What are the different lens types?
Photochromic lenses: Photochromic lenses darken when exposed to direct sunlight and fade to virtually clear when not exposed to direct sunlight. We use only Transitions brand photochromic lenses, as they get darker / lighter / faster. Pro: the lenses adapt to the brightness without your having to do anything. Con: the lenses do not change much in a car, because you are in the shade or the UV light that activates the lenses is filtered by the windshield, and they take 5 to 7 minutes to fade when you move out of the sunlight.
Lined Bifocals: Lined bifocal lenses have a sharp demarcation separating the areas that correct for different distances (typically Distance Vision – 5 feet and further away - over the line and Near vision – 16 to 20 inches) under the line. Pro: the lenses have a large, clearly defined Near Vision portion and outside the Near portion is all Distance Vision. Con: People will see the line, and Intermediate Vision (20 inches to 30 inches) will be blurry.
Invisible Progressive Addition Lenses: Progressive Addition Lenses have no visible line. Distance Vision is directly in front of your eyes when in a Distant Relaxed Gaze, and the lenses power progresses to near vision as your eyes move down the lens. Pro: any distance is visible through the appropriate area of the lens. Con: near vision is narrow, and vision is never as clear at the edges as it is straight ahead.
Polarization: Polarization is a type of sunglass lens that blocks glare. Pro: the blinding glare reflecting off of the surface of water or car hoods and windshields is virtually eliminated. Con: it is difficult to read some electronic screens.
Anti-reflection coating: An Anti-reflective coating makes lenses look clearer and reduces halos and streaks from point sources of light when driving at night. We use only a hydrophobic and oleophobic coating, which resists smudging and is easier to clean. Pro: Looks nice, improves vision when driving at night. Con: Must be cleaned properly or it will smudge and / or scratch.
Polycarbonate material: Polycarbonate is a lens material that is thinner and lighter weight than regular plastic lenses, is 100% UVA and UVB protestive, and is the safest, most impact resistant lens on available today. We use Polycarbonate as our base material. Pro: thin, light, UV protective, extra impact resistant. Con:
High Index Lens Material: Hi-Index is a thin, light lens material – thinner and lighter than polycarbonate. It is recommended for stronger prescriptions to reduce the weight and thickness of the lenses. Pro: Thinner and lighter lenses. Con: higher priced