Close Window

Polarised (Polarized) Lenses

The main advantage of polarised (polarized) lenses is that they eliminate glare as well as the reflected rays that bounce off flat or mirrored surfaces. This is particularly ideal for driving (even in cloudy conditions, as they remove the reflections seen on a windscreen) and also for many outdoor sports, such as fishing (allowing the wearer to see much clearer what is in the water), and for golf, cycling, ski-ing - in fact any outdoor activity where glare or reflected rays may hinder one's view.

Polarised lenses are also extremely beneficial for use indoors by people with light sensitive retinas, especially those that have undergone cataract surgery, and anyone that may be frequently exposed to bright sunlight through windows.

Sunglass Lenses

Lens Colour

The colour of the lens can vary by style, fashion, and purpose, but for general use, green, grey, yellow, or brown is recommended to avoid or minimize colour distortion which would be dangerous when, for instance, driving a car. Gray lenses are considered neutral because they do not enhance contrast or distort colours. Brown and green lenses cause some minimal colour distortion, but have contrast-enhancing properties. Red lenses are good for medium and lower light conditions because they are good at enhancing contrast but causes colour distortion. Orange and yellow lenses have the best contrast enhancement at depth perception but cause colour distortion. Yellow lenses are commonly used by golfers and shooters for its contrast enhancement and depth perception properties. Blue and purple lenses offer no real benefits and are mainly cosmetic

Mirrored Coatings

A mirrored coating can also be applied to the lens. This mirrored coating reflects some of the light when it hits the lens before it is transmitted through the lens making it useful in bright conditions. These mirrored coatings can be made any colour by the manufacturer for styling and fashion purposes. The colour of the mirrored surface is irrelevant to the colour of the lens. For example, a gray lens can have a blue mirror coating, and a brown lens can have a silver coating. Sunglasses of this type are sometimes called mirrorshades. A mirror does not get hot in the sunlight and prevents scattering in the lens bulk.

Lens Material

Sunglass lenses are made from either glass or plastic. Plastic lenses are typically made from acrylic, polycarbonate, or CR-39. Glass lenses have the best optical clarity and scratch resistance, but are heavier than plastic lenses. They can also shatter or break on impact. Plastic lenses are lighter than glass lenses, but are more prone to scratching. They do however, offer more resistance to shattering than glass. Polycarbonate lenses are the lightest, and are also almost shatterproof, making them good for impact protection. CR-39 lenses are the most common plastic lenses, due to their low weight, high scratch resistance, low transparency for ultraviolet and infrared radiation, and other advantageous properties.

Polarised Lenses

Some models have polarised lenses (made from Polaroid or a similar material) to reduce glare caused by light reflected from polarising surfaces such as water, as well as by polarised diffuse sky radiation (skylight). This can be especially useful when fishing, as the ability to see beneath the surface of the water is crucial.

Close Window