As a cyclist, I know for a fact that the glare is the most debilitating element on the road for a biker. Since swapping my non-polarised pair of shades with polarised ones, I have developed a new confidence while riding. Potholes are easier to spot and reflections through glass and water are not a hindrance anymore. With clear viewing, I no longer have to squint and exert myself while riding my bike. Now the question arises, how polarised sunglasses are so much better than their non-polarised counterparts.

Difference between Polarised and Non-Polarised Sunglasses

Non-polarised sunglasses block out harmful UV rays, but do not have any polarisation capability. These glasses do not block the reflected light from smooth surfaces. On the other hand, polarised sunglasses cut through reflective glare and provide a clear and comfortable viewing experience. The mechanism behind the working of polarised sunglasses can also be understood by understanding the physics of the light waves.

Physics of Light Waves and Polarisation

Without taking you back to school I would like to shed some light on the concept of light waves. Light waves are "transverse waves," which basically means that the particles of the wave move at right angles to the direction in which the wave is moving. When polarisation occurs, i.e. when the up-and-down oscillation of light waves is reflected from non-metallic surfaces, they oscillate in a back-and-forth motion after being reflected. This change is seen when you are not wearing polarised glasses. When you wear polarised glasses, this change is countered and your vision does not get hampered.

Polarised lenses utilize a filter with a vertically-oriented transmission axis and allow the unpolarised light waves, which are oscillating up-and-down, through them. The polarised, glare-creating light waves which are oscillating back-and-forth are blocked. The molecular structure of a polarised lens filter is like a fence or a shutter, which can only allow unpolarised light through it. The back-and-forth movement of glare-causing polarised light gets blocked at the "shutter" of the filter, which helps in reducing the glare effect.

Benefits of Polarised Sunglasses

The main advantage of wearing polarised sunglasses is that they provide a more comfortable visual experience. It also provides a far more defined field of vision and allows you to see objects in sunny or brighter conditions. You also get an enhanced perception of colour, which allows you to differentiate between the different colours more easily.

Fishermen and boaters love polarised sunglasses as these glasses allow them to see into the water with ease. As the water surface reflects everything around it, the view into the water gets obscured completely. Polarised lenses block these reflections and enable the person wearing the glasses see through the water and not in the reflected sky.

Disadvantages of Polarised Sunglasses

Despite their many benefits, polarised sunglasses have a few negative points as well. Polarised sunglasses are not good for reading from LCD and LED displays, as they end up blocking that light as well. Students, computer operators, and pilots who frequently have to read from LCD displays should avoid use of polarised sunglasses. Even when using a cell phone, it is better to take off your polarised sunglasses for a comfortable reading experience.

Brands to Buy

Polarised sunglasses are made available by many famous brands. A few of my favourites include: Costa, Native Eyewear, and Oakley. Polarised sunglasses from these sellers are of the highest quality and make for a great viewing experience with reduced strain. The stamp of quality provided by these brands comes with an assurance that your vision will not get hampered by the glare. Investing in a renowned brand is a great way to ensure safety.