Axsun Technologies, Inc.

The Charles Stark Draper Laboratory, Inc.

Infraredx, Inc.

Jeffrey A Korn

Dale C Flanders

Peter S Whitney

Steven J Byrnes

Walid A Atia

Juha-Pekka J Laine

Michael G Moebius

Gregg E Favalora

Ian Ward Frank

Eric T Hoke

Benjamin F Lane

Stephen P Smith

Michael Francis Miller

Jonathan Robert Coppeta

Gregory P Blasche

Robin Mark Adrian Dawson

Matthew T Jamula

Minh Van Le

Paul A Bohn

Anthony Kopa

Randal A Murdza

Joseph M Kinast

Xiaomei Wang

Simone B Bortolami

Daniel M Meiser

Eric E Fitch

Robert L Payer

Yu Nathan Li

Dennis M Callahan, Jr

Timothy J McCarthy

Walter R Buchwald

Steven C Fawcett

Baturalp R Arslan

L James Newman, Iii

Raymond V Pourmand

A bijective coded aperture system uses mirror system with a multitude of reflector elements attached to an absorbing, such as black, substrate. Each of the reflector elements is independently placed at a different angle with respect to each other in such a manner that the image of the scene is replicated several times at the focal plane and on the image sensor. Moreover, these replicated images may be overlapping. An image processor can then execute reconstruction methods of the image to faithfully represent the scene.

Reflective bijective method and device for coded aperture image acquisition and reconstruction

A system and method for metrology and profilometry using a light field generator are disclosed. For this purpose, a system such as an optical analysis system scans a sample using light, and detects light reflected off a sample in various ways. The system operates different operational modes including a backscatter intensity, a triangulation, and an interferometric mode. For this purpose, the optical analysis system includes one or more optical angle modulation systems, such as surface acoustic wave (SAW) modulators, that emit light, a sample holder, and a scanning system that scans the one or more SAW modulators relative to the sample holder. The system performs tomographic reconstructions of information generated by the scans to create 3D maps/volume datasets of the sample.

Metrology and profilometry using light field generator

A system and method for improving spatial light modulator (SLM) devices such as Surface Acoustic Wave (SAW) modulators are disclosed. The SAW modulators can improved angular bandwidth and suppress unwanted diffractive orders. In one example, a coating layer(s) is applied to a proximal face of the SAW modulator to improve coupling of guided modes into leaky modes. Additionally, applying coating layers(s) such as a hybrid anti-reflective/highly reflective coating to an exit face of the SAW modulator can suppress transmission of undesired diffractive order(s).

SAW modulators with phase and angle selective optical coatings

A communication system for a hypersonic vehicle uses a distributed antenna system, an impedance matching circuit that provides impedance matching between a transmitter and/or receiver and the selected one or more antennas of the distributed antennas system and a surrounding plasma sheath, near-field probes to determine impedance of the plasma sheath adjacent to each of the probes and thus predict behavior of the respective antennas near the probes, and a control system that selectively connects a transmitter and/or receiver to one or more of the antennas based upon the antennas that are seeing the most favorable transmission or reception characteristics and controlling the impedance matching is to provide impedance matching for the selected antennas.

Distributed antenna with closed-loop impedance matching for high speed vehicles

A light steeling system and method for diffractive steering of electromagnetic radiation such as visible light is disclosed. Embodiments of the light steering system include leaky-mode SAW modulators as light modulator devices. The SAW modulators preferably include reflective diffractive gratings. The gratings are mounted to/patterned upon an exit face that opposes an exit surface of the SAW modulator, in one example. Steering of light signals emitted from the SAW modulators in these systems can be accomplished by varying wavelength of light signals introduced to the SAW modulators, and/or by varying frequency of RF drive signals applied to the SAW modulators. In addition, light field generators that incorporate SAW modulators of the proposed light steering system within displays of the light field generators are also disclosed.

System and method for diffractive steering of electromagnetic radiation

A visual navigation system includes a compass configured to orient a user in a heading direction, an image sensor configured to capture a series of successive navigation images in the heading direction, one or more of the navigation images having at least two reference markers, data storage memory configured to store the series of successive navigation images, a navigation processor configured to identify at least one principal marker and at least one ancillary marker from the at least two reference markers, the principal marker positioned within a principal angle and the ancillary marker positioned within an ancillary angle, which is greater than the principal angle, and to determine heading direction information based on a position of the at least one principal marker and/or the at least one ancillary marker in the successive navigation images, and a user interface configured to provide the heading direction information to the user.

Camera-based heading-hold navigation

A laser system for a spectroscopic catheter system uses multiple semiconductor gain media having gain peaks at different wavelengths. The output from the gain media is preferably coupled into single-mode fiber using conventional opto-electronic packaging techniques. As a result, the laser oscillator source has a spectral output that is wider than the gain bandwidth of a single medium to enable it to access the entire spectrum of interest, which is presently in the near infrared. Moreover, the semiconductor gain media can be packaged in a stable and controlled environment for long-term performance.

Spectroscopic catheter system with widely tunable source and method of operation

A detector system for a fiber optic component is insensitive to stray light. Specifically, the invention comprises a detector chip, which converts received light into an electric signal. A baffle substrate is positioned over the detector chip. This baffle substrate has a transmission port through which an optical signal is transmitted to the detector chip. As a result, light that is not directed to be transmitted through the port is blocked by the baffle substrate. In this way, it rejects stray light that may be present in the hermetic package. A detector substrate is provided on which the detector chip is mounted. This detector substrate preferably comprises electrical traces to which the detector chip is electrically connected. The detector substrate can further comprise bond pads for wire bonding to make electrical connections to the electrical traces.

Stray light insensitive detector system and amplifier

A monitoring system has the capability to monitor multiple signal bands simultaneously. Specifically, in one embodiment, the monitoring system can simultaneously monitor the C- and L-bands. As a result, the time to scan through the spectral band can be reduced by half. The system comprises a signal source for an optical signal having spectrally separated channels distributed within a first spectral band and a second spectral band. A tunable filter filters this optical signal. A dichroic filter separates the first spectral band from the second spectral band in the optical signal, which has been filtered by the tunable filter. Thereafter, first and second optical detectors detect the respective spectral bands to the filtered optical signal.

Optical channel monitoring system with simultaneous C-band and L-band detection

A system and process for tuning the PER of an electronic system during and/or after its manufacture includes fixtures that allow for the axial rotation of the polarization-maintaining optical fiber relative to the optical system after the optical fiber has been installed in the system. The degradation in the PER ratio of the optical system results from mechanical stresses placed on the fiber during the manufacture of the systems. For example, in the case of optical pump manufacturing, the semiconductor laser is installed on a submount. The PM fiber enters a package through a fiber feedthrough in a ferrule and then is secured down onto the submount, such that the endface of the pigtail is held in proximity to the exit facet of the semiconductor laser. In such systems, highly robust fixturing processes are used, typically such as solder bonding, in which the fiber is metallized and solder bonded either directly or indirectly to the submount. Further, solder is typically applied to seal the ferrule around the fiber since these packages must be hermetically sealed to provide for the long-term stable operation. The solder bonding processes can create asymmetries in the residual stress fields applied around the circumference of the fiber after the solder has cooled. These asymmetric stress fields lead to distortions in the stress-induced birefringent medium of the fiber. This results in coupling between the two polarization modes of the PM fiber, and consequently the degradation of the PER of the system from that expected from the separate components, for which the present invention can compensate.

System and process for post alignment polarization extinction ratio compensation in semiconductor laser system

A system for assessing the quality of the optical connection between a catheter and a console is described that avoids the necessity of a calibration port, although one can still be provided if desired. It operates by monitoring the level of light returning from the catheter head and specifically the degree to which this returning light is attenuated. Reflections will arise at the catheter head's optical window due to the discontinuity between the refractive index of the window and that of air or other medium into which the head is inserted. Since the refractive index of the optical window is known and with the head in a known medium such as air, the level of reflection is known. This enables a controller in the console to calculate the round trip loss and thus monitor the loss in the catheter-console interface. Moreover, since round-trip loss is measured, the accuracy is improved by a factor of two over calibration port systems that only measure loss in a single pass arrangement. One embodiment provides for the assessment of a multi-piece catheter using multiple wavelengths.

System and method for assessing catheter connection using return loss

A scanning optical monitoring system and method are appropriate for high speed scanning of a WDM signal band. The system and method are able to identify dropped channels or, more generally, discrepancies between the determined or detected channel inventory and a perpetual inventory for the WDM signal, which perpetual inventory specifies the channels that should be present in the WDM signal assuming proper operation of the network. The system includes a tunable optical filter that scans a pass band across a signal band of a WDM signal to generate a filtered signal. A photodetector then generates an electrical signal in response to this filtered signal. A decision circuit compares the electrical signal to a threshold and a controller, which is responsive to the decision circuit, inventories the channels in the WDM signal.

Optical band scanning monitor system and method

A system and method for fast peak finding in an optical spectrum prioritizes the information it first generates and how the information is then forwarded from the system to a host computer, for example. A spectrum detection subsystem generates a spectrum of an optical signal. An analog-to-digital converter converts the spectrum into sample data. Finally, a data processing subsystem first detects the spectral locations of peaks in the spectrum using the sample data and then uploads the peak information to a host computer before performing processing to determine the shapes of the peaks and/or noise information for the optical signal, for example. The system is thus able to quickly find some information, such as whether or not channels or carriers are present, at what frequency the carriers are operating, and the carriers' power level, and send this information to the host computer. In contrast, information concerning spectral shape or the noise floor sent later in time.

System and method for optical spectrum fast peak reporting

A laser system for a spectroscopic catheter system utilizes an overmoded cavity in order to reduce mode hoping induced power fluctuations during wavelength scanning. In the preferred embodiment, a semiconductor gain medium is used to reduce cost. A fiber pigtail is used to define the laser cavity, which has a tight cavity mode spacing of less that 15 Gigahertz. A diffraction grating is used as the tuning element. A cylindrical lens is used to reduce alignment tolerances and thereby increase manufacturability.

Tunable spectroscopic source with power stability and method of operation

An alignment process for a fiber optic system, which includes at least one lens and a tunable filter element, comprises transmitting an optical signal into the system and detecting a back-reflection from the lens and/or the tunable filter element. The position of the lens relative to the tunable filter element is then manipulated in response to the back-reflection. This alignment prevents the excitation of higher order modes.

Growing community of inventors

Lexington, MA, United States of America

Jeffrey A Korn