bluuebunny/crossref_metadata_2025 huggingface dataset:
Array Division by Optical Computing
Authors: Efron U. , Marom E. , Soffer B. H.
Published: February 2023

The theory of feedback, shows that when a feedback system has a loop gain Aβ much larger than unity, the transfer function O/I of the system is almost entirely governed by the elements β contained in the feedback branch.

The output "O" is thus the ratio of "I" to "β". One could translate this operation to an optical two-dimensional division system by replacing I by a "numerator array" and β by a "denominator array".
Optical Implementation of the Perfect Shuffle
Authors: Lohmann A. , Stork W. , Stucke G.
Published: February 2023

The "perfect shuffle" (PS) is a well-known concept for global interconnection networks in parallel computers. It performs a certain permutation of N = 2k elements. Fig. 1 shows two different graphical representations of the PS-operation. In Fig. 1a the actual pathways of the N elements in one PS-step are drawn. If the addresses (positions) of the elements are represented by binary numbers, ranging from 0 to N-1, it is apparent that the PS can be described as a cyclical rotation (to the left) of the address bits (Fig. 1b).
Multi-Level Coded Residue-Based Content-Addressable-Memory Optical Computing
Authors: Mirsalehi M. M. , Gaylord T. K.
Published: February 2023

Digital operations can be implemented by: 1) converting the operation into a sequence of logic steps that can be realized by gates or 2) reading the output directly from a stored truth table. In spite of the superiority of the latter method in speed, it has not been common in the history of data processing. This is partially due to the large sizes of the tables that need to be stored, and partially due to the numerous efficient algorithms that can be programmed on general von Neumann type computers. However, a variety of recent technological advances and a growing need for parallel processing have generated renewed interest in truth-table look-up processing.
Optical Computing and the Hopfield Model
Authors: Psaltis Demetri , Farhat Nabil
Published: February 2023

Hopfield’s model [1] of the neural network describes how a set of very simple, identical computing elements (neurons) can collectively perform complex and powerful operations. The "hardware" with which the model is implemented are thresholding elements (the neurons) and analog weights interconnecting the neurons. Information is stored, according to the model, in the interconnections. Computation is performed by setting the state (on or off) of some of the neurons according to an external input and given this initial stimulus, the system converges to a stable state which we can consider as the result of the computation. Hopfield has shown that when information is stored in the interconnections in the manner he prescribed, the system generally converges to a stored state that is closest to the external input. In other words, the computation that is performed is a nearest neighbor search, a fundamental operation in pattern recognition.
Optical Implementations of the Hopfield Model
Authors: Farhat Nabil , Psaltis Demetri
Published: February 2023

Schemes for implementing the Hopfield model for neural networks optically are described. Numerical and experimental results are presented and the important role for optical bistability is emphasized.
Optical Computer for Pseudorandom Sequence Identification
Authors: Cartwright Steven
Published: February 2023

A Linear Feedback Shift Register (LFSR) is a standard parallel shift register with output taps on some of its stages. If the output taps are combined and fed back to the initial stage, on each clock cycle the shift register will change to a new state. By appropriate selection of the tap connections an n-stage LFSR can be made to cycle through all possible 2n-1 states before repeating the sequence. The output from any stage is called a maximal length pseudorandom sequence. Such a sequence has many of the statistical properties of a sequence of ideal random numbers, but obviously results from a very well defined process. Once a LFSR is known, its associated pseudorandom sequence can be described in full. The inverse problem of identifying the LFSR which generated a given pseudorandom sequence is far more difficult.
Programming an Optical Computer
Authors: Abu-Moustafa Y.
Published: February 2023

Summary not available.
A Digital Design Technique for Optical Computing
Authors: Murdocca M. J. , Streibl N.
Published: February 2023

Optically nonlinear arrays have been studied experimentally in the last few years. Results encourage the development of computer architectures suitable for optics. We present a computer design technique that makes use of optically nonlinear arrays and free-space interconnects. In order to take advantage of the natural parallelism of this architecture without suffering from limitations due to the regularity of the interconnects, novel computing techniques are needed [1]. Pattern transformations and regular interconnects are the basic architectural building blocks of the system presented here. The focus is on computational aspects of the architecture.
Binary Image Algebra and Digital Optical Cellular Image Processors
Authors: Huang K. S. , Jenkins B. K. , Sawchuk A. A.
Published: February 2023

Image processing and image analysis tasks have large data processing requirements and inherent parallelism and are well suited to implementation on digital optical processors because of the parallelism and free interconnection capabilities of optical systems [1][2]. Recently, several techniques for constructing optical cellular logic processors for image processing have been proposed [2]-[5]. Through parallel studies of architectures, algorithms, mathematical structures, and optics we have found that: 1) cellular automata are appropriate models for parallel image processing machines [6]; 2) an image algebra extending from mathematical morphology [7] [8] can lead to a formal parallel language approach to the design of image processing algorithms; 3) the algebraic structure serves as a framework for both algorithms and architectures of parallel image processing; and 4) optical computing techniques are able to efficiently implement image algebra based on cellular logic architectures (e.g. cellular array, cellular hypercube etc.). Here we will first discuss image algebra and then architectures for its implementation.
A Bit Serial Optical Computer
Authors: Jordan Harry F.
Published: February 2023

Optical techniques have a number of potential benefits for information processing. They include a high degree of parallelism, high speeds, short pulses and non-interference of signals. Many of the attempts to use the non-linear optical technology which is beginning to emerge in the device physics area has concentrated on the spatial parallelism available in optics. Problems which have arisen with this approach have included design and fabrication of arrays of optical elements, accuracy of data representation, controlled permutation of data, synchronization with a master clock and optical to electronic interfacing. But spatial parallelism is not the only advantage of optical computing. The extremely high speeds and short pulses which are possible allow the exploitation of the time domain to obtain significant processing power. Serial computer designs are based on the time domain. Exploiting the time domain is not an alternative to spatial parallelism in optical computing but is complementary to it. Since information in an optical computer is represented by pulses propagating at the speed of light there is a homogeneity between time and space which is not present in an electronic computer. Difficult serial design issues must be addressed in optical computer architectures even in predominantly parallel designs. Finally, there are reasons why a serial architecture may lead more rapidly to functional optical computers than one relying heavily on spatial parallelism.
Cellular Optical Processor Architecture with Modulable Holographic Interconnections
Authors: Taboury J. , Wang J.M. , Chavel P. , Devos F.
Published: February 2023

The recent rise in interest in optical computing has already led to considerable conceptual progress in optical processing architectures such as multiple matrix product, associative memories, digital optical computing. Since 3-D optics naturally provides a parallel environment with high connectivity, optical computing becomes an attractive field of reflexion. Nevertheless, in optical cellular logic systems using non linear elements, the practical implementation problems of gate interconnections must be solved.
Residue Position-Coded Look-Up Table Processing
Authors: Goutzoulis A. P. , Davies D. K. , Malarkey E. C. , Bradley J. C. , Beaudet P. R.
Published: February 2023

Residue arithmetic(1) has some very desirable features(2,3) which include: lack of carries, bounded input/output dynamic range and the ability to decompose a calculation into many parallel subcalculations of lesser complexity. Such features, when combined with high-speed position-coded optoelectronic look-up tables (LUT), result in high-speed, power efficient, low complexity processors.
Design of Computer Generated Holograms for E-Beam Fabrication by Means of a Computer Aided Design System
Authors: Farhoosh H. , Lee S. H.
Published: February 2023

Computer generated holograms (CGH) have many potential applications, such as holographic optical elements (HOE), pattern recognition, optical interconnect, and display of abstract objects[1-5]. In order to use these potentials to a full extent, a CGH must be recorded at very high resolution with precision on a large area. High resolution and large area require recording devices that have an extremely large space bandwidth product (SBWP). Electron beam lithography systems can satisfy these requirements. E-beam systems have a SBWP of order of 1010 and they are capable of direct writing patterns of submicron features with very high accuracy.
A Comparison Between Optical and Electrical Interconnections Based on Power and Speed Considerations
Authors: Feldman Michael R. , Esener Sadik C. , Guest Clark C. , Lee Sing H.
Published: February 2023

By replacing electronic transmission lines in very large scale integrated circuits with optical communication systems, increased system performance can be achieved.1,2 Electronic transmission lines suffer from long signal propagation time and large power dissipation as lengths and fanout grow. On the other hand, optical systems are limited by the power dissipation of the injection laser sources and the optical detection speed, fundamentally governed by the supplied optical energy. In this paper, power versus speed tradeoffs are examined for both electrical and optical interconnections. Equations are derived that can be used to determine specific conditions for which optical systems become advantageous. These results are then applied to concurrent wafer scale integrated circuits (WSI) where power, speed, throughput, and cost advantages can be achieved by performing interconnections optically.
Optical MSD Adder Using Polarization Coded Symbolic Substitution
Authors: Ramamoorthy P. A. , Antony S.
Published: February 2023

The optical adder using MSD combines the flexibility and accuracy of digital systems with the parallel information processing capability of optics. Hence the addition of two MSD numbers can be performed in three steps regardless of the number of digits in the MSD numbers. The MSD representation is a subset of the signed-digit representation where radix r equals two. Requirements of fully parallel addition and subtraction and of a unique representation for the zero value are fulfilled by signed-digit representations. A MSD number is represented by three digits
x
i
(i=1¯,0,1). For a precision of b bits, a given decimal number can be represented in MSD number system as follows1,2.
Factored Look-Up Tables for Optical Residue Number System (RNS) Computations**
Authors: Malarkev E.C. , Beaudet P.R. , Bradley J.C. , Davis J.L.
Published: February 2023

The details of factored tables and their uses in RNS multiplication and addition are explained, Optical circuitry necessary for their implementation is given.
Restoring Optical Logic: The Demonstration of Extensible All-Optical Digital Systems
Authors: Smith S.D. , Tooley F.A.P. , Walker A.C. , Craft N. , Wherrett B.S.
Published: February 2023

We have recently shown that by the use of a "lock and clock" architecture and an off-axis configuration of the power and signal beams indefinitely extensible optical logic is possible.
Review of Some Current Optical Computing Research in the Soviet Union
Authors: Rhodes William T.
Published: February 2023

This past July, along with eight other scientists from western countries, I attended a meeting on optical computing held in Novosibirsk. The meeting was sponsored and hosted by the Institute of Automation and Electrometry, USSR Academy of Sciences, Siberian Branch, under the direction of Academician Yu. E. Nesterikhin.
Thermo-Optical Beam Guide and Switching Experiments*
Authors: Peterson Lauren M.
Published: February 2023

Radiation passing through a nonlinear optical medium can lead to a change in the refractive index of that medium. If the radiation is in the form of a focused Gaussian beam, the focal region where the radiation field is the strongest will have the greatest index change and the transverse spatial profile of this index change will be bell-shaped since the transverse radiation profile is Gaussian. For a large f-number focused beam, the focal region is a long cylinder with a transverse graded-index (GRIN) profile quite analogous to a graded index waveguide or fiber. We have used this real-time refractive index waveguide due to one beam of pulsed laser radiation to rapidly redirect or switch a second beam of laser radiation.
Theory of All-Optical GaAs Logic Devices
Authors: Warren M.E. , Koch S.W. , Gibbs H.M.
Published: February 2023

All-optical semiconductor devices are numerically modeled and optimized using a microscopic theory for the optical nonlinearities of room-temperature GaAs. Single-frequency NOR-gate operation in reflection is predicted.
Optical Matrix Encoding for Constraint Satisfaction
Authors: Marsden Gary C. , Kiamilev F. , Esener S. , Lee Sing H.
Published: February 2023

Many Artificial Intelligence problems, such as theorem proving, computer vision, and expert systems, can be seen as constraint satisfaction problems1,2,3. In such problems, constraints are given on any possible solution. Most often, the problem is either explicitly stated in terms of allowed partial solutions or can be converted to such a representation. The objective is to find one or more solutions satisfying all constraints simultaneously, or the determination that no such solution exists. A simplistic approach to solving constraint satisfaction problems is to generate all possible solutions, then test each against the constraints to see if indeed they are satisfied. The process of backtracking provides a marginal improvement by testing increasingly larger partial solutions. Consistent Labelling is a more efficient procedure which eliminates allowed partial solutions that conflict with one another 2. A problem is represented in a constraint network. Arc and path Consistent Labelling eliminate allowed partial solutions that are inconsistent over the smallest closed loops. The remaining allowed partial solutions can then be used in an efficient backtracking search. Using Consistent Labelling on larger loops, it is possible to obtain solutions to constraint satisfaction problems without backtracking4.
High-Speed Optically-Addressed Spatial Light Modulator for Optical Computing
Authors: Rice R. A. , Li W. , Moddel G.
Published: February 2023

Optically-addressed spatial light modulators (OASLMs) provide a technique for processing two-dimensional optical data in parallel optical computing architectures [1,2]. The OASLM presented uses a hydrogenated amorphous silicon (a-Si:H) photosensor and a ferroelectric liquid crystal (FLC) as the modulator.
A Massively Parallel Optical Computer
Authors: Louri Ahmed
Published: February 2023

In this paper, we present a new optical architecture for supporting massively parallel computations. The system processes two-dimensional arrays as basic data objects. The processing is based on the optical symbolic substitution (SS) logic. New SS rules are introduced.
Optical Correlation Computing By Light With Partial Spatial Coherence
Authors: Bykovsky Yu.A. , Markilov A.A. , Smazheliuk M.F. , Starikov S.N.
Published: February 2023

The possihility of optical computing on mutuaI correlation of two-dimensional data arrays by local sign-variable summing in partially spatially coherent light is considered. The experimental results are described.
Modified Brewster Telescopes
Authors: Lohmann Adolf W. , Stork Wilhelm
Published: February 2023

The telescope of Brewster (1781-1868) experiences today a renaissance. It is used for semiconductor lasers in order to change the beam shape from elliptical to nearly circular. It is also used for the temporal compression of laser pulses. In our application the Brewster telescope served to convert a square-shaped beam into a rectangular beam with an aspect ratio of 2:1. Such an anamorphotic process is needed in the context of perfect shuffling, which is an important link in many optical communication networks.
Perspectives in Optical Computing
Authors: Neff John A.
Published: February 2023

Optics is starting to get serious consideration in application areas previously dominated by electronics. One such application area is supercomputing where efforts to increase performance are beginning to turn toward the interconnection of many microprocessors rather than trying to attain a single super processor. The importance of communications in these new multiprocessing architectures has focused attention on optics to provide the necessary bandwidths. This overview of the opportunity for inserting optics into these parallel supercomputer architectures will begin with a brief description of parallel architecture, followed by a discussion of the critical optical device and materials needs.
The Mock Counter
Authors: Yadlowsky Ann B. , Jordan Harry F.
Published: February 2023

The goal of the Bit-Serial Optical Computer project is to build the first all optical stored program digital computer. Because optical pulses may be extremely short and do not interfere, such a machine can potentially operate at very high speeds. The first step on the way to such a machine is a simple optical finite-state machine, the optical counter. This is an optical, bit-serial counter built using the technology to be employed in the Bit-Serial Optical Computer [1]. The Mock Counter [2] is a step on the way to the optical counter.
Optical Transversal Filter With Variable Weights
Authors: Gookin Debra M. , Berry Mark H.
Published: February 2023

We describe an optical transversal filter constructed from off-the-shelf components. The filter is comprised of fiber optics and integrated optical devices. This filter differs significantly from previously constructed filters which all had fixed tap weights,1-3 usually of value unity. An approach used to make fixed weight taps was to produce dielectric mirrors directly in the fiber.3 All of these systems were limited by the inflexibility of their weighting scheme. This limitation adversely affects the filter performance in two ways. First, it is not possible to change the response function of the filter once the filter has been made. Second, it is not possible to correct for tap weight errors. When a fiber optic transversal filter is built, by any technique, there will be some error in the value of the loss and the delay between taps. Fixed weight systems have no technique for self correction.
Applications of a Polarization-Based Optical Processor
Authors: Ittycheriah Abraham P. , Walkup John F. , Krile Thomas F.
Published: February 2023

Optical logic and transforms such as the Walsh and Haar are examples of optical binary arithmetic. A processor capable of evaluating polynomials1 has been used to perform optical logic and Walsh and Haar transforms. This summary describes these applications.
Guided Wave Vector-Matrix Multiplier
Authors: Berry Mark H. , Gookin Debra M.
Published: February 2023

Optical approaches to vector-matrix multiplication have been proposed for 25 years.1 However the development of a versatile, accurate implementation has been lagging. The free space architecture used by Goodman, et al.2 suffered the disadvantage of a fixed photographic matrix mask. Some of these disadvantages were eliminated through the use of acousto-optic2 or electro-optic3 devices. The accuracy of free space systems is critically dependent on the quality of large optics. Alignment, stray light, and temperature fluctuations are difficult to control. The use of fiber optics using a lattice structure approach for vector-matrix multiplication was introduced in 1985.4 These operations were limited to Toeplitz matrices, and mechanical adjustments were necessary to change the matrix elements. Other approaches have included the use of photorefractive media5 and optical implementations of special arithmetics.6
Image Processing Using Polarization-Encoded Optical Shadow Casting II: Edge Detection
Authors: Awwal A. A. S. , Karim M. A.
Published: February 2023

The polarization-encoded optical shadow-casting (POSC) system [1] has shown considerable promise in two dimensional digital image processing applications. Recently, POSC systems were utilized to perform gray level image processing [2], It is very natural for the POSC systems to operate on images which are already in two dimensional form. The generalized POSC algorithm [1] has already been used to accomodate trinary designs [3], programmable logic arrays [4], associative content addressable memories [2], carry-free adder [5], and flip-flops [6].
Polarization-based optical computing using liquid crystals.
Authors: Roux Johannes D. , Leuschner F. Wilhelm
Published: February 2023

Many architectures that perform digital optical logic have been proposed and built. Most of them use intensity-encoded logic where, for example, the presence of light would indicate logical true and the absence of light logical false. This way of encoding logic information has several disadvantages, e.g. light being irretrievably lost when switching from light ON to light OFF.
Optical Network Design for a BIT-serial Parallel Processor
Authors: Lohmann Adolf W. , Stucke Gregor
Published: February 2023

When designing a future optical parallel processor one might try to get inspiration from an existing architecture with the following features: Software can be copied from the existing electronic system; the processing elements are simple; the control has SIMD character; the connection network is fairly primitive.
Symbolic Substitution Based Parallel Adder/Subtracter
Authors: Barua S.
Published: February 2023

Fully parallel processors can be designed by employing a technology that is inherently parallel, a suitable number system, and an efficient encoding scheme for handling the data. Binary number system is accepted as the best suited in electronic computers. The delay due to carry propagation in binary arithmetic makes the binary number representation a very weak candidate for an optical processor that is inherently parallel. The modified signed-digit (MSD) number system1 satisfies the requirements of fully parallel addition and subtraction by limiting the carry propagation to one position to the left. The design of an optical MSD adder capable of performing addition/subtraction in three stages has already been proposed.2 The above design is based on polarization-coded symbolic substitution. A reduction in the number of stages can be achieved by exploiting some of the unique characteristics of MSD. The optical implementation of the MSD adder with reduced number of stages is discussed in this paper. The MSD digits are coded as three different polarization states of light. Polarization-coded symbolic substitution is used to implement the adder.
Dynamic Optical Processing for Parallel Digital Addition and Subtraction
Authors: Kurokawa Takashi , Fukushima Seiji , Suzuki Hideo
Published: February 2023

An optical arithmetic processor for digital addition will be one of the most important basic elements in optical computers. Several optical implementations of half or full adder circuits have been proposed 1-4 However, dynamic processing has not been developed for parallel digital addition. The main problem is real-time parallel operation of the half adder and the dynamic construction by cascadable configuration.
Flexible-Structured Computation Base on Optical Array Logic
Authors: Tanida Jun , Fukui Masaki , Ichioka Yoshiki
Published: February 2023

Optical computing techniques have excellent features for large capacity information processing, such as massively parallelism, high speed processing, crosstalk free interconnection capability, and so on. Among those features, reconfigurability of optical processing systems should be stressed. To utilize this excellent feature, we have considered flexible-structured computation with optical array logic (OAL).1,2 The programmability of OAL is fully utilized for designing such a flexible-structured computing system.
Switching in an Optical Interconnect Environment
Authors: Goodman Joseph W.
Published: February 2023

Optical interconnects are gaining importance in a wide range of applications, ranging from interconnection of supercomputers and workstations to interconnection of multiple chips on a single board. With the development of any interconnect technology, eventually the need for switching arises. Thus the switching of optical interconnects is a topic of much current interest.
Digital Optoelectronic Processor Array Architectures for Vector-Matrix Multiplication: Erratum
Authors: Feldman Michael R. , Guest Clark C.
Published: February 2023

We have noted an error in our original paper.1 Equation (5) should read as
Hybrid opto-electronic co-processor implementation inside a computer workstation
Authors: Lebreton Guy , Frantz Rémy
Published: February 2023

The experimental realization of an optical processor is described. The goal is to implement in a computer workstation a linear algebra processor based on analog relaxation, to help the host computer solving three types of problems:

- solution to systems of linear equations (e.g. partial differential equations),

- matrix inversion,

- computation of eigenvalues and eigenvectors.
Sequential Logic Operation Using Optical Parallel Processor Based upon Polarization Encoding
Authors: Hashimoto Masashi , Kitayama Ken-ichi , Mukohzaka Naohisa
Published: February 2023

Optical parallel processing based upon various polarization encodings(1) is a promissing concept for the practical implementation. The optical processor performing programmable and cascade operations on real-time basis, has been constructed.(2)
Multiplexed Hybrid Interconnection Architectures
Authors: Ozaktas Haldun M. , Goodman Joseph W.
Published: February 2023

A major advantage of optical and superconducting interconnections is their ability to transfer large amounts of information per unit cross section over long distances. Let the maximum information flux a given communication medium can support be denoted by I and be measured in bits/m
2
sec. For the length scales involved in a computing system (< 10 m), it is possible to reduce the effects of dispersion and attenuation to the extent that I may be assumed to be independent of length for optical and superconducting interconnections. On the other hand, 1 is a decreasing function of communication length for resistive interconnections, making them disadvantageous over longer distances. However, for distances less than about the order of a centimeter, they can provide greater information flux than optical or superconducting interconnections.
Progress in diffractive phase gratings used for spot array generation
Authors: Morrison Rick. L. , Walker Sonya L.
Published: February 2023

Prototype free-space photonic switching[1] and optical computing systems[2] rely on spot array generating systems to produce illumination needed to transfer information between arrays of optical processing elements. In these systems, the light from a single laser is split into a set of beams that are focussed onto an array of optical logic devices, such as S-SEEDs[3]. Although several methods are available for generating spot arrays[4], diffraction gratings (also referred to as Dammann gratings[5] [6]) were chosen to generate the spot arrays. Their advantages can be traced to the ease with which they are incorporated into an optical system. As illustrated in figure 1, the grating is simply inserted into the collimated beam with the appropriate imaging optics. Their operation is relatively insensitive to alignment. Provided the collimated beam illuminates a suitable size area of the grating, the performance is determined by the design and fabrication process.
Design rules for fanout elements recorded as volume holograms
Authors: Herzig H. P. , Prongué D. , Ehbets P. , Dändliker R.
Published: February 2023

Optical fanout elements split a single laser beam into a regular array of equally intense light spots in one- or two-dimensions. They are used in many applications of modern optics, such as parallel optical processing and fiber optic communication. This paper deals with the recording of efficient fanout elements as volume holograms. We have applied coupled wave theory to determine how efficiency and uniformity of the fanout depend on the recording conditions.
Photorefractive Parallel Matrix-Matrix Multiplier Using a Mutually Incoherent Laser Array
Authors: Hong John , Yeh Pochi
Published: February 2023

Wave mixing and holographic recording in photorefractive media have been used to perform parallel matrix-vector multiplication [1]. Although the technique can be extended to perform parallel matrix-matrix multiplication, the implementation requires critical alignment of the matrix elements. In this paper, we propose to demonstrate a novel technique to perform parallel matrix-matrix multiplication which uses the simultaneous formation of multiple gratings in a photorefractive crystal. The concept is shown in Fig. 1 where a simple example is used. The matrices to be multiplied are given by amn and bkl. While all the light sources shown in the figure are of the same nominal wavelength, each source differs from its neighboring source by some frequency δw which is chosen to satisfy δω ≫ 1/τ where τ is the photorefractive response time.
A Design of an Optical Parallel Multiprocessor Based on Optical Array Logic Modular Architecture
Authors: Tanida Jun , Nishimura Yasunori , Ichioka Yoshiki
Published: February 2023

Optical array logic (OAL) is proposed as a basis of parallel optical digital computing.1 This technique is applied to an optical digital computing system called OPALS (optical parallel array logic system).2 Processing of the OPALS is based on SIMD (single instruction multiple data) and iterative structures, which is designed to utilize the characteristics of OAL effectively. However, there are problems related to the structure of the OPALS. Since the OPALS has a closed architecture, it is difficult to extend the system. Although many data can be processed simultaneously, minute operations for a part of data cause processing inefficiency. In addition, necessity of three dynamic components in the OPALS results in complication of hardware and degradation of processing throughput. Thus a new concept for system construction is an important subject in OAL scheme.
A Hardware Compiler for Digital Optical Computing
Authors: Murdocca Miles , Gupta Vipul , Majidi Masoud
Published: February 2023

A hardware compiler for translating descriptions of digital circuits from a hardware description language (HDL) into gate-level layouts is under development at Rutgers University. The layouts are customized for optical processors that make use of arrays of optical logic gates interconnected in free-space with regular interconnection patterns such as perfect shuffles, crossovers, or global interconnects. Specific processors that the hardware compiler supports include the S-SEED based all-optical processor developed at AT&T Bell Labs, the S-SEED based all-optical processor under development at the Photonics Center at RADC/Griffiss AFB, and the acousto-optic modulator based RISC processor under development at OptiComp Corporation.
Shared Memory Optical/Electronic Computer: Architecture Design
Authors: Waterson Clare , Jenkins B. Keith
Published: February 2023

Several abstract models of parallel computation have been developed and studied by the computer science and parallel processing communities [1, 2]. The shared memory models are among the most computationally powerful of these models. They benefit from substantial theoretical foundations, and many algorithms have been mapped onto these models in order to characterize theoretically optimum parallel performance. A number of attempts have been made to develop electronic parallel architectures based on the shared memory model. Most of them have been unsuccessful, primarily due to the complexity of the interconnection network hardware and its associated control.
A Guided-Wave Acoustooptic Matrix Algebra Processor Module*
Authors: Kar-Roy A. , Tsai C. S.
Published: February 2023

Various architectures for implementing matrix algebra processors (MAPs) have been proposed and developed in bulk-wave optical systems(1−7) as well as in integrated optic (IO) devices(8−10) Bulk-wave optical systems have the advantage of an added dimension in implementing 3-D architectures over planar IO devices in which only 2-D architectures are possible. But the IO devices have the potential advantages in terms of drive power requirement, size, robustness, stability and planar technology for mass production. In this paper, we report on a guided-wave acoustooptic (AO) analog MAP module that is capable of implementing high-speed matrix-vector and matrix-matrix multiplications. The architecture, the working principle, and a preliminary MAP constructed on a 1.0 X 10.0 X 28.0 mm3 Y-cut LiNbO3 substrate to demonstrate the multiplication of a 4 X 4 matrix with a 4-element vector, are presented.
Ultrafast All-Optical Fiber Soliton Logic Gates
Authors: Islam M.N. , Chen C.J. , Soccolich C.E.
Published: February 2023

We demonstrate a 5.8pJ switching energy all-optical NOR-gate with a fanout of six that is based on timing shifts from soliton dragging [1] in a fiber. This three-terminal, cascadable gate satifies all requirements for a clocked digital optical processor. Furthermore, we show that soliton dragging logic gates are one embodiment in fiber form of a novel switch architecture of time domain chirp switches (TDCS). Although TDCS have a long latency, for high bit-rate applications TDCS lead to switching energies approaching one Picojoule.
Bandwidth as a Virtual Resource In Reconfigurable Optical Interconnections
Authors: Chiarulli Donald M. , Levitan Steven P. , Melhem Rami G. , Qiao Chunming
Published: February 2023

This work is focused on reconfigurable optoelectronic interconnection networks: networks constructed of optical waveguides in which messages are switched or routed by means of optoelectronic devices [Goo89].
Digital Optical Computing
Authors: Brenner K. H.
Published: February 2023

Summary not available at time of printing.
Optical Implementations of The Modified Signed-Digit Algorithm
Authors: Zhou Shaomin , Campbell Scott , Yeh Pochi , Liu Hua-Kuang
Published: February 2023

Modified Signed-Digit (MSD) computing is an effective parallel processing method which is very suitable for optical implementation.
Time of Flight Packet Synchronizers
Authors: Love Carl E. , Jordan Harry F.
Published: February 2023

The data rates of modern communication networks are reaching speeds at which traditional flip-flops are not effective. The problem is that the bit time is on the same order of magnitude as the feedback time of the flip-flop.
Optically Interconnected Multichip Modules using Computer Generated Holograms
Authors: Feldman Michael R. , Morris James E. , Childers John , Nakkar Mouna , Kiamilev Fouad
Published: February 2023

Current electrical multichip modules will limit the performance of many next-generation highly parallel computational systems.
An Optically Connected Parallel Machine
Authors: Monro D. M. , Dallas J. A. , Nicholls J. A. , Cripps M. D. , Crossland W. A.
Published: February 2023

Supercomputers are entering a phase in which the quest for faster communications in multiprocessor systems will be a dominant issue[1].
Cellular processing with diffractive optical elements
Authors: Kirk Andrew , Tabata Tomohira , Ishikawa Masatoshi
Published: February 2023

As the number of nodes within a parallel processing system is increased it becomes more difficult to achieve a global interconnection between them.
Concept and Implementation of the fractional Fourier Transform
Authors: Lohmann Adolf W.
Published: February 2023

We assign the degree P=1 to the ordinary Fourier transform.
Iterative Design of Computer Generated Fresnel Holograms for Free-Space Optical Interconnections
Authors: Kress Bernard C. , Lee Sing H.
Published: February 2023

We present an iterative algorithm to design computer generated holograms (CGHs) for optical interconnections.
Spectral Hole-Burning, Holographic Storage and Processing
Authors: Wild Urs P. , Bernet Stefan , Altner Stefan , Maniloff Eric S. , Renn Alois
Published: February 2023

The lowest electronic transitions of many absorbing centers in solid hosts consist of extremely narrow zero phonon lines distributed over a broad spectral range.
Wavelength Multiplexed Computer Generated Volume Holography
Authors: Rosen Joseph , Segev Mordechai , Yariv Amnon
Published: February 2023

We demonstrate the first experiment of multiple-storage of computer generated holograms (CGHs) in a volume holographic storage medium.
Photorefractive Phased-Array-Radar Processor Dynamics
Authors: Weverka Robert T. , Sarto Anthony W. , Wagner Kelvin
Published: February 2023

Large adaptive, two dimensional phased-array radar antennas can consist of thousands of antenna elements, have GHz bandwidths, and must be able to steer and adapt the antenna beam rapidly in a dynamic signal environment.
Performance Evaluation of an Acousto-Optic Wide Band Correlator System
Authors: Griffin R.D. , Lee J.N.
Published: February 2023

We have designed and built an acousto-optic (AO) correlator system that is used as a matched filter processor integrated into a digital signal processing system, and have analyzed parametrically the efficiency of correlating a continuous time series waveform.
Optoelectronic fuzzy logic inference system using beam scanning laser diodes
Authors: Itoh Hideo , Watanabe Masanobu , Mukai Seiji , Yajima Hiroyoshi
Published: February 2023

Recently fuzzy control techniques have been widely used in the control systems which are difficult to implement using conventional control methods.
Reversal input superposing technique for all-optical neural networks
Authors: Hayasaki Yoshio , Tohyama Ichiro , Yatagai Toyohiko , Mori Masahiko , Ishihara Satoshi
Published: February 2023

Basic operations of a simple neural network model are a spatial weighted sum operation, including arithmetic operations of multiplication and addition, and a nonlinear operation.
An Optical Algorithm for a Plane Image Reconstruction from its Boundary
Authors: Karasik Y. B.
Published: February 2023

As is known optical analog processors can readily extract boundary ∂A from any plane image A by means of both optical differentiation of the image [10] and optical symbolic substitution (SS) [5] [3].
Holographic storage of 750 images in a photorefractive crystal memory
Authors: Selviah D. R. , Tao S. , Midwinter J. E.
Published: February 2023

Photorefractive crystals have been studied for many years [1-3] since they offer the possibility of dense holographic storage of high resolution images in a compact volume.
Surface Relief Grating Array on GaAs Waveguides for Optical Spot Array Generation
Authors: Twyford Elizabeth J. , Tayag Tristan J. , Jokerst Nan Marie , Kohl Paul A.
Published: February 2023

Optical spot array generators are useful for inputs to optical processing and computing systems. In this paper we demonstrate rib waveguides overlaid with many micrometer-scale grating areas which produces an array of optical beams. This beam array generator can produce a regular matrix of spots which processors such as S-SEED arrays require, as well as spot patterns in less regular shapes, such as L-shape, which are useful for other types of processors [1]. The grating outcoupler approach offers an advantage over the binary phase grating approach to spot array generation because arbitrary patterns can be implemented with the flexible arrangement of the grating areas. In addition, this technique is relatively insensitive to variations in input wavelength (e.g. mode-hopping in a semiconductor laser) and to temperature variations of the device. Finally, the highly directional nature of grating outcoupling yields beams with very low divergence, easing alignment tolerances.
Material Limitations in Volume Holographic Copying
Authors: Campbell Scott , Zhang Yuheng , Yeh Pochi
Published: February 2023

Optical memory systems utilizing volume holographic storage (VHS) have received considerable attention in recent years[1-3]. One aspect of VHS is the ability to copy stored data from an archive (a VHS medium containing N permanently-stored data sets) to a secondary storage medium (SSM). To achieve the copying of volume holographic memories from the archive to the SSM, three primary approaches can be utilized: parallel[4], incremental[5], and sequential[6]. In the parallel approach, there exist N mutually incoherent read beams that enter the archive and read out and copy all N stored data sets simultaneously. In the incremental approach, there exists a single coherent read beam that is rapidly multiplexed over time (in angle, wavelength, phase, et cetera) in a manner such that it reads out and copies all N data sets serially, over many repeated iterations in which each iteration time is short compared to the SSM’s response time. In the sequential approach, there also exists a single coherent read beam that is multiplexed over time (in angle, wavelength, phase, et cetera) but such that it reads out and copies the N data sets sequentially in a manner that follows an appropriate (single-pass) exposure schedule. In this paper, we explore the fundamental material limitations in each of these copying approaches for the cases of all-optical, quasi all-optical, and hybrid opto-electronic copying schemes. These limitations include the maximum allowable intensity, IA, into the archive that will not damage it, the resulting total intensity, ID, of the diffracted beam from the archive as a function of N, IA, and other archival material and geometry constraints, dark conductivity, shot and Kerr noise in the SSM, cross-talk, and the characteristics of any devices that may be placed between the archive and the SSM.
Optical bus systems using a cylindrical lens
Authors: Mori Masahiko
Published: February 2023

In recent years, many kinds of optical board-to-board interconnection systems had been proposed and some of them were demonstrated[1-9]. Basic interconnection systems using laser diodes and photo detectors connected through free space[6] or Selfoc lenses[5] were shown. In these systems basic concept is based on sets of one-to-one interconnections with free space. Another approach is using fibers. To achieve fixed many-to-many interconnections, optical fiber ribbon, laser diode arrays and detector arrays are usefull[3].
A Constant-Time Parallel Sorting Algorithm and its Optical Implementation Using Smart Pixels
Authors: Louri Ahmed , Hatch James A , Na Jongwhoa
Published: February 2023

Sorting is a basic, fundamental operation used for many symbolic, numeric, and artificial intelligence (AI) tasks [1]. Because of its importance, there has been a great deal of work on developing and analyzing sorting algorithms and architectures [2]. In this paper, we present a novel constant-time parallel sorting algorithm and an efficient optical implementation capable of both determining the positions of the sorted data elements and physically reordering them in O(1) time steps. It uses photonics for highly parallel interconnects and optoelectronics, in the form of “smart pixels” for processing. Thus, it exploits the advantages of both the optical and electrical domains.
Weighted Space-Variant Local Interconnections Based on Micro-Optic Components: Crosstalk Analysis and Reduction
Authors: Huang Chingchu , Jenkins B. Keith , Kuznia Charles B.
Published: February 2023

(1) Introduction. The use of diffractive optical elements (DOE’s) and microlens arrays in optical interconnection systems can potentially provide high throughputs and small system volumes, using components that are amenable to automated design and mass production techniques. This paper considers fixed-weight neural network interconnections based on such components, and focuses on the realm of small system volumes and short propagation lengths (~1 mm) with potential for cascading into a compact, multilayer free-space system. We consider the space-variant interconnection system of Fig. 1, and achieve short propagation lengths by restricting each fanout pattern to a local neighborhood. The system uses an array of NxN sub-DOE's at the input plane to connect to an array of NxN detectors at the output plane. For this locally connected neural network interconnection, each sub-DOE stores one weighted fanout pattern that connects to MxM nearest neighbors in the output plane. The beam incident on each sub-DOE comes from a modulator or an emitter (not shown), which represents an interconnection input node (e.g., an output of a neuron unit). The optics of the interconnection system provides a Fourier transform (in magnitude) from each sub-DOE to the detector array, which serves as a set of neuron unit inputs. We constrain the sub-DOE spacing to be equal to the detector spacing to allow for use in multilayer systems. A globally connected space-variant system can be realized similarly by replacing the microlens array with a bulk lens and letting each input node connect to all output plane detectors [1,2]. The minimum propagation distance and system volume can be shown to be approximately proportional to M and N^M for the local system, and N and A3 for the global system, respectively. While the local system can be used in a smaller volume, its crosstalk levels can be high due to reconstruction noise (e.g., diffraction orders outside of the local fanout neighborhood) of each sub-DOE. In this paper, we describe a crosstalk reduction method enabled by varying the mapping from reconstructed spot locations to detector locations. Several novel DOE designs for, and simulations of, local fixed-weight neural network interconnections are evaluated as a test of this method.