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| Coating Structure |
| If necessary, additional hard-coating, AR (anti-reflection) multi-coating, HMC+EMI coating and Hydrophobic (water proof) coating will be provided. Coating structure
is as follows. |
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| Ultrasonic Cleaning |
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| Hard Coating |
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After thorough preparation, the plastic lenses are given a hard protective coating by
dipping them into a polysiloxane lacquer. The lacquer is optimally matched to the base
lens and the coating structure, it is reinforced by nano-particles to increase hardness and
abrasion resistance.
Pencil hardness of non-tintable hard-coating is upto 7H; pencil hardness of color tintable
hard-coating is upto 6H. |
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| Hard Coating |
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| AR+EMI Coating |
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| Now, most ophthalmic lenses are given AR (anti-reflection) multi layer coating which is
applied in a vacuum deposition system, some lenses also come with Anti-EMI coating
(Electro Magnetic Interference Blocking). The multi layer, broad-band anti-reflection coating is applied in a vacuum coating machine. The coating provides optimum transparency
with very low residual reflection |
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| Transmission Characteristics of White Lens |
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Un-coated |
Single Layer AR Coated |
Multi Layer (MAR) Coated |
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| Transmission Rate |
92% |
96% |
99.2% |
| Light Loss |
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8% |
4% |
0.8% |
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| Hydrophobic Coating |
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| Hydrophobic coating is the last layer in coating package, it provides the lens an extremely smooth surface. This makes the lens extremely repellent to dirt, water and
easily to be cleaned. |
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