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DISPLAYS · OPTICAL BONDING

What Is Optically Clear Adhesive (OCA)?

Optically clear adhesive (OCA) is a transparent, double-sided adhesive film used to bond a cover glass or touch panel to a display with no air gap. It is laminated with pressure, often in a vacuum, in the process called dry optical bonding. Its liquid counterpart, LOCA, is dispensed as a liquid and cured with UV light or heat.

01

The Short Answer

OCA replaces the air between the layers of a display with a clear material whose refractive index is close to that of glass. That removes the internal reflections an air gap causes, so the screen looks darker and sharper in bright light, and it stops condensation forming between the layers.

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    OCA (film) Pre-formed adhesive sheet; clean, consistent thickness; suits flat, small to medium displays.
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    LOCA (liquid) Dispensed liquid, cured by UV or heat; fills uneven gaps and suits larger or curved assemblies.
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    Both Index-matched to glass, highly transparent and designed not to yellow with age.
02

OCA in Industrial Displays

Industrial displays and panel PCs use OCA or LOCA to bond touch sensors and cover glass for outdoor, vehicle and marine use. Our guide to optical bonding compares dry and liquid bonding and explains where each fits.