Wetting Effect and FDM/FFF

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The reason why regular 3D printers cannot produce functioning optics is due to the fundamental way a 3D printer constructs its components - in cured layers. When these layers are fused together they form borders in between them.

One of the necessary requirements for a functional optical component is that light must be able to travel through it without being interrupted. The borders existing in traditionally 3D printed components scatter light.

This is not to say that 3D printers can't produce shapes that resemble lenses, in fact they can create components that look like perfect lenses, but they won't work like a lens.

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Another necessity for lenses is that they must have a smooth surface, criterion that the layering system again can not satisfy.
The Solution

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Printoptical© exploits the natural flow of liquids to avoid the bordering between layers. When two droplets of liquid touch each other, they join together to become a larger droplet. It was this principle that inspired LUXeXceL to develop a 3D print head that is able to place droplets in very specific places.

Utilising a UV curable clear polymer, LUXeXceL's 3D printer jets droplets into place and then waits for them to naturally combine, before applying the UV light to cure the lens. This avoids the issue of bordering which has haunted conventional attempts to create lenses via 3D printing and perfectly clear products are able to be manufactured.