3D printing of composite reflectors for enhanced light collection in scintillation detectors

The present study deals with the fabrication of light-reflecting materials used in pixelated scintillator detectors. For the first time the reflecting surfaces for pixels of different sizes (from 0.8 to 3.2 mm) were obtained via low-cost DLP 3D printing technique. The material for the reflectors was the new composite of transparent ultraviolet light-cured resin and TiO2 as a light-scattering filler. It was observed that TiO2 showed better performance compare to other pigments such as BaSO4, hBN or cubic zirconia. The reflectors formation rate was about 1 cm per hour with the possibility to produce several units simultaneously that simplifies the wrapping procedure. It was found that the regular pattern of the fabricated reflectors (stair-steps effect) could increase a light collection from a scintillator. The reflective properties of such surfaces were comparable to conventional reflection coating (e.g., Teflon wrapping).