Abstract: An optical switch fabric with an input stage, an output stage, and a center stage coupled in a cascaded manner. The center stage includes (1) a minimum number of center switches greater than one that cause the optical switch fabric to be strict-sense nonblocking and (2) at least one additional center switch to provide redundancy for the optical switch fabric. A module is described that includes optical input and output switches coupled to an optical center stage of an optical switch fabric. The module includes an interior cavity that contains free space beams from both the optical input switch and the optical output switch. A method is described for reconfiguring a redundant optical switch into a multilevel optical switch without interrupting operation of the signals carried by the optical switch by adding additional switch components and reconfiguring the fiber interconnection between switch elements.

Abstract: Shaped electrodes for micro-electro-mechanical-system (MEMS) devices to improve actuator performance and methods for fabricating the same are disclosed. The shaped electrodes utilize its three-dimensional geometry to shape an electric field for electrostatic actuation for MEMS devices. For example, the height, width, length, sidewall slope, and layout of the shaped electrodes can be used to provide an optimum electric field in moving a MEMS mirror device. The shaped electrodes can provide electrostatic actuation at a low operating voltage and provide an optimum electric field for maximum tilt or angular range of motion for a MEMS mirror device. The shaped electrodes can be fabricated simply by using a pillar wafer and an electrode wafer. The pillar wafer can be used to form pillars as electrodes, or, alternatively, as barriers. A single substrate can also be used to form pillars and electrodes.

Abstract: An optical switch embodiment includes a switching array of arranged to accomplish switching of input light beams to any of a plurality of output channels and an array of beam monitoring elements for indirectly measuring and providing information used for adjusting output beams. The beam monitoring element further includes means for measuring the angular misalignment and the positional misalignment of a monitor beam and adjusting the reflectors based on monitor beam information such that optical beams are output from the switch having the desired optical characteristics, such as optimized power. Another optical switch embodiment includes an array of rhomboid prism assemblies positioned to receive the output beams from the switching array and such that the beams are split into substantially parallel working and monitor beams.

Abstract: Optical switch packaging techniques and optical switch components are described. In one aspect, an optical switch component that includes a die mounted on an interposer is described. The die has an exposed array of mirrors that can be used as part of an optical switch. Typically, the interposer will also have a fiber array mount arranged to receive a fiber bundle and to position the fiber bundle appropriately over the array of mirrors. In some embodiments, an optical switch can be formed by putting together two mirror image interposer based optical switch components. When placing two interposer based optical switch components together, an alignment frame may be positioned between the interposers to help maintain a desired spacing between the respective arrays of mirrors. In some such embodiments, an inner housing is provided that encloses the dice, the fiber array mounts the alignment frame and portions of the interposers, but leaves connectors mounted on the interposers exposed.

Abstract: A TL1 usage model generator arranged to provide a statistically accurate usage model based upon a particular user profile is described. The TL1 usage model generator is connected to a translator arranged to expand the usage model provided the by TL1 usage model generator into a fully meshed file. Coupled to the translator, a TL1 sequence generator uses the fully meshed file to automatically generate a random sequence of TL1 commands that is provided to an execution engine configured to read the random sequence of TL1 commands. The execution engine, in turn, sends the random sequence of TL1 commands to the system under test (SUT) the results of which are forwarded to and written in a result data base used by a post processor to verify the validity of the system response.

Abstract: The invention provides an optical switch comprising a housing, an input optical fiber, a mirror substrate, an input pivoting mirror, an output optical fiber, a first optical splitter, and a first optical detector. The input optical fiber propagates a light beam and is secured to the housing. The mirror substrate is secured to the housing. The input pivoting mirror is located in a path of the light beam after leaving the input optical fiber. The input pivoting mirror is pivotally secured to the mirror substrate. Pivoting of the mirror relative to the mirror substrate alters an angle with which the light beam is reflected therefrom. The output optical fiber is secured to the housing and has an end through which the light beam enters after being reflected by the input pivoting mirror. The first optical splitter is located in a path of the light beam after leaving the input optical fiber. The first optical splitter splits the light beam into a first propagated portion and a first monitoring portion.

Abstract: The disclosed embodiments include method and apparatus for detecting the alignment of movable reflectors in an optical switch. A diagnostic device embodiment includes a two-dimensional photoimager positioned to receive light from movable mirrors in the switch. Each movable mirror reflects light to different two-dimensional positions on the photoimager based on the position of each movable mirror, thereby creating a two-dimensional image of the reflector array. A controller receives information from the photoimager and adjusts the positions of the movable mirrors according to light received at the photoimager. A related diagnostic device includes an illumination source for directing monitor light beams onto the movable mirrors where the monitor beams are reflected onto the photoimager. This configuration provides two-dimensional information concerning the current position of the movable mirrors which is used to monitor and adjust the positions of the movable mirrors of the switch.

Abstract: A scalable optical switch that uses substrates to multiplex and demultiplex input and output optical signals for optical networks. The switch includes a plurality of input fibers each configured to carry a plurality of lambda signals, a first stack of substrates, each of the substrates coupled to one of the input fibers and configured to demultiplex the lambda signals received on the input fiber by wavelength respectively, a plurality of output fibers, and a switching matrix configured to switch the demultiplexed lambda signals from the first stack of substrates to the plurality of output fibers. In one embodiment, the switch further includes a second stack of substrates coupled between the switching matrix and the output fibers. Each of the substrates of the second stack is configured to multiplex the switched lambda signals onto one of the output fibers respectively.

Abstract: A method for equalizing optical signal power in a group of optical signals transmitted through an optical switch in an optical transmission system. In one embodiment a group of optical signals is input into an optical switch having at least one movable mirror array with a plurality of reflectors formed thereon, the optical beam being directed onto a selected at least one reflector and wherein attenuating the optical beam is accomplished by controllably detuning at least one of the selected at least one reflector to attenuate the optical beam.

Abstract: A method and apparatus are described that may be used to provide decoupled rotation of structures about different pivot points. The apparatus may include one or more fixed blades mounted to a frame or substrate, one or more movable blades mounted to each structure to be moved, and flexures on which the structures are suspended. Separate movable blades may be provided for each degree of freedom. When voltage is applied between the fixed and movable blades, the electrostatic attraction generates a force attracting movable blades toward blades that are fixed relative to the moveable blades, causing a structure to rotate about the flexures. The angle of rotation that results may be related to the size, number and spacing of the blades, the stiffness of the flexures and the magnitude of the voltage difference applied to the blades. The blades are fabricated using deep silicon etching.

Abstract: An apparatus and method of controlling optical loss in an optical switch to equalize optical power or loss in a group of optical signals in an optical transmission system relatively insensitive to mechanical vibration. In one embodiment a group of optical signals is input into an optical switch and selected optical signals are variably attenuated using synchronized control to two mirrors in order to provide more uniform power distribution among the group of optical signals without enhancing vibration sensitivity of the optical switch.

Abstract: A system is provided to obtain loss optimized output optical power by way of feedback control and stabilization in an optical signal switching or routing system. The optical signal switching or routing system includes at least two input optical fibers and at least two output optical fibers, a controllable mechanism for directing an optical beam from one of the input optical fibers to one of the output optical fibers, and a mechanism for measuring the optical power applied to output optical fiber. The measuring mechanism provides a measure of the output optical power through a signal processing apparatus to a control apparatus. Possible other inputs to the signal processing apparatus include the input optical power, test optical power, etc. The inputs to the signal processing apparatus are compared and the signal processing apparatus outputs a signal to the control apparatus to provide optimized output power.

Abstract: A method of moving reflectors in an optical cross-connect switch. In one embodiment, the optical cross-connect switch identifies a reflector path avoiding possible interference with other reflectors, predicts the reflector path from pre-computed tables, and moves the reflector in a straight line in target reflector plane coordinates from initial position to target position.

Abstract: A method for equalizing optical signal power in a group of optical signals transmitted through an optical switch in an optical transmission system. In one embodiment a group of optical signals is input into an optical switch having at least one movable mirror array with a plurality of reflectors formed thereon, the optical beam being directed onto a selected at least one reflector and wherein attenuating the optical beam is accomplished by controllably detuning at least one of the selected at least one reflector to attenuate the optical beam.

Abstract: A method and apparatus hermetically sealing a fiber array block is described. In one embodiment, a fiber array plate is fabricated and an array of tapered holes formed therein. An adhering metal layer, such as a titanium, nickel and gold multilayer, is deposited upon the fiber array plate. A solder preform is positioned on the fiber array plate so that the array of holes in the solder preform corresponds to the array of holes in the array plate. Fibers having an adhering metal layer deposited thereon, are then inserted through the fiber array plate. The tapered holes make the fiber insertion process easier. The fiber array plate is then heated such that the solder preform melts causing the solder to fill any gaps between the fiber array plates and the fiber. When the solder cools a hermetic seal is formed while the fibers remain accurately positioned.

Abstract: An optical cross-connect with integrated optical signal tap is disclosed. In one embodiment, the switch includes two or more optical fiber input ports, lenses to produce collimated beams, one or more optical taps to couple a portion of the optical power from one or more input ports to one or more sample ports, movable mirrors to connect any input port with any output port, two or more optical fiber output ports, and lens to couple collimated beams into the output ports.

Abstract: An optical switch having switch mirror arrays controlled by scanning beams that reduce the amount of electrical connections required and reduce the complexity for constructing large optical switches. Movement of the switch mirror arrays is controlled by one or more scanning beams. The optical switch includes one or more arrays of optical switch inputs and outputs and one or more arrays of movable mirrors to direct light beams from the optical switch inputs to the optical switch outputs. The optical switch also includes one or more control elements to control the movable mirrors based on scanning beams directed to the one or more control elements.

Abstract: An improved photonic switch having optical amplification is described. Signals are amplified before they are switched, after they are switched, or both before and after they are switched. The optical amplification compensates for fixed losses within the switch and transmission system, or provides output power equalization. The photonic switching system includes a demultiplexer for dividing incoming light into different wavelengths or wavebands. The different signals are then supplied to optical amplifiers. The amplifiers amplify the optical signals before supplying them to the optical switch core. Once in the optical switch core, the signals are switched as desired to specified output nodes, then multiplexed back together to provide an output signal from the photonic switching system. In some systems amplification is further provided on the output side.

Abstract: A micro-electro-mechanical-system (MEMS) mirror device includes a mirror component that is capable of moving upon electrostatic actuation. The MEMS mirror device also includes and one or more electrostatic actuators providing electrostatic actuation. The electrostatic actuators having plates disposed approximately perpendicular to the mirror component. The plates are disposed to define a gap between the plates that decreases along a direction perpendicular to a surface of the mirror component.

Abstract: A micromachined apparatus for reflecting light is described that is designed to reduce losses in quality or intensity of light. Mirrors are used having lengths that are longer than their widths to reduce clipping of light when a mirror is located at an angle with respect to light falling thereon. Relatively long mirror torsion components are used to reduce forces required to pivot the mirrors. Regardless of the dimensions of the mirrors and the use of long torsion components, the mirrors are still located relatively close to one another. The relatively close positioning of the mirrors is due to a combined use of notches formed in support frames to which the torsion components are secured, oval shapes of the mirrors which take up less space than rectangular shapes, matching oval openings in the support frames, and the arrangement of the support frames in a non-rectangular array wherein tips of the support frames are located between one another.