Abstract: A multiplexing/demultiplexing optical device comprises a beam distribution element to receive an input optical signal comprising one or more wavelengths and to distribute the optical signal into a plurality of beams. The optical device also comprises a variable path length element to receive the distributed optical signal from the first optical element, where the variable path length element comprises a plurality path sections, where a length of at least one of the path sections is variable. The optical device further comprises a beam interaction element to receive the plurality of beams from the variable path length element, wherein the plurality of beams are combined and allowed to interfere, and are thereby demultiplexed. A controller operatively coupled to the variable path length element can be provided to programmatically vary the length of one or more of the path sections.

Abstract: An acousto-optical add/drop multiplexer includes an acousto-optical switch including a first optical port coupled to a first polarization splitter, at least one polarization converter coupled between the first polarization splitter and a second polarization splitter, and second and third optical ports coupled to the second splitter. A first circulator is coupled to the first optical port, a mirror is coupled to the second optical port, and a second circulator is coupled to the third optical port. A wavelength selective optical cross-connect may be realized by coupling two such acousto-optical add/drop multiplexers by a single optical fiber to their respective third optical ports.

Abstract: An optical fiber clamp that precisely aligns and clamps multiple optical fibers in multi-channel freespace optical systems, eliminates multiple parts and simplifies assembly. Multiple wafers each having an array of holes passing therethrough, are aligned with respect to each other. Optical fibers are passed through the holes, and at least one of the wafers is moved laterally with respect to the other wafers, so that sidewalls of the holes clamp the optical fibers into a desired location.

Abstract: The present invention includes a method of making a preform for an enhanced photosensitive fiber comprising depositing successive layers of optical material the inside a tube using modified chemical vapor deposition, and collapsing the layers of optical material in a reducing atmosphere with a positive pressure. The present invention also includes a method of making an enhanced photosensitive fiber comprising making a preform using modified chemical vapor deposition wherein the preform is collapsed in a reducing atmosphere with a positive pressure and drawing the preform into a fiber.

Abstract: The present invention relates to a collimator assembly for use in an optical switch. The collimator assembly includes an integrated LED/photodiode plane disposed in a dual microlens array. The integrated LED/photodiode plane results in a relatively simple way to manufacture high port count collimator arrays with integrated monitoring capabilities. The LED/photodiode plane can be readily produced using standard electronics manufacturing technology.

Abstract: An RF tuner and tuning method employs analog quadrature mixing with a coarse-stepwise tunable local oscillator to a near-baseband passband region, followed by A/D conversion of the I and Q signals, correction of phase, group delay, and amplitude errors, image rejection, and translation to baseband by (1) fixed frequency translation, (2) stepwise channelized translation, or (3) essentially continuously variable tuning over a given digital tuning range. The near-baseband passband region is sized and located such that alternating image rejection provides non-redundant and complete tuning coverage of a desired high frequency spectrum with a local oscillator step size equal to about twice the digital tuning range or about twice the number of channels digitally stepwise tunable times the channel width, effectively doubling the typical local oscillator step size.

Abstract: A two-fiber ring architecture capable of carrying multiple wavelength channels and allowing client self-healing of single point failures. The ring architecture includes a two-fiber optical ring carrying at least one wavelength channel, wherein the wavelength channel has working traffic and protection traffic. The optical ring can include a single ring, two interconnected rings, or multiple interconnected rings. Specifically, the ring architecture includes a first client networking element connected to the optical ring by a first pair of 2×2 add drop matrices and a second client networking element connected to the optical ring by a second pair of 2×2 add drop matrices. At least one interconnect node is also provided when more than one ring is used, wherein the interconnect node has a first 2×2 interconnect matrix and a second 2×2 interconnect matrix.

Abstract: The present invention relates to microfluidic devices and to their method of manufacture. The microfluidic devices are original by their specific structure (of sandwich type) and by the materials from which they are made (mainly glasses, glass ceramics, ceramics), and also by their specific method of manufacture, which is based on a vacuum-forming operation. The microfluidic device includes a first assembly including a microstructure and a first substrate, wherein the microstructure is constructed and arranged on the substrate under vacuum. A second assembly includes a second substrate positioned on the microstructure after the first assembly is presintered and adhered thereto by heat treatment to form a one-piece microstructure defining at least one recess between the first and second substrates.

Abstract: Microlens arrays, especially useful for optical coupling in optical switches of fiber optic telecommunications systems are produced with optical quality requisite for such applications with a replicating tool. This tool is made using a form tool set up in a rotating spindle of a precision air bearing milling machine at an angle of inclination such that the point of zero surface velocity is maintained outside of the surface of substrate machined to make the tool for replicating the arrays. The tip of the form tool has a profile corresponding to the profile of the lenses of the array, such as a generally circular profile having a radius centered at the axis of rotation of the form tool. The form tool is reciprocated with respect to the surface so as to form cavities of the desired profile, radius and depth which corresponds each identical lens of the array. To provide arrays the form tool is raised and the substrate is translated to preprogrammed positions.

Abstract: An oxidation and corrosion resistant coating is applied to glass forming equipment by physical vapor deposition. The coating material is preferably aluminum oxide.

Abstract: A method for aligning optical fibers to a lens array is provided, including, providing a planar reflective surface facing the front surface of lens array, locating one end of a fiber adjacent the back surface of the substrate upon which the lens array is formed or integrated to face one of the lenses of the array, propagating light through the fiber and the lens facing the fiber to the planar reflective surface, receiving returned reflected light from the reflective surface through the fiber and the lens facing the fiber, and then adjusting the position of the fiber to change the amount of the returned reflected light received by the fiber to determine when the fiber is at a position which provides a maximum amount or power of the returned reflected light, thereby aligning the end of the fiber to the focal point of the lens. The fiber is attached to the substrate at that position, such as by an adhesive material, and the method repeated for each fiber to a different lens of the array.

Abstract: An optical cross-connect system provides 4×4 switching matrices and self-healing from any single point of failure. The switching matrices route working traffic and redundant protection traffic between a plurality of client network elements and an optical ring. The system also has a client interface for transporting the working traffic and the protection traffic between the switching matrices and the client network elements. The optical cross-connect system further includes a ring interface for transporting the working traffic and the protection traffic between the switching matrices and the optical ring. The switching matrices are structured so that protection is provided from single point failures by electrical switching at the client network element location. This significantly reduces the need for optical switching within the matrices.

Abstract: A non-blocking N×N cross-connect is provided that has an array of liquid crystal (LC) switches in a grid of planar optical waveguides within a light optical circuit (LOC). LC-filled trenches are used in a planar optical waveguide and each trench provides the functionality of a waveguide polarization splitter, a transverse electric (TE) switch cross-point, a transverse magnetic (TM) switch cross-point, or a waveguide polarization combiner. The planar optical waveguide has a refractive index substantially equal to the lowest index of refraction of the LC material. By combining these elements, a cross-connect system is fabricated. Also disclosed is a dynamically adjustable prism constructed with a liquid crystal material.

Abstract: A non-blocking N×N cross-connect is provided that has an array of liquid crystal (LC) switches in a grid of planar optical waveguides within a light optical circuit (LOC). LC filled trenches are used in a planar optical waveguide and each trench provides the functionality of a waveguide polarization splitter, a transverse electric (TE) switch cross point, a transverse magnetic (TM) switch cross point, or a waveguide polarization combiner. By combining these elements, a cross-connect system is fabricated.

Abstract: The disclosed invention includes an amplifier fiber and methods of making the amplifier fiber. One embodiment of the inventive fiber includes a glass core and a glass cladding layer surrounding the glass core. The cladding glass layer has a refractive index which is less than a refractive index of the glass core. The fiber also includes a glass overclad layer surrounding the cladding layer. The overclad layer has a refractive index which is greater than the refractive index of the cladding layer. In another embodiment of the inventive fiber, the overclad layer is doped with an absorber. The absorber strips a mode of light propagating in the cladding from the cladding layer.

Abstract: An optical device which utilizes a photothermal optical effect to achieve switching or attenuation includes a waveguide defined by a waveguide core and a surrounding cladding, wherein the polymer waveguide core includes a region consisting of a photothermally responsive material having an absorption coefficient at a switch wavelength or attenuation wavelength that is higher than an absorption coefficient at a signal wavelength. Switching devices include an optical splitter circuit having a branch that includes the photothermally responsive material, and either a multiplexer for introducing light at the switch wavelength into the optical circuit or a light source focused at the photothermally responsive material. Attenuating devices include a Mach-Zehnder type interferometer having a branch that includes the photothermally responsive material and either a multiplexer for introducing light at the attenuation wavelength into the optical circuit or a light source focused at the photothermally responsive material.

Abstract: A piezoelectric optical switch includes a planar Mach-Zehnder optical device having a piezoelectric rib disposed on one or both of the waveguide structures. The piezoelectric rib deforms the waveguide structure creating a strain vector that alters the optical path of the waveguide. The piezoelectric rib is offset from the propagation path in the waveguide. This yields several important advantages. By positioning the piezoelectric rib away from the waveguide, the strain components in the propagation path of the waveguide in the directions perpendicular to the direction of propagation, e.g., in the x-direction and the y-direction, are negligible. Since strains in these directions create birefringence, elimination of these strains will minimize the birefringence. The elimination or reduction of birefringence is greatly desired because birefringence degrades the extinction ratio at the outputs of the Mach-Zehnder device.

Abstract: An RF tuner and tuning method employs analog quadrature mixing with a coarse-stepwise tunable local oscillator to a near-baseband passband region, followed by A/D conversion of the I and Q signals, correction of phase, group delay, and amplitude errors, image rejection, and translation to baseband by (1) fixed frequency translation, (2) stepwise channelized translation, or (3) essentially continuously variable tuning over a given digital tuning range. The near-baseband passband region is sized and located such that alternating image rejection provides non-redundant and complete tuning coverage of a desired high frequency spectrum with a local oscillator step size equal to about twice the digital tuning range or about twice the number of channels digitally stepwise tunable times the channel width, effectively doubling the typical local oscillator step size.

Abstract: A polarization-interferometry based tunable periodic filter includes polarization defining components such as polarizing beam splitters or polarizing beam displacers located on the input and output sides of a phase retarder such as a birefringent crystal. A polarization independent input consisting of multiple optical channels having a periodic frequency spacing is converted to a branched output of optical channels in which each branch has a periodic frequency spacing that is different from that of the input, and which are interleaved with each other. The output period is tunable by adjusting the phase delay of orthogonal polarization components. A contrast ratio of ≧20 dB can be realized. The device allows the mux/demux of up to 200 WDM channels with a 50 GHz frequency spacing. Applications of the device include a band splitter, a wavelength selective cross-connect, and a wavelength monitor.