Masaki Fukui

Image logic algebra and its optical implementations

A generic language for optical parallel processing image logic algebra (ILA), is proposed. In ILA a neighborhood configuration pattern (NCP) is introduced, and image transformations are defined by the use of NCP operations. The comprehensive relationship of ILA to symbolic substitution, optical array logic, mathematical morphology, and binary image algebra are clarified. Furthermore, an architecture that is suited for ILA and its optical implementations is proposed.

Experimental verification of parallel processing on a hybrid optical parallel array logic system

A hybrid digital optical computing system is constructed, a variation of the optical parallel array logic system (OPALS). The OPALS is a general-purpose digital optical computing system based on optical array logic, in which image coding and 2-D correlation are used to achieve parallel logical operations. In the constructed system, 2-D correlation for optical array logic is performed optically with a modified multireflective correlator; the other procedures in optical array logic are achieved by electronics including a TV feedback system. We have verified correct execution of programs written by optical array logic on the system. Although the processing speed of the system is still slow because of the sequential process in electronics, it can be drastically improved by replacing the sequential processing devices with parallel ones.

Programming of optical array logic. 2 : Numerical data processing based on pattern logic

A new technique for space-variant processing with optical array logic and a new concept for parallel processing called pattern logic are proposed. Optical array logic is a technique for achieving any parallel neighborhood operation by simple coding, optical correlation, and parallel OR operation. Using pattern logic, various kinds of parallel processing can be realized, which can be implemented by optical array logic. Several kinds of numerical data processing are presented to verify the capability of pattern logic.

Flexible-structured computation based on optical array logic

A flexible processing scheme for various types of structured data is presented. The scheme is based on optical array logic, which is a technique for parallel neighborhood operation using spatial coding and 2-D correlation. In the proposed scheme, virtual processing elements are constructed on an image plane and their functions are emulated with optical array logic. Such a processing system can easily be controlled by programming in optical array logic, so that flexible-structured data processing can be achieved. Several computer simulation results are presented. Referring to the results, requirements for optical implementation are discussed.

High-throughput optical image crossbar switch that uses a point light source array.

A high-throughput optical image crossbar switch (OPIX) that uses a point light source array as the switching device is constructed. A prototype OPIX is used to create various switching patterns for two-dimensional images. The newly constructed OPIX is suitable for high-speed operation because it uses point light sources instead of an optical shutter array as the switching device. Since it is based on an imaging system, the OPIX has a large space-bandwidth product. The introduction of OPIX to optical image data buses of parallel optical processing systems is particularly significant.

Applications of image-logic algebra: wire routing and numerical data processings.

Image logic algebra (ILA) is a comprehensive language for single-instruction stream multidata stream-type parallel processing, particularly for processing that is based on pattern matching. To demonstrate the usefulness of ILA for application to the computer-aided design of very-large-scale-integrated circuits, we describe a mostly parallel wire-routing algorithm based on Lees maze algorithm by using ILA; our computer simulation verifies its validity. Another application to numerical data processing algorithms (including addition and multiplication) that is based on Booths algorithm is also described by using ILA. Furthermore, the computational complexity of the proposed algorithms is evaluated.

Design considerations of the optical image crossbar switch.

Novel types of an optical image crossbar switch based on multiple imaging systems are proposed and demonstrated. The optical systems are based on gometric optics; accordingly, the systems have a large space bandwidth 20 x 20 switching for images with 10(3) x 10(3) pixels is realizable with the proposed optical image crossbar switches. A preliminary experiment is conducted for one of the proposed configurations. The possibility of incorporating the proposed optical switching system into optical parallel processing systems is particularly significant.

Optoelectronic parallel computing system with optical image crossbar switch

A novel architecture based on free-space optics is proposed for optoelectronic parallel computing systems. The main feature of the proposed architecture is its use of the optical image crossbar switch, a free-space optical switch that can directly switch images (two-dimensional optical signals) without any parallel-to-serial conversion. To demonstrate the processing capability of the architecture, I investigate a fully parallel matrix multiplication algorithm for the proposed architecture.

Free-space optical module configuration using a guide-frame assembly method

A new assembly method is described for easy construction of optical modules consisting of guide frames, spacer frames, and a housing frame. This method is used to assemble a two-dimensional optical-fiber collimator and a digital discrete correlator, which are fundamental parts of free-space optical computing systems. We show that a multistage optical system can be constructed simply by stacking of several optical functional blocks. Moreover, these compact modules do not need a conventional optical bench, they are compact, and assembly time is reduced. We demonstrated by experiment that the accuracy of optical modules assembled with this method is within the specifications of the optical system.

Implementations of optical image crossbar switch

Optical image crossbar switch (OPIX), based on a multiple imaging system, is proposed and demonstrated. OPIX is reconfigurable and nonblocking switch for two-dimensional images. As OPIX uses geometrical optics, it has a large space bandwidth. The proposed OPIX is incorporated into a newly proposed optical parallel processing system and initial tests are encouraging.