News - Lenses for middle-aged and elderly people

What is presbyopia?

"Presbyopia" is a normal physiological phenomenon and is related to the lens. The crystalline lens is elastic. It has good elasticity when it is young. The human eye can see near and far through the deformation of the crystalline lens. However, as the age increases, the crystalline lens gradually hardens and thickens, and then the elasticity is weakened. At the same time, the contraction ability of the ciliary muscle decreases. The focusing energy of the eyeball will also decrease, and the accommodation will decrease, and presbyopia occurs at this time.

What are adult progressive lenses?

The lenses we generally wear are ordinary monofocal lenses, which can only see far or near. On the other hand, adult progressive lenses have multiple focal points, with the upper part of the lens used for distant vision and the lower part used for near vision. There is a gradual transition from the distance power above the lens to the near power below the lens through a gradual change in refractive power.

Progressive lenses sometimes are called "no-line bifocals" because they don't have this visible bifocal line. But progressive lenses have a significantly more advanced multifocal design than bifocals or trifocals.
Premium progressive lenses (such as Varilux lenses) usually provide the best comfort and performance, but there are many other brands as well. Your eye care professional can discuss with you the features and benefits of the latest progressive lenses and help you find the best lenses for your specific needs.

The power of progressive lenses changes gradually from point to point on the lens surface, providing the correct lens power for
seeing objects clearly at virtually any distance.
Bifocals, on the other hand, have only two lens powers — one for seeing distant objects clearly and a second power in the lower
half of the lens for seeing clearly at a specified reading distance. The junction between these distinctly different power zones
is defined by a visible "bifocal line" that cuts across the center of the lens.

Progressive Lens Benefits

Progressive lenses, on the other hand, have many more lens powers than bifocals or trifocals, and there's a gradual change in power from point to point across the surface of the lens.

The multifocal design of progressive lenses offers these important benefits:

* It provides clear vision at all distances (rather than at just two or three distinct viewing distances).

* It eliminates bothersome "image jump" caused by bifocals and trifocals. This is where objects abruptly change in clarity and apparent position when your eyes move across the visible lines in these lenses.

* Because there are no visible "bifocal lines" in progressive lenses, they give you a more youthful appearance than bifocals or trifocals. (This reason alone may be why more people today wear progressive lenses than the number who wear bifocal and trifocals combined.)

Post time: Oct-14-2022