Computer-Generated Holograms of Three-Dimensional Objects Synthesized from Their Multiple Angular Viewpoints

this paper is concerned mainly with a new method of computing the complex function s(u, v) from the object function t(x s , y s , z s ) rather than in a coding method of the final CG

Invited Paper Noninvasive optical tomographic imaging by speckle ensemble

We survey recently invented methods of optical tomographic imaging through scattering medium. The threedimensional structure of an object hidden between two biological tissues is recovered from many noisy speckle pictures obtained on the output of a multi-channeled optical imaging system

CThC5 2005 Conference on Lasers & Electro-Optics (CLEO) Towards Reconstruction ofEmbedded Objects with Multiple Spackle Images for Medical Diagnostics

Abstract: Anew methodofseeing objects hidden in scatteringmedium from multiple speckle images is demonstrated. The entire noisy images from lens array are digitally processed to obtain the desired image ofthe hidden objects. 1

NOISE 2 imaging system: seeing through scattering tissue with a reference point

We propose a f ly-eye-like imaging system for seeing objects embedded in scattering media. Objects are recovered from many speckled images observed by a digital camera through a microlens array. Each microlens in the array generates a speckle image of the object buried between two layers of chicken breast tissue. In the computer each image is Fourier transformed jointly with an image of the speckled pointlike source captured under the same conditions. A set of the squared magnitudes of the Fourier-transformed pictures is accumulated to form a single average picture. This final picture is again Fourier transformed, resulting in the reconstruction of the hidden object. © 2004 Optical Society of America OCIS codes: 030.6140, 030.6600, 170.1650, 170.3010, 170.3880. During the past decade, optical imaging through scattering media has proved to be an effective medical diagnostic because it is safe, noninvasive, and lower in cost than conventional radiation techniques. Many optical techniques for imaging through diffusing tissues have been proposed, 1 despite the strong attenuation and scattering of light caused by tissue constituents

Stereoscopic imaging through scattering media

We develop and experimentally test a method for three-dimensional imaging of hidden objects in a scattering medium. In our scheme, objects hidden between two biological tissues at different depths from the viewing system are recovered, and their three-dimensional locations are computed. Analogous to a fly’s two eyes, two microlens arrays are used to observe the hidden objects from different perspectives. At the output of each lens array we construct the objects from several sets of many speckled images with a previously suggested technique that uses a reference point. The differences of the reconstructed images in both arrays with respect to the reference point yield the information regarding the relative depth among the various objects

Fourier, Fresnel and Image CGHs of three-dimensional objects observed from many different projections

We describe new techniques of synthesizing three types of computer-generated hologram (CGH); Fourier, Fresnel and image CGHs. These holograms, aimed to reconstruct three-dimensional (3-D) objects, are synthesized by means of a unique algorithm of fusing multiple perspective views of the observed scene. The hologram is initially generated in the computer as a Fourier hologram. Then, it can be converted to either Fresnel or image holograms by computing the desired wave propagation and the interference process. By illuminating the ready-to-use CGHs with a collimated plane wave, a 3-D image of the objects is reconstructed. Diffraction efficiency enhancement of the above algorithm by superimposing a random phase on the object during the CGH formation is also presented. Computer simulation and experimental results of the constructed 3-D objects demonstrate the suggested technique

114 Digital correlation hologram implemented on optical correlator

A new kind of computer-generated hologram termed digital correlation hologram (DCH) has been developed and demonstrated with promising results. This hologram is composed of two separate sub-holograms. The reconstructed image is obtained as a result of a spatial correlation between the hologram's two parts. The DCH codes two complex functions which are generated by an iterative optimization procedure. The correlation between the two sub-holograms is implemented by means of a joint transform correlator (JTC). When the double-elements hologram is displayed on the JTC input plane, and illuminated by a plane wave, a desired image is constructed on part of the correlator output plane. The DCH can be used for security and encryption systems, as the desired image will be received in the output plane only when the two specific sub-holograms are placed at the input plane of the JTC. Simulation and experimental results demonstrate the suggested technique

Computer-generated holograms of three-dimensional realistic objects recorded without wave interference

We propose a method of synthesizing computer-generated holograms of real-life three-dimensional (3-D) objects. An ordinary digital camera illuminated by incoherent white light records several projections of the 3-D object from different points of view. The recorded data are numerically processed to yield a two-dimensional complex function, which is then encoded as a computer-generated hologram. When this hologram is illuminated by a plane wave, a 3-D real image of the object is reconstructed. Keywords: 3-D image processing, 3-D holography, Computer-generated hologram 1