An imaging method and associated system for producing high-resolution images. The method includes illuminating an object or scene with coherent radiation such as beams from a laser and then, collecting scattered light with a plurality of subapertures rather than a single large aperture. The method continues with coherently detecting, such as with heterodyne detection, the scattered light to measure the complex amplitude incident on each subaperture and digitally reconstructing images from the coherently detected light for the subapertures. Then digital co-phasing is performed on the subapertures using an image sharpness or quality metric to form an image having the resolution of the total subaperture area. The method may also include determining an aimpoint in the formed image, calculating a phase screen, directing laser beams through the subapertures towards the aimpoint, and co-phasing the laser beams by applying the phase screen to form a single beam.

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 system includes a reference projector that projects collimated beams of light into the optical system entrance aperture which are imaged by an image recording device. The beams produce fiducial images present in every image captured by the imaging recording device. The fiducial images can be used to characterize the performance of the optical system and derive distortion correction coefficients. The distortion correction coefficients can be applied to a portion of an image, such as a group of pixels, or to the entire image, to thereby compensate for distortions in the optical system. In some embodiments, e.g., airborne cameras, the projector is rigidly coupled to an inertial measurement unit. The ability of the airborne camera to perform object geolocation from imagery is improved. The fiducial images enable optical system performance to be characterized and distortion correction coefficients to be obtained and thereby improve the accuracy of a ray angle calculation to the object of interest. Furthermore, the ray angle can be related to an inertial measurement system coordinate system using a direction cosine matrix.

An apparatus measures optical deviations caused by an aircraft canopy. In this apparatus, a light source generates a beam of light. A collimator, optically coupled to the light source, then collimates the beam of light. An optical assembly patterns the collimated beam of light into a patterned array of subaperture beams, which is directed onto an imaging screen. The patterned collimated beam of light produces images, which are electronically imaged and recorded to memory. An undistorted image results when the aircraft canopy is not placed in a path of the patterned collimated beam of light. However, a distorted image results when the aircraft canopy is placed in a path of the patterned collimated beam of light and distorts the patterned collimated beam of light. A processing unit compares the distorted image to the undistorted image to determine the optical distortions caused by the aircraft canopy.