Phasefocused

Phasefocused is a term used in imaging and signal processing to describe methods and systems that prioritize the phase component of a signal in order to enhance focusing, reconstruction, or sensing. Rather than relying primarily on amplitude information, phasefocused approaches seek to extract or exploit phase information to determine spatial or temporal structure.

In optics, phasefocused techniques can improve image resolution and depth discrimination by deducing wavefront phase from measurements, enabling better autofocus, aberration correction, and 3D imaging. In acoustics, ultrasound and sonar can use phasefocused processing to refine localization and improve contrast. In radar and MRI, phasefocused information is leveraged to reconstruct scenes or images from phase-differenced data.

Common strategies include phase retrieval, phase unwrapping, and holographic or interferometric methods that encode phase into measurable quantities. Phasefocused retrieval attempts to recover the phase of a complex signal from intensity data, often using iterative algorithms. Holography and interferometry directly measure phase shifts relative to a reference.

Phasefocused processing can also involve synthetic aperture techniques and wavefront sensing to improve resolution beyond conventional limits. Advantages of phasefocused methods include improved axial and lateral resolution, better coherence, and more robust depth estimation under certain conditions. Limitations include sensitivity to noise, phase ambiguities, and higher computational requirements. Real-world performance depends on sensor quality, calibration, and the stability of the measurement environment.

See also: phase retrieval, holography, interferometry, wavefront sensing, synthetic aperture radar.