Recently we developed and tested different algorithms for wave front reconstruction from dense Hartmann-Shack patterns. All depend on the recognition of a main frequency in the patterns, whose distortion from wave aberrations can be construed as slight phase changes in the pattern. An alternative description of these aberrations is a slight frequency change in Fourier domain. The slopes can thus be found by demodulation in either the image or the Fourier domain. These slopes can then be integrated in the Fourier domain again for the wave front itself. For smooth slopes both demodulation and integration can be performed in the Fourier domain. In addition, commands for the adaptive optics loop can be taken directly in the Fourier domain, saving on processing time. We modeled and tested these algorithms thoroughly in simulation and in laboratory experiments on two separate adaptive optics systems.
Anybody can mount a zooming lens on his camera and observe distant objects. FarAway penetrates the blanket of haze that obscures such objects, regardless of the origin - mist, smoke, dust, rain, aerosols, etc. The system works with live Video, 25 frames/second, performing the restoration in real time on a PC hardware. No pre-knowledge about the obscurants, targets or distances is required. The novelty lies in performance; the system does not use image-processing tricks or contrast-stretching, but rather restores the original true image with its true colors. The current version is capable of relative-contrast enhancement of up to 90 times in color and up to 130 in B/W or NIR, the limit dictated by electrical noise. Facing the sun, this means a three-fold and more increase in detection and recognition ranges. Both color and NIR systems were extensively and successfully tested under rain, mists, haze and dust storms at ranges from 0.2 to 65 km. Turbulence effects are treated crudely, reducing apparent turbulence dance and smear by a factor of 2 to 4. Tests have proved its superiority over existing top-rank military systems. A related technology is Very Far Away. While Far Away uses commercial as-is cameras, the Very Far Away uses a specially designed color camera. The special camera allows extension of the visibility range by a further 70%.