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Anti-reflection Coated Lens 91

Most patients drive vehicles and understand the advantage of anti-
reflection coating eliminating ghost images.
4. Reflections from back lens surfaces can also be annoying. This is most
noticeable with sun lenses because the dark lens acts like a mirror.
Backside reflections are also more prominent with aspheric lenses as
their flatter inside surface reflects more light.
5. Strong minus lenses can produce a “Coke bottle” look caused by light
reflecting from thick lens edges. The reflection appears as a series of
concentric rings. Modern anti-reflection coatings virtually eliminate
these unsightly rings.
6. Anti-reflection coating has become popular in recent years. As a result,
there is a growing perception among consumers that, quality eyewear
include anti-reflection coating. Offices that do not routinely recommend
anti-reflection coated lenses, risk having patient learn about it from a
friend, neighbour or a competitors advertising.

ANTI-REFLECTION COATING OF PRETINTED LENSES
Glass lenses in which the tint is in the lens material itself, may also be anti-
reflection coated. This is quite advantageous in several situations:
1. If a person desires a light tint in his lenses and yet it is felt that night
vision is hindered by it, anti-reflection coating may return the glass to
its previous non-tinted transmission. For example, pink tint may reduce
the lens transmission from 92% to 88%. Anti-reflection coating on the
lens will bring the transmission back to at least 92%, while multi-layer
coating may increase the transmission to above 92%. In spite of the
increased transmission, the pink lens maintains its characteristic of light
coloured appearance.
2. Sun lenses may be antireflection coated to advantage as well. For
example, the patient may find reflections from the back surface of the
sun lens disturbing. This is a genuine complaint because of the reflection
coming from behind. An anti-reflection coating allows majority of light
coming from behind the wearer to pass on through the lens without
being reflected back into the eyes.
3. Photochromatic lenses may be anti-reflection coated. This will increase
both maximum and minimum transmission by a certain amount. The
lens will transmit more light in both the lightened and the darkened
state. It also helps when lenses are dark by reducing backside reflections
from dark lenses.

DISPENSING TIPS
In dispensing anti-reflection coated lenses, always remember not to sell
half pair lens. Whenever only one lens is required, most laboratories will