Optical properties of 3D printed reflective and transmissive components for use in LED lighting fixture applications

The abundance of commercial LED lighting fixtures in the marketplace has resulted in price erosion, forcing manufacturers to look for ways to lower manufacturing costs. 3D printing holds promise for providing new solutions that not only can increase the value of lighting but can potentially reduce costs. During the past few years, 3D printing has been successfully adopted in industries such as aerospace, automotive, consumer products, and medical for manufacturing components. For the lighting industry to adopt 3D printing for fabricating light fixtures, it has to show that different subcomponents of an LED light fixture, including thermal, electrical, and optical components, can be successfully made. Typically, optical components are either transmissive or reflective type. In both cases, the component's optical properties affect fixture efficiency and beam quality. Therefore, the objective of this study was to understand how short-term and long-term optical properties are affected when using 3D printed optical components. In the case of transmissive optics, several optical elements were printed and aged at higher than ambient temperatures and their corresponding spectral transmissions were measured over time. Similarly, several reflective optical elements were printed and characterized for spectral reflectivity as a function of print parameters, including print layer height, print orientation, and the number of print layers before and after aging the parts at higher ambient temperatures. These results are useful for optical component manufacturers to understand the possibilities of using 3D printing to make high-quality optics for lighting fixture applications and for 3D printing material and printer hardware manufacturers to understand the requirements of optics for the illumination applications.