  Miniature varifocal lenses are crucial for many applications requiring
compact optical systems. Here, utilizing electro-mechanically actuated 0.5-mm
aperture infrared Alvarez meta-optics, we demonstrate 3.1 mm (200 diopters)
focal length tuning with an actuation voltage below 40 V. This constitutes the
largest focal length tuning in any low-power electro-mechanically actuated
meta-optic, enabled by the high energy density in comb-drive actuators
producing large displacements at relatively low voltage. The demonstrated
device is produced by a novel nanofabrication process that accommodates
meta-optics with a larger aperture and has improved alignment between
meta-optics via flip-chip bonding. The whole fabrication process is CMOS
compatible and amenable to high-throughput manufacturing.
