Abstract: The present invention comprises an apparatus for performing in-situ elemental analyses of surfaces. The invention comprises an atmospheric electron x-ray spectrometer with an electron column which generates, accelerates, and focuses electrons in a column which is isolated from ambient pressure by a:thin, electron transparent membrane. After passing through the membrane, the electrons impinge on the sample in atmosphere to generate characteristic x-rays. An x-ray detector, shaping amplifier, and multi-channel analyzer are used for x-ray detection and signal analysis. By comparing the resultant data to known x-ray spectral signatures, the elemental composition of the surface can be determined.

Abstract: When embodied in a microgyroscope, the invention is comprised of a silicon, four-leaf clover structure with a post attached to the center. The whole structure is suspended by four silicon cantilevers or springs. The device is electrostatically actuated and capacitively detects Coriolis induced motions of the leaves of the leaf clover structure. In the case where the post is not symmetric with the plane of the clover leaves, the device can is usable as an accelerometer. If the post is provided in the shape of a dumb bell or an asymmetric post, the center of gravity is moved out of the plane of clover leaf structure and a hybrid device is provided. When the clover leaf structure is used without a center mass, it performs as a high Q resonator usable as a sensor of any physical phenomena which can be coupled to the resonant performance.

Abstract: A two-dimensional integrated laser array having a plurality of surface-emitting laser arrays and a plurality of waveguides for optically coupling the individual laser arrays together. Each surface-emitting laser array includes a plurality of injection lasers which are evanescently coupled together in order to emit a single beam of light. The coupling provided by the waveguides causes the surface-emitting laser arrays to operate in phase and at the same wavelength as an external master oscillator. Therefore, the surface-emitting laser arrays generate coherent beams of light, which are combined and focused by a micro-lens. The output of the micro-lens is a single, coherent high-power optical beam which is emitted perpendicular to the two-dimensional integrated laser array.

Abstract: A semiconductor laser array with features providing good beam quality at high powers, first by employing a laterally unguided diffraction region in which light from a set of waveguides is re-imaged in accordance with the Talbot effect and two arrays of waveguides may be used to provide a spatial filtering effect to select a desired array mode. This provides a laser array with increased power per unit solid angle, and with additional advantages of ability to scale the device up to larger arrays, ability to control the electrical excitation of the device for better optimization, and improved modal discrimination. A second aspect of the invention is the use of a resonance condition in an antiguide array, to produce a uniform near-field intensity pattern and improved coupling and device coherence.

Abstract: A semiconductor diode structure including a light-absorbing substrate, an active region, and a pair of cladding layers surrounding the active region. Lasing is inhibited by means of an inclined end facet, which reflects light down into the substrate, where it is absorbed, to provide only one pass of the spontaneously emitted light through the active region. One disclosed embodiment has a conventional end facet for the out-coupling of edge-emitted light. Another embodiment includes a surface-emitting facet formed in an opening in the substrate adjacent to the inclined facet. Yet another embodiment has two inclined facets. One inclined facet may serve to reflect light into the absorbing substrate, or both may serve to reflect light through separate surface emitting facets.

Abstract: An ion milling method is disclosed that provides a manufacturing technique for mass producing microscopic surface features using a wide variety of media that includes semiconductors, metals, and glasses. In the preferred embodiment, vertical and 45 degree mirrors are formed simultaneously in semiconductor laser diodes in order to produce monolithic two dimensional arrays of surface emitting lasers. Standard double heterostructure semiconductor laser diodes are first grown on a wafer using metalorganic chemical vapor deposition techniques. An ion milling gun is oriented at a particular angle from the longitudinal axis of the active layer of the laser and emits a stream of atomic particles toward the lasers producing a generally two sided cut or notch that extends downward from the top surface of the semiconductor laser and traverses the active layer.

Abstract: An array of semiconductor lasers formed in a single substrate and having parallel waveguides that terminate in a wide diffraction region fabricated with the array structure. The diffraction region has a curved reflective surface selected to achieve a desired degree of coupling among the elements of the array, and to enhance and stabilize a preferred lateral mode of oscillation.

Abstract: A diffraction-coupled semiconductor laser array, and a related method for its operation, the array structure having a diffraction section that is electrically controllable independently of a waveguide section having multiple laser channels. Above a critical level of injected gain in the diffraction region, and with appropriate selection of channel and diffraction region dimensions, stable operation in the in-phase supermode results, with adjacent lasers operating in phase and a single-lobed far-field distribution pattern being produced. Below the critical level of injected gain, the out-of-phase supermode or multimode operation is favored and the narrow single peak of the far-field pattern is no longer present. This mode switching can be used to rapidly modulate operation of the array without directly switching it on and off.