Abstract: A wavelength-dispersive device for processing a multi-channel optic signal, the device including an optic chip defining first and second diffraction gratings coupled via a first free propagation region, the second diffraction grating coupled at its output end to an array of light-receiving elements via a second free propagation region, each light-receiving element positioned to selectively receive a respective channel of the multi-channel signal, and wherein the first free propagation region includes a spatial filter defined by selective doping of the optic chip so as to preferentially transmit a selected portion of the output from the first diffraction grating to the second diffraction grating and thereby reduce cross-talk at the array of light-receiving elements.

Abstract: A silicon rib waveguide device includes a mode filter section serially connected to a curved rib section. The curved section has a width large enough to support multimode transmission while the filter section has a straight waveguide of smaller rib width supporting only single mode transmission. A tapered section connects the curved section to the straight section and an outwardly tapered waveguide is connected to the opposite end of the straight section.

Abstract: A fiber block for connecting optical fibers to an optical device comprises a lithographically defined front face and a plurality of recesses for optical fibers extending linearly from the front face in a plane which is substantially perpendicular to the front face, at an angle within that plane which is non-perpendicular to the front face. It is preferred that the block is essentially rectangular with recesses for the optical fiber formed in it in a non-perpendicular arrangement. The block is preferably formed as two mating parts each with aligned recesses on their mating faces, thereby to permit an optical fiber to be held in a pair of recesses one on each part. The recesses can end with a locally narrower portion which acts as an end stop for the fiber thereby to permit it to be located accurately. The recesses are preferably V-grooves and the block is preferably of silicon.

Abstract: In electronic apparatus, a coaxial signal cable is connected to a semiconductor circuit using a coaxial connector 24 to convert the coaxial signal to a coplanar wave (CPW) mode, the CPW mode signal being transferred from the connector 24 to the circuit 27 via a flexible connection 23 comprising a CPW transmission line 25 on a flexible substrate 26.

Abstract: A method of fabricating an integrated optical component on a silicon-on insulator chip comprising a silicon layer (1) separated from a substrate (2) by an insulating layer (3), the component having a first set of features, eg a rib waveguide (5) at a first level in the silicon layer (1) adjacent the insulating layer (3) and a second set of features, eg a triangular section (5B) at a second level in the silicon layer (1) further from the insulating layer (3), the method comprising the steps of: selecting a silicon-on-insulator chip having a silicon layer (1) of sufficient thickness for the first set of features; fabricating the first set of features in the silicon layer (1) at a first level in the silicon layer; increasing the thickness of the silicon layer (1) in selected areas to form a second level of the silicon layer (1) over part of the first level; and then fabricating the second set of features at the second level in the silicon layer (1).

Abstract: A method of forming an integrated chip optical device as a protective layer formed over part of the face of the chip on which at least one optical waveguide is formed, and the protective coating is selectively removed leaving the coating over an edge region 18 and the edge of the device is polished to provide high edge quality against which offchip optical fibers may be abutted.

Abstract: A method for holding an end of at least one optic fibre in alignment for optical communication with an end of a respective optic element at a side edge of an optic chip; the method including the steps of: providing a fibre support supporting at least one optic fibre; assembling the fibre support and the optic chip so as to align the end of the at least one optic fibre with the end of the respective optic element at the side edge of the optic chip, wherein the fibre support includes a first portion that is configured to extend beyond the side edge over the optic chip when the end of the at least one optic fibre is aligned with the end of the respective optic element at the side edge; and then bonding said first portion of the fibre support to the optic chip to secure the fibre support to the optic chip.

Abstract: A system (10) comprises a carrier (1) which is adapted to carry an optical fiber (9) and an optical chip (3) having a circuit element (4). The carrier and the optical chip are provided with co-operable alignment features (13,14) for aligning the carrier with the optical chip so that the optical fiber and the circuit element are optically coupled.

Abstract: An optical chip (10;110) has a surface (3;103) with an edge (7;107), an optical component (5;105) disposed on the surface spaced from the edge and an optically conductive element (33;133) extending from the optical component to the edge through which the optical component is able to be optically coupled with an optical fiber (25).

Abstract: A device 102 incorporating a sensor 106 for sensing a temperature of the device and/or a local heater 106 for the provision of heat to a minority area within the device, wherein the sensor and/or the local heater comprises at least one semiconductor element 302,804 which is fabricated as part of the device.

Abstract: An optical interface arrangement includes a tile carrying an optical component which is mounted substantially at right angles to a closely adjacent circuit board which carries an electrical circuit. The circuit board has an electrically conductive track extending to an edge of the board adjacent to an edge of the tile. The edge surface of the tile has a localized recess carrying an electrically conductive material which extends across the thickness of the tile and along a major surface of the tile to connect with the optical component. A short bondwire is provided which links the electrically conductive material in the recess to the adjacent electrically conductive track on the circuit board.

Abstract: In one aspect of the invention there is provided a retainer (150) for retaining a first section of an elongate element (13) of generally curvilinear cross section in a mounting channel (18) which extends along a surface (24) of a first side of a substrate (23) from an edge (25) at which a second side (27) of the substrate inclines away from the first side in a first direction.

Abstract: A rib waveguide structure comprising a layer (4) of light conductive material defined between two planar faces with a rib (9) formed on one of the faces and an optical components e.g. a tapered waveguide (6) optically coupled to the other face. An inverted rib waveguide comprising a light conductive layer (11) and a rib (10) that projects from the light conductive layer (11) into a substrate (4, 8) is also described as well as other optical devices comprising a light conductive layer separated from a substrate by a non-planar layer (3) of light confining material and optical devices comprising two or more layers (2, 3; 18, 19, 20) of light confining material buried within a rib with a light conducting component (10; 17; 22) at least a part of which is formed between planes defined by the two layers of light confining material. A method of forming such devices is also described.

Abstract: An optical coupling between first and second optical components 1, 8 in which an input face 2A through which light is to pass of the first component 1 being directly bonded to an output face 8C through which light is to pass of the second component 8. Such a coupling may be provided, for example, between a rib waveguide 2 and an optical fibre 7.

Abstract: An optical waveguide structure formed on an optical chip comprising a first waveguide layer 3 of a first material supported on a substrate 7 and a second waveguide layer 6 of a second material supported on the first waveguide layer 3. The first waveguide layer 3 is separated from the substrate 7 by an optical confinement layer 8 and the second waveguide layer 6 is separated from the first waveguide layer 3 by an etch-stop layer 9. The etch-stop layer 9 is thin compared to the thickness of the first waveguide layer 3 and/or the second waveguide layer 6 and is of a material which enables it to act as an etch-stop when features are etched in the second waveguide layer 6.

Abstract: An electro-optic device is disclosed for altering the density of charge carriers within an integrated optical waveguide. The device includes a substrate, and an integrated optical waveguide extending across the substrate with two doped regions being provided such that an electrical signal can be applied across the doped regions to alter the density of charge carriers within the waveguide. The doped regions can each include a plurality of doped areas spaced apart from each other along the length of the waveguide.

Abstract: An isolation device that can be used for providing optical and electrical isolation between areas of an integrated chip. The isolation device includes three doped elongate regions which form diodes which can be connected in series. The isolation device can be used in optical devices or optical attenuators.

Abstract: A method of controlling birefringence in a rib waveguide structure manufactured in silicon, the rib waveguide structure comprising an elongated rib element having an upper face and two side faces, the method comprising forming a layer of thermal oxide to a predetermined thickness on said upper face and side faces of at least a portion of said rib waveguide structure.

Abstract: An hermetically sealed fiber optic gyroscope assembly has loops of optic fiber on a support ring in a sealed casing comprising a base plate, a perimeter wall upstanding from the base plate and a cover secured to the perimeter of the wall, together with optical circuitry located within the casing for directing light around the optic fibre loops together with electrical connecting circuitry passing from the optical circuitry to external terminals in sealed engagement with the casing.

Abstract: The optical component (4) is mounted on an optical chip in alignment with an optical fibre (1) which is mounted within a V-groove (2) formed in the chip, the optical component (4) has two non-parallel location surfaces (4A, 4B) which abut against corresponding location features (5, 6) on the chip to locate the component (4) in a first direction (Y-axis) substantially perpendicular to the plane of the chip and in a second direction (Z-axis) which is perpendicular to said first direction (Y-axis) and substantially perpendicular to the length (X-axis) of the V-groove (2), and the optical component (4) is mounted on the chip so as to overhang one end (2A) of the V-groove to enable the end (1A) of the optical fibre (1) to be brought into a close, abutting relationship with the component (4).