Optical bonding – more and more often you can read about this topic in publications, blogs or brochures. But what exactly describe these two words?

Optical bonding is an adhesive technology to connect components like displays in a high-quality manner, with the result of increased display performance suitable for outdoors. That means, for example, that the screen must be readable and in particular under difficult conditions like direct sunlight. To reach this result, special transparent adhesives are used allowing for higher contrast and brilliance of the screen display.

A must for displays used outdoors, like excavators, pavers or milling machines. Readability is not the only advantage; its ruggedness is another one. Panels with optical bonding are highly suitable for use on construction sites, where dust, rain, heat and vibrations can have an unfavorable impact on all parts of the machine, also the control panels. Another advantage of optically bonded displays is that condensation is reduced as moisture cannot penetrate.

For an optimized result, it is important to use the appropriate adhesive. Most common are silicone, epoxy and polyurethane.

Silicone has a lot of advantages like thermal stability, low conductivity, chemical reactivity, as well as water tightness. It is also easy to rework as it is a rather soft material. But one big disadvantage is that if the bonds are rubbed during handling, often dirt enters. So the edges must be covered.

Epoxy is stiffer, but in contrast to silicone, cannot be reworked, which is a big disadvantage of this material.

The third possibility, polyurethane often gets yellow when it is in contact with light for a longer time, so it became more and more irrelevant as an adhesive.

Besides the adhesive, the bonding process is decisive for an optimal result, because air inclusions have to be prevented in any way.

In summary, optical bonding is a technique that needs know-how and expertise to be performed properly! If applied the right way, the result is stunning, especially if used in outdoor applications.

For more information, also read the following article: Optical bonding