VisionSource! - North America's Premier Network of Private Practice Optometrists
North America's Premier Network of Private Practice Optometrists

2 locations to serve

your eyecare needs.

University Place Office
Yelm Office


 

 


 

LENS SERVICES

 

When you're buying a new pair of eyeglasses, there are a number of choices you have to make. Some of them are fun: what the frames will look like, what color they’ll be, what style you’ll get. Some choices, however, require a little more understanding of what you're getting yourself into. Specifically, what do you want your lenses made out of and what lens options will you benefit from? New technologies have brought us a range in lens powers, materials and lens features that are virtually unlimited. However, not all available features are right for all of our patients. As such we provide you with a brief discussion of each of these features so when you visit our office you will have some ideas of what features might work best for you. We will be happy to discuss all of these and advise you as to how they fit your needs.

 

LENS MATERIALS

There are basically six standard eyeglass lens materials. These lens materials can be differentiated by their weight, thickness, and optical performance. Our doctors and staff are well trained to make recommendations as to the best material for your prescription and lifestyle needs. Many of these products are sold under trade names, but fall into the following categories:

  • CR-39 (aka normal plastic) is the most widely-used lens material, is the least expensive and offer excellent vision quality.   This material cleans and tints easily, and is widely available with all other features. 
  • Mid-index (1.56) and high-index plastic (1.6, 1.67, 1.7) are thinner and lighter alternatives to CR-39 that offer excellent vision quality.  The higher the index number, the thinner the lenses so it is useful in higher prescriptions to reduce the thickness and weight of the lens. It offers 100% UV protection and is a stronger lens material than CR-39 so it is useful in drilled and rimless frames. Cost usually increases with the index and thinness.
  • Trivex is a relatively new material.  It is impact resistant and provides 100 percent UV eye protection, so it is recommended for children or people who play sports. The lenses may be slightly thicker than polycarbonate, but are lighter and superior optically. Trivex is also good for drill-mounted rimless frames because it will not crack as easily as polycarbonate.
  •  Polycarbonate is extremely durable—as proved by the fact that polycarbonate is also the material used for bulletproof vests and space shuttle windows. These lenses are light, impact resistant and offer 100 percent UV eye protection. Polycarbonate lenses are recommended for children, who may run and fall on their glasses and both children and adults who play sports and may be hit by an errant ball or elbow. Polycarbonate has inferior vision quality (especially in higher powers) and is less scratch resistant when compared to plastic, glass or Trivex. 
  • Glass used to be the norm in eyewear lens materials—hence the name “eyeglasses.” It has declined in popularity, but it offers the widest field of vision for wearers and the best scratch resistance. Drawbacks of glass are the extreme heaviness (twice that of plastic), the possibility of breaking the glass and it is more expensive. High-index glass lenses are still twice the weight of plastic lenses (although thinner) and some do not meet the minimum impact resistance set by the FDA.  We will not use glass in rimless and drilled frames because it chips very easily.

It's always a good idea to talk to your eye doctor. He or she will tell you what you should and shouldn't use, depending on your unique condition and the strength of your prescription.

 

Fixed Tints

Lenses are often tinted for a variety of reasons. Sometimes the color is added as an accent of color to the already stylish frame. Other times the patient  has a medical issue such as sensitivity to bright light (Photophobia), migraine headaches or severe allergies

 

Tints can be a solid color, where the color is the same throughout the lens or gradient where the top of the lens is dark and the bottom of the lens is clear. We can even just tint the edges of the lens to minimize the thickness or complement the frame.

 

 Sunglasses

Sunglass colors tend to range from a neutral gray, brown, green and variations of their combinations. We offer any color or density you can imagine. Mirror finishes are also available.  We recommend that sunglasses be 100% UV protected.

 

Polarized Sun Lenses

Polarizing sun glasses eliminate reflected glare from wet road surfaces, bumpers, windshields and water on the road, lakes and rivers. This is particularly useful for drivers, boaters, fishermen, hunters and many other outdoor activities.

 

Yellow Lenses and Hunters

Hunters tend to like yellow or orange lenses since they increase contrast during the daybreak hours or twilight hours. During those hours the sun is at its greatest angle with the earth and therefore light passes through a denser atmosphere. As such, light is more bluish during those hours. As this bluish light passes through a yellow lens the blue wavelength is filtered out and only the remaining colors can go through. Since the blue light can't get through the lens, blue objects appear to be darker or even black. That increases contrast against all the other colors.

 

 

Children & Sunglasses

Dermatologists tell us that many skin cancers originate from excessive sun exposure.  For younger children, ultra-violet from the sun is even more damaging. This holds true for children's eyes as well as their skin.  We recommend sunglasses for children as well as a cap with a "bill" to protect their young eyes.

    

 

 

Photochromatic Lenses

Photochromatic lenses change with the light.  Light from the sun contains ultra-violet wavelengths (over 700 nm).  It is the ultra-violet that creates a change in the chemistry of the lens.  This change causes the lens to darken.  Photochromatic lenses block over 95% of the Ultra-violet rays.  When indoors, and out of the effect from sunlight, the lenses lighten up nearly perfectly clear.  When in your car, the lenses are only about 25% dark due to the fact that the car windshield blocks about 50% of the UV.  We will be happy to help you with the brand of photochromatic lenses that are appropriate for your prescription and color needs.

 

Transitions™ (one of the brands of photochromatic lenses) come in two densities.  If you prefer clear lenses when you are indoors, the the traditional Transitions™ lens is best for you.  However, if you are sensitive to bright light and prefer a comfortable light tint indoors and you want moderate darkening in the car, then you should use Transitions XTRActive™. 

 

 

 

 

 

 

 

           

 

 

 

 

Hard Coat Finish

A hard coat finish is a coating of silica particles that are baked on the surface of the lenses.  This finish resists scratches and nicks.  This hard coat finish is baked on the front and the back surface of both lenses.  Over a period of time,  the hard coat finish will reduce scratches by approximately 75%. 

 

Anti-Reflective Coating

When you look at a high quality camera lens you will note a purplish sheen to the surface of the lens.  This is an Anti-Reflection (ARC) Coating which is baked on the lens.  This same anti-reflection coating is available in your glasses.  This coating reduces reflections and glare from lights by over 80%.  This feature is particularly useful when driving at night, when there is a multitude of streetlights and car lights that are reflecting off the surfaces of your lenses.  Glare while driving or while on a computer can create a lot of visual discomfort.

  

Another cool feature of ARC is that it is "Hydrophobic".  This means that water beads up on a lens with ARC on it.  As noted in this example, on the right lens, water beads up and will roll off the lens when it is raining.  Water spreads out on the left lens and makes it impossible to see through it. 

 

The final feature of ARC is that it also has the hard coat finish built into it.  This gives your lenses the same hard finish as the Hard Coat listed above.