  Giant exoplanets on 10-100 au orbits have been directly imaged around young
stars. The peak of the thermal emission from these warm young planets is in the
near-infrared (~1-5 microns), whereas mature, temperate exoplanets (i.e., those
within their stars' habitable zones) radiate primarily in the mid-infrared
(mid-IR: ~10 microns). If the background noise in the mid-IR can be mitigated,
then exoplanets with low masses--including rocky exoplanets--can potentially be
imaged in very deep exposures. Here, we review the recent results of the
Breakthrough Watch/New Earths in the Alpha Centauri Region (NEAR) program on
the Very Large Telescope (VLT) in Chile. NEAR pioneered a ground-based mid-IR
observing approach designed to push the capabilities for exoplanet imaging with
a specific focus on the closest stellar system, Alpha Centauri. NEAR combined
several new optical technologies--including a mid-IR optimized coronagraph,
adaptive optics system, and rapid chopping strategy to mitigate noise from the
central star and thermal background within the habitable zone. We focus on the
lessons of the VLT/NEAR campaign to improve future
instrumentation--specifically on strategies to improve noise mitigation through
chopping. We also present the design and commissioning of the Large Binocular
Telescope's Exploratory Survey for Super-Earths Orbiting Nearby Stars
(LESSONS), an experiment in the Northern hemisphere that is building on what
was learned from NEAR to further push the sensitivity of mid-IR imaging.
Finally, we briefly discuss some of the possibilities that mid-IR imaging will
enable for exoplanet science.
