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Jiangsu Aogang Optical Glasses Co., Ltd.

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1.56 Eyeglass Lens Blanks Flat Top Bifocal Vision AR Coating 1.28 Specific Gravity

1.56 Eyeglass Lens Blanks Flat Top Bifocal Vision AR Coating 1.28 Specific Gravity

    • 1.56 Eyeglass Lens Blanks Flat Top Bifocal Vision AR Coating 1.28 Specific Gravity
    • 1.56 Eyeglass Lens Blanks Flat Top Bifocal Vision AR Coating 1.28 Specific Gravity
  • 1.56 Eyeglass Lens Blanks Flat Top Bifocal Vision AR Coating 1.28 Specific Gravity

    Product Details:

    Place of Origin: China
    Brand Name: Aogang Optics
    Certification: CE/FDA/ISO9001
    Model Number: Flat Top Bifocal Lenses

    Payment & Shipping Terms:

    Minimum Order Quantity: 100 pairs
    Price: negotiation
    Packaging Details: 1) Standard white envelope 2) color envelop with customer's design
    Delivery Time: 10~30 days, depend on your quantity
    Payment Terms: T/T, Western Union, L/C, D/A, D/P, MoneyGram,Paypal
    Supply Ability: 40,000 pieces per day
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    Detailed Product Description
    Refractive Index: 1.56 Diameter: 70mm
    Abbe Value: 38 Specific Gravity: 1.28
    Transmission: 98% Coating: AR Coating
    Base: 2/4/6/8 ADD:: +100~+350

    1.56 Flat-top Bifocal AR Coating Semi Finished Lens Blanks For Near And Far Vision
     
    I. Technical Data:

     

    1.56 Semi Finished Flat Top Bifocal Lens Blanks

    Material: 1.56 Index NK55 Resin(Ne=1.549, Abbe=38, Specific Gravity=1.28)

    Segment Placement: 5mm down -5mm in

    Add Power: +1.00 to +3.50 in 0.25D steps

    Segment Size: 28mm

     

    CONVEX SURFACE CONCAVE SURFACE      
    Mominal Curve True Curve Sag(sagitta: 40mm) Sag(sagitta: 50mm) Radius Radius CT(mm) ET(mm) Dia(mm)
    1.549 1.530
    4.25 4.18 4.04 1.51 2.37 131.29 132.50 8.7 11.7 70
    6.25 6.25 6.03 2.27 3.57 87.87 88.80 11.3 8.8


    II. Flat top bifocal lens:

     

    1.56 Eyeglass Lens Blanks Flat Top Bifocal Vision AR Coating 1.28 Specific Gravity

    ----Segment Widths

     

    Bifocal lenses are available with one segment widths: 28 mm. The number after the "CT" in the product name indicates the segment width in millimeters. The diameter 28 mm provides correspondingly wider fields of view.

     

    ----Flat Top 28 Bifocal Lenses

     

    A flat top 28 bifocal lens is offers correction for both near and far distances. It is a multifocal lens commonly prescribed for those suffering from both presbyopia and hypermetropia, a condition whereby, with age, the eye exhibits a progressively diminished ability to focus on near and far objects. The flat top lens includes a segment at the lower half of the lens with a prescription for reading (near distance). The width of the flat top 28 bifocal is 28mm wide at the top of the bifocal and looks like the Letter D turned 90 degrees.

     

    Because the flat top bifocal is one of the easiest multifocal lenses to adapt to, it is one of the most popular bifocal lenses in the world. It's distinct "jump" from distance to near vision gives wearers two well-demarcated areas of their glasses to use, depending upon the task at hand. The line is obvious because the change in powers is immediate with the advantage being it gives you the widest reading area without having to look too far down the lens. It is also easy to teach someone how to utilize the bifocal in that you simply use the top for distance and the bottom for reading.

     

     III. Compared with CR39 1.499 flat top bifocals:

     

    Production flat top bifocal lens
    Index 1.499 1.56
    Monomer CR39 NK55
    Diameter/Segment 70/28mm 70/28mm
    Abbe value 56 38
    Specific Gravity 1.33 1.28
    Thickness   Index 1.56 lenses will be thinner than Index 1.499 lenses in the same diopters. As the        increase in diopters, the difference will be bigger.
    Weight   As the same prescription, the thickness is thinner, the lenses will be lighter.
    Transmittance   1.499 lens has the highest transmittance as compared with 1.56 lens.
    ABBE value   According to ABBE value, 56 is higher than 38, that means 1.499 biocal lens can              provide the more comfortable visual experience.

     

    IV. Production Process:

    1.56 Eyeglass Lens Blanks Flat Top Bifocal Vision AR Coating 1.28 Specific Gravity

    V. Packing:

     

    1. Envelope:

    a) standard white envelope

    b) color envelope with customer design (Weight: 157g, Size: 9*9*9cm)

     

    2. Outer Box

    a) standard export paper carton (Size: 38*48*35cm, 0.064CBMS)

    b) Include about 500 pairs of finished lens (Weight: about 21kg) or include about 100 pairs of 100 semi finished lens (Weight: about 15kg)

     

    VI. Shipping:

     

    1. Samples:

    a) Delivery time: 3-7 days (by Fedex, DHL, UPS, TNT etc.)

    b) Sample is free, but accroding to our company rule, the shipping cost need to be assumed by customers.

     

    2. Batch Goods:

    a) Delivery time: 10-30 days (depend on your quantity, by air, sea or express)

    b) Carrier: We can choose for you or offer us your cooperative company

    Contact Details
    Jiangsu Aogang Optical Glasses Co., Ltd.

    Contact Person: Irene Wang

    Tel: +8615896369076

    Send your inquiry directly to us (0 / 3000)

    Jiangsu Aogang Optical Glasses Co., Ltd.
    East of Nongangxiao, Situ Town, Danyang City, Jiangsu Province, China
    Tel:86-511-86550315-9:00~17:00
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