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Browsing by Subject "Diffraction"

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Coherent imaging of periodic thick fine isolated structures

Sheridan, John T. ; Sheppard, Colin (Optical Society of America, 1993-04-01)

The diffraction orders and coherent bright and dark field images produced by isolated steps and grooves (notches and trenches) are examined. The isolated structures are approximated by means of a grating with a large ...
Comparison of Laplacian differential reconstruction of inline holograms recorded at two different wavelengths and distances

Ryle, James P. ; Li, Dayan ; Sheridan, John T. (Optical Society of America, 2010-04-11)

We record two holograms using two different illuminating wavelengths. Subtracting these holograms, the resulting reconstruction is an approximation to the second order Laplacian differentiation of the object wave.
Diffraction by volume gratings : approximate solution in terms of boundary diffraction coefficients

Sheridan, John T. ; Solymar, L. (Laszlo) (Optical Society of America, 1992-09-01)

An approximate analytic method is presented that permits the calculation of all the output waves, both backward and forward traveling, for slanted, transmission-type volume gratings replayed at the Bragg angle and perfectly ...
Dual wavelength digital holographic Laplacian reconstruction

Ryle, James P. ; Li, Dayan ; Sheridan, John T. (Optical Society of America, 2010-09-15)

Access to the spatial derivatives of an optical wave field can be used to enhance edge detection, focusing, and holographic imaging. It was recently shown that, by using digital holographic techniques, the Laplacian of an ...
Fundamental diffraction limitations in a paraxial 4-f imaging system with coherent and incoherent illumination

Kelly, Damien P. ; Sheridan, John T. ; Rhodes, William T. (Optical Society of America, 2007-07-01)

In the usual model of an imaging system, only the effects of the aperture stop are considered in determining diffraction-limited system performance. In fact, diffraction at other stops—those associated with different lens ...
Generalization of the boundary diffraction method for volume gratings

Sheridan, John T. (Optical Society of America, 1994-02-01)

The boundary diffraction method (BDM) is an approximate method that permits the derivation of analytic solutions for the output beams, both forward and backward propagating, that arise from the fundamental nature of ...
Optical wave propagation simulation, Wigner phase-space diagrams, and wave energy confinement

Rhodes, William T. ; Sheridan, John T. ; Hennelly, Bryan M. (Optical Society of America, 2005-10-16)

The number of samples required for efficient numerical simulation of wave propagation can be determined by a combination of Wigner phase-space techniques, wave energy confinement arguments, and a theorem relating energy ...
Speckle orientation in paraxial optical systems

Li, Dayan ; Kelly, Damien P. ; Kirner, Raoul ; Sheridan, John T. (Optical Society of America, 2012-02)

The statistical properties of speckles in paraxial optical systems depend on the system parameters. In particular, the speckle orientation and the lateral dependence (x and y) of the longitudinal speckle size can vary ...
Three-dimensional static speckle fields. Part II. Experimental investigation

Li, Dayan ; Kelly, Damien P. ; Sheridan, John T. (Optical Society of America, 2011-09-01)

In Part I [J. Opt. Soc. Am. A 28, 1896 (2011) of this paper, the physical model for fully developed speckle is examined based on two critical assumptions. (i) It is assumed that in the object plane, the speckle field is ...
Three-dimensional static speckle fields. Part I. Theory and numerical investigation

Li, Dayan ; Kelly, Damien P. ; Sheridan, John T. (Optical Society of America, 2011-09-01)

When monochromatic light is scattered from an optically rough surface a complicated three-dimensional (3D) field is generated. These fields are often described by reference to the 3D volume (extent) of their speckles, ...