Systems and methods for minimizing aberrating effects in imaging systems
View Patent ↗An imaging system for reducing aberrations from an intervening medium, and an associated method of use are provided. The system may be an optical or task-based optical imaging system including optics, such as a phase mask, for imaging a wavefront of the system to an intermediate image and modifying phase of the wavefront such that an optical transfer function of the system is substantially invariant to focus-related aberrations from the medium. A detector detects the intermediate image, which is further processed by a decoder, removing phase effects from the optics and forming a final image substantially clear of the aberrations. Other systems may employ an encoder that codes wavefronts of acoustical waves propagating through a medium to make the wavefronts substantially invariant to acoustical aberrations from the medium. Imaging and decoding of the wavefronts reverse effects of the wavefront coding and produce sounds substantially free of the aberrations.
1. A biometric optical recognition system, comprising:
optics, including a phase-modifying element, for encoding a wavefront of electromagnetic energy from an object and for imaging the electromagnetic energy to an intermediate image;
a detector for detecting the intermediate image, wherein a modulation transfer function detected at the detector contains no zeros within a passband of the detector; and
means for task based image processing output data from the detector to determine image information about the object and without generating an image for human viewing.
2. The system of claim 1 , wherein the means for task based image processing comprises a decoder, connected with the detector.
3. The system of claim 2 , the decoder comprising an all-pass filter in the frequency domain.