Advancements in three‐dimensional (3D) printing technology have the potential to transform the manufacture of customized optical elements, which today relies heavily on time‐consuming and costly polishing and grinding processes. However the inherent speed‐accuracy trade‐off seriously constrains the practical applications of 3D‐printing technology in the optical realm. In addressing this issue, here, a new method featuring a significantly faster fabrication speed, at 24.54 mm3h−1, without compromising the fabrication accuracy required to 3D‐print customized optical components is reported. A high‐speed 3D‐printing process with subvoxel‐scale precision (sub 5 µm) and deep subwavelength (sub 7 nm) surface roughness by employing the projection micro‐stereolithography process and the synergistic effects from grayscale photopolymerization and the meniscus equilibrium post‐curing methods is demonstrated. Fabricating a customized aspheric lens 5 mm in height and 3 mm in diameter is accomplished in four hours. The 3D‐printed singlet aspheric lens demonstrates a maximal imaging resolution of 373.2 lp mm−1with low field distortion less than 0.13% across a 2 mm field of view. This lens is attached onto a cell phone camera and the colorful fine details of a sunset moth's wing and the spot on a weevil's elytra are captured. This work demonstrates the potential of this method to rapidly prototype optical components or systems based on 3D printing.
Synergizing grayscale photopolymerization and meniscus coating processes, rapid 3D printing of optical lenses is reported previously using projection microstereolithography (PµSL) process. Despite its 14 000‐fold‐improved printing speed over the femtosecond 3D printing process, PµSL still consumes significant amount of the fabrication time for precise recoating 5 µm thick fresh resin layers. At the reported speed of 24.54 mm3h−1, 3D printing of the millimeter‐size lenses still takes hours. To further improve the printing speed, the microcontinuous liquid interface production process is implemented to eliminate the time‐consuming resin recoating step. However, the micrometer‐size pores in the Teflon membrane needed for oxygen transportation are found to completely spoil the surface smoothness. The use of polydimethylsiloxane thin film possessing much refined nanoscopic porosities as the functional substitute of Teflon membrane is reported to significantly reduce the surface roughness to 13.7 nm. 3D printing of 3 mm high aspherical lens in ≈2 min at a 200‐fold‐improved speed at 4.85 × 103mm3h−1is demonstrated. The 3D printed aspherical lens has the demonstrated imaging resolution of 3.10 µm. This work represents a significant step in tackling the speed‐accuracy trade‐off of 3D printing process and thus enables rapid fabrication of customized optical components.
more » « less- PAR ID:
- 10458540
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Optical Materials
- Volume:
- 8
- Issue:
- 4
- ISSN:
- 2195-1071
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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