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YTCA's Anti-reflection coating technology

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Spin Coating

Spin coating is another method for applying solution-based AR coatings. In this case, the substrate is mounted horizontally on a rotating platform. The substrate then spins very rapidly and the coating solution is dispensed onto it. The high-speed rotation throws off most of the solution, leaving behind a thin, uniform coating. Coating thickness is precisely controlled by the rotational speed of the substrate: Faster rotation results in a thinner coating layer.

Diagram of the Spin-Coating Process

Benefits of spin coating include fast process time (only a few seconds per coating) and high uniformity over the surface of curved parts. Lenses with varying curvatures may be coated evenly and uniformly with minimal thickness variation or edge effects. However, spin coating can only be performed on one part at a time, in contrast to dip coating in which many parts may be processed simultaneously.

In applications where either spinning or dipping can be used, it may be logical to use spin-coating in low volume operations and dip-coating in high volume operations. Spin-coating's speed and low equipment cost may be most suited to small optical labs, for example, while large labs or lens manufacturing facilities may be more suited to dip-coating where large batches can be processed.

© 2008 YTC America Inc.