3D‐Printed Holographic Fresnel Lenses

Additive manufacturing processes are capable of fabricating optical devices, including the production of contact lenses, waveguides, and Fresnel lenses used in a variety of applications. This study presents a novel fabrication method for high‐quality Fresnel lenses through a vat photopolymerization 3D printing method. Here, the 3D printing process is integrated with the micro/nanostructure fabrication to produce 3D optical components with imprinted micro/nanostructures in a single step. This straightforward approach allows imprinting a micro‐pattern (5 μm features size) onto the flat surface of a 3D‐printed Fresnel lens, achieve light focusing properties along with holographic rainbow effects. The printed lenses achieve focal lengths within ≤8 mm deviation from the predicted values. Such holographic Fresnel lenses are highly desirable in imaging‐based miniature spectrometers for mechanoluminescence sensoring. Thus, the masked stereolithography (MSLA) based 3D printing process can produce normal and holographic Fresnel lenses, vital in optical sensing and communication. A novel 3D printing/microimprinting hybrid fabrication process has been proposed for multi‐unctional optical devices, particularly Fresnel lenses. The rainbow hologram is due to the micropattern features embedded during printing. The Fresnel rings produce a lens effect, using focusing light in the background. The hybrid process improves the optical properties of the Fresnel lens for image‐based sensing applications.