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Conventional microscale 3D printing techniques mostly rely on the raster scanning method, which needs constant changing of printer head/light beam/substrate directions to print a solid structure. Therefore, throughput is a longstanding bottleneck and it is more challenging to print microfeatures in large areas. This study demonstrates the possibility of 3D printing microfeatures on a fast-spinning disc. A Blu-ray drives based high-throughput 3D printer (BRIGHT3D) is developed to demonstrate the spin printing on disc concept and evaluate the highest linear printing speed. The BRIGHT3D integrates two Blu-ray drives that are synchronized by a customized controller. The printing substrate is a standard Blu-ray RW disc spun by a spindle motor. Both drives utilize the same optical pick-up unit (OPU), which equips a voice coil motor (VCM) for the disc wobbling compensation. The bottom OPU detects the disc wobbling and feeds the VCM control signal back to top OPU for maintaining laser (405 nm, 658 microwatts) focused on the spinning substrate disc. The BRIGHT3D can directly spin-coat (up to 6,440 rpm) commercial photopolymers with a controllable thickness on top of the substrate disc. The top OPU laser was switched with a frequency of 1~500 kHz (duty cycle: 80 %) for the preliminary spinning 3D printing evaluation. Microfeatures can be cured by the BRIGHT3D while the disc is spinning at a speed of 265 rpm, which has a linear speed from inner diameter, 20 mm, to the outer diameter, 58.5 mm, of 0.55~1.63 meters per second. After removing the photopolymer residues by 75% ethanol, various microscale features on the disc can be seen and measured by scanning electron microscopy. Microscale lines (height/width: 1.43/8.25 microns) and dots (length: 5.97 microns) were successfully printed on the disc. The BRIGHT3D is aiming for multiple layer printing on the disc to realize sophisticated features of high-throughput 3D printing in the near future.
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