Sunglasses are available in many different sizes, styles and shapes. You also need to make a decision about the lens tint and lens colour when you pick out a pair of shades in a shop. Choosing sunglasses with red lenses is not simply a matter of style. Red-tinted lenses have an effect on your clarity of vision and how you see colours, resulting in performance benefits and disadvantages.
A red or pink lens tint on sunglasses affects your vision and in particular how you see the spectrum of colours. A lens with a pink or red tint blocks some blue light. This improves colour contrast, especially in low light conditions, which in turn can help improve visibility and enhance visual depth. Red and pink lenses reduce eye strain and are therefore comfortable to wear over a long period of time; however they are not suitable for wearing in very bright conditions.
Many people wear red-tinted lenses when taking part in sports. Red and pink lenses are good for cycling and racing because they improve road visibility. A red tint also helps skiers see in cloudy and low-light conditions because it enhances colour contrast. Red lenses make it easier to see objects against green or blue backgrounds, so they're useful to wear when taking part in shooting or archery, as well as when hiking in forests.
Wearing sunglasses when driving reduces the effect of glare and can prevent road traffic accidents, but some tinted sunglasses are not suitable for driving. If you're wearing red lenses when driving, the tint density should not be less than 8 percent during the day or less than 75 percent at night. According to 1991 research from the University of Waterloo in Ontario, Canada, 50 percent of sampled tinted lenses failed to meet requirements from the American National Standards Institute for viewing traffic lights and shifts in colour.
Red tinted lenses may be beneficial for people who suffer from retinitis pigmentosa, an eye disease that involves the retina. The red lens blocks blue light, resulting in vision improvements and decreased light sensitivity. Specsavers advise the red tint should be as dark as regular sunglasses lenses. Glasses with coloured filters, including red-tinted lenses, can help children who experience distortions when looking at text to read, according to the Eyecare Trust. Tinted glasses can also speed up reading and improve comfort. Red is not the only beneficial shade and children need to choose the most appropriate colour for their needs.