The present invention comprises a compact optical see-through head-mounted display capable of combining, a see-through image path with a virtual image path such that the opaqueness of the see-through image path can be modulated and the virtual image occludes parts of the see-through image and vice versa

Apparatus for optical see-through head mounted display with mutual occlusion and opaqueness control capability

The primary routes for creating polymeric channel waveguides are reviewed. Processes, materials, waveguide performance, and applications recently reported in the literature are covered. Emphasis is on an internal diffusion approach under development at Du Pont which has not been widely reported. The intent is to provide a perspective on the flexibility and versatility for fabricating polymer channel waveguides for practical integrated optic applications. >

Low loss channel waveguides in polymers

This is a board to transport and convert optical outgoing free-space signals from a spatial light modulator which comprises: at least one detector to process the outgoing free-space signal; at least one signal transmitter to process the outgoing free-space signal; and at least one outgoing optical signal carrier to carry a converted outgoing signal. Other methods and devices are disclosed.

Optical signal free-space conversion board

A multichip module having high density optical and electrical interconnections between integrated circuit chips includes a substrate overlaying an array of integrated circuit chips. An optical transmitter generates a first optical beam through the substrate and an optical detector receives a second optical beam through the substrate. A hologram is positioned in the path of at least one of the first and second optical beams. An array of electrical contact pads is located on the substrate corresponding to the array of electrical contact pads on the respective integrated circuit chips. A pattern of electrical interconnection lines is located on the substrate for electrically interconnecting the integrated circuit chips. A solder bump between electrical contact pads on the substrate and on the integrated circuit chips establish electrical connections between the substrate and the integrated circuit chips, and also facilitate alignment of the integrated circuit chips with respect to the substrate. The optical transmitter and detector may be mounted on/in the substrate or on/in the integrated circuit chips. The optical transmitter and detector may also be used to provide optical connections external to the microelectronic module, using a holographic substrate to optically link modules. The substrate may also be used to establish optical alignment of the hologram to an underlying optical emitter and/or optical detector without establishing electrical connections thereto.

Microelectronic module having optical and electrical interconnects

Embedded piezoelectric sensors in large civil structures for structural health monitoring applications require data communication capabilities to effectively transmit information regarding the structure's integrity between sensor nodes and to the central processing unit. Conventional communication modalities include electromagnetic waves or acoustical waves. While guided elastic waves can propagate over long distances on solid structures, their multi-modal and dispersive characteristics make it difficult to interpret the channel responses and to transfer useful information along pipes. Time reversal is an adaptive transmission method that can improve the spatiotemporal wave focusing. The present disclosure presents the basic principles of a time reversal based pulse position modulation (TR-PPM) method and demonstrates TR-PPM data communication by simulation. The present disclosure also experimentally demonstrates data communication with TR-PPM on pipes. Simulated and experimental results demonstrate that TR-PPM for data communications can be achieved successfully using guided elastic waves.

System and method for time reversal data communications on pipes using guided elastic waves

This paper presents a study of board-level interconnection requirements for highly parallel and massively parallel computing. Analytical models of the I/O bandwidth of popular interconnection networks have been developed and show that current electronic technologies are poor in supporting the necessary I/O density and bandwidth. Optical interconnects appear to offer greater potential in meeting these I/O requirements. Several possible optical implementations of interconnecting a network of electronic processors are compared. The use of polymer waveguides appears to offer the best solution compatible with existing multiboard system architectures.

Optical interconnections for massively parallel architectures.

Dynamic, untethered array nodes are frequency, phase, and time aligned, and used to focus their transmissions of the same data coherently on a target, using time reversal. Alignment may be achieved separately for the radio frequency (RF) carriers and the data envelopes. Carrier alignment may be by phase conjugation. The data is distributed across the nodes. Data distribution and/or alignment may be performed by a Master node of the array. The nodes capture a sounding signal from the target, in the same time window. Each node converts the captured sounding signal to baseband, for example, using in-phase/quadrature downconversion. Each node stores the baseband samples of the sounding pulse. Each node convolves time-reversed samples of the sounding signal with the data, and upconverts the convolved data to radio frequency. The nodes emit their respective convolved and upconverted data so that the emissions focus coherently at the target.

Distributed co-operating nodes using time reversal

This invention discloses an optical interconnect structure for routing and distributing optical signals on silicon chip carriers to realize high-density packaged optical interconnects for discrete GaAs optoelectronic IC's.

Optical interconnect circuit for GaAs optoelectronics and Si VLSI/VHSIC

Techniques, apparatuses and systems for providing communications based on time reversal of a channel impulse response of a pulse in a transmission channel between a transmitter and a receiver to enhance reception and detection of a pulse at the receiver against various effects that can adversely affect and complicate the reception and detection of the pulse at the receiver.

Techniques and systems for providing data over power in communications based on time reversal

Selected embodiments are directed to methods, apparatus, and articles of manufacture for wireless radio frequency communications. Adjacent antenna array elements of a receiver antenna array are separated by less than the diffraction limit of the radio frequency communication band in which the apparatus and methods operate. A plurality or multiplicity of near-field scatterers are asymmetrically placed in the immediate vicinity of each of the antenna array elements, to perturb the pattern of each of the antenna elements, making the patterns different even below diffraction limit spacing. A transmitter spatially and temporally focuses simultaneous transmissions on each of the antenna array elements, using time reversal communication techniques. The transmitter may transmit through multiple antenna elements, and the channel from the transmitter to the receiver may be subject to multipath phenomena.

Anis Husain

Papers

Optical interconnections for massively parallel architectures.

Distributed co-operating nodes using time reversal

Optical interconnect circuit for GaAs optoelectronics and Si VLSI/VHSIC

Techniques and systems for providing data over power in communications based on time reversal

Apparatus, methods, and articles of manufacture for wireless communications