Analysis of in-line Fresnel holograms via chirp separation

Ozgen M. T.

OPTICAL ENGINEERING, cilt.45, sa.3, 2006 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 45 Sayı: 3
  • Basım Tarihi: 2006
  • Doi Numarası: 10.1117/1.2182147
  • Dergi Adı: OPTICAL ENGINEERING
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Anahtar Kelimeler: in-line Fresnel holograms, digital holography, numerical reconstruction, chirp separation, time (space)-frequency representations, time (space)-varying filtering, 2-DIMENSIONAL WAVELET TRANSFORM, COHENS BILINEAR CLASS, DIGITAL HOLOGRAPHY, RECONSTRUCTION, REPRESENTATIONS
  • Anadolu Üniversitesi Adresli: Evet

Özet

A two-step computational technique for object reconstruction from digitized in-line Fresnel holograms of particle fields is proposed that eliminates the preliminary stage of depth extraction, when the goal is recovery of only the object cross-sectional shape. The first step involves a space/spatial-frequency domain chirp separation algorithm based on a two-dimensional (2-D) separable space-varying filtering scheme to separate a hologram into its single-object components. As the second step, a recently proposed Fourier synthesis technique is applied to separated components to reveal the cross-sectional morphology of individual 2-D objects, if they are sufficiently small as compared to the hologram size. The proposed method and a modified version of it based on 1-D filtering for performance improvement are illustrated on synthesized holograms. These simulations indicate that closely spaced planar objects can be recovered without significant dispersion, and back-to-back objects can also be reconstructed with tolerable leakage if they are sufficiently apart. (c) 2006 Society of Photo-Optical Instrumentation Engineers.