Abstract: A method for generating optical paths in a photonic network is provided. A model of a photonic network is used to store relationship information that describes the relationships between photonic network elements, as well as configuration information about the elements of the photonic network. A path manager receives a request to generate one or more paths based on an input port and one or more output ports. Using the information stored in the photonic network model, the path manager generates one or more candidate paths.

Abstract: Signals employed to align and cause dithering via MEMS mirrors in an optical cross connect switch are manipulated to impose, on the optical beam (steered via the MEMS mirrors) amplitude modulation and in particular a time-varying set of induced mirror angles that yield a desired time history of optical power level that is modulated according to a digital code in the amplitude modulation pattern. The controlled time sequence expressed as a time-varying optical power level can be used for in-band signaling along the same optical channels available for conventional optical data. The amplitude modulated signal is conveyed through the cross connect switch and is useful for example in control and command of the cross connect switch.

Abstract: In a multiple-axis free-space-coupled single-mode fiber-optic transmission system, such as an optical cross-connect switch, a method and apparatus are provided for the closed loop attenuation of optical beam power signals employed to align and cause dithering via MEMS mirrors which are manipulated to impose on the optical beam frequency modulation and, in particular, a time-varying set of induced mirror angles that yield a desired time history of optical power level that is modulated according to a digital code in the frequency modulation pattern.

Abstract: Signals employed to align and cause dithering via MEMS mirrors in an optical cross connect switch are manipulated to impose, on the optical beam (steered via the MEMS mirrors) amplitude modulation and in particular a time-varying set of induced mirror angles that yield a desired time history of optical power level that is modulated according to a digital code in the amplitude modulation pattern. The controlled time sequence expressed as a time-varying optical power level can be used for in-band signaling along the same optical channels available for conventional optical data. The amplitude modulated signal is conveyed through the cross connect switch and is useful for example in control and command of the cross connect switch.

Abstract: A method for generating optical paths in a photonic network is provided. A model of a photonic network is used to store relationship information that describes the relationships between photonic network elements, as well as configuration information about the elements of the photonic network. A path manager receives a request to generate one or more paths based on an input port and one or more output ports. Using the information stored in the photonic network model, the path manager generates one or more candidate paths.

Abstract: A MEMS-based mirror is provided with trenches between adjacent electrodes in order to be able to withstand relatively high applied voltages, and thus has a substantially reduced exposure to uncontrolled surface potentials. The MEMS-based mirror, thus avoids voltage drifts and has an improved mirror position stability. The trench dimensions are selected such that the voltage applied between each adjacent pair of electrodes stays within predefined limits. An insulating layer, such as silicon dioxide, electrically isolates each pair of adjacent electrodes. Each insulting layer extends partially above an associated trench and is characterized by the same height and width dimensions.

Abstract: An array of MEMS devices is formed on a planar substrate having in each of a plurality of annular regions or sectors a plurality of MEMS mirrors of substantially identical structure, wherein the MEMS mirrors in each region have an identical pre-tilt. The pre-tilt is achieved by embedding each dual-axis tiltable mirror within a pre-tilted microplatform or gimbal. In a specific embodiment, one microplatform of a preselected pre-tilt is provided for each micromirror and an underlying electrode is provided having a shape conforming with the pre-tilt. In a specific embodiment, the annular regions are contiguous elliptical or ovoidal regions. By pre-tilt, it is meant that the rest state or nonactuated state of the micro-mirror is such that a reflected beam from a fixed source is directed to the center of a target array.

Abstract: A MEMS-based mirror is provided with trenches between adjacent electrodes in order to be able to withstand relatively high applied voltages, and thus has a substantially reduced exposure to uncontrolled surface potentials. The MEMS-based mirror, thus avoids voltage drifts and has an improved mirror position stability. The trench dimensions are selected such that the voltage applied between each adjacent pair of electrodes stays within predefined limits. An insulating layer, such as silicon dioxide, electrically isolates each pair of adjacent electrodes. Each insulting layer extends partially above an associated trench and is characterized by the same height and width dimensions.

Abstract: One or more cavities are formed in the bonding surfaces of one, all, or some of the elements to be bonded. These cavities serve as receptacles for the bonding material and are where the bonds are localized. The cavities are of sufficient size and shape so that their volume is greater than the volume of bonding material forming the bond. This ensures that when the elements are brought into contact with one another to mate, the bonding material, which can flow prior to solidifying into a bond, will flow into the cavities and will not impede the separation of the parts. This allows the parts to be mated with nominally zero separation. Once solidified, the bonding material forms a localized bond inside each cavity. Different cavity shapes, such as, rectangular, circular, or any other shape that can be injected or filled with adhesive material may be used.

Abstract: An array apparatus has a micromachined SOI structure, such as a MEMS array, mounted directly on a class of insulative substrate, such as low temperature co-fired ceramic or a thermal-coefficient of expansion matched glass, in which is embedded electrostatic electrodes disposed in alignment with the individual MEMS elements, where the electrostatic electrodes are configured for substantial fanout. In a specific embodiment in order to compensate for differences in thermal-expansion characteristics between SOI and ceramic, a flexible mounting is effected by means of posts, bridges and/or mechanical elements which allow uneven expansion in x and y while maintaining z-axis stability. Methods according to the invention include fabrication steps wherein electrodes are fabricated to a post-fired ceramic substrate and coupled via traces through the ceramic substrate to driver modules.

Abstract: In a gimbaled micromachined micromirror array optimized for parallel-plate electrostatic operation, longitudinal-type gimbal hinge elements are provided in which a plurality of torsional longitudinal hinge elements are arranged in an array parallel to the axis of rotation and which are linked together by rigid lateral brace sections. In primary embodiment the hinge elements are arranged in a double gimbal configuration. Specific embodiments of the hinge elements are simple longitudinal, compound longitudinal, stacked simple longitudinal, and stacked compound longitudinal. The longitudinal hinges may be used with various types of mirrors including circular or rectilinear, recessed or nonrecessed, where the hinges are connected in either a symmetric or asymmetric configuration relative to one another, as hereinafter illustrated by way of a subset of examples.

Abstract: An optical switch globally minimizes maximum tilt angles used to route optical signals from input to output by disposition of an input array of first tiltable micromirrors within a first boundary typically having top-bottom reflection symmetry and left-right reflection symmetry and by disposition of an output array of second tiltable micromirrors within a second boundary a symmetry which matches the symmetry for the input array, the output array and the input array being disposed opposing one another and normal to parallel central axes and further being offset from one another in the plane of the normals to the arrays, so that a collimated beamlet impinging on the center the input array and reflected off at an equivalent angle intersects the output array at an offset.

Abstract: A MEMS device having a fixed element and a movable element wherein one or the other of the fixed element and the movable element has at least one radially-extended stop or overdeflection limiter. A fixed overlayer plate forms an aperture. The aperture is sized to minimize vignetting and may be beveled on the margin. Overdeflection limitation occurs during deflection before the movable element can impinge on an underlying electrode. The overdeflection limiter may be conveniently placed adjacent a gimbaled hinge.

Abstract: In an electrostatically controlled deflection apparatus, such as a MEMS array having cavities formed around electrodes and which is mounted directly on a dielectric or controllably resistive substrate in which are embedded electrostatic actuation electrodes disposed in alignment with the individual MEMS elements, a mechanism is provided to mitigate the effects of uncontrolled dielectric surface potentials between the MEMS elements and the electrostatic actuation electrodes, the mechanism being raised electrodes relative to the dielectric or controllably resistive surface of the substrate. The aspect ratio of the gaps between elements (element height to element separation ratio) is at least 0.1 and preferably at least 0.5 and preferably between 0.75 and 2.0 with a typical choice of about 1.0, assuming a surface fill factor of 50% or greater. Higher aspect ratios at these fill factors are believed not to provide more than marginal improvement.

Abstract: An array apparatus has a micromachined SOI structure, such as a MEMS array, mounted directly on a class of insulative substrate, such as low temperature co-fired ceramic or a thermal-coefficient of expansion matched glass, in which is embedded electrostatic electrodes disposed in alignment with the individual MEMS elements, where the electrostatic electrodes are configured for substantial fanout. In a specific embodiment in order to compensate for differences in thermal-expansion characteristics between SOI and ceramic, a flexible mounting is effected by means of posts, bridges and/or mechanical elements which allow uneven expansion in x and y while maintaining z-axis stability. Methods according to the invention include fabrication steps wherein electrodes are fabricated to a post-fired ceramic substrate and coupled via traces through the ceramic substrate to driver modules.

Abstract: In an electrostatically controlled deflection apparatus, such as a MEMS array having cavities formed around electrodes and which is mounted directly on a dielectric or controllably resistive substrate in which are embedded electrostatic actuation electrodes disposed in alignment with the individual MEMS elements, a mechanism is provided to mitigate the effects of uncontrolled dielectric surface potentials between the MEMS elements and the electrostatic actuation electrodes, the mechanism being raised electrodes relative to the dielectric or controllably resistive surface of the substrate. The aspect ratio of the gaps between elements (element height to element separation ratio) is at least 0.1 and preferably at least 0.5 and preferably between 0.75 and 2.0 with a typical choice of about 1.0, assuming a surface fill factor of 50% or greater. Higher aspect ratios at these fill factors are believed not to provide more than marginal improvement.

Abstract: In a folded three-dimensional free-space optical switch including a set of fibers and an optical system for producing collimated beamlets aligned to intersect an array of dual axis micromirrors of coplanar input and output mirror elements, and a folding mirror, the input and output micromirrors are arranged in a pattern wherein either the input or output mirror set is disposed along an annulus and wherein the complementary output or input mirror set is disposed within the annulus in order to globally minimize maximum tilt angles for a two-dimensional locus of tilt angles of the micromirror set. The beamlets are routed from assigned input fibers to corresponding input moveable mirrors to assigned output fibers via the static folding mirror and corresponding output moveable mirrors.

Abstract: Apparatus and methods are provided for driving a two-axis MEMS mirror using three non-contact actuation elements or electrodes. A differential bi-directional mirror control uses unipolar drive voltages biased at a suitable value. Transformation functions map two-axis tip-tilt commands to three actuation drive signals for selected electrode orientations and sizes.

Abstract: Methods and apparatus are provided for the closed loop attenuation of optical beam power in a multiple-axis free-space-coupled single-mode fiber-optic transmission system. In a specific embodiment involving two tip-tilt mirrors to couple optical power from an input fiber to an output fiber, the four mirror axes arc actuated in such a way as to produce either a static or time-varying set of induced mirror angles that yield a desired time history of optical loss. The attenuation technique uses the DC level of the measured output power to adjust the amplitude of the induced mirror angles.

Abstract: In an electrostatically controlled apparatus, such as a MEMS array having cavities formed around electrodes and which is mounted directly on a dielectric substrate in which are embedded electrostatic actuation electrodes disposed in alignment with the individual MEMS elements, a mechanism is provided to controllably neutralize excess charge and establish a controlled potential between the MEMS elements and the electrostatic actuation electrodes.