|Don's Home Products Sunglasses|
Note: Much of the information below also applies to ski goggles.
Hiking, backpacking, mountaineering sunglasses.
Color: (Numbers in [ ] are transmission level.
UVA (320-400 nm)
UVB (290-320 nm)
UVC (200-290 nm)
See light under technology
Sources: Sunglasses 101 at HeavyGlare.com |
Color Analysis at SportsVisison.com|
Smith from store.yahoo.net (click for larger image)
Numbers are % light transmission
|Classic G-15 tint, which is a combination of gray and green. It is the original tint that Bausch & Lomb used in their Ray-Ban Aviator sunglasses for pilots. It is still popular.|
Oakley Tints at RubensMenswear |
Choosing Ski Goggles at SimplyPiste.com
A table for Smith Tint at backcountryoutlet.com had the following. The site is not available now and I couldn't find the information on Smith's page.
Visual light transmission (VLT) recommendations.
Oakley Lens Tints Explained
Glacier glasses (special sunglasses designed specifically to protect your eyes from the intense light at high altitudes) have a VLT/LTF of around 4-10%. Most glacier glasses also have shields to protect your eyes from light coming in from the sides of your lenses. Glacier glasses should not be used for driving or other everyday activities.
How Do I Clean My Sunglasses?
AAO: American Academy of Ophthalmology
AR: Anti-reflective (coating)
EPF: Eye Protection Factor - In 2004 EPF was proposed to be to non-prescription sunglasses what the Sun Protection Factor (SPF) is to sunscreen. It is an index from 1-100 proposed by Dr. Gary Hall, M.D. Phoenix, AZ. The EPF rating is based on frame coverage, ultra-violet (UV) protection, blue light protection and infrared protection, or the ability to shield the eyes from heat. The final EPF rating is a result of averaging the scores of these four factors known by the acronym FUBI. As of 2011 it had not seen widespread usage.
The Australian radiation protection and Nuclear Safety Agency (ARPANSA) has an EPF scale from 1 - 10 with 9 and 10 blocking most UVR.
HEV - High energy visible light (wavelength = 500-380 nm)- Recent research indicates that Blue-Violet (HEV) light might contribute to macular degeneration, or loss of vision detail.
Photochromic lenses (Transitions™ was one of the first companies to offer it in 1991) lighten or darken in response to sunlight's intensity.
They don't work when driving a car (UVB rays do not penetrate your windshield).
The Transitions™ lens designed to work behind the car windscreen has transmission levels of 35% - unactivated, 22% - in the car, 12% in direct sunlight.
1. Transitions has 50% LTF behind a car windshield.
2. The Photochromic lenses on Oakley's web site are different models than the ones in their store.
They use Transitions® technology.
At lower temperatures the reaction speed is slower, but the lenses darken further. Conversely, at higher temperatures, the reaction time is quicker, but the lenses do not go as dark.
Polarization: Blocks glare from reflective surfaces. These lenses are ideal for water sports, bicycling, and driving.
A Dell LCD computer display, iPhone, iPod nano and touch and a gas station LCD blacked out with the sunglasses at a 45° angle (actually 39° according to one article) but was only slightly reduced otherwise.
"Common techniques of incorporating polarization films into lenses by lamination (using adhesive to sandwich the film between lens layers) and drop forming (sandwiching then heating and pressing over contoured forms) can cause haziness and optical distortion. Oakley uses an injection-moulding process to infuse the lens material around the filter. This liquid fusion creates bonding at the molecular level."
Kaenon uses their SR-91 lens material for polarized lenses. It combines the crisp optical acuity of the finest glass lenses, in an ultra light weight, impact-proof lens. Kaenon Polarized SR-91 lenses have an optical acuity and clarity rating of "40" - the highest possible score in the stringent ANSI Z.87.1 testing regimen. They also have a Glare 86 Polarizing technology. See dpShop.ch
Pterygium - An abnormal mass of tissue arising from the conjunctiva of the inner corner of the eye that obstructs vision by growing over the cornea; it arises from irritation of the pinguecula (a slightly elevated elastic tissue deposit in the conjunctiva (a transparent lubricating mucous membrane that covers the eyeball) that may extend to the cornea but does not cover it.)
Visible Light (Red, Orange, Yellow, Green, Blue, Violet) 500 THz - 900 THz / 400nm to 700nm.
VLT - Visable Light Transmission: See LTF.
VTO - Visable Transmission: Optics - See Photochromic
Glossary of Eye Care Terms at AllAboutVision.com
An article at Science Museum of Minnesota's Science Buzz says:
See: Eyeglasses for lens materials
Lenscrafters and Pearl Vision offer a 30% discount for AAA
* Can get prescription lenses
I couldn't find any reviews. There are so many models and they change so much it would be difficult. Maui Jim and Kaenon were mentioned as high quality in a couple of forums.