3D objects with features spanning from microscale to macroscale have various applications. However, the fabrication of such objects presents challenges to additive manufacturing (AM) due to the tradeoffs among manufacturable feature resolution, maximum build area, and printing speed. This paper presents a projection‐based AM process called hopping light vat photopolymerization (HL‐VPP) to address this critical barrier. The key idea of HL‐VPP is to synchronize linear scanning projection with a galvo mirror's rotation. The projector moves continuously at a constant speed while periodically rotating a one‐axis galvo mirror to compensate for the projector's linear movement so synchronized hopping motion can be achieved. By this means, HL‐VPP can simultaneously achieve large‐area (over 200 mm), fast‐speed (scanning speed of 13.5 mm s‐1), and high‐resolution (10 µm pixel size) fabrication. The distinguishing characteristic of HL‐VPP is that it allows for hundreds of times lower refresh rates without motion blur. Thus, HL‐VPP decouples the fabrication efficiency limit imposed by the refresh rate and will enable super‐fast curing in the future. This work will significantly advance VPP's use in applications that require macroscale part size with microscale features. The process has been verified by fabricating multiple multiscale objects, including microgrids and biomimetic structures.
While vat photopolymerization has many advantages over soft lithography in fabricating microfluidic devices, including efficiency and shape complexity, it has difficulty achieving well-controlled micrometer-sized (smaller than 100 μm) channels in the layer building direction. The considerable light penetration depth of transparent resin leads to over-curing that inevitably cures the residual resin inside flow channels, causing clogs. In this paper, a 3D printing process — in-situ transfer vat photopolymerization is reported to solve this critical over-curing issue in fabricating microfluidic devices. We demonstrate microchannels with high
- NSF-PAR ID:
- 10362928
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 13
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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