An improved, adaptive optics control system is disclosed. The system comprises a wavefront corrector, a wavefront sensor, a wavefront reconstructor and a wavefront controller. The wavefront corrector has a surface controlled by a plurality of actuators. The wavefront slope sensor has a subaperture separation mechanism for defining a plurality of subapertures through which the distorted wavefront can pass, each subaperture corresponding to an actuator of the wavefront corrector. The wavefront slope sensor produces a wavefront sensor output signal for each subaperture indicative of the distortion of the wavefront. The wavefront reconstructor is adapted to receive the wavefront sensor output signals and calculate corresponding phase estimates based thereon, each phase estimate having a signal-to-noise ratio. The wavefront reconstructor generates a plurality of correction signals to be applied to each of the actuators of the wavefront corrector, each correction signal having a bandwidth. The wavefront controller is adapted to selectively adjust the bandwidth of each correction signal based at least in part on at least one of the signal-to-noise ratio of the corresponding phase estimate of the actuator to which it is to be applied, the fraction of each subaperture that is illuminated by the distorted optical wavefront, and the signal level of the at least one pixel within each subaperture. A method of optical wavefront distortion correction is also disclosed.

An optical field sensing system and an associated method are provided that are tolerant of scintillation. The system includes a wavefront sensor that measures gradients across a wavefront at a first resolution defined by the subapertures of the wavefront sensor. The system also includes an intensity sensor that measures the intensity across the wavefront at a higher resolution. The system further includes a wavefront processor that determines respective phases across the wavefront. In addition to the gradients and the intensity measurements, the wavefront processor may determine the respective phases based also upon the noise affiliated with the measurements. In this regard, the wavefront processor may determine the respective phases across the wavefront at least partially based upon the gradients as adjusted by weights that are based upon the intensity measured by the intensity sensor and are influenced by evidence of scintillation.

An incoming laser beam is relayed to a steering mirror and a phase correction device. The beam is relayed from the phase correction device to a focal plane array and to a wavefront sensor (WFS). Low order steering mirror tilt corrections can be based on data from the focal plane array. The WFS outputs data on multiple channels to a field programmable gate array (FPGA), with each of the WFS channels corresponding to a subaperture of the beam wavefront. The FPGA calculates phase corrections for each of the subapertures and forwards those corrections to the phase correction device. The FPGA also calculates tilts for the steering mirror based on the WFS output data, which tilts can be used instead of tilts based on focal plane array data. The phase corrections may be based on modulo 2.pi. phase error calculations and/or modal phase error calculations.

A closed loop compensation system including a deformable mirror including an array of spaced actuators. An array of spaced sensors is mapped in optical space to reside between pairs of actuators. A lens system receives a wavefront from the deformable mirror and focuses sub-apertures of the wavefront onto individual ones of the spaced sensors. A sequencer addresses each actuator and associated sensor in the arrays. A compute unit is configured to respond to the sequencer to set a first actuator to an adjusted stroke position and then adjust the stroke of subsequent actuators to locate, to a pre-established position, the focused sub-aperture on a sensor in the pathway between each particular subsequent actuator and a neighboring previously adjusted portion of the mirror to compensate for sub-aperture tilt while maintaining relative phase between sub-apertures.

A free space optical communication system includes an adaptive optical power regulator. The adaptive optical power regulator adapts to changes in effective loss associated with the free space optical path. In one embodiment the adaptive optical power regulator adapts to scintillation losses. In another embodiment, the adaptive optical power regulator further adapts to changes in atmospheric loss associated with changes in weather.