET FILTER The aim of the Eyezen™ Start design is to provide best form
TO FILTER THE performance for lenses in both the distance and near vision
WAVEBAND BELOW zones of the lens.
455NM, FURTHER The convex surface of the design is a simple spherical surface
RELIEVING THE but the concave surface is a double aspheric design which has
EYE OF COMPUTER an eccentricity optimised for distance vision in the upper portion
VISION SYNDROME of the surface and a different eccentricity, optimised for near

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