This document condenses the results obtained when 3D printing lenses and their potential use as diffraction gratings using Digital Light Processing (DLP), as an additive manufacturing technique. This project investigated the feasibility of using DLP additive manufacturing for producing custom designed lenses and gratings. DLP was identified as the preferred manufacturing technology for gratings fabrication. Diffraction gratings take advantage of the anisotropy, inherent in additive manufacturing processes, to produce a collated pattern of multiple fringes on a substrate with completely smooth surfaces. The gratings are transmissive and were manufactured with slit separations of 10, 25 and 50 μm . More than 50 samples were printed at various build angles and mechanically treated for maximum optical transparency. The variables of the irradiance equation were obtained from photographs taken with an optical microscope. These values were used to estimate theoretical irradiance patterns of a diffraction grating and compared against the experimental 3-D printed grating. The resulting patterns were found to be remarkably similar in amplitude and distance between peaks when compared to theoretical values.

Polyvinyl alcohol (PVA) films with embedded electrically-responsive liquid crystal (LC) ellipsoids were fabricated to develop a membrane coating featuring tunable roughness. Membranes (∼30 microns thick) were placed between opposing pieces of indium-tin oxide (ITO) glass, creating electrodes for creation of a uniform electric field. Applied voltages ranged from 0V–350 V, as films were observed using an optical microscope. Thin-film interference patterns were observed in various regions of each film and were measured. Contour plots of film displacement were created and showed elevations across the observed region. The area of the first dark fringe regions, assumed to be in contact with the top glass surface, were measured as a function of applied voltage. The maximum displacement of the film was estimated to reach 1.5 microns and the area in contacted with the top glass surface increased 127% between 0–350 V. Finite element modelling results illustrate the influence of polarity on the roughness of the film surface.