Abstract: An encoder system includes a disc coupled to a hub, the disc including a sensible member. The encoder system also includes a sensor operable to cooperate with the sensible member to sense an operating parameter of the disc, and a base assembly movable relative to the hub. A portion of the sensor is coupled for co-movement with the base assembly and movable between a first position in which the portion of the sensor is a first axial distance from the disc and a second position in which the portion of the sensor is a second axial distance from the disc, the second axial distance falling within a desired operating range.

Abstract: Active compensation techniques are used for control of temperature, wavelength, and other characteristics of lasers within a laser array. The laser array includes a plurality of lasers and a plurality of dissipation elements. The dissipation elements can be interstitial to the lasers and can be implemented as non-lasing diodes. The dissipation elements are selectively activated (i.e., turned “on” to dissipate power) to adjust the temperature at the laser junctions. The change in junction temperature allows the lasers to operate at their specified wavelengths. The dissipation elements can be individually controlled and two or more bits of resolution can be provided. Active compensation can be used to adjust (i.e., to compensate) the temperature of selected lasers when one or more lasers are deselected. Active compensation can also be used to adjust (i.e., “tweak”) the wavelengths of the lasers within the laser array to be within their specified wavelengths.

Abstract: Apparatus is provided for the treatment of a medical condition, such as mucositis in patients who are undergoing cancer treatment. The apparatus has several embodiments. In each embodiment, an array of optoelectronic devices, such as light-emitting diodes (LEDs), is used to provide a uniform emission of monochromatic light while producing a minimal amount of heat. The LEDs may be cooled in several ways. The treatments are typically of a very short duration. In several embodiments, selected portions of the patient are treated using a hand-held or stationary lamp. In other embodiments, the entire gastrointestinal tract may be treated simultaneously.

Abstract: A photonic integrated circuit has a multi-wavelength laser array and an active waveguide coupler receiving outputs of the laser array. The active waveguide coupler facilitates high output power coupling of the outputs of the laser array to a single mode optical fiber.

Abstract: An IC laser array package is provided wherein standard CMOS integrated circuit (IC) processes are used for fabricating the controller for the laser array and wherein p-channel MOSFET devices are used as switches with the controller which short the anode of the selected laser in the array (connected to the drain of the p-channel MOSFET switches) to ground. In this structure, the modulating signal from the driver input can be applied to the common cathode substrate of the laser array bar in a standard package, along with a negative dc bias current provided from the negative voltage dc bias package pin through an inductor, in the same built-in bias tee manner previously used with a standard single-laser 14-pin package. Because the p-channel MOSFETs are used only as switches, their ft values are typically not a material hindrance to the circuit operation.

Abstract: The invention provides a system for sensing angular motion. The system includes a light source, a transducing member, and a modulating member having a track of translucent and opaque regions positioned between the light source and the transducing member. The transducing member includes optical receivers spaced across a width larger than or equal to three translucent and three opaque regions. The optical receivers, which may be interlaced across the transducing member, generate a plurality of output signals that form at least one output channel signal. The system may further include a second track of translucent and opaque regions and a second interlaced transducing member. The second transducing member includes a second plurality of optical receivers arranged to generate a plurality of signals that may be used to generate at least one index signal.

Abstract: Active compensation techniques are used for control of temperature, wavelength, and other characteristics of lasers within a laser array. The laser array includes a plurality of lasers and a plurality of dissipation elements. The dissipation elements can be interstitial to the lasers and can be implemented as non-lasing diodes. The dissipation elements are selectively activated (i.e., turned “on” to dissipate power) to adjust the temperature at the laser junctions. The change in junction temperature allows the lasers to operate at their specified wavelengths. The dissipation elements can be individually controlled and two or more bits of resolution can be provided. Active compensation can be used to adjust (i.e., to compensate) the temperature of selected lasers when one or more lasers are deselected. Active compensation can also be used to adjust (i.e., “tweak”) the wavelengths of the lasers within the laser array to be within their specified wavelengths.

Abstract: An IC laser array package is provided wherein standard CMOS integrated circuit (IC) processes are used for fabricating the controller for the laser array and wherein p-channel MOSFET devices are used as switches with the controller which short the anode of the selected laser in the array (connected to the drain of the p-channel MOSFET switches) to ground. In this structure, the modulating signal from the driver input can be applied to the common cathode substrate of the laser array bar in a standard package, along with a negative dc bias current provided from the negative voltage dc bias package pin through an inductor, in the same built-in bias tee manner previously used with a standard single-laser 14-pin package. Because the p-channel MOSFETs are used only as switches, their ft values are typically not a material hindrance to the circuit operation.

Abstract: Phase masks which can be used to make both linear and curved gratings of single or multiple submicron pitches, with or without any abrupt quarter-wavelength shifts (or gradually varying finer phase shifts) simultaneously on the wafer/substrate. The phase masks are made using direct write electron or ion-beam lithography of two times the required submicron pitches of linear and curved gratings on commercially available &pgr; phase-shifting material on a quartz substrate and wet or dry etching of the &pgr; phase-shifting material. The phase masks can be used in connection with making multi-wavelength laser diode chips. The laser diodes have a ridge structure with metal shoulders on either side of the ridge. The laser diode chip, with different wavelength lasers, is bonded and interfaced to a novel microwave substrate that allows for high signal-to-noise ratio and low crosstalk. The substrate is packaged in a low loss rugged housing for WDM applications.

Abstract: An apparatus and method for coupling an array of light beams extending predominantly in one direction into an output port. The light beams are rearranged into a desired shape which extends more equally along two directions than does incident array of light beams. The operation of the rearranging is wavelength insensitive. The rearranged light beams are focused onto the output port. For output ports having a small interface, the focal length of a lens focusing the rearranged light beams to the output port should be as short as possible.

Abstract: Apparatus for use in photodynamic therapy (PDT) is provided having a substantially cylindrical support to which is attached a removable, multi-sided head. Each side of the head has an array of light-emitting diodes that provide monochromatic light to activate a photosensitive dye. The apparatus may be used in invasive surgery to treat brain tumors and the like. The apparatus may be used for topical treatments by providing a removable reflector over the light-emitting head. The temperature of the head is controlled, and the head is cooled by circulating cooling fluid through the head. The use of the cooling fluid allows the LEDs to be driven beyond their rated capacity. The catheter may also include an expandable light diffuser that is affixed over the light-emitting head and that is filled with a diffuser fluid such as a lipid solution. The apparatus may also be used to provide radiant energy to plants or to patients in non-PDT applications.

Abstract: A low cost LED array is formed from a plurality of modular units that are snapped together. Each modular unit consists of one or more U-shaped lead frame substrates which are overmolded with a thermoplastic insulator material. The lead frame substrates act as heat dissipators. The LEDs are then bonded onto the upper surfaces of the lead frame substrates. A reflector unit is separately molded and has one cone-shaped reflector for each light emitting diode. The reflector unit is aligned and affixed to the top of the lead frame unit such that the LED is disposed in the center of each cone. Each of the reflector units has several dovetail-shaped connectors which enable the completed module to be connected to adjacent modules to form the array. The modules are then electrically connected together in series or in parallel according to the particular application. The arrays may be used for plant growth or in photodynamic therapy.