LENS INFORMATION

Lens Strength:
Recorded in a measurement know as diopters (D), the strength of a lens can be manipulated by changing the material it is made from and by altering the curvature and shape of the lens. A minus (-) sign in front of the diopter numerical indicates that the lens is concave, a lens shape typically used to enhance distance vision. A plus (+) sign in front of the diopter numerical typically indicates a convex lens, a lens shape typically used to enhance close up vision.

Single Vision Lenses:
A single vision lens is an extremely common lens type because the lens has the same focal power throughout the entire lens. These lenses can be used to enhance your vision for reading or distance and corrects nearsightedness, farsightedness or astigmatism.

Progressive Lenses:
Progressive lenses are unique in that they have multiple prescriptions within the lens. These lenses are perfect for individuals who do not want to switch between multiple pairs of glasses. They are also perfect for individuals who do not like the visible and annoying line on bi focal glasses. Progressive lenses were created with natural vision in mind and they achieve just that. The prescription gradually increases in strength from the top of the lens where the distance prescription is located toward the bottom of the lens were the reading prescription is located.

Bifocal Lenses:
Bifocal lenses can be distinguished from other eyeglass lenses by the visible line at the bottom of the lens. This line is the border between the distance and reading prescriptions of the lens and is the simple solution to having 1 pair of eyeglasses. Like progressive lenses, bifocals allow for 2 different prescriptions in one lens yet with bifocals there is noticeable change between these prescriptions.



LENS MATERIALS

Plastic (CR-39):
An extremely common lens type that is a safe and reliable alternative to glass lenses is plastic CR-39. Columbian Resin #39 is a plastic polymer that was introduced in the 1950’s. Plastic lenses transmit visible light and absorb ultraviolet light better then glass lenses, making plastic the preferred choice by optometrists. Due to the physical properties of plastic lenses they can provide a greater index of refraction that allows these lenses to correct a multitude of vision irregularities.

Polycarbonate:
Polycarbonate lenses are arguably the #1 recommended lenses by optometrists and opticians practicing today. These lenses are often 20% thinner and lighter than plastic CR-39 lenses and have far better optical properties. This lens is a necessity for children’s glasses and for any individual that lives an active lifestyle because polycarbonate lenses are extremely impact resistant. Therefore these lenses are recommended to people with very strong prescriptions, sports players, kids, anyone who wants something light weight and all individuals who are safety conscious. With built in UV protection and basic scratch protection, this lens is recommended to almost all individuals.

High Index:
High Index lenses are a special type of lens that is typically used for stronger prescriptions in order to minimize the thickness of the lens. With non-high index lenses, the stronger the prescription, the thicker the lens needs to be in order to refract visible light into the eye. High index lenses feature a higher index of refraction so that light can have increased refraction with out increased thickness lens material. The index of glass lenses is 1.52 while the index for plastic lenses is 1.50.  High index lenses are available in various indexes from 1.53 to 1.74 thus allowing for high prescriptions with thin lenses. The thinner the material the lighter the lens and this is a must have for anyone with a strong prescription. Overall these lenses are great for strong prescriptions, they are durable and cosmetically more acceptable. Say goodbye to heavy lenses that magnify your eyes and say hello to high index!


SPECIAL LENSES

Non-Glare:
The problem with basic eyeglass lenses is the amount of reflection and glare that passes through the lens into the wearer’s eyes. To block the glare, a metal oxide coating is applied while the lenses are being created. With this coating in place reflections from fluorescent lights, headlights, streetlights, computer screens, along with all other sources of reflection are blocked from entering your eyes. Anti-Reflective (AR) coatings serve many purposes, from promoting healthy vision to enhancing your physical appearance. Non-Glare lenses allow an increased amount of light to enter the eyes, which enhances vision when the individual is in a low light setting. Arguably the best feature of Non-Glare lenses is their cosmetic enhancements. Without AR coatings, any individual who looks at a glasses wearer will see reflections on the lenses, a barrier from seeing these person’s eyes. With an AR coating your eyeglass lens, people will see your beautiful eyes when they look at you and not a reflection or glare from the surrounding area.

Scratch Resistance:
Although scratch resistant coatings do not make a lens  “scratch proof” these coatings drastically improve the lenses resistance to scratches. Polycarbonate, and progressive lenses come with basic scratch resistance, yet advanced coatings are available that are miles beyond the basic coatings that come with some lenses. These advanced scotch guard coatings prevent lens smudging, are fog and dust resistant, are much easier to clean and are outstanding at guarding against scratches.

Polarized Lenses:
When it comes to eliminating glare, polarized lenses are the way to go.  The words “polarized sunglasses” are often thrown around yet not many people understand what polarized lenses are really all about.  Most people know the basics; polarized lenses offer superior sun protection.  Yet there is much more to these technologically advanced and reliable lenses.

The Light

- Light from a light source is emitted in all different directions.
- Light in any given direction is said to be Polarized (A process or state in which rays of light exhibit different properties in different directions)
- Glare is horizontally polarized light.

The Polarized Lens
- A polarized lens is treated with a substance that forms a filter.

- This filter passes only light that does not match its orientation.  In sunglasses, the lenses are oriented in such a way to block out horizontally polarized light or glare.
- This light coming through the lens is now considered polarized.



What You See
- Because the polarized lens blocks out glare, your eyes see a clear view of the world, free of dangerous glare and distortion.


Polarized lenses are ideal for anyone who spends time outdoors or drives a car.  Bikers, fisherman, golfers, basketball players, baseball players, snowboarders, roofers, construction workers, police officers, mail workers and of course the average Joe should consider investing in a pair of sunglasses with polarized lenses.  If you care about your eyes and protecting your vision, polarized sunglasses are the best choice.

Eliminating glare from your eyesight will cut down on headaches, and will make it easier to drive in the sunlight.  It can drastically improve your ability in sports, but overall polarized lenses are essential to maintain healthy eyesight.



If you would like to check if your sunglasses are polarized follow these steps.

1)    Hold your glasses at arms length and look through one of  the lenses at a computer screen

2)    Slowly rotate the glasses to a 90-degree angle and see if the intensity of the glare increases or decreases.

3)    If your sunglasses are polarized the glare will significantly decrease.


Optix carriers a variety of polarized sunglasses such as Oakley, Maui Jim, Ray Ban, Carrera, Nike, and Coyote.  The Optix lab can also fabricate polarized sunglass lenses in almost any prescription to fit almost any frame!



DIGITAL LENSES

The use of digital lenses in ophthalmic eyeglasses is increasing in eye care practices all over the world. Although this technology has been around for quite some time, it is becoming more common and preferred among lens laboratories. Many people are confused with the concept of digital lenses, often thinking that the lens itself is some kind of highly advanced equipment that one would see in a Sci-Fi movie. The truth is, digital lenses are just like ordinary lenses yet it the manufacturing process that sets them apart from traditional lens manufacturing.

Digital lens processing offers a higher level of precision when creating the lens and also opens up the possibility to create extremely unique and versatile lenses in terms of shape and prescription. This is thanks to the equipment used to create the lens. By using processing equipment that requires the measure, analysis and computation of lens data in the form of numerical digits, both surfaces of a lens can be directly surfaced with a high level of accuracy. With this improved level of precision a patient will experience a more comfort in their prescription and a greater level of satisfaction. In the end, we can compare a regular lens to a tube television and a digital lens to a plasma flat panel television. Due to the manufacturing process, a digital lens allows for more peripheral vision and a sharper picture.

Instead of thinking of the term digital lens as an object think of it instead as a process; a digitally computed lens. There are many ways to digitally create a lens and this process is often referred to as the free-form process. Everything from the lens mold to the lens surfacing was creating using highly advanced software that digitally computed the data of the frame, the lens type, the prescription and the focal point. Yet it does not stop there, the lenses are then checked, buffed and polished using specialized equipment before they are ready to be dispensed.

In comparison, traditional lens processing does not use highly advanced equipment found in the free form process. Using lens molds with the prescription details already built in, the traditional process requires manual lens grinding and polishing. Although it seems that the quality of digitally processed lenses would be far superior this is not always the case. It is more so the quality of the production process of digitally produced lenses that exceeds the quality of the traditional lens process. Digital lenses allows for the customization of progressive lens designs that traditional processing cannot produce.