SBIR-STTR Award

Filamentation of ultra-short laser pulse propagation in non-linear media offers significant potentials allowing to address numerous problems in military and commercial sectors. However, practical implementation of this requires an ability to control the USLP at its propagation through inhomogeneous media, like turbulent atmosphere. On the basis of our approach for combating turbulence effects on propagating high power laser beams, AS&T proposes, during Phase I, to investigate the process of USLP propagation through the turbulent medium. The critical conditions for this process will be determined and the Adaptive Optics system that will provide controllable delivery of the USLP to a given position through turbulent media will be proposed. The critical component for this solution is the beacon availability and this problem will be solved by basis beaconless and target-in-the-loop approaches.

Benefit:
Propagation of the USLP beam through nonlinear media followed by its self-focusing and filamentation. These effects are further exacerbated by optical inhomogeneity of the host nonlinear medium, such as turbulent atmosphere. Turbulent path introduces spatial variations of the laser beam intensity (scintillations), the effect that manifests itself in the instability of the modulation and uncontrolled beam filamentation at unpredictable distances the aspect that introduces difficulties to a number of practical military and commercial applications of USLP. This Project aims to analyze and simulate performance of the Nonlinear Propagation Beam Control Module specific to optimization and enhancement of ultra-short laser pulse propagation through optically nonlinear and optically non-uniform medium, such as turbulent atmosphere. The performed analysis should demonstrate the ability of the proposed concept and its BECOM implementation to correct turbulent atmosphere induced phase distortions in the propagating laser beam through pre-distortion of its wavefront with beaconless based AO concept.

Keywords:
filamentation, filamentation, self-focusing, Ultra-short laser pulse, Adaptive Optics

Filamentation of ultra-short laser pulse propagation in non-linear media offers significant potentials allowing to address numerous problems in military and commercial sectors. However, practical implementation of this requires an ability to control the USLP at its propagation through inhomogeneous media, like turbulent atmosphere. On the basis of our approach for combating turbulence effects on propagating high power laser beams, AS&T proposes, during Phase I, to investigate the process of USLP propagation through the turbulent medium. The critical conditions for this process will be determined and the Adaptive Optics system that will provide controllable delivery of the USLP to a given position through turbulent media will be proposed. The critical component for this solution is the beacon availability and this problem will be solved by basis beaconless and target-in-the-loop approaches.

Benefit:
In Phase II AS&T will refine the Phase I BECOM design, integrate its breadboard and perform validation of its conceptual design supported with specially developed software specific to the performance operational algorithm. Once proven to operate within the constraints of the linear optics conditions, the lab level BEOCM unit will be augmented to the level required to operate in ONR defined controlled scaled facilities. These sets of tests will allow demonstration of BECOM applicability to support NAVY established operational requirements, such as generation of sub-diffraction focal spots at designated range after propagating through strong turbulence. The performed tests will establish BECOM working envelop and factors that may limit its operation depending upon atmospheric conditions, range and other test parameters.

Keywords:
non-linear self-focusing, ultra short laser pulse, laser beam control