Wholesale Multifocal Lens Manufacturers – Bifocal Lens – YOLI
Wholesale Multifocal Lens Manufacturers – Bifocal Lens – YOLI Detail:
How to Tell If You Need Bifocals
Presbyopia is an age-related condition that results in blurry near vision. It often appears gradually; you will struggle to see a book or newspaper up close and will naturally move it further away from your face in order for it to appear clearly.
At around the age of 40, the crystalline lens within the eye loses its flexibility. When young, this lens is soft and flexible, easily changing shape so it could focus light onto the retina. After age 40, the lens becomes more rigid, and cannot change shape as easily. This makes it harder to read or do other close-up tasks.
Bifocal Lenses
Bifocal eyeglass lenses contain two lens powers to help you see objects at all distances after you lose the ability to naturally change the focus of your eyes due to age, also known as presbyopia. Due to this specific function, bifocal lenses are most commonly prescribed to people over the age of 40 to help compensate for the natural degradation of vision due to the aging process.
Three Designs of Bifocal Lenses
Regardless of the reason you need a prescription for near-vision correction, bifocals all work in the same way. A small portion in the lower part of the lens contains the power required to correct your near vision. The rest of the lens usually is for your distance vision. The lens segment devoted to near-vision correction can be of three shapes:
Shape 1
The Flat Top is regarded as one of the easiest multifocal lenses to adapt to, hence it is the most commonly used bifocal (FT 28mm is referred to as the standard size). This lens style is also one of the most readily available in almost any medium and including comfort lenses. The Flat Top utilizes the complete width of the segment giving the user a definitive reading and distance transition.
Shape 2
As the name suggests the round bifocal is round at the bottom. They were originally designed to help wearers reach the reading area more easily. However, this reduces the width of near vision available at the top of the segment. Because of this, round bifocals are less popular than the flat-top bifocals.The reading segment is most commonly available in 28mm.
Shape 3: Blended
The segment width of the Blended bifocal is 28mm. This lens design is cosmetically the best looking lens of all the bifocals, showing virtually no sign of a segment. However, there is a 1 to 2mm blending range between the segment power and the lens prescription. This blending range has a distorted perspective that can prove to be non-adaptable for some patients. However, it is also a lens used with patients that are non-adaptive to progressive lenses.
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We normally believe that one's character decides products' quality, the details decides products' high-quality ,while using the REALISTIC,EFFICIENT AND INNOVATIVE staff spirit for Wholesale Multifocal Lens Manufacturers – Bifocal Lens – YOLI , The product will supply to all over the world, such as: Sacramento, Brasilia, Cologne, Satisfaction and good credit to every customer is our priority. We focus on every detail of order processing for customers till they have received safe and sound solutions with good logistics service and economical cost. Depending on this, our solutions are sold very well in the countries in Africa, the Mid-East and Southeast Asia.
By Johnny from Bolivia - 2017.05.21 12:31
This company has the idea of "better quality, lower processing costs, prices are more reasonable", so they have competitive product quality and price, that's the main reason we chose to cooperate.
By Moira from Russia - 2017.09.16 13:44
