University of Southern California

B Keith Jenkins

Armand R Tanguay, Jr

Novel apparatus for simultaneous spatial modulation of a set of angularly multiplexed individually coherent but mutually incoherent optical beams is disclosed, comprising means for generating a set of two or more individually coherent beams that have at least one optical wavelength in common, pairwise, and are assured to be mutually incoherent, and means for directing the set of individually coherent but mutually incoherent beams to a spatial modulation means, such that a spatially overlapping group of individually coherent but mutually incoherent beams overlap spatially in at least one region of the spatial modulation means and are angularly multiplexed within the region. Such simultaneous spatial modulation is a key feature, for example, in highly multiplexed photonic interconnection, memory, and display systems with maximum optical throughput efficiency and minimum crosstalk, based on parallel incoherent/coherent double angularly multiplexed holographic recording and readout principles. Simultaneous spatial modulation is also of importance for the provision for arbitrarily weighted and independent interconnections in the development of densely interconnected photonic implementations of neural networks, photonic interconnection networks for telecommunications switching and digital computing applications, optical information processors, optical memories, and optical displays. Variants of the apparatus are provided that allow for the incorporation of optically isolated semiconductor laser diode arrays, vertical cavity surface emitting laser arrays that are partially mutually incoherent and partially wavelength division multiplexed, the combination of laser diode and phase modulator arrays to provide for controllable mutual incoherence, both pixelated and non-pixelated spatial light modulators, and both planar and volume holographic or diffractive optical elements employed as spatial light modulation means.

Apparatus for simultaneous spatial modulation of incoherent/coherent angulary multiplexed optical beams

Apparatus is provided for the readout, and in certain applications the display, of information stored within incoherent/coherent double angularly multiplexed volume holographic optical elements. Such multiplexed volume holographic optical elements are based on parallel incoherent/coherent double angularly multiplexed volume holographic recording and readout principles, and are designed to exhibit maximum optical throughput efficiency and minimum crosstalk. Applications for this novel holographic readout apparatus, when used in conjunction with the aforementioned incoherent/coherent double angularly multiplexed volume holographic optical elements, include photonic interconnections for neural networks, telecommunications switching, and digital computing; optical information processors and optical memories; and optical display systems. The holographic readout apparatus is based primarily on the use of a spatially distributed source array, which contains a plurality of optical sources that are at once both individually coherent and mutually incoherent. The incorporation of the incoherent/coherent source array enables embodiments of the apparatus that in turn allow for incoherent superposition of reconstructed images and simplified parallel readout of the multiplexed volume holographic optical elements. The additional provision of spatial light modulation means allows for independent selection of the subset of stored holographically-encoded information patterns to be simultaneously read out or displayed. The holographic readout apparatus is capable of reading out and displaying information stored in several variants of incoherent/coherent double angularly multiplexed volume holographic optical elements, including those that are either optically recorded or computer generated, and that are based on either continuous-volume (bulk) or stratified-volume holographic media.

Apparatus for incoherent/coherent readout and display of information

Novel multiplexed volume holographic optical elements for the development of highly multiplexed photonic interconnection and holographic memory systems with maximum optical throughput efficiency and minimum crosstalk, based on parallel incoherent/coherent double angularly multiplexed volume holographic recording and readout principles, are disclosed. These principles further provide for arbitrarily weighted and independent interconnections, which are of potential importance in the development of densely interconnected photonic implementations of neural networks, photonic interconnection networks for telecommunications switching and digital computing applications, optical information processors, and optical memories. Utilization of the principles that are key features of this holographic element allows for the single step transfer of all or part of the information stored in a three-dimensional holographic storage device to a second such device in a single exposure step. Variants of the multiplexed volume holographic optical element include bulk holographic recording media as well as stratified volume holographic optical elements, comprising in either case both holographic (optical) modulation patterns and computer-generated holograms. Further variants of the multiplexed volume holographic optical element incorporate a subhologram structure within the volume holographic optical element that allows for high efficiency recording in certain real time photorefractive media.

Incoherent/coherent double angularly multiplexed volume holographic

Computation-intensive applications such as sensor signal processing, sensor fusion, image processing, feature identification, pattern recognition, and early vision place stringent requirements on the computational capacity, size, weight, and power dissipation of modular computational systems intended for both embedded and high performance computer environments. Such ultra high speed, ultra high density computational modules will typically be configured with multiple processor, memory, dedicated sensor, and digital signal processing chips in close-packed multichip modules. The present invention relates to a novel architecture and associated apparatus for the development of highly multiplexed photonic interconnections between pairs of such electronic chips incorporated in vertical stacks within three-dimensional multichip module configurations. Vertical signal transmission through the chip substrates is accomplished by using a planar-waveguide-based optical power bus to provide a parallel array of beams to read out a modulator array that is flip-chip bonded to each silicon substrate. Local and quasi-local connectivity in the vertical dimension is accomplished by using diffractive optical structures that provide for both point-to-point interconnections and weighted fan-out within a local neighborhood. Global connectivity is incorporated by means of computer-generated volume holographic optical elements that are fabricated as a multilayer diffractive optical element. Several different architectural implementations of such computational modules are provided to address applications that include high-bandwidth two-dimensional displays, multilayer neural networks, image processors, multiple processors with access to shared memory, and rending engines for computer animation and graphics. In addition, subsystems of the computational-module architecture and apparatus are described that provide for compact optical readout of modulator-based flat panel displays.

Modulator-based photonic chip-to-chip interconnections for dense

Novel apparatuses for readout of multiplexed volume holographic optical elements, based on parallel incoherent/coherent double angularly multiplexed holographic recording and readout principles, provide for hologram readout with high optical throughput efficiency and minimal crosstalk. Such holographic element readout apparatuses have applications in photonic interconnections for neural networks, telecommunications switching and digital computing; optical information processors and optical memories; and optical display systems. Embodiments are included that allow incoherent superposition of reconstructed images and simplified parallel readout of the volume holographic optical elements. The apparatuses can read out holographic elements that are either optically or computer generated and that are based on continuous-volume or stratified-volume holographic media.

Incoherent/coherent readout of double angularly multiplexed volume

The present invention relates to a novel source array comprising a plurality of sources of optical illumination that are at once both individually coherent and mutually incoherent. A primary application of such a source array is to provide the requisite optical source beams in a novel architecture and associated apparatus for the development of highly multiplexed photonic interconnection networks and holographic optical elements with maximum optical throughput efficiency and minimum interchannel crosstalk, based on parallel incoherent/coherent holographic recording and readout principles that are described herein. In one embodiment, the source array is configured from a plurality of coherent sources of illumination; in a second embodiment, a single source of coherent illumination is expanded to illuminate a phase modulator array, within which each separate phase modulator is driven at a distinct oscillation frequency such that the set of resultant modulated beams exhibits mutual incoherence. Such incoherent/coherent source arrays are critical for providing arbitrarily weighted and independent interconnections, which in turn are of potential importance in the development of neuro-optical computers, as well as photonic interconnection networks and multiplexed holographic optical elements. In addition, the extremely difficult problem of copying the contents of a three-dimensional holographic storage device in one step is enabled by utilization of the incoherent/coherent source arrays that are the key features of the present invention.

Incoherent/coherent source array for multiplexed holographic recording

The present invention relates to a novel spatial light modulator comprising a plurality of individual pixels that each contain separate detectors, electronic circuitry, and optical modulators. A primary application of such a spatial light modulator is to provide the requisite nonlinear relationship between a plurality of optical beams fanned in to each detector on the one hand, and a plurality of optical beams fanned out from such modulator on the other, on a pixel-by-pixel basis. In one embodiment, the spatial light modulator is configured to differentially amplify the inputs to two separate detectors within each pixel, and to transform i

Spatial light modulators for incoherent/coherent multiplexed holographic

The present invention relates to a novel architecture and associated apparatus for the development of highly multiplexed photonic interconnection networks and holographic optical elements with maximum optical throughput efficiency and minimum interchannel crosstalk, based on parallel incoherent/coherent holographic recording and readout principles. This scheme further provides for arbitrarily weighted and independent interconnections, which are of potential importance in the development of neuro-optical computers, as well as photonic interconnection networks and multiplexed holographic optical elements. In addition, the extremely difficult problem of copying the contents of a three-dimensional holographic storage device in one step is soluble by utilization of the architectural principles and specified apparatus that are key features of this invention.

Growing community of inventors

Long Beach, CA, United States of America

B Keith Jenkins