White 1.499 Index Flat Top Bifocal Lenses Without Coating CR39 Material
Place of Origin: Jiangsu, China
Model Number: 1.499
Lenses Color: Clear, Clear
Vision Effect: Flat Top
Brand Name: kingway
Lenses Material: CR39
Coating: UC, HC, HMC
Packaging & Delivery
|Single package size||50X45X45 cm|
|Single gross weight||About 22kgs|
|Package Type||Inner: envelops;Outer: Carton; export standard or upon your design|
|Lead Time||Quantity(Pairs) 1 - 1000prs, 10days|
|Quantity(Pairs) > 5000prs, To be negotiated|
1.61/1.67 progressive shorter corridor 12+2mm optical lens
|Refractive index||Corridor Length||Coating||Abbe Value|
|Specific Gravity||Transmission||Monomer||Power Range|
|1.32||> 97%||CR39||SPH: 0.00~+-3.00 ADD: +1.00~+3.00|
1) The most popular fused bifocal today has a D-shaped near segment rotated 90 degrees so that the flat part of the "D" is facing up. For this reason, D-seg bifocals also are called "flat-top" (FT) or "straight-top" (ST) bifocals.
2) This is a D segment bifocal lens. It has the benefit that the optical centre of the near vision part of the lens i.e. the part of the reading area which gives the very best vision, is situated at the top of the reading portion. Also the widest part of the reading area is just below the dividing line, and is the part of the lens the wearer would use.
The Advantages Of Flat Top Lenses.
1) This is a very convenient type of lens that allows the wearer to focus on objects both at close range and far range through a single lens.
2)This type of lens is designed to enable viewing of objects in the distance, at close range and in the intermediate distance with corresponding changes in power for each distance.
--HC(hard coating): To protect the uncoated lenses from scratch resistance
--HMC(hard multi coated/AR coating): To protect the lens effectively from reflection, enhance functional and charity of your vision
--SHMC(super hydrophobic coating): To make the lens waterproof, antistatic, anti slip and oil resistance.