Abstract: A method of processing a semiconductor wafer that has circuits in each of a plurality of regions sectioned by a plurality of streets on the front surface and has a coating layer formed on the front surface having the circuits to a predetermined thickness, the method comprising a stress-reducing step of reducing the stress of the coating layer by forming a plurality of grooves in the coating layer formed on the front surface of the semiconductor wafer; and a grinding step of processing the back surface of the semiconductor wafer by grinding to a predetermined thickness after the stress-reducing step.

Abstract: Improvements in an electro-optic modulator with a segmented optical transmission network with a series of discrete electrodes for successive segments of the network include drivers at the output of a corporate feed into the modular transmission line. The penalty of ?N suffered from division of the input power is thus avoided. Respective modulating signals are supplied to the electrodes along the transmission lines whose lengths differ from each other, so that modulating signals arrive at their respective electrodes in synchronism with the propagation of an optical signal through the optical transmission network. The differential loss in the different feed line lengths in the corporate feed are compensated by adjusting the gains of the amplifiers or by incorporating additional attenuation in the legs of the corporate feed.

Abstract: A set of three gratings may be operated in a vernier loop fashion to select a particular wavelength from a wavelength division multiplexed system. As a result, an optical add/drop multiplexer may be provided that can be tuned to select a desired wavelength. In one embodiment, the tuning may be done thermo-optically.

Abstract: Single-mode and multi-mode fibers to achieve modal splitting and greater sensitivity in an optical fiber coupler for evanescent-wave biosensor applications. A source of light having multiple modes is coupled to the input to one of the multi-mode fibers, with the geometry of necked-down section being such that a limited number of modes may be carried by the multi-mode fiber as the light emerges from the coupler. At least one of the single-mode fibers is supported adjacent the multi-mode fiber to receive and carry one of the limited modes. A biomolecule enveloped by the evanescent field, exhibits a direct or indirect affinity to a binding partner, such that attachment of the binding partner is at least partially responsible for the limited number of modes carried by the multi-mode fiber as the light emerges from the coupler.

Abstract: A low-loss integrated optical coupler includes at least three substantially similar optical couplers, adjacent ones of the optical couplers interconnected via at least one set of waveguides, each of the sets of waveguides comprising a path-length difference between the waveguides therein. In one embodiment of the present invention, the multi-section optical coupler comprises at least two arms and the path-length differences are adjustable such that signals traversing the at least two arms undergo a relative phase shift, such that a desired output power splitting ratio for the multi-section optical coupler is achieved. Alternatively, the optical coupler is implemented in an inventive optical device that functions at least, as an optical switch or an optical splitter.

Abstract: An optical coupling system for use with multiple wavelength optical signals provides improved coupling efficiency between a free-space optical beam and a relatively thin, surface layer of an SOI structure (“SOI layer”), allowing for sufficient coupling efficiency (greater than 50%) over a predetermined wavelength range. An evanescent coupling layer, disposed between a coupling prism and an SOI layer, is particularly configured to improve the coupling efficiency. In one embodiment, the thickness of the evanescent layer is reduced below an optimum value for a single wavelength, the reduced thickness improving coupling efficiency over a predetermined wavelength range around a defined center wavelength. Alternatively, a tapered thickness evanescent coupling layer may be used to improve coupling efficiency (or a combination of reduced thickness and tapered configuration).

Abstract: Adjustable filters formed in fibers or waveguides based on evanescent coupling, where a coupling layer is formed between a waveguide overlay and a side-polished coupling port on the fiber or waveguide. A control mechanism may be provided to adjust a property of at least one of the waveguide overlay and the coupling layer to adjust the output of the filter.

Abstract: Apparatus using mechanically-actuated evanascent wave coupling. At least a portion of an optical waveguide is integrated onto a substrate, and an optically active element is physically moved relatively to each other, with the result that propagation parameters for the waveguide are substantially altered. The optically active element may be a resonator or another waveguide. Altered propagation parameters can be used to cause an optical wave to be transformed in response to an electromagnetic signal. Physical parts of the apparatus can vary widely in both size and tolerance. The optically active element is mechanically actuated relative to a position of the optical waveguide.

Abstract: An optical module of the present invention includes a first substrate 1, a second substrate 2, a PD 3, a LD 4, and an optical fiber 5. The first substrate 1 has a first optical waveguide core 1c formed therein. The second substrate 2 has a second optical waveguide core 2c formed therein. The first optical waveguide core 1c and the second optical waveguide core 2c form an optical connecting portion where the first substrate 1 and the second substrate 2 are bonded to each other. The LD 4 is capable of transmitting an optical signal via the second optical waveguide core 2c and the optical fiber 5. The PD 3 is capable of receiving an optical signal which enters the second optical waveguide core 2c from the optical fiber 5, and propagates through the first optical waveguide core 1c via the optical connecting portion formed between the first optical waveguide core 1c and the second optical waveguide core 2c.

Abstract: Whispering gallery mode optical resonators which have spatially-graded refractive indices. In one implementation, the refractive index spatially increases with a distance from an exterior surface of such a resonator towards an interior of the resonator to produce substantially equal spectral separations for different whispering gallery modes. An optical coupler may be used with such a resonator to provide proper optical coupling.

Abstract: An alignment device includes an alignment member with one or more waveguide-alignment grooves, resonator alignment grooves, and/or an alignment groove for a second optical element such as a modulator. The various alignment grooves reliably establish and stably maintain evanescent optical coupling between the optical elements positioned therein. A method for assembling a resonant optical power control device may include: fabricating an alignment member with the alignment grooves; positioning and securing the optical elements in corresponding alignment grooves for optical coupling therebetween. Alignment grooves in the substrate and/or in one or more of the optical elements are fabricated at proper depths and positions and preferably with mating grooves and/or flanges to enable optical coupling without extensive active alignment procedures.

Abstract: Methods and apparatus for depolarizing light are disclosed. A disclosed apparatus includes a waveguide, a first microresonator and a second microresonator. The first microresonator has a first birefringence and is evanescently coupled to the waveguide. The second microresonator has a second birefringence different than the first birefringence and is also evanescently coupled to the waveguide. A disclosed method includes evanescently coupling a first portion of input light into a first microresonator, rotating the polarization of the first portion to create a first recirculated portion, and evanescently coupling the first recirculated portion into a waveguide. The disclosed method further includes evanescently coupling a second portion of input light into a second microresonator, rotating the polarization of the second portion to create a second recirculated portion, and evanescently coupling the second recirculated portion into the waveguide.

Abstract: An optical structure for combining light from a plurality of individual optical fibers into a single optical transmission device. The structure can be incorporated into the optical probe of a spectrophotometric instrument and includes a plurality of optical send fibers having input and output ends and an optical light mixer having input and output ends. The output ends of the send fibers are secured in optical communication with the input end of the light mixer.

Abstract: A fiber-ring optical resonator comprises a transverse segment of an optical fiber differing from adjacent segments in at least one physical property (e.g., diameter, density, refractive index, chemical composition, etc) so that it may support a resonant circumferential optical mode and enable evanescent optical coupling between the circumferential mode and an optical mode of a second optical element. The resonator may be fabricated with alignment structure(s) for enabling passive alignment of the second optical element for evanescent coupling, and/or with structure for suppressing undesired modes and/or resonances. A fiber-ring resonator may form a portion of a resonant optical filter or modulator. A plurality of optically-coupled fiber-ring resonators (formed on one or more fibers) may provide tailored spectral properties.

Abstract: A method for cylindrical processing of an optical medium, including optical fiber and optical materials of substantially cylindrical form. The method of the preferred embodiments includes the steps of rotating an optical medium about a longitudinal relative rotation axis thereof relative to a processing tool; spatially selectively applying the processing tool to a portion of a surface of the optical medium in operative cooperation with relative rotation of the optical medium and the processing tool, thereby producing a patterned (i.e., spatially selective) structural alteration of the optical medium, the pattern including altered, differentially-altered and unaltered portions of the optical medium. Specialized techniques for spatially selectively generating the structural alteration may include masking/etching, masking/deposition, machining or patterning with lasers or beams, combinations thereof, and/or functional equivalents thereof.

Abstract: This application teaches systems and techniques that use an optical coupler and a film for evanescently coupling light to or from an optical or electro-optical device. The film is connected to the coupler surface as a spacer for setting the distance between the optical coupler and the optical or electro-optical device.

Abstract: A microresonator is provided that incorporates a composite material comprising a polymer matrix and nanoparticles dispersed therein. The microresonator includes the composite material having a shape that is bounded at least in part by a reflecting surface. The shape of the microresonator allows a discrete electromagnetic frequency to set up a standing wave mode. Advantageously, the polymer matrix comprises at least one halogenated polymer and the dispersed nanoparticles comprise an outer coating layer, which may also comprise a halogenated polymer. Methods for making composite materials and microresonators are also provided. Applications include, for example, active and passive switches, add/drop filters, modulators, isolators, and integrated optical switch array circuits.

Abstract: An optical waveguide coupler relaxes a phase matching condition and facilitates coupling between an optical waveguide and a resonator. Light in a multimode optical waveguide is coupled directly to a microsphere resonator via evanescent light. Under a nonresonance condition, influence of the microsphere resonator is small, and light propagation through the multimode optical waveguide is not influenced. However, since the intensity of the light stored in the microsphere resonator is high under the resonance condition, even if the coupling efficiency is low, the microsphere resonator outputs light of approximately the same power as that of the light in the multimode optical waveguide. Therefore, a strong coupling condition is always satisfied, and the optical waveguide coupler functions as a filter due to the interference between the light in the multimode optical waveguide and the light that has passed through the microsphere resonator.

Abstract: A resonant optical filter includes first and second transmission waveguides and a resonator (including one or more evanescently coupled resonator segments). The resonator supports at least one circumferential resonant mode and is evanescently coupled to the waveguides. An optical signal entering the filter through a waveguide and substantially resonant with the resonator is transferred to the other waveguide, while an optical signal entering the filter and substantially non-resonant with the resonator remains in the same waveguide. Multiple resonator segments may be formed on a common resonator fiber and positioned for enabling coupling between them, resulting in a tailored frequency filter function. The resonators may include alignment structure(s) (flanges, grooves, etc) for enabling passive positioning and/or supporting first and second transmission waveguides, such as optical fiber tapers.

Abstract: A hybrid and tapered waveguide coupler that has two different single-mode waveguide sections for light at two different wavelengths to couple light at the two different wavelengths into or out of an optical device located in a reach of an evanescent field of the guided optical energy in the waveguide coupler.

Abstract: A photon operating device is capable of more effectively using five senses and muscular or other functions humans have, and capable of performing various kinds of information processing as high-level interface connecting image information of natural worlds and human brains. The photon operating device comprises a plurality of first optical fibers, a plurality of second optical fibers, which both are arranged in form of a grating on a two-dimensional plane, semiconductor lasers and CCD line sensors, which both are disposed at one-side ends and the other ends of the first optical fibers, respectively. A photon beam introduced from a light source into one end of a selected first optical fiber is divided into two correlated dual signals, i.e. a first signal traveling through the selected first optical fiber and a second signal led out from the selected first optical fiber externally of the two-dimensional plane, at an intersection between the first and second optical fibers by an optical switch.

Abstract: A two-dimensional photonic crystal slab apparatus having a waveguiding capability is provided. Noncircular holes are introduced to replace the circular holes in the two-dimensional lattice of the photonic crystal to provide waveguiding capability. Waveguide bends and splitter using noncircular holes with high transmittances are described for symmetry planes of the two dimensional lattice structure.

Abstract: A wavelength-selective optical device for coupling of light at predetermined wavelength from one optical fiber waveguide to another using at least two gratings and cladding-mode assisted coupling is disclosed. The transfer of light is performed using intermediate coupling to one or more cladding mode of the waveguides. In the case when the fibers have physically different cladding's, an arrangement for transfer of light from one cladding to another is required. The disclosed coupler has no back-reflection, small insertion loss, and very high channel isolation. The device can be used in wavelength-division multiplexing networks.

Abstract: The interior surfaces of the holes in holey optical fibers has adsorbed optically material which may be detected by propagating laser light down the axis of the fiber and detecting Raman, Infrared, or visible fluorescence or absorption.

Abstract: An optical switch comprises a substrate, first and second optical waveguide, and first and second conducting elements. The first optical waveguide is coupled to the substrate. The first conducting element is coupled to the first optical waveguide. The second optical waveguide is coupled to the substrate. The second conducting element is coupled to the second optical waveguide. In operation, a first electrical bias applied between the first and second conducting elements causes the first optical waveguide to not optically couple to the second optical waveguide. Further in operation, a second electric bias applied between the first and second conducting elements causes the first optical waveguide to optically couple to the second optical waveguide.

Abstract: An optical switch for routing light between two waveguides is disclosed. The switch, or router, comprises a movable waveguide, the movable waveguide having two positions, wherein in a first position the movable waveguide is interposed between the two waveguides and transmits light between the two waveguides by evanescent wave coupling, and in the other position the movable waveguide is retracted from the two waveguides and is not transmitting light between the two waveguides. Means for moving the movable waveguide between the two positions is also disclosed. The optical switches are used in M×N optical routing arrays being capable of directing light from any one of the M input ports to any one of the N output ports with additional ADD/DROP functions.

Abstract: A microchip may include an optical signal routing system. The optical routing system may include a distribution waveguide coupled to a light source and signaling waveguides interconnecting source and destination locations. A directional coupler may be used to couple and modulate light from the distribution waveguide to a signaling waveguide at a source location. A photodetector may be used to convert light signals from the source location into electrical signals at the destination.

Abstract: An integrated photonic apparatus that includes a glass substrate having a major surface, a first waveguide segment and a second waveguide segment, and a folded evanescent coupler connecting the first waveguide segment to the second. The folded evanescent coupler is formed by a first length of the first waveguide segment and an equivalent length portion of the second waveguide running parallel and adjacent to the first waveguide segment. The first length is substantially equal to one half of an evanescent-coupler length needed to transfer a first wavelength in a non-folded evanescent coupler. A reflector (e.g., dielectric mirror that is highly reflective to light of the first wavelength and also highly transmissive to light of a second wavelength) is located at an end of the folded evanescent coupler. The first length is selected to transfer substantially all light of a first wavelength.

Abstract: An optical coupling system for use with multiple wavelength optical signals provides improved coupling efficiency between a free-space optical beam and a relatively thin, surface layer of an SOI structure (“SOI layer”), allowing for sufficient coupling efficiency (greater than 50%) over a predetermined wavelength range. An evanescent coupling layer, disposed between a coupling prism and an SOI layer, is particularly configured to improve the coupling efficiency. In one embodiment, the thickness of the evanescent layer is reduced below an optimum value for a single wavelength, the reduced thickness improving coupling efficiency over a predetermined wavelength range around a defined center wavelength. Alternatively, a tapered thickness evanescent coupling layer may be used to improve coupling efficiency (or a combination of reduced thickness and tapered configuration).

Abstract: A practical realization for achieving and maintaining high-efficiency transfer of light from input and output free-space optics to a high-index waveguide of sub-micron thickness is described. The required optical elements and methods of fabricating, aligning, and assembling these elements are discussed. Maintaining high coupling efficiency reliably over realistic ranges of device operating parameters is discussed in the context of the preferred embodiments.

Abstract: At technique for holding a resonator relative to an optical fiber at a specified distance. Structures including a rectangular indentation may be formed in the end of the optical fiber. The resonator may be placed against edges of the structures, to hold a different portion of the resonator spaced from an area where the waveguide modes will emanate.

Abstract: A bridge fiber and a method of connecting two other dissimilar optical waveguide fibers is presented. The bridge fiber may be utilized to connect positive dispersion fibers or step index single mode fibers to compensative fibers, such as dispersion compensation fibers or dispersion-slope compensation fibers.

Abstract: A method of placing a fiber on a substrate includes holding at least one fiber under tension, aligning the held fiber with a groove formed into a substrate, moving the substrate towards the fiber to place the fiber in the groove, fixing the position of the fiber under tension in the groove, and releasing the fiber.

Abstract: An infrared absorption spectrometer features an optical microcavity, and a waveguide that evanescently couples light into the microcavity. The optical resonance frequency of the microcavity is tuned to coincide with an atomic or molecular resonance frequency of a selected atom or molecule. In this way, light coupled into the microcavity will experience absorption in the presence of an atomic or molecular subtance. The absorption causes a measurable change in the evanescent light coupling into the microcavity. The detection sensitivity of the spectrometer is significantly increased, compared to prior art spectrometers, because of the high Q value of the microcavity and the ensuing long optical path lengths of the resonant modes traveling within the microcavity.

Abstract: An exemplary embodiment of the present invention is an apparatus for providing optical interprocessor communication. The apparatus comprises a multichip module and an optical module. The multichip module includes a substrate, an integrated circuit electrically connected to the substrate and a hermetically sealed cover. The hermetically sealed cover encloses a sealed portion of the substrate and the integrated circuit is inside of the sealed cover. The optical module includes an optical transceiver located on the substrate outside of the sealed portion and the optical transceiver is electrically connected to the integrated circuit through the substrate.

Abstract: The optical fiber tap establishes optical communication between a branch optical fiber and a main optical fiber and includes a housing, a serpentine main channel and a branch channel. The main channel is defined in the housing and is shaped to accommodate part of the main optical fiber. The main channel includes a coupling curve portion shaped to define a main coupling curve in the main optical fiber. The branch channel is also defined in the housing and is shaped to accommodate part of the branch optical fiber. The branch channel communicates with the main channel at the coupling curve portion of the main channel. Optical signals couple laterally between the main optical fiber located in the main channel and the branch optical fiber located in the branch channel. Optical communication between the optical fibers is therefore established.

Abstract: Fiber tap monitors formed on side-polished fiber coupling ports based on evanescent coupling.

Abstract: An optical device comprises a substrate having at least one light-guiding core and cladding material surrounding the core; a cladding-modifying element disposed alongside, at least in part, a portion of the light-guiding core, the cladding-modifying element being formed of a material different to the cladding material so that the refractive index difference between the material of the cladding-modifying element and the cladding material is dependent upon the temperature of the cladding-modifying element; and a heating and/or cooling arrangement for altering the temperature of the cladding-modifying element.

Abstract: A system and methods for performing calorimetric testing which includes a micro resonator that supports a plurality of whispering gallery mode resonant frequencies, a first waveguide that receives light and evanescently couples whispering gallery mode resonant frequencies from the first waveguide into the micro resonator, and a second waveguide evanescently coupled to the micro resonator such that a portion of the whispering gallery mode resonant frequencies are coupled out of the micro resonator and into the second waveguide. The system can also include a light source for providing a multitude of optical resonances and a reader for analyzing the resonances received from the second waveguide.

Abstract: The objective of the present invention is the detection/monitoring of microorganisms present in the air, water or foodstuffs through the use of a fiber optic biosensor with an evanescent-field. A first concretization of the present invention concerns a method for detection of contamination by specific microorganisms through the use of the evanescent-field of a sensitive fiber optic characterized by stages of: a) exposing the evanescent-field of the sensitive fiber optic using an appropriate technique based on physical and chemical properties; (b) permitting immediate contact of the exposed evanescent-field obtained in the stage (a) with the sample to be examined, with the aforementioned sample having a form adequate so as to obtain the generation of an optical signal in response to the presence of microorganisms in the sample; and, (c) demodulating the optical signal generated in stage (b) and using this value to quantify the microorganisms through an appropriate method.

Abstract: An improved optical interconnect structure, system including the structure, and method of forming the structure and system are disclosed. The optical interconnect structure includes a waveguide and a reflective structure. Either the waveguide, the reflective structure, or both include a curved surface to facilitate focusing of light transmitted between the waveguide and an optoelectronic device.

Abstract: A method for incorporating an optical material into an optical fiber and optical devices utilizing the method are disclosed. Fiber material may be removed from the optical fiber to expose the fiber core and the core may then be at least partially removed. The optical material may then be incorporated into the core area to replace the removed core. Cladding material may then be deposited over the optical material and an electrode may be fixed to the cladding over the optical material to form an optical device.

Abstract: Methods and apparatus for depolarizing light are disclosed. A disclosed apparatus includes a waveguide, a first microresonator and a second microresonator. The first microresonator has a first birefringence and is evanescently coupled to the waveguide. The second microresonator has a second birefringence different than the first birefringence and is also evanescently coupled to the waveguide. A disclosed method includes evanescently coupling a first portion of input light into a first microresonator, rotating the polarization of the first portion to create a first recirculated portion, and evanescently coupling the first recirculated portion into a wave guide. The disclosed method further includes evanescently coupling a second portion of input light into a second microresonator, rotating the polarization of the second portion to create a second recirculated portion, and evanescently coupling the second recirculated portion into the waveguide.

Abstract: An optical switch for routing light between two waveguides is disclosed. The switch, or router, comprises a movable waveguide, the movable waveguide having two positions, wherein in a first position the movable waveguide is interposed between the two waveguides and transmits light between the two waveguides by evanescent wave coupling, and in the other position the movable waveguide is retracted from the two waveguides and is not transmitting light between the two waveguides. Means for moving the movable waveguide between the two positions is also disclosed. The optical switches are used in M×N optical routing arrays being capable of directing light from any one of the M input ports to any one of the N output ports with additional ADD/DROP functions.

Abstract: Fiber optical devices formed on substrates fabricated with grooves that operate based on evanescent optical coupling through a side-polished fiber surface in each fiber involved.

Abstract: Waveguide photodetector apparatus and methods employing an optical waveguide having a tapered section, which may be horizontally tapered, vertically tapered, or both. The apparatus also includes a photodetector with an intrinsic region, which in one embodiment may be tapered in a manner corresponding to a horizontal taper of the tapered section. The photodetector is arranged adjacent the tapered section such that the intrinsic region is coupled to the optical waveguide via an evanescent wave of a guided lightwave. The tapered section serves to force energy carried in the guided lightwave from the optical waveguide into the intrinsic region of the photodetector via the evanescent wave, thereby shortening the photodetector length.

Abstract: Optical coupler apparatus having reduced geometry sensitivity includes spaced apart first and second main waveguides having a coupling section. In one embodiment, first and second side waveguide sections are arranged in the coupling section adjacent outer sides of the first and second main waveguides to allow evanescent coupling between the main waveguides and side waveguide sections. Methods of fabrication and operation are also described.

Abstract: Fiber optical devices formed on substrates fabricated with grooves that operate based on evanescent optical coupling through a side-polished fiber surface in each fiber involved.

Abstract: An optical resonator accelerometer includes an optical microcavity and an optical waveguide that evanescently couples light incident on an input end of the waveguide core into the high-Q WGMs of the microcavity at a coupling efficiency of over 99%. The waveguide includes a waveguide core, and a multi-layer dielectric stack that has alternating high and low refractive index dielectric layers. The reflectivity of the dielectric stack is sufficient to isolate the waveguide core and the microcavity from the substrate. A flexure has a first end mounted to the substrate, and a second end arranged to interact with said optical microcavity. The flexure is responsive to an inertial input to cause a change in the coupling geometry between the microcavity and the optical waveguide.

Abstract: The charge of pixels in a FPA array is retrieved by propagating an optical wave through a waveguide to interact with pixel charges from the FPA. An optical detector receives an optical wave altered by the respective pixel charges as it travels. The optical wave is sensed after passing through the waveguide. In a preferred embodiment, separate waveguides interact separate optical waves with charge from FPA pixels. Information concerning the charge is obtained with separate optical waves in the separate waveguides. In a preferred example of an N×M array according to an embodiment of the invention, a complete frame of data includes only N+M data values. A direct memory is also provided, where the pixel charges are held by maintaining an electric field to the pixels making the charge retrievable by an optical wave multiple times until the electric field is removed or reduced.