Fabrication of Free-Standing, Self-Aligned, High-Aspect-Ratio Synthetic Ommatidia.
Free-standing, self-aligned, high-aspect-ratio (length to cross-section, up to 15.5) waveguides that mimic insects' ommatidia are fabricated. Self-aligned waveguides under the lenses are created after exposing photoresist SU-8 film through the negative polydimethylsiloxane (PDMS) lens array. Instead of drying from the developer, the waveguides are coated with poly(vinyl alcohol) and then immersed into a mixture of PDMS precursor and diethyl ether. The slow drying of diethyl ether, followed by curing and peeling off PDMS, allows for the fabrication of free-standing waveguides without collapse. We show that the synthetic ommatidia can confine light and propagate it all the way to the tips.
Department of Materials Science and Engineering, University of Pennsylvania , 3231 Walnut Street, Philadelphia, Pennsylvania 19104, United States.
Brian M
BM
Jun
Department of Materials Science and Engineering, University of Pennsylvania , 3231 Walnut Street, Philadelphia, Pennsylvania 19104, United States.
Francesca
F
Serra
Department of Materials Science and Engineering, University of Pennsylvania , 3231 Walnut Street, Philadelphia, Pennsylvania 19104, United States.
Yu
Y
Xia
Department of Materials Science and Engineering, University of Pennsylvania , 3231 Walnut Street, Philadelphia, Pennsylvania 19104, United States.
Hong Suk
HS
Kang
Department of Materials Science and Engineering, University of Pennsylvania , 3231 Walnut Street, Philadelphia, Pennsylvania 19104, United States.
Shu
S
Yang
D007909:Lenses
free-standing; high-aspect-ratio micropillars; ommatidia; self-aligned; waveguides