Imaging through random media continues to be a challenging problem of crucial importance in a wide range of fields of science and technology,ranging from telescopic imaging through atmospheric turbulence in astronomy ...Imaging through random media continues to be a challenging problem of crucial importance in a wide range of fields of science and technology,ranging from telescopic imaging through atmospheric turbulence in astronomy to microscopic imaging through scattering tissues in biology.To meet the scope of this anniversary issue in holography,this review places a special focus on holographic techniques and their unique functionality,which play a pivotal role in imaging through random media.This review comprises two parts.The first part is intended to be a mini tutorial in which we first identify the true nature of the problems encountered in imaging through random media.We then explain through a methodological analysis how unique functions of holography can be exploited to provide practical solutions to problems.The second part introduces specific examples of experimental implementations for different principles of holographic techniques,along with their performance results,which were taken from some of our recent work.展开更多
Scattering media,such as diffused glass and biological tissue,are usually treated as obstacles in imaging.To cope with the random phase introduced by a turbid medium,most existing imaging techniques recourse to either...Scattering media,such as diffused glass and biological tissue,are usually treated as obstacles in imaging.To cope with the random phase introduced by a turbid medium,most existing imaging techniques recourse to either phase compensation by optical means or phase recovery using iterative algorithms,and their applications are often limited to two-dimensional imaging.In contrast,we utilize the scattering medium as an unconventional imaging lens and exploit its lens-like properties for lensless threedimensional(3D)imaging with diffraction-limited resolution.Our spatially incoherent lensless imaging technique is simple and capable of variable focusing with adjustable depths of focus that enables depth sensing of 3D objects that are concealed by the diffusing medium.Wide-field imaging with diffraction-limited resolution is verified experimentally by a single-shot recording of the 1951 USAF resolution test chart,and 3D imaging and depth sensing are demonstrated by shifting focus over axially separated objects.展开更多
基金support from a Grant-in-Aid for Transformative Research Areas(A)Grant Number A20H05888.
文摘Imaging through random media continues to be a challenging problem of crucial importance in a wide range of fields of science and technology,ranging from telescopic imaging through atmospheric turbulence in astronomy to microscopic imaging through scattering tissues in biology.To meet the scope of this anniversary issue in holography,this review places a special focus on holographic techniques and their unique functionality,which play a pivotal role in imaging through random media.This review comprises two parts.The first part is intended to be a mini tutorial in which we first identify the true nature of the problems encountered in imaging through random media.We then explain through a methodological analysis how unique functions of holography can be exploited to provide practical solutions to problems.The second part introduces specific examples of experimental implementations for different principles of holographic techniques,along with their performance results,which were taken from some of our recent work.
文摘Scattering media,such as diffused glass and biological tissue,are usually treated as obstacles in imaging.To cope with the random phase introduced by a turbid medium,most existing imaging techniques recourse to either phase compensation by optical means or phase recovery using iterative algorithms,and their applications are often limited to two-dimensional imaging.In contrast,we utilize the scattering medium as an unconventional imaging lens and exploit its lens-like properties for lensless threedimensional(3D)imaging with diffraction-limited resolution.Our spatially incoherent lensless imaging technique is simple and capable of variable focusing with adjustable depths of focus that enables depth sensing of 3D objects that are concealed by the diffusing medium.Wide-field imaging with diffraction-limited resolution is verified experimentally by a single-shot recording of the 1951 USAF resolution test chart,and 3D imaging and depth sensing are demonstrated by shifting focus over axially separated objects.
