Which lens colour for better vision?
Ella Tan | On 29, Dec 2014
Clear lenses, with no colour-tint, can still be UV-light blockers, and they are very useful in protecting the eyes from impact, debris, dust, chemicals, or after eye surgery. Clear lenses can be used during low light or night-time activities, and are particularly effective to reduce glare under fluorescent light.
Most sunglasses come in a bewildering range of colours, from common amber and grey, to yellow, red, green, and even orange and plum. Does this mean, then, that the choice of colour is merely cosmetic? Absolutely not. Different colours absorb or transmit specific wavelengths of light. That is why, for example, when we look through red-coloured lenses, the world looks, well, rosy.
So when and why is the choice of colour important? Those of us with eye problems need to pay particular attention to these “colour codes” because by absorbing and transmitting certain specific wavelengths of light, tinted lenses – also called absorptive lenses – can improve our ability to see.
The two most commonly available colours for sunglasses are grey and amber. Grey lenses are described as neutral because they do not enhance contrast or distort colours. Choosing lighter shades of grey can help relieve indoor glare, especially under fluorescent light. In general, grey is soothing, sharpens focus, and provides good glare protection. Grey is often the colour of choice for post-op cataract surgery, glaucoma sufferers, diabetics or people who have had corneal transplants.
Amber tints are known for their “blue blocking”, protective effect. There is some evidence that the retina may be more sensitive to blue visible light. Blocking the visible blues eliminates much of the scatter created by the shorter wavelengths of light. The result is an apparent increase in contrast and depth perception. Objects appear more clearly defined, and thus amber tints are popular with skiers, boaters, and pilots. They also provide good contrast enhancement, useful for those with macular degeneration, and retinitis pigmentosa.