Thin Lenses
So many factors are considered in determining which lens material is best for each situation. Some criteria are: How strong is the prescription? What is the type of frame (metal/plastic/rimless)? What are the sizes of the lenses (larger=thicker)? And, what is your tolerance for edge thickness? Visual Effects high-tech, thin lens options.

High-index
High-index = Lenses that are thinner & lighter in weight because the material is denser.

Standard plastic (CR-39) is the material of choice with low to moderately strong prescriptions. It is relatively inexpensive, lighter than glass and scratch resistant. From moderately strong to severe, different "high-index" materials are called for. The term "high-index" refers to any lens material with an index of refraction greater than the 1.49 of CR-39.

All lens materials being denser than air have higher refractive indices ranging from the 1.49 of CR-39 through 1.60 through 1.66/7 to finally 1.74, corresponding to progressively denser and thinner high-index lenses. 1.60 lenses are about 30-35% thinner than CR-39, 1.66 lenses are about 40% thinner, and 1.74 are about 50% thinner than CR-39.

Aspheric
Originally designed for farsighted (plus) lenses to reduce the thick bulge, this special design now is available for nearsighted (minus) lenses as well. This type of lens uses a computer design that flattens the curves of both surfaces to reduce thickness, decrease the magnification effect and improve optics. Couple this design with high-index materials to get great looking strong prescription lenses. The latest addition to this category is "atoric" surfaces, which help improve optics by reducing distortion in astigmatic lenses.

Polycarbonate
Newer designs have decreased the distortion that was a problem with this material in the past.

This was the first lens material introduced that was thinner and lighter than CR-39. It's most significant benefit is its impact resistance - 10x stronger than plastic. Because of this feature we use it for sport and safety frames, kids glasses, and drill mounts.

Progressive Bifocals
This is the most exciting area in today's high-tech designs. Newer progressive addition lenses that have been introduced in the last few years have made adaptation from single vision lenses a snap.

With improvements like; the translation from distance to near being significantly smoother, less distortion around the sides and larger reading zones, these variable focus lenses have been the first choice bifocal design for years at Visual Effects Optical. The very latest designs that have been introduced due to new manufacturing techniques utilizing digital computer lens designs that elevate performance to new heights by reducing distortion and increasting the size of he usable are to see through. These "high definition" digital free form lenses have become the new state-of-the-art improved optics progressing lenses.

Photoreactive
Self-darkening lenses. The wait is over! The latest generation of plastic changeable lenses just released in 2008 is finally a great product. Virtually all the past negatives have been addressed in this sixth generation design. These lenses are now clear indoors (no residual tint) and turn to dark sunglasses with direct exposure to sunlight in less than a minute.

Since it requires direct sunlight to change, its only remaining downside is its inability to change much inside a car. These lenses are scratch resistant and are available in a full range of materials and lens choices.

Polarized
To those eyes unfamiliar with this high-tech sun lens, it is the most difficult to describe in words. The only way to fully appreciate this lens is with a real-life demonstration in sunlight. We encourage anyone to visit us for a side-by-side comparison next to a non-polarized lens to truly experience the benefits of this most effective sun lens.

Simply, polarized lenses eliminate sun glare from reflective surfaces. Glare is caused by the sun's light reflecting off of usually horizontal surfaces like water, snow, pavement, and even cars, as it scatters in all directions. This reflected glare causes us to squint our eyes to shield us from its annoying affects. It is also why it is difficult to see through the surface of water.

Polarized lenses have a type of filter that allows only a certain path of light to pass through the lens. Glare is now eliminated due to the single direction or path of light (instead of multiple) through the lens. For fishing enthusiasts these lenses will allow you to see beneath the surface of the water to the fish. Being the most effective sun lens, anyone desiring top performance for any reason will appreciate how these lenses work.

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