Polarized Sunglasses

[crazy charlie]

Re: Polarized Sunglasses

I wore Ray Ban for years and loved them until my wife and I bought each other pairs of Maui Jims.They are by far superior to any I have ever seen.Their customer service is great too.Mine developed a slight line in the top of the lens and they replaced the lens for the shipping cost only...no questions asked.Charlie

 

[Capn Mike]

Re: Polarized Sunglasses

Pakev, I wear eyeglasses with a fairly strong prescription, and, since I'm over 40, I need bi-focals as well.<br /><br />So I get clip-on polaroids. My criterea is they fit my eyeglasses, be light (so as to not add too much more weight), and not scratch too easily.<br /><br />Are clip-ons and quality contradictory?

 

[PAkev]

Re: Polarized Sunglasses

Originally posted by Capn Mike:<br /> Pakev, I wear eyeglasses with a fairly strong prescription, and, since I'm over 40, I need bi-focals as well.<br /><br />So I get clip-on polaroids. My criterea is they fit my eyeglasses, be light (so as to not add too much more weight), and not scratch too easily.<br /><br />Are clip-ons and quality contradictory?

Capn,<br /><br />Although it seems like the round about way, I promise to answer your question ... by comprehending some minor mechanics about light transmission, you should be able to also clearly understand the final answer.<br /><br />Every optical lens has what is known as an index of refraction. This is a ratio of the speed of ambient light through an optical lens compared to air. For instance the index of CR 39 plastic lenses is 1.49, meaning light passes through the lens material about half as fast as it passes through air.<br />Now since you indicated to have a significant visual deficit, it is realistic that a high index material has been used to manufacture your lenses in order to reduce thickness and weight to contribute better comfort. Here is where the problem arises: light is passing through the clip material at a slower speed than your prescription lenses need the light. Therefore, we would expect compromised optics with the clip alternative compared to polarized prescription sunwear. If you have been wearing a clip for many years it is possible your eyes have become tolerant of the distortion caused by this combination and I would expect you to notice an appreciable difference if you ever went the RX sunwear route which by the way are available in bifocal and no-line progressive designs. Even for folks with minor prescriptions, it is very unlikely the clip material index will match the RX lens material index exactly therefore resulting in some nominal & tolerable distortion. <br /><br />Clips are notorious for scratching lenses and unless you use the magnetic type which attaches directly to the frame, most generic clips end up scratching the lenses much sooner than later. Furthermore, all the clips I know of utilize the laminate polarization process (see my post above) of which a limited service life can reasonably be expected. We provide polarized prescription, clip, and fitover type sunwear in our optical shop with the last two being an inexpensive alternative to purchasing a dedicated pair of sunwear. Upon a comprehensive understanding of their options most of our patients opt for the dedicated RX sunwear.<br /><br />Hope this info helps you to SEE the difference!<br /><br />Kevin