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The recovery profile of an object is of great interest in different technical, metrological and medical applications. In this work we present a system which, through a single graphical interface, we can set grid generation, acquisition and image processing for two different fringe projection methods; such as the Phase-Shifting method and the so-called Takeda method. Both techniques are aimed to obtain surfaces profiles through phase recovery. The use of the proposed system has the advantage that there is no need for decoupled systems for fringe projection for image acquisition and one for processing them. We present some preliminary results obtained using the proposed system.

We started our study with a group of Mexican Males with an Uncorrected Visual Acuity (UCVA) of 20/20, 20/30, and 20/40. The data was obtained using a Nidek OPD Scan ARK 10000 with the Version 1.11b of the working software. With the resulting Zernike coefficients, we calculated the average of the total Wavefront map, the Point Spread Function (PSF), the Optical Transfer Function, (OTF) and the corresponding Modulation Transfer Function (MTF). The purpose of these calculations was to obtain a pattern to be used as a reference to compare with the performance of human eyes after a laser surgery procedure and virgin eyes. In our case, the surgery was performed with an excimer laser Nidek EC-5000 Ver.1.26 W. When the OPD Scan software was upgraded, we realized that the Zernike coefficients for a given eye were different, for each version. Therefore, the aim of this work is to compare our reference pattern of the Zernike coefficients obtained with two different version of the working software.

We discuss the theory, the experiment and applications to the interference resulting of the superposition of two or more Bessel beams propagating in free space and showed for first time a self imaging effect using nondiffracting beams.

We present computer simulations of the 2D Fractional Hilbert Transform, of index P for both amplitude and phase objects. We also present, computer simulations of the isotropic version of the classical Hilbert Transform.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We analyze the possibilities of white light interconnections by controlling the mixture of diffractive colors. In our experiments we used conventional holographic materials to reproduce the spatial frequency codification to obtain the desired color mixture. Experimental verifications are included.

A new family of zone plate is described that have angular phase detours for creating zero axial irradiance. This kind of diffractive optical element may be useful in optical alignment.