Polarized Lenses – the good and the bad
What is polarized light.
Polarized light occurs when scattered light reflects off any flat horizontal shiny surface such as water in a lake, a car windscreen, sand, snow, concrete and asphalt roads. Glare or polarized light reduces visibility, distorts colour and makes vision uncomfortable and painful. It has not been shown to cause eye problems.
In theory polarized lenses should be better than plain lenses but in reality that is not always the case. Low quality polarized lenses can cause headaches, distort vision and lead to eye problems and blindness. Note that polarized lenses are no better or worse than plain lenses at eliminating harmful UV radiation, just make sure you only buy sunglasses with 100% UV protection.
How polarized lenses are made.
Low quality polarized lenses.
Really low quality polarized lenses are made from laminating the polarized film (a very soft PVA material that is heated and stretched to form long chain molecules, causing them to align in one direction) is then sandwiched between thin sheets of acrylic or acetate. These cheap polarized lenses scratch really easy and have distortion due to the thin lens distorting the polarized layer which causes headaches and eye fatigue, a common problem reported by many customers. Due to the distortion and low quality polarized sheet material used in these lenses they have been known to only cut as little as 30% of the reflected glare. These lenses should always be avoided, especially for children who are harder on sunglasses.
High quality polarized lenses.
High quality polarized lenses start with the same process of heating and stretching a soft PVA material to form long chain molecules, causing them to align in one direction. But done very accurately with high quality material so it can eliminate all polarized glare. This polarized sheet is then laminated between two high quality polycarbonate lenses or glass lenses. To avoid distortion of the polarized sheet the finished lenses should be around 2mm thick for polycarbonate. Don’t buy thinner lenses they will cause headaches and eye fatigue, a common problem reported by many customers. Of cause these high quality polarized lenses do cost more.
Eye sight is important and low quality polarized sunglasses that will damage eyesight cost similar to high quality plain lenses sunglasses that will protect eyesight. So buy the high quality plain sunglasses. If you can afford the high quality PC polarized sunglasses that will eliminate reflective glare, then buy these. To give you an indication of the price on high quality adult PC polarized sunglasses, these normally start at A$140.00 up to A$700.00 or higher depending on the brand. Our Idol Eyes Australia baby polarized sunglasses using the same high quality PC polarized lenses start at A$95.00 Any prices lower than I have indicated will only be low quality polarized and should be avoided if you care about eye health.
Myths about polarized lenses.
- Polarized lenses are made with a polarized coating. No, totally false.
- Polarized lenses cut more UV radiation than plain lenses. No, not necessarily. Polarization has nothing to do with UV radiation. (Polarized lenses help eliminate polarized light or glare.)
- Polarized sunglasses are better than plain sunglasses. No, it firstly depends on the quality. But if both are high quality, the polarized lens will eliminate that horrid glare.
If you have any questions or require more information about this or any other sunglasses related matters please contact us via our contact page.