Open AccessResolution enhancement in nonlinear interferenceless COACH with point response of subdiffraction limit patterns
Author(s) -
Mani Maran Ratnam,
Vijayakumar Anand,
Yusuke Ogura,
Joseph Rosen
Publication year - 2019
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.27.000391
Subject(s) - optics , holography , digital holography , point spread function , aperture (computer memory) , numerical aperture , point (geometry) , image resolution , physics , spatial frequency , computer science , phase (matter) , resolution (logic) , artificial intelligence , mathematics , acoustics , wavelength , geometry , quantum mechanics
Interferenceless coded aperture correlation holography (I-COACH) is a non-scanning, motionless, incoherent digital holography technique for 3D imaging. The lateral and axial resolutions of I-COACH are equivalent to those of conventional direct imaging with the same numerical aperture. The main component of I-COACH is a coded phase mask (CPM) used as the system aperture. In this study, the CPM has been engineered using a modified Gerchberg-Saxton algorithm to generate a random distribution of subdiffraction spot arrays on the digital camera as a system response to a point source illumination. A library of point object holograms is created to calibrate the system for imaging different lateral sections of a 3D object. An object is placed within the calibrated 3D space and an object hologram is recorded with the same CPM. The various planes of the object are reconstructed by a non-linear cross-correlation between the object hologram and the point object hologram library. A lateral resolution enhancement of about 25% was noted in the case of I-COACH compared to direct imaging.