Abstract: A waveguide component has a slab waveguide, a rib waveguide, and a mode transition section where the rib waveguide and the slab waveguide are adjacent, and where the rib waveguide is tapered, to provide optical coupling, and lateral confinement rib waveguides are provided along the slab waveguide in the mode transition section to confine light from spreading laterally. The lateral confinement ribs can be formed in the same step with the same mask as used for the taper, to ensure alignment with the taper. They can be arranged either side of the taper. The lateral confinement ribs are significant for enabling a mode transition section which couples with low loss. In particular, it reduces the need for the taper to be so fine, or the taper to be made in both vertical and horizontal axes, both of which cause fabrication difficulties.

Abstract: A laminated optical medium for read-only information recording has ultra-high memory capacity and reliably extracts desired information from laminated memories. Methods for low-cost mass production of laminated read-only medium are demonstrated. The optical medium is a lamination of planar type waveguides made of polymeric materials, in which each waveguide has information recorded as periodic scattering factor to generate scattered light by injection of input light into a waveguide layer. Therefore, read-only information recording medium of ultra-high memory capacity, equivalent to the memory capacity achievable by volume holography, can be produced by using a low-cost planar holographic technique. The laminated medium is simple and energy conserving, because it does not require rotation mechanisms for reproduction of music and video holographic recordings.

Abstract: A homogeneous semiconductor waveguide structure having an undoped core layer and doped cladding layers on both sides of the core layer is proposed wherein the waveguide core is substantially thick providing polarization independence. Because of the cladding layers having low refractive index contrast with respect to the core and being on opposing sides resulting in a substantially symmetrical structure, the waveguide, can be made single-mode with low polarization sensitivity, thus improving characteristics for conducting light therein. Furthermore, the enlarged mode size increases coupling efficiency. Also, since the waveguide is grown from a single semiconductor composition lattice matched to the substrate, wafer uniformity and reproducibility are enhanced. The three layer structure reduces birefringence sufficiently that a yield enhancing etch stop layer can be added to the structure without substantially adverse effects.

Abstract: An optical fiber holder assembly (2) includes a fiber holder (3) and a base (4). The fiber holder is assembled onto the base. The fiber holder is obtained by pressing a unitary sheet metal. The fiber holder has a body (31). Two inclined walls (38) are separately positioned at opposite ends of the body and extending downwardly from the body. Two openings (35) are separately defined in each inclined wall and a passageway formed therebetween. A guide slot (36) is defined in a middle of the body and communicates with the two openings. The fiber holder further includes two flexible portions (32). Each flexible portion has a fixing foot (34) and two opposite supporting arms (33). A clearance (37) is formed between the fixing foot and each supporting arm. The base defines two rectangular openings (41) for receiving the fixing feet.

Abstract: Optical waveguides having a waveguide channel of photosensitive silica glass with a modified refractive index optically written therein, wherein the photosensitive glass comprises oxides of silicon, tin and at least one Group I element, where such optical waveguide devices include optical fiber gratings, optical fiber dispersion compensators, optical fiber sensors, optical fiber lasers, and planar waveguide devices.

Abstract: A main optical path and an auxiliary optical path which are formed in a substrate are optically coupled to each other with a plurality of optical couplers, so as to constitute a Mach-Zehnder interferometer. By controlling the temperature regulation of main and auxiliary optical paths effected by heaters, a control unit regulates the transmissivity of light across an optical input end and an optical output end. Respective optical path lengths of the main and auxiliary optical paths are set so as to lower birefringence when optical loss becomes greater.

Abstract: An optical switch is disclosed that includes a pixel member that moves between a quiescent switch state and an active switch state. An assisted-release mechanism is coupled to the pixel member. It applies a force to the pixel member in the active switch state to enhance the response time of the switch when being reset to the quiescent switch state.

Abstract: A nanophotonic directional coupler is disclosed for transferring light from one waveguide to a second waveguide. The directional coupler is formed within relatively small dimensional parameters and can be formed to accommodate light signals of both transverse electric (TE) and transverse magnetic (TM) polarizations.

Abstract: An improved optical isolator having a pre-aligned first and second collimator and a pre-aligned core assembly joined with the first collimator, the first and second collimators and core assembly all disposed within a housing tube. The core assembly is aligned with and joined directly to the first collimator and fits snugly within the housing tube. The second collimator fits within the housing tube such that it can be aligned with core assembly to minimize insertion loss. The first and second collimators are connected to the housing tube by solder joints, at least one of which is made from a low temperature solder. The core assembly includes a cylindrical permanent magnet, a pair of birefringent wedges and an optical rotator. The optical rotator is joined to a wedge on either side and the combined structure is affixed to the cylindrical permanent magnet.

Abstract: An optical network element uses steerable mirrors in an optical switch to couple optical inputs and optical outputs. An optical switch has at least one array of the steerable mirrors, which can be oriented so as to reflect an optical signal between an input and an output. A shorter optical path between the input and the output reduces optical losses because optical losses in an optical switch using mirrors are directly proportional to the total length of the optical path. Reducing the optical path depends upon the switching tilt angle used in steering the mirrors. But tilting the micro-mirrors near their critical tilt angle or repeatedly across large tilt angles will degrade reliability or control. However, the total optical path can be shortened and the reliability of steerable mirrors can be maintained or increased if at least some of the micro-mirrors in an array are offset angled.

Abstract: An optical processor of a wavelength-division multiplex optical signal includes a non-linear optical device having an active layer containing therein a number of self-organized quantum dots with respective absorption wavelengths. The quantum dots collectively form a continuous optical absorption spectrum in the wavelength range of the wavelength-division multiplex optical signal.

Abstract: An optical fiber collimator array includes an optical fiber array block and a microlens array substrate. The optical fiber array block includes an angled surface and is configured to receive and retain a plurality of individual optical fibers, which carry optical signals. The microlens array substrate includes a plurality of microlenses integrated along a microlens surface and a sloped surface opposite the microlens surface. The microlens surface is coupled to the angled surface such that the optical signals from the individual optical fibers are each collimated by a different one of the integrated microlenses.

Abstract: A method for producing an optical device having a polyimide film through which a light beam is transmitted, which comprises applying a solution containing a polyamic film-forming starting material on a substrate and then baking the resultant under vacuum to form the polyimide film.

Abstract: A cross-connect switch for switching optical signals, in particular, Dense Wavelength Division Multiplexed (DWDM) signals is disclosed. The switch includes a switching matrix for each of the predetermined wavelengths of the DWDM signals. The switching matrices include Micro-Electro-Mechanical (MEM) systems which have optically reflective elements, typically mirrors, arranged in rows and columns for switching an incoming optical signal travelling along a row of such elements to an output port aligned with a column of the elements. The switch has input demultiplexers to split an incoming DWDM signal into its component channel wavelengths, each of which is directed to a switching matrix where it is switched to an output port and recombined into an outgoing DWDM signal by a multiplexer before being transmitted out of the switch. A wavelength-converting switch, connected across the switching matrices, is also included for switching channels between wavelengths.

Abstract: A laser diode module has a laser diode, a lens for condensing the laser beam from the laser diode, an optical fiber for receiving the laser beam from the lens at the end face thereof, and support assembly for supporting the laser diode, the lens, and optical fiber, the support assembly positions the end face of the optical fiber at a deviation position apart from the focal point of the lens by an allowable distance when a temperature of the laser diode module is room temperature and moves the end face of the optical fiber at a close position relatively closer to the focal point than the deviation position when the temperature of the laser diode module rises from the room temperature.

Abstract: A lens for focusing collimated light. The lens includes a single, optically transmissive material having an aspherical focusing surface and a second surface, such that collimated light incident on the aspherical focusing surface is focused in a near-field region of the second surface.

Abstract: An interface system includes separate optical and mechanical interfaces between opto-electronic devices and fibers. This allows each of these components to be optimized for there particular function. This also allows two surfaces to be provided for the optical interface, allowing the opto-electronic elements to be spaced further apart than the fibers. The interface system can be integrated together, used in conjunction with a conventional fiber housing, and can be surface mounted with an electrical interface.

Abstract: An optical switch having a fiber/lens array and a switching substrate may be properly aligned using one or more grating(s) provided on the switching substrate. The grating(s) may be designed to have a predetermined response when the fiber/lens array and switching substrate are properly aligned. For example, the grating(s) may reflect incident light back into an input fiber, where the back-reflected light may be detected. Accordingly, the position of the switching substrate and/or fiber/lens array may be adjusted until back reflected light having predetermined power is detected.

Abstract: The invention has improved parameters when compared iwth prior art devices; pump power was decreased by four orders of magnitude and amplification of signal was increased by two orders of magnitude. The main features of the invention are the following. A nonlinear optical waveguide is made on the basis of a layered MQW-type structure, where unidirectional distributively coupled waves (Ip, Is), e.g. coupled waves having orthogonal polarizations, interact. The wavelength of optical radiation is chosen close to the wavelength of resonance in the structure. Input/output elements, taking into account the asymmetry of the cross section of the nonlinear optical waveguide, are mounted at the input and output of the nonlinear waveguide making up a compact nonlinear-optic module. A small electric current is injected across said nonlinear optical waveguide through electrodes, so as to increase the gain and decrease the pump optical power to a high degree.

Abstract: An apparatus for reshaping optical pulses comprises an N×N optical coupler having N ports on each side of the coupler, where N≦3. An input and an output of the apparatus are defined by two of the N ports on one side of the optical coupler, and a length of optical fibre connects two of the N ports on the other side of the optical coupler. The function of transmission versus input power has a negative gradient at the power level of the optical pulses. By virtue of phase shifts within the coupler, the transmission function is selected such that higher power pulses are attenuated more than lower power pulses, which tends to even out pulse powers to a constant level. This helps maintain a constant signal to noise ratio within a system and can extend the number of optical spans of an optical signal before it requires full electrical regeneration.