Bae Systems Information and Electronic Systems Integration Inc.

Chris L Willis

Adam J Marcinuk

Paul R Moffitt

Eugene M Lavely

Jonathan R Takahashi

Daniel J Creeden

John C McCarthy

Katherine J Snell

Michael S Richman

Amrita V Masurkar

Jonathan K Tong

Michael E Knotts

A multi-axis rotary actuator includes a payload support configured to be rotatable about a first axis, a disk surrounding at least a portion of the payload support, and an elevation wheel rotatably coupled to the payload support. The disk is configured to be rotatable about the first axis. The elevation wheel is configured to be in contact with the disk and to be rotatable about a second axis perpendicular to the first axis. The actuator can include a mirror or other device coupled to the elevation wheel. The mirror or other device is configured to be rotatable about the first axis and the second axis as the payload support and the elevation wheel rotate about the first axis and the second axis, respectively.

Multi-axis actuator with differential drive

A system and method for imaging a sample having a complex structure (such as an integrated circuit). The sample is placed on a motion system that moves the sample with respect to an electron beam generator that is used in imaging the sample. The motion system affords thirteen degrees-of-freedom for movement of the sample, by providing a rotation stage, a fine 6-axis piezoelectric-driven stage, and a coarse 6-axis hexapod stage. Various detectors gather information to image the sample. Interferometric and/or capacitive sensors are used to measure the position of the sample and motion system.

Sample manipulation for nondestructive sample imaging

A system and method for imaging a sample having a complex structure (such as an integrated circuit) implements two modes of operation utilizing a common electron beam generator that produces an electron beam within a chamber. In the first mode, the electron beam interacts directly with the sample, and backscattered electrons, secondary electrons, and backward propagating fluorescent X-rays are measured. In the second mode, the electron beam interrogates the sample via X-rays generated by the electron beam within a target that is positioned between the electron beam generator and the sample. Transmitted X-rays are measured by a detector within the vacuum chamber. The sample is placed on a movable platform to precisely position the sample with respect to the electron beam. Interferometric and/or capacitive sensors are used to measure the position of the sample and movable platform to provide high accuracy metadata for performing high resolution three-dimensional sample reconstruction.

Nondestructive sample imaging

Techniques and architecture are disclosed for controlling the temperature of a fiber laser system. In some embodiments, a single thermoelectric cooler (TEC) may be utilized to control the temperature of multiple system components. In some embodiments, a TEC may be physically/thermally coupled to a laser diode, which in turn may be physically/thermally coupled with a mounting plate to which one or more fiber grating holders are physically/thermally coupled, and an optical fiber that is operatively coupled with the laser diode may be physically/thermally coupled with the one or more fiber grating holders. In some embodiments, this may provide a thermal pathway/coupling between the optical fiber (e.g., its fiber grating(s)), and the TEC. In some embodiments, this may reduce/minimize the quantity of temperature control components, reduce system size/complexity, increase system dependability, and/or increase system performance/efficiency. Numerous configurations and variations will be apparent in light of this disclosure.

Temperature control of a fiber laser system

Techniques are disclosed for fabricating optical instrumentation. The techniques can be used, for instance, to populate an optical bench with several optics that can be simultaneously bonded and simultaneously verified to precise assembly, and without the use of adjustable mounts or active alignment. The techniques may be embodied, for instance, in a jig designed for operatively coupling to a given optical bench. The jig includes cut-outs that identify placement locations for the various optical components on the underlying optical bench. Thus, once the jig is secured to the optical bench, precise placement of the optical components is simplified. In some such embodiments, the jig further includes a clamping assembly for each cut-out, so that once an optical component is placed on the optical bench via that cutout, the clamping assembly can be engaged to hold that optical component in place while a deposited bonding agent is cured.

Rapid optical assembly via simultaneous passive bonding

An X, Y positioning unit, mount or fixture is designed to adjust the position of an optical element mounted in the fixture so as to move it laterally and vertically with respect to the optical axis of the element, such that, once adjusted, the position is maintained through the clamping of plates about the positioning fixture to lock the hinges against movement. In this manner the adjusted position of the optical element is locked in by van der Wall forces exerted by the plates on the fixture, with the locking technique not affecting the alignment. In one embodiment, the fixture includes live hinges which join an optical element holder to a fixed plate and pivot the holder about orthogonal axes crossing at the center of an optical element holder.

Ultra stable optical element x,y, positioning unit for use in harsh environments

Techniques for switching an optical element from one path to another, where each path has high dimensional stability in a harsh thermal and dynamic environment, are disclosed. In one particular embodiment, the optic is mounted on a rotable platform. A spring mechanism preloads the platform against a hard stop, thereby providing accurate and repeatable placement of the optic in its deployed position. The motor's actuator arm is the only element whose position is sensed, allowing the switching system to work without requiring highly precise position feedback. In the stowed position, the spring mechanism operates as a firm tension cable, thereby securing the optic out of the laser beam path.

Optic switching mechanism

A system is provided for nulling out or eliminating alignment errors in an optical system by moving a lens to capture and center a collimated beam laterally-shifted by thermal excursions, thus to couteract the boresight error caused by the thermally-induced lateral shifting. As a result, alignment error the thermal coefficient of expansion characteristics of the optical elements and their mounting systems caused by lateral off-sets is corrected by moving a lens or lens system in response to thermal changes in a direction which moves the lens so that the collimated light impinging on the lens is made to come in on the optical axis of the lens.

Method and apparatus for eliminating alignment error in an optical system

An optical system with improved boresight stability having optical elements and a beam expander oriented on a chassis, wherein the beam expander is mounted for minimal movement. By minimizing movement of the beam expander, the angular error of a laser beam travelling through the optical system and subject to various angular tilt errors is reduced by an amount inversely proportional to the magnification ratio of the beam expander based on optical principles. In one embodiment the beam expander is mounted on a highly stiff location on the chassis and away from thermal stresses. Another embodiment is to mount the beam expander to a structural support of a higher assembly. The present invention isolates the beam expander from the instability of individual optical elements and from deformation of the optical bench that impairs the performance and diminishes benefits otherwise gained from the optical principles.

Boresight stability of an optical system

Optical bench mounting and thermal management techniques are disclosed that enable increased dimensional stability. Output power, beam divergence, and boresight stability of the laser are thus maintained. A separate optical bench is pseudo semi-kinematically mounted to a chassis. A number of heat dissipation or heat management techniques can be utilized for heat generating components on the bench. For example, hot components (e.g., laser crystals) can be mounted on a cryo-cooler or other heat-pump, or attached to the chassis instead of the bench. Thermal loads can be balanced across the thickness of the bench to minimize bowing of the bench, and thermal strapping can be used to conduct heat away from hot components mounted on the bench to other locations (e.g., chassis or elsewhere) where the heat can be more efficiently handled. Thermal insulators and thermal damming can be used to inhibit heat flow from components into specific bench locations.

Athermal optical bench

An apparatus for mounting optical components and adjusting its orientation with respect to the optical axis of other components in an optical system. In one embodiment, the multi-axis gimbal mounting apparatus utilizes a single piece main structure having a pair of live hinges and a locking feature that enhances two kinds of stability. First, the adjustable elements of the mount remain in the intended position when the locking mechanism is actuated with minimal cross-talk between the locking features and the adjustment features. Second, the adjustable elements of the mount remain in the intended position when the mount or the system in which it resides is exposed to extreme environmental perturbations of vibration, temperature, shock, and acceleration. This mount is suitable for use in military laser systems, cryogenic systems, and other industrial optical instruments subjected to harsh environments such as aircraft, ship, and battlefield deployed devices. Furthermore, the mount is compact, easy to adjust, has high resolution and flexibility for optical component mountings, and is easily manufactured.

Growing community of inventors

Hollis, NH, United States of America

Chris L Willis