A detailed analysis of the quaternion generic Jacobi-Fourier moments (QGJFMs) for color image description is presented. In order to reach numerical stability, a recursive approach is used during the computation of the generic Jacobi radial polynomials. Moreover, a search criterion is performed to establish the best values for the parameters α and β of the radial Jacobi polynomial families. Additionally, a polar pixel approach is taken into account to increase the numerical accuracy in the calculation of the QGJFMs. To prove the mathematical theory, some color images from optical microscopy and human retina are used. Experiments and results about color image reconstruction are presented.
This document presents an Optical Model to visualize 3-D data arrays, taken from Computer Tomography (CT). The Optical Model simulates a planar wave front of light that goes through the materials of different refractive index. With this method we assign pseudo-color to any of the materials (skin, bone, or soft tissue) that are in the volume.
We propose a low-cost optical system that is able to simply generate computer-generated holograms and rainbow type and true-color Lippmann type holograms. In this system, a microimaging system is applied to reduce the digitized optical data/patterns to achieve about 0.45 µm of optical resolution for rainbow hologram recording and an about 60-deg viewing angle for the Lippmann hologram. The system is designed as a turn-key machine switching between different operating modes. Custom-generated software is applied to calculate and write digital fringe patterns at real-time speed. Applications for the digital rainbow hologram include computer-generated holograms, anticounterfeiting security labels, 3-D display, and 2-D/3-D truecolor holographic stereogram images for the Lippmann hologram. This single-process synthesizing system can be considered as a fully functioning hologram printer.
In this work, we consider the use of circular moments for invariant classification of images which have been
blurred by motion. The test images of the objects under consideration have been acquired when they are
vibrating. For this task an experimental setup is implemented to generate vibrations. A comparative analysis
using several circular moment sets is presented; the studied sets are Zernike, Pseudo-Jacobi-Fourier,
Orthogonal Mellin-Fourier, shifted Chebyshev-Fourier, and radial harmonic Fourier. The classification
method is tested using images of mechanical parts which have intrinsically little differences between them, as
screws with millimetric or standard threads. Experimental results and the optical setup used are presented.
An optical system, which can generate digital holograms of Rainbow type and Lippmann type, is proposed. In this
system, a micro-imaging system is applied for reducing the digital image patterns to achieve about 0.45 micron optical
resolution for rainbow hologram recording, and resulting about 90 degree viewing angle for the Lippmann hologram.
The system is designed for both of Lippmann and Rainbow hologram recording mode through simply turning keyswitches.
A fully functioning software is applied to calculate digital fringe patterns and control the entire equipment.
Both types of holograms, Rainbow and Lippmann types, are recoded from calculated optical images so that it could be
much easier to combine 2D or/and 3D or more multiplex optical data into one hologram through a simple working plan
of art design to achieve a high resolution true color hologram. Applications for the digital Rainbow hologram include
CGH, anti-counterfeiting security label, 3D display, etc, and 2D/3D true color holographic stereogram image for the
Lippmann type recording mode. With this single process synthesizing system, it is considered as a fully functioning
hologram printer. Examples of both of true color rainbow and Lippmann holograms are presented.
A new digital hologram data generation and recording method of computer generated holograms (CGH) is described in
this paper. The application of using this automatic system can be for display, security and diffractive optical device. As
an experimental example, an algorithm of a mathematic model of one-step setup was proposed for creating a white light
reconstruction holographic stereogram. The experimental hologram size is 1cm x1cm using 16 perspective CG images,
with 3200 pixel x 3200 pixel per each image. A new calculating algorithm was introduced for processing large quantity
of data. In addition, a new high speed and high speed digital optical data recording method was applied in the recording
process. The method achieves about 0.4 micron spot size resolution. A digital hologram of 1 inch x 1 inch size has
been written in 5 hours by this method, where an incoherent single beam is used as the only recording light source.
Experimental results show that the digital image processing as well as the recording method is successful and can be
applied for display, security holograms, Kinoform and Diffractive Optical Element applications.
In this paper we introduce the affine spatial overlap operation defined as a generalization of the two-dimensional convolution and cross-correlation operations. Our attention is focused on the rotational overlap operation and some of its mathematical properties as well as its application to shape description. Based on the auto-rotational overlap operation, a one-dimensional signature is proposed as a shape representation for planar binary objects with bounded support. We provide illustrative examples of its digital computation using different binary objects. In addition, physical realization of the 2-D rotational overlap operation is demonstrated with a hybrid optical-digital system for real time processing. The experimental setup uses a microcomputer controlled high-precision rotatory stage for performing analog rotations at the input plane of an incoherent two lens correlator architecture.
In this work we present an optical-digital system that uses a liquid crystal display (LCD)for the approximate reconstruction of binary images by using the Zernike moments. We use the fact that, each Zernike polynomial can be mapped as an intensity distribution and therefore can be readily displayed with a LCD in an optical incoherent system. On the other hand, the reconstruction of the input image can be obtained from a discrete sum of the data matrices
corresponding to the Zernike images weighted by suitable coefficients. These can be numerically computed by using their orthogonality property. The Zernike images acquired by the optical-digital system generate a basis set for the image reconstruction, which depends on both LCD and CCD sensor spatial resolution. The reconstruction is implemented with only thirty six real-valued Zernike moments.
We describe the analytical calculation for the Fourier transform of the semicircle aperture function. The calculation is presented in polar co-ordinates. The Fourier transform is composed of the sum of the typical Bessel's function of one order plus a complex infinite power-series of radial terms with angular coefficients which are obtained from a recurrence formulae. A digital image of the Fourier transform via the FFT of the binary semicircle aperture is presented.
We present a study of the intensity variations of the joint Fourier spectrum when one of two input objects is rotated while the other remains fixed by determining the average contrast as a function of the angle of rotation. The visibility behavior is explained in a theoretical and experimental way for simple test objects whose fine analog rotations are acquired with an optomechanical system that uses a high precision rotatory stage.
The Fiber Optic Interferometric Sensors, FOIS, advent has opened the door to the field application of the interferometry. FOIS allow the disconession between a critical measurement stage (the interferometer) and the measurands site. Moreover, all the information about the measurands are coded in terms of optical phase modulation. Applications and recent advances of the Fiber Optic Interferometric Sensors technology will be reviewed. Laser-based FOIS and White-Light-based FOIS are the two main classes in which the FOIS are developed. Applications range from point sensors of physical parameters (vibration, acceleration, displacement, temperature, etc.) to chemical measurement (traces of ions in water) to sensing network for the development of smart structures FOIS participated to the foundation of the guided-wave single- mode technology and they are even today an important battle-field for experimenting advanced components and architectures.