Refractive index and dispersion of transparent 3D printing photoresins

The refractive index of commonly used 3D printing photosensitive resins were measured across the visible spectrum for s- and p-polarized light for the first time. Commercially available resins (Monoprice Clear and formlabs Clear) and a custom polyethylene glycol diacrylate photopolymer resin was characterized using a critical angle determination method with a Pulfrich-based refractometer setup. The refractive indices ranged between 1.505 − 1.533 across the visible spectrum (670 − 405 nm, respectively), while the Abbe number ranged between 44.4 − 67.8.