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204 Ophthalmic Lenses

PRESBYOPIA AND SPORTS LENS
Presbyopia does not stop people playing sports. The important fact is that
presbyopia has an ongoing effect on your eyes, so your corrective lens
prescription may need to be changed over time, as a result. So sports
progressives are very important.
With most sports activities, distance vision is the primary need- for
presbyopes too. Visual needs with sports progressives are different from
those of general wear. The lenses are larger and the peripheral lens area is
used more often and more intensively. The whole lens surface of sports
progressives is individually calculated, taking into account all data on the
wearer and sports frame. The progressive is optimized point to point right
out to the very edge of the lens, ensuring best acuity at all ranges. Tailor
made progressive designs which takes into account the following factors
are key to success in sports progressives:
1. Subjects posture
2. Frame position
3. Amount of head tilt used for near vision
4. Area of the lens used frequently.

Designing Prescription in Sports Progressive Lens
In designing the near addition for the high base curve sports sunglasses,
the choice of addition is done on how the spectacle will be worn. If the
spectacle will be worn for everyday use select the same add value and if
the spectacle will be worn for sports, with occasional use at near, reduce
the general wear add by 0.50 D. Reducing the add gives greater comfort in
wear by reducing peripheral distortion and improved field of vision. The
0.50 D addition reduction represents the normally used sports near vision.
A general guideline for selecting the near add as under:
Sports spectacle tennis 2.00 D if general wear addition is 2.50 D
Sports Spectacle golf 0.75 D if general wear addition is 2.50 D

SUMMARY

Sports lenses dispensing is a specialized part of ophthalmic optics. It is
established that vision is critical to sporting performance. The art of
dispensing is to maximize the visual information. While the eye care
profession has traditionally been considered satisfying, secure and relatively
paid, these advantages over recent years have not been encashed. The role
of eye care practitioners is changing and as one door closes another opens.
The market for sports lenses is expanding, lucrative and is now available.