Abstract: A wavelength monitoring system for continuously monitoring the wavelengths of different optical channels transmitted through a wavelength division multiplexed (WDM) fiberoptic system. In one construction, an optical diffraction grating is used to disperse the light being monitored onto a rotating polygon having mirrors on the facets thereof, such that the rotating polygon reflects the light onto a detector located behind a slit. In a second construction, the light is projected onto a rotating, hollow transparent cylinder having a thin film filter deposited on a surface thereof, wherein the thin film filter comprises a Fabry-Perot structure which has a gap which varies as a function of its position on the rim of the cylinder, such that the varying gap allows for a varying transmission wavelength which varies as a function of angular position. A detector is positioned in the interior of the cylinder to detect light passing through the rotating thin film filter.

Abstract: A method and an automated apparatus for three-dimensional optical alignment of optical components for testing or assembly purposes comprise use of a visible light vision system to assist active alignment of optical components based on the measured optical output at a wavelength of light outside of the visible range.

Abstract: A compact wavelength monitoring and control assembly for a narrow band (i.e., laser) source is provided, comprising two narrow bandpass, wavelength selective transmission filter elements of Fabry-Perot structure through which two separate collimated beams from a laser source are directed onto two photodetectors. The spacing of the multiple transmission maxima for one etalon is chosen to match that of the desired set of frequencies to be used for locking purposes. The spacing of the transmission maxima for the second etalon is used, in combination with a dielectric filter, to generate a wavelength fiducial to denote an absolute frequency. The spacing of the second etalon is chosen to be much wider than the frequency grid etalon. A control circuit processes the simultaneously acquired signals from the two detectors as the laser wavelength is varied.

Abstract: An external cavity laser tuner. One embodiment constructed according to principles of the invention includes a cantilever interposed between the laser cavity mirrors or operating as a mirror. Another embodiment constructed according to principles of the invention includes a torsional mirror interposed between the laser cavity mirrors or operating as a mirror. A further embodiment constructed according to principles of the invention includes a torsional filter interposed between the laser cavity mirrors. An additional embodiment constructed according to principles of the invention includes an electrooptic prism interposed between the laser cavity mirrors.

Abstract: A method is provided for fabricating microelectromechanically tunable vertical-cavity surface-emitting lasers and microelectromechanically tunable Fabry-Perot filters with precise lateral and vertical dimensional control. Strained reflective dielectric film(s) are applied to a multiple quantum well structure to electronically band-gap-engineer the quantum wells. Appropriate strain in the reflective dielectric film layers is also used to create appropriate curvature in one of the reflective dielectric film stacks so as to form a confocal cavity between a planar reflective dielectric film layer and the curved reflective dielectric film layer in the vertical cavity surface emitting laser or filter. Laser and filter structures are also provided which include a suspended membrane structure made of a dielectric/metal membrane or metal film that supports a cavity-tuning reflective dielectric film stack while being anchored at the perimeter by metal support post(s).

Abstract: Novel light switches and attenuators are disclosed. In one form of the invention, a novel 2×2 crossbar switch is formed by positioning a movable reflector intermediate four fiberoptic lines. In another form of the invention, a 1×N switch is formed by providing a plurality of cantilevers each having a reflective surface thereon. In still another form of the invention, a novel light attenuator is formed by positioning a movable arm intermediate two fiberoptic elements.

Abstract: A fiber connector that facilitates alignment of and electrical communication with electrooptical devices on an optical fiber or interposed between optical fibers. An embodiment of in-line optoelectronic device packaging constructed according to principles of the invention includes a ferrule configured to receive an optical fiber with an optoelectronic device mounted on one end of the ferrule, for alignment with the fiber. Electrically-conductive deposits along the side of the ferrule supply electrical energy to or conduct electrical signals from the optoelectronic device. The optoelectronic device-carrying ferrule is inserted in a ceramic sleeve. Another ferrule, maintaining another optical fiber, also is inserted in the ceramic sleeve. Another embodiment constructed according to principles of the invention includes a second optoelectronic device mounted on the second ferrule.

Abstract: An electrically tunable Fabry-Perot structure using a deformable multi-layer mirror construction wherein Ga1−aAlaAs, where a <0.1, is used as the sacrificial layer which may be selectively removed using a citric acid enchant. The multi-layer mirrors consist of N and M period of quarter wavelength layers where N and M are integers, or integers plus 1/2. Further, the mirrors are made from alternating layers of Ga1−xAlxAs, where X>0.96, and a material selected from the group consisting of either Ga1−zAlzAs, where 0.7>Z>0, or Ga1−yAlyAs/Ga1−zAlzAs/Ga1−yAlyAs, where 0.7>Z>0 and y>0.5. The Ga1−xAlxAs is wet oxidized by exposing its edge to water in a nitrogen or helium atmosphere at a temperature of between about 360° C. and 450° C. so as to transform it to AlOx. The resulting AlOx layers abut the sacrificial layer and act as etch stops during the formation of a cantilever Fabry-Perot structure by etching of the sacrificial layer.

Abstract: A tunable microelectromechanical optical filter is placed in a linear laser cavity and is tilted at a large enough angle to prevent the unwanted reflections from coupling back to the mode of the cavity. Front and back mirrors form the cavity with a lens matching the mode of the gain media to that of the tuning element. The gain media can be a semiconductor, a solid state crystal or a fiber based region. In another preferred embodiment, the invention includes a ring cavity geometry with clockwise laser oscillation. In this case, the surface of the tunable microelectromechanical filter can be perpendicular to the direction of laser oscillation since the unwanted reflection may be prevented from coupling to the cavity mode by the action of an isolator.

Abstract: An external cavity mirror for use in a semiconductor laser, the external cavity mirror comprising a waveguide formed on a substrate of highly electro-optic material, and including electrically-operated means for determining the reflectance attributes of the external cavity mirror.

Abstract: An optically addressed spatial light modulator (OASLM), and an optical pattern processor employing the same. An embodiment of the OASLM includes a transparent electrode; a buffer layer; a detector region; and a modulator region, wherein the detector and modulator regions are optically isolated and resist electron movement therebetween. In one embodiment, the detector region includes a photoconductive semiconductor region with a higher band gap than the modulator region and the modulator region comprises a low-photoconductive semiconductor material.

Abstract: A tunable laser and method for operating the same, wherein the tunable laser utilizes a tunable Fabry-Perot filter as its wavelength-selective component. In one form of the invention, the tunable laser is characterized by the provision of optical elements (hereinafter referred to as "optical operators" or just "operators") on either side of the tunable Fabry-Perot filter, whereby the tunable Fabry-Perot filter can be set at a right angle to the optical path of the laser without introducing reflection problems interfering with the optimum lasing.