Water-Repellent Lenses for Glasses
Do You Need Water-Repellent Lenses?
You’re out and it starts drizzling. The rain-drops cover your glasses and you have to clean them constantly - an annoyance you really don’t need! The same happens when you’re splashing in the pool with friends or even washing dishes when some water droplets land in the middle of your glasses. What’s a spectacle-wearer to do?
Luckily, there are water-repellent lenses, also known as hydrophobic lenses. 'Hydrophobic' means fear of water, a perfect name for such lenses.
Switching to such lenses can help avoid problems with water, rain, and sweat on our glasses, which can hinder our vision and slow down your work or just be plain annoying. You can see the same hydrophobic properties on the wings of different kinds of insects, and that is why a dragonfly can travel unhindered when it’s raining, as their wings are able to repel the water droplets with their hydrophobic coating.
What Are Water-Repellent Lenses/Coatings?
The water-repellent coatings of lenses like Crizal® prevent water droplets from sticking to the lens. This is achieved by having a slight angle to the lens that causes the water drops to slide down and off. The smaller the angle, the more effective the slide-off - the optimum angle being around six degrees. These lenses are ideal for people who wear their glasses all the time, as there are many situations in which water can obscure their vision.
How Does The Hydrophobic Coating Actually Work?
Imagine droplets of water running down a particular surface. In the case where there is more friction, the droplets spread somewhat and stick to the surface. But when there is less friction, inhibiting the water droplets to join and increase in size, they run down and off the surface. Water molecules are polar and tend to be attracted by other polar molecules, particularly other water molecules. Their hydrophobic properties create surface tension, and inhibit the surface from being covered – and so, therefore, when used on lenses, water is repelled.
When Would I Need Water-Repellent Lenses?
Water-repellent lenses can be useful for everyone who wears glasses, but particularly:
- If you work outside or perform outdoor activities that would increase your chances of being in the rain
- Parents bathing their children definitely face challenges with struggling infants and splashing
- Even washing your car with a high-pressure hose can often create a mist in the air and create droplets of water on your lenses
- If you’re an athlete and sweating hinders your performance as it sticks to your glasses and blurs your vision
There are so many activities or scenarios in which you can get your glasses wet, so having a water-repellent coating will save you the trouble of constantly cleaning it.
To find out what options you have for your glasses or how to get a pair of glasses that are water repellent, visit the nearest optician.
Annoyed by water droplets on your glasses?
Talk to an optometrist to learn more about water-repellent lenses today.