Incoherent speckle imaging at the anisoplanatic limit
Prof. Jeremy Bos
Electrical and Computer Engineering Department
Michigan Technological University
Image or scene recovery at low signal levels and poor seeing presents a challenge for most adaptive optics systems. The problem is compounded when imaging man-made space objects in low orbits. Here, the turbulence changes quickly preventing loop-closure. When imaging over long horizontal paths in the atmosphere the problem is made worse: the isoplanatic angle can often be on the order of the diffraction limit. Incoherent speckle imaging is a post-processing technique that can often provide near diffraction-limited images in scene recovery tasks. In this talk, I will provide an overview of incoherent speckle imaging, why and where it is effective in the isoplanatic case and speculate on its effectiveness in “extreme anisoplanatism”. Part of this explanation involves the concept of “aperture partition” found to be useful in daylight imaging of space objects when the ratio of aperture size to the Fried coherence cell is large. Similarly, I reason that light-field approaches that exploit angular diversity may allow for joint estimation of the scene and volume turbulence. Potentially, this approach may allow for snapshot scene recovery and volume turbulence estimates.
Hosted by Prof. Crepp
Originally published at physics.nd.edu.