The options in lens designs, materials and coatings can sometimes be overwhelming, particularly with the leap forward in lens technology over the past few years.   Our doctors and staff frequently attend seminars and review literature to stay current with lens advances.  We are happy to help you sort through the numerous options to select the appropriate lens for your prescription, visual needs, and lifestyle. 

If you would like an idea what you may encounter when discussing lens options, following is a brief introduction to some of the terms which often cause confusion for patients.

Bifocal vs. Progressive Lenses:
Bifocal and progressive lenses have a different prescription on the top, for distance, than they do on the bottom, for near.  These types of lenses become necessary for most people as their accommodation or focusing ability decreases, usually around fourty years of age.  Bifocals have a near “segment“ attached to a distance lens.  The segment is seen as a half-circle on the bottom, nasal portion of the lens.  Progressive lenses are ground with gradual changes in the curves of the lens from the top of the lens to the bottom of the lens.  The difference in the curve at the top versus the bottom of the lens results in a gradual change in power from distance at the top to near at the bottom of the lens, without any noticeable lines on the lens.

Transitions:
Transition lenses are photochromic, meaning they change from clear to tinted when exposed to ultraviolet light.

Digital Technology:
Conventional techniques for manufacturing progressive lenses use a large curved tool to grind the prescription into the lens. In contrast to this, 360 digital surfacing uses a digitally controlled diamond point with a precision of 0.1 microns to generate a complex design on the back surface of the lens. The front of the lens is then matched point by point with the back surface to optimize all elements of the prescription (ie-distance power, near power and astigmatism correction) while minimizing the distortion and aberrations which occur with older designs of progressive lenses.

The result of digital surfacing is a lens which provides wider clear viewing areas, significantly less peripheral distortion, and increased contrast particularly in low light conditions.

High Index Lenses:
These lenses are made from materials which have a greater ability to bend or refract light.  The result is a lens which is thinner and flatter, and yet still provides the same power as a thicker, more curved regular index lens.  This is particularly useful for patients with high prescriptions, so that their lenses will both look and perform better. 

Computer Glasses:
People who spend large amounts of time using computers often benefit from a pair of glasses made solely for this purpose, particularly as they reach presbyopia, or the difficulty focusing up close which begins around fourty years of age.  Standard reading glasses often do not work well for the computer because computers usually sit further away than where we typically read.  And although regular progressive glasses can be used on the computer, the area designated on the lens for computer work is often too small and too far down the lens, to sit for long periods of computer work, holding the head exactly right to use the computer portion of the lens.  The answer for many people is a pair of computer glasses, usually in the form of a progressive lens, but with the top portion of the lens designed for the computer distance, and the bottom portion of the lens designed for reading closer up.  Lenses designed specifically for computer use allow much wider computer and reading areas, as well as much more natural head and eye positions than standard progressives, making long hours on the computer much more comfortable.

We use mostly Essilor, Nikon and Zeiss lenses, due to the superior optics provided by theses companies, particularly in their latest digital designs . If you would like to learn more about lens options on your own, you can check out the following very informative websites.

essilor.ca
nikonlenswear.ca
zeiss.ca
 

The options in lens designs, materials and coatings can sometimes be overwhelming, particularly with the leap forward in lens technology over the past few years.   Our doctors and staff frequently attend seminars and review literature to stay current with lens advances.  We are happy to help you sort through the numerous options to select the appropriate lens for your prescription, visual needs, and lifestyle. 

If you would like an idea what you may encounter when discussing lens options, following is a brief introduction to some of the terms which often cause confusion for patients.

Bifocal vs. Progressive Lenses:
Bifocal and progressive lenses have a different prescription on the top, for distance, than they do on the bottom, for near.  These types of lenses become necessary for most people as their accommodation or focusing ability decreases, usually around fourty years of age.  Bifocals have a near “segment“ attached to a distance lens.  The segment is seen as a half-circle on the bottom, nasal portion of the lens.  Progressive lenses are ground with gradual changes in the curves of the lens from the top of the lens to the bottom of the lens.  The difference in the curve at the top versus the bottom of the lens results in a gradual change in power from distance at the top to near at the bottom of the lens, without any noticeable lines on the lens.

Transitions:
Transition lenses are photochromic, meaning they change from clear to tinted when exposed to ultraviolet light.

Digital Technology:
Conventional techniques for manufacturing progressive lenses use a large curved tool to grind the prescription into the lens. In contrast to this, 360 digital surfacing uses a digitally controlled diamond point with a precision of 0.1 microns to generate a complex design on the back surface of the lens. The front of the lens is then matched point by point with the back surface to optimize all elements of the prescription (ie-distance power, near power and astigmatism correction) while minimizing the distortion and aberrations which occur with older designs of progressive lenses.

The result of digital surfacing is a lens which provides wider clear viewing areas, significantly less peripheral distortion, and increased contrast particularly in low light conditions.

High Index Lenses:
These lenses are made from materials which have a greater ability to bend or refract light.  The result is a lens which is thinner and flatter, and yet still provides the same power as a thicker, more curved regular index lens.  This is particularly useful for patients with high prescriptions, so that their lenses will both look and perform better. 

Computer Glasses:
People who spend large amounts of time using computers often benefit from a pair of glasses made solely for this purpose, particularly as they reach presbyopia, or the difficulty focusing up close which begins around fourty years of age.  Standard reading glasses often do not work well for the computer because computers usually sit further away than where we typically read.  And although regular progressive glasses can be used on the computer, the area designated on the lens for computer work is often too small and too far down the lens, to sit for long periods of computer work, holding the head exactly right to use the computer portion of the lens.  The answer for many people is a pair of computer glasses, usually in the form of a progressive lens, but with the top portion of the lens designed for the computer distance, and the bottom portion of the lens designed for reading closer up.  Lenses designed specifically for computer use allow much wider computer and reading areas, as well as much more natural head and eye positions than standard progressives, making long hours on the computer much more comfortable.

We use mostly Essilor, Nikon and Zeiss lenses, due to the superior optics provided by theses companies, particularly in their latest digital designs . If you would like to learn more about lens options on your own, you can check out the following very informative websites.

essilor.ca
nikonlenswear.ca
zeiss.ca