3D Printing Microscale Hemispherical Lenses Using Projection Two Photon Lithography

Two photon lithography (TPL) is a nano/microscale additive manufacturing process that allows for 3D printing with fea- tures of 100nm. Projection two photon lithography (P-TPL) is a subset of TPL that allows for entire layers of a structure to be printed at a time. This allows for P-TPL to be roughly 1000 times faster than standard TPL without compromising the resolution. One of the things that can be 3D printed with this method are micro-optics. Creating a 40μm diameter hemi- sphere that had little to no deformities and is easily mass pro- duced was our goal. Settings during the P-TPL process that were altered to make these hemispheres include but are not limited to: how many laser pulses polymerizes a layer, how many layers are printed and the spacing in between them, and how dense a feature on the print is. The best combination of these settings was found to be 10 layers with 2μm spacing in between layers, 1 laser pulse per layer, and having all features inside the structure to be printed.