|1.56 Semi Finished Progressive(14mm) Lens|
Material: 1.56 Index Resin(Ne=1.56, Abbe=38, Specific Gravity=1.28)
Add Power: +1.00 to +3.50 in 0.25D steps
|CONVEX SURFACE||CONCAVE SURFACE|
|Mominal Curve||Actual Curve|
|Nominal Base Curve||Recommended Diopter in Base||Cylinder|
|3.00||-12.00 to -4.75||0~-6.00|
|4.00||-4.50 to +2.25||0~-6.00|
|5.00||+2.25 to +5.00||0~-6.00|
|6.00||+5.25 to +7.50||0~-6.00|
1) What are the progressive lens?
Progressive lenses are the most exciting and technologically advanced spectacle lenses available.
If you're a 40-something who has trouble reading fine print, you have more lens options than the old lined bifocals your parents wore. Progressive lenses, sometimes called "no-line bifocals," are multifocal lenses that eliminate the lines of a bifocal or trifocal lens. They look exactly like single vision lenses so nobody will know your arms have gotten too short to see small print!
They continue to increase in popularity and are now the most widely purchased lenses to correct presbyopia (the loss of near vision with age). Some people experience problems with progressive lenses when they try to adapt the first time or even to a new pair in a different frame and/or a different optical prescription.
2) Advantages of Progressives vs. Bifocals.
Progressives provide a more natural correction of presbyopia than bifocals or trifocals. They are considered "multifocals" because there is a seamless progression from distance to near with an intermediate section in between. This provides many focal points in order to satisfy almost any visual need.
There is a corridor that runs vertically down the middle of the lens and measurements will be taken to fit the corridor in the right place so all powers can be accessed comfortably.
3) Adjusting to Progressive Lenses
Patients must learn about progressive lenses so they can understand how to use them and what to expect.
Remember to point your nose directly at what you want to see. Then raise or lower your chin until the object comes into the best focus.
You may feel an initial difference in peripheral vision that will require some slight changes in horizontal head and eye movement. This will diminish with wearing time. Most people will adapt in a few hours although some can require as long as two weeks. If you are not adapted within two weeks you should return for a consultation with the optician that fitted your eyeglass frames to your face.
|The most important benefits of anti-reflective (AR) coating may be the unseen advantage–relief from fatigue and eyestrain caused by glare. AR does have a big cosmetic advantage, but removing the distracting reflections and ghost images that contribute to eyestrain clearly is a bigger benefit. Being more comfortable in anything we do is a benefit, especially when wearing glasses.|