Improvement of spectral and axial resolutions in modified coded aperture correlation holography (COACH) imaging system

A. Vijayakumar, Joseph Rosen

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

Abstract

Coded aperture correlation holography (COACH) is a recently developed incoherent digital holographic technique. In COACH, two holograms are recorded: The object hologram for the object under study and another hologram for a point object called PSF hologram. The holograms are recorded by interfering two beams, both diffracted from the same object point, but only one of them passes through a random-like coded phase mask (CPM). The same CPM is used for recording the object as well as the PSF holograms. The image is reconstructed by correlating the object hologram with a processed version of the PSF hologram. The COACH holographic technique exhibits the same transverse and axial resolution of the regular imaging, but with the unique capability of storing 3D information. The basic COACH configuration consists of a single spatial light modulator (SLM) used for displaying the CPM. In this study, the basic COACH configuration has been advanced by employing two spatial light modulators (SLMs) in the setup. The refractive lens used in the basic COACH setup for collecting and collimating the light diffracted by the object is replaced by an SLM on which an equivalent diffractive lens is displayed. Unlike a refractive lens, the diffractive lens displayed on the first SLM focuses light with different wavelengths to different axial planes, which are separated by distances larger than the axial correlation lengths of the CPM for any visible wavelength. This characteristic extends the boundaries of COACH from three-dimensional to four-dimensional imaging with the wavelength as its fourth dimension.

Original languageAmerican English
Title of host publicationHolography
Subtitle of host publicationAdvances and Modern Trends V
EditorsJohn T. Sheridan, Miroslav Hrabovsky, Antonio Fimia
PublisherSPIE
ISBN (Electronic)9781510609679
DOIs
StatePublished - 1 Jan 2017
EventHolography: Advances and Modern Trends V 2017 - Prague, Czech Republic
Duration: 24 Apr 201727 Apr 2017

Publication series

NameProceedings of SPIE - The International Society for Optical Engineering
Volume10233

Conference

ConferenceHolography: Advances and Modern Trends V 2017
Country/TerritoryCzech Republic
CityPrague
Period24/04/1727/04/17

Keywords

  • Coded phase mask
  • Computer holography
  • Digital holography
  • Incoherent imaging systems
  • Phase shift
  • Spatial light modulators
  • Spectrometer

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering

Fingerprint

Dive into the research topics of 'Improvement of spectral and axial resolutions in modified coded aperture correlation holography (COACH) imaging system'. Together they form a unique fingerprint.

Cite this