Additive manufacturing of photoluminescent optics

Additive Manufacturing (AM) is full of opportunities when it comes to fabrication of optical elements whether it be manufacturing complex design systems or precise fabrication of micro structures. In addition, there exists the possibility of introducing optical properties of interest (e.g. photoluminescence) or altering already existing properties (e.g. refractive index) of elements, with the corresponding alteration of raw materials used for fabrication. This possibility is being explored in our research group, to produce optical elements that can be 'activated' with respect to a specific property. Our current focus is on the introduction of narrow spectrum photo-luminescence of different wavelengths emitted simultaneously from a single 3D sample. Previously, we demonstrated the use of a photopolymer matrix embedded with quantum dots capable of emission in a specific wavelength, as the raw material to fabricate monolithic samples using DLP based 3D printing system. In this paper, we present the first 3D printed model that includes four different quantum dots in different spatial locations within the sample (printed with multiple quantum dot mixtures), capable of generating photoluminescence simultaneously in four different wavelengths in response to ultra violet excitation. Analysis was done to investigate the effect of nanocomposite mixture variations, printing, and photoluminescence from the samples, in terms of wavelength and emission intensity. The nanocomposites used for manufacturing the prototype were synthesized with a unique hydrophobic resin matrix (ORMOCER®) embedded with quantum dot nanoparticles.