The 3d printing concept of depositing or jetting droplets of material onto a substrate layer by layer is finding its way into a number of new applications. One company mentioned at the recent RAPID show as an innovator in 3d printing was LUXeXceL. The technology patented through this company combines digital printing, optics, and lighting, enabling designers to produce optical structures, lenses, and prisms by “printing” them on various backing materials.
Terry Wohlers of Wohlers Associates, Inc., mentioned LUXeXceL’s ‘Printoptical Technology’ as one of the ‘emerging’ additive manufacturing technologies at the trade show. Wohlers also included it in his “Wohlers Report 2012,” as part of the emerging technologies that “avoid complicated and costly conventional processes, such as injection molding, diamond turning, polishing and grinding, used to produce many types of optical components.”
The founders of LUXeXcel, CEO Richard van de Vrie, and CTO Kurt Blessing are the innovators of Printoptical Technology. Digital printing is combined with optics and lighting to print various objects, such as lenses for LEDs, lamps, and luminaires, replicas of stain-glass artwork, or brochures and other communication tools. For some applications, it gives a printed work a third dimension, such as a 3D business card or labels. Eventually, this technology could be used to print custom contact lenses. Printing optical structures on foils can also be used to increase the output of photovoltaic cells for converting solar radiation into electrical energy.
The material used is a transparent or tinted polymer. The equipment deposits droplets that have a resolution of 1400 pixels. As the equipment lays down a layer of the polymer, UV radiation cures it.
The equipment used to print these lenses is standard UV-inkjet equipment. This printer has the label “LUXeXceL inside,” referring to the proprietary technology used for depositing the polymer and curing it.
The print heads deposit the polymer material onto a substrate, usually glass, foil, or PMMA. The print head is piezoelectric controlled and delivers a resolution of 1,440 dpi for a jetted dot size of 18 μm and a droplet volume of 7 picolitre.
There is a slight time delay between jetting a bubble of polymer and applying the UV light. This delay is just enough to give the monomer material an opportunity to flow and lose its spherical form before curing. Part of van de Vrie and Blessing’s innovative work involved mastering this delay and flow technique.
Lenses can be printed with a refractive index of 1.5 using this approach.
The company’s objective is to offer manufacturing as a service.
LUXeXceL Group B.V.