Sunglasses

Sunglasses are something most everyone has or has had at one point in their life or another. The problem is, few people really know what to look for in sunglasses, and besides the current styles, and how they fit your face, how to choose the right pair. Many people really could not tell you the difference between a hundred dollar pair and a five dollar pair, other than the brand, or quality of materials. So, this brings to light the question of whether or not it really matters which pair of sunglasses you choose, and how features like tinted, reflective, photochromic and polarizing on sunglasses really makes a difference.

The following is a look at sunglasses not just from a fashionable point of view, but a look at how the various styles and technology behind the different lens compositions affect you and how you should be choosing your sunglasses.

Does price really matter?

When given the choice of spending $10 or $100 on a pair of sunglasses, which would you more likely choose? If you really do not know or see any benefit in the $100 pair over the $10 pair, the choice would seem obvious. However, what you pay for your sunglasses often reflects how well they will protect your eyes. This is not always the case, but the truth is, sunglasses are more than just tinted lenses in a frame. When choosing your glasses, look beyond price. Look for the glasses that best meet the following four criteria for what a good pair of sunglasses should do for you:

Criteria 1: Sunglasses should provide protection from ultraviolet rays in sunlight. Ultraviolet (UV) light can contribute to vision problems, contribute to cataracts, etc., and is damaging to the cornea and the retina, so you want a pair of sunglasses that will eliminate UV rays completely.

Criteria 2: Sunglasses should provide protection from intense light. Most sunglasses meet this criteria simply with tinting, but it is important to understand why this is important. When the eye receives too much light, it naturally closes the iris, then you squint. If even after these measures are taken there is still too much light, your retina will be damaged. While all sunglasses block some light, good sunglasses can block light entering the eyes by as much as 97 percent to avoid damage.

Criteria 3: Sunglasses should protect your eyes from glare. As you probably know light can reflect off certain surfaces causing a bright spot of light to form, which hides, or distracts the viewer from other objects. Your sunglasses should eliminate this kind of glare by using polarization.

Criteria 4: Your sunglasses should eliminate specific frequencies of light, such as those that blur vision or enhance contrast. Sunglasses often have different options for lens colors, and specific colors work better in specific situations. So, choose the glasses that provide elimination of the light frequencies that need to be eliminated for the situation you are in (dusk, sunrise, fog, etc.)

Basically, you get what you pay for, and when you choose a cheap pair of glasses you often have to give up one or more of these features in order to accommodate the price. In some cases, not only do you eliminate an important protecting feature, but you actually enhance the negative aspects through your choice. For example, if your sunglasses do not provide UV protection, you actually are increasing your exposure to UV rays because the glasses block some light, making your iris open more, to allow more light in, and thus putting your retina at greater exposure to the harmful UV rays.

The fact is simply that if you buy the right pair for your use, you will get protection, and if you don't, your money is wasted. Just remember when selecting sunglasses that you do not want to pay for the brand, you want to pay for the features. So, buying knock offs to get the brand on it for cheaper is not going to do you any good; the brand is not going to protect you, it is the features that brand may offer. While the glasses may look like the real thing, the lenses themselves are different, and will not offer the same amount of protection.

How important is this protection?

To understand the importance of choosing quality sunglasses you have to understand how light works. The right sunglasses will modify the light that meets your eyes so it is not harmful, and thus protect your eyes so that they last longer and work better.

Light, or light waves consist of electromagnetic energy, and we can see light that is within a specific wavelength range-from 400 to 700 billionths of a meter (nanometers). The shorter the wavelengths the more electromagnetic energy, this energy can be harmful to the retina if it gets too much. Of visible light, violet has the most energy and red the least. Just above the visible light spectrum is ultraviolet (UV) light, which can hurt the cornea and retina of the eye. So, because sunlight is rich in UV light, it is highly important that you protect your eyes from it.

Sunglasses use a variety of technologies to eliminate the problems with light including glare, and the various colors of light. These technologies determine whether or not the sunglasses are good for protecting or not. The following are the different technologies you can get in sunglasses:

• Tinting
• Polarization
• Photochromic lenses
• Mirroring
• Scratch-resistant coating
• Anti-reflective coating
• UV coating

All of these technologies are going to help protect your eyes, but one that you should try and understand is that of tinting.

There is a whole spectrum of colors, and the color of the tint determines the parts of the light spectrum that are absorbed by the lenses. Different tints protect the eyes in different ways.

Gray tints: These are usually all-purpose tints used to reduce the overall amount of brightness with the least amount of color distortion. So in other words, you can still see things as they are, but get protection as well. Gray tint lenses also offer the benefit of protection against glare. These are probably the most ideal sunglasses for driving and for general use.

Yellow or gold tints: These are usually best for reducing a kind of glare known as blue haze. The yellow tint eliminates the blue part of the spectrum and has the effect of making everything bright and sharp. It means you get clearer vision without the damage of glare. Thus this tint is best for use in high glare situations such as when out in snow. Buying ski and snowboard goggles with yellow or gold tint is a good idea. While the tint distorts color perception, they protect the eye well from glare, which makes them a great choice if you do not need to rely on accurate color.

Amber and brown tints: These are usually good general purpose tints. They are good at reducing glare, because in addition to UV rays, they have molecules that absorb higher frequency colors, such as blue, which is what causes glare. Thus, these are great sunglass lenses if you want to protect your eyes from possible problems like cataracts. These sunglasses distort colors, but they also increase contrast and clarity.

Green tints: These kind of lenses are best for filtering some blue light and reducing glare. They are popular because they offer high contrast and visual acuity. In other words, they are the best of any tint for filtering blue light. 

Purple and rose tints: These are great lenses for hunting or water sports such as water skiing because they block glare, and help you see contrast of objects against a green or blue backgrounds.

Usually manufacturers apply tint by using a glass or polycarbonate mixture with a uniform color throughout the material, meaning that the tint is built right into the lenses when they are created. However, some manufacturers get tint by applying a coat of light-absorbing molecules to the surface of clear polycarbonate. However, typically, the most common method for tinting polycarbonate lenses is to immerse the lenses in a liquid containing the tinting material. The tint is slowly absorbed into the plastic. For darker tinted glasses, lenses are left in the liquid for a longer period of time. 

The top sunglass manufacturers are as follows:

• Black Flys
• Bolle'
• Cebe
• Costa Del Mar
• Eyehawk
• Maui Jim
• Native Eyewear
• Oakley
• Ray-Ban
• Revo
• Serengeti
• Sexx Vision
• Shields
• Sun Tiger
• Vuarnet

Sunglasses should be purchased in order to protect your eyes from the sun, but they can also be used as a fashion statement, an accessory, and a fun way to spruce up an outfit, or add some interest to your outfit. The fact is, sunglasses do not have to be all about the tint, polarization, UV protection, etc. they can be fun too, however, you do not want to forget to protect your vision.