  Speckle imaging is a well known method to achieve diffraction-limited (DL)
imaging from ground-based telescopes. The traditional observing method for
speckle has been to observe a single, unresolved, source per telescope pointing
over a relatively small field of view (FOV). The need for large DL surveys of
targets with high sky density motivates a desire for simultaneous speckle
imaging over large FOVs, however it is currently impractical to attain this by
covering the entire focal plane with fast readout detectors. An alternative
approach is to connect a relatively small number of detector pixels to multiple
interesting targets spanning a large FOV through the use of optical fibers, a
technique employed in spectroscopy for decades. However, for imaging we require
the use of coherent fiber bundles (CFBs). We discuss various design
considerations for coherent fiber speckle imaging with an eye toward a
multiplexed system using numerous configurable CFBs, and we test its viability
with a prototype instrument that uses a single CFB to transport speckle images
from the telescope focal plane to a traditionally designed, fast readout
speckle camera. Using this device on University of Virginia's Fan Mountain
Observatory 40-inch telescope we have for the first time successfully
demonstrated speckle imaging through a CFB, using both optical and NIR
detectors. Results are presented of DL speckle imaging of well-known close
(including subarcsecond) binary stars resolved with this fiber-fed speckle
system and compared to both literature results and traditional speckle imaging
taken with the same camera directly, with no intervening CFB.
