Research On High-resolution Imaging And Stokes Imaging By Interferenceless Coded Aperture Correlation Holography

Interferenceless coded aperture correlation holography(I-COACH)utilizes incoherent illumination,which is different from the other coherent holography.Utilizing the coded phase mask(CPM),the object light is coded into specific speckle pattern.The object is reconstructed by the speckle pattern and the corresponding point spread function(PSF).Since the patterns of the PSFs varies with the axial distance,I-COACH has the capacity of 3D imaging.I-COACH does not suffer from the speckle noise and the imaging distance is not limited by the coherent length,it suggests that I-COACH has the potential to realize high quality and far-field 3D imaging.For acquiring the PSFs,the mostly adapted method is using a pinhole,which leads to two issues.One is that the cutoff frequency of the reconstruction is limited by the cutoff frequency of the pinhole.The other one is that the imaging distance is limited due to the luminous intensity decreasing with the increase of axial distance.Besides,I-COACH adopt incoherent illumination,and the stokes imaging is compatible to I-COACH.Therefore,this paper also studies the stokes imaging using I-COACH.The main work of this paper is as follows:This paper theoretically demonstrates the parameters correlated to the resolution,by scalar diffraction theory.Different from the imaging systems which adopt lenses,the resolution limit of the I-COACH is correlated to the numerical aperture,scattering degree and the cutoff frequency of the pinhole.This paper demonstrates the resolution limit affected by these parameters though numerical simulation.For circumventing the major problems correlating to the pinhole,this paper proposed to record the PSF by wavefront modulation instead of using a pinhole.The PSF recorded by wavefront modulation is referred to virtual point spread function(VPSF).This paper proofs that the VPSF method has the potential to reach the resolution limit by angular spectrum theory.This paper experimentally demonstrates the high-resolution imaging and the potential of far-field imaging by I-COACH.Automatic recording is also realized by proposed method.This paper studies the stokes imaging by I-COACH.The multi-channel interferenceless coded aperture correlation holography(MCI-COACH)is proposed for stokes imaging.Because the different CPMs are uncorrelated,this paper theoretically demonstrates that multiple reconstructed results can be extracted from one hologram acquired by multiple channels.For cost reduction,this paper proposed utilize one CPM and multiple specific phase mask to realize the MCI-COACH.The numerical simulation and experimental results show that the stokes imaging by MCI-COACH is able to acquire the angle of the polarization accurately.In summary,this paper proposes a method for recording the PSF by wavefront modulation,which is referred to as VPSF and improve the resolution to the resolution limit.This method is capable of reaching the resolution limit in different kinds of PSF-based imaging techniques.This paper also studies the stokes imaging by I-COACH,and realize the incoherent-holography-based stokes imaging.It's helpful to the stereo stokes imaging.