Abstract: The invention discloses multi-channel fiber Bragg grating (FBG) interrogation systems and manufacture thereof. The multi-channel fiber Bragg-grating sensor interrogation unit comprises at least one integrated optic sensor microchip and a signal processing IC-electronics unit in a miniaturized, telecommunications standard, hermetically sealed 2-cm×5-cm SFF single fiber package.

Abstract: A method of preventing particles of elastomeric material employed as seals or spacers in a sanitary piping system from entering the product stream, comprising applying an effective amount of comminuted iron powder to the elastomeric base material prior to forming said material into said seals or spacers, magnetically sensing said particles in said piping system; and responsive to said magnetic sensing diverting a portion of said product stream containing said particles.

Abstract: An assembly for providing a concentrated, vertically stacked array of laser beams from a horizontally offset array of electrically serially-connected metallic microchannel heat sinks each bearing a laser diode bar. The heat sinks are mounted on horizontally offset planes of the manifold which has coolant channels serving adjacent heat sinks that are separated from each to increase the electrical resistance of the fluid path between adjacent ones of said heat sinks. Stepped optical deflectors re-arrange the horizontally emitted laser beams into vertical stack.

Abstract: An electrochromic device is achieved that exhibits the characteristics of impact-resistant safety glass by starting with a solid electrolyte sheet material and a peripheral sealant material sandwiched between substrates to heat and pressure such that the electrolyte bonds to the treated surfaces of the substrates with an adhesion of at least 1.8 kg/linear cm width causing the electrolyte to exhibit a tensile strength of at least 5 kg/cm2.

Abstract: A method of suppression of Indium carry-over in the MOCVD growth of thin InGaAsP quantum wells, with low Indium content, on top of thick GaInAsP, with high Indium content. These quantum wells are essential in the stimulated emission of 808 to 880 nm phosphorous-based laser structures. The Indium carryover effect is larger in large multi wafer reactors and therefore is this invention focused on large multiwafer MOCVD reactors. This invention improves the quality of the quantum well, as measured by photo-luminescence spectra and uniformity of wavelength radiation.

Abstract: A gasket for use with sanitary piping systems contains a receptacle for retaining an encapsulated bacterial test indicator. The receptacle has a length that permits the indicator end of the test indicator to be directly exposed to the sterilizing steam that is introduced into the piping system. The gasket is preferably installed at the sanitary flange of a short “bull” T-section of the stainless steel sanitary piping and secured thereto by a stainless steel cap. The stainless steel cap is recessed to accommodate as much of the test indicator length as may be required to position the indicator end of the test indicator in the central lumen of smaller pipe diameters.

Abstract: A DFT is used to compute the magnitude and phase of the frequencies desired to be detected in a frame of sampled data by performing 2 dot products for each such frequency. The two dot products are calculated using the samples in the frame and an equal number of equally spaced cosine and sine coefficients for each frequency to be detected.

Abstract: A laser bar is soldered to a conventional microchannel copper heat sink whose coefficient of thermal expansion (CTE) is locally modified in the area where the laser bar is soldered to better match the CTE of the laser bar. A strip of ceramic material having a CTE lower than that each of the laser bar and of the copper heat sink is soldered to portions of the metallic heat sink located adjacently to the surface area on which the laser bar is located. The inclusion of the ceramic strips enables a laser bar having a nominal CTE of 6.6×10?6/K, to be soldered directly to a copper heat sink having a nominal CTE of 16.5×10?6/K without incurring thermal distortions at the interface that would limit the useful life of the laser bar.

Abstract: A wafer that is cleaved to provide a facet for a Fabry-Perot cavity is provided with Bragg gratings whose axes are offset by a small angle from the axis of the Fabry Perot cavity to offset the effect of the randomly uncontrollable location of the cleaved facet on the optical phase of the grating feedback.

Abstract: A method of preparing a multi-layer, crack resistant sol-gel glass derived coating on a substrate by removing the outer periphery of each layer before curing the layer and depositing any succeeding layer.

Abstract: A gasket for establishing a seal between the flanges of sanitary pipe fittings having a lumen of pre-determined diameter which comprises an O-ring portion of elastomeric material and an incompressible ring member bonded to said O-ring portion, said ring member having a substantially flat cross-section to limit compression of the O-ring.

Abstract: A high speed optical receiver comprises, in combination, a non-imaging light gathering device for directing light from its entrance pupil to its exit pupil according to the edge ray principle and a photonic detector coupled to the exit pupil and having an anti-reflective micro-structured active surface area dimensioned to minimize capacitance effects commensurate with achieving a desired signaling speed.

Abstract: A fiber optic clamp assembly for use with an ultra-precision translation stage to precisely align a fiber optical bundle with a laser diode mounted in a sealable enclosure, comprising a housing for receiving the fiber bundle, a flexible seal positionable between said housing and said enclosure; and a pressure collar for urging the seal against the enclosure, said collar being freely movable within the housing so as not to load the translation stage when the housing is being moved by the translation stage to align said bundle with said laser diode and thereafter being movable to compress the flexible seal without disturbing the alignment.

Abstract: A laser diode bar, solder preform and heat sink are assembled prior to reflowing the solder in a manner to prevent molten solder from being drawn by capillary action over the light emitting end of the diode bar. A recessed pin 30 locates the ends of the laser bar and solder preform with respect to an edge of the heat sink so that the laser bar and solder preform overhang the heat sink edge by respective amounts. When molten, the solder will not be drawn by capillary action to obscure the light emitting end of the laser diode bar.

Abstract: A DBR grating may be created in the cladding of a wafer by defining a non-gain window area, advantageously at the end of the wafer. The non-gain area may be defined either by removing all layers above the cladding layer at the window portion or, preferably, by halting the MOCVD process once the cladding layer has been created and by selectively removing from a portion of the cladding layer a protective coating, advantageously of SiO2, Si3N4, or a metal, to define the window area. A photo resist is applied, and the wafer is exposed to interfering laser beams to create a grating pattern in the photoresist, conveniently without the need for any particular effort to confine either the photoresist or the interfering beams solely to the window area. The photoresist is developed and an etchant used to transfer the pattern into the cladding layer.

Abstract: A laser diode stack includes a serially connected plurality of laser diode bars mounted on heat sinks. Connected in parallel with each laser diode is a respective safety diode which has a higher band gap than its associated laser diode. The safety diode remains nonconductive so long as the associated laser diode is operational. Should the laser diode fail in an open circuit condition, the respective safety diode responds to the open circuit voltage to restore continuity to the serially connected chan of laser diodes.

Abstract: A method of echo cancellation for a signal transmission system in which the size of the step used to adapt filter coefficients is adjusted in accordance with the echo delay and in which stationary signals are avoided by determining when the mean and variance of coefficients obtained from a second order linear predictive coding analysis of successive far end samples exceed preset thresholds.

Abstract: In order to provide an improved heat transfer interface between an solid state device and a heat sink to which it is soldered, one or more “vents” are provided in the interface between the solid state device and the heat sink to prevent the entrapment of gases that could form solder voids. Advantageously, the provision of such vents in the interface surface geometry of the semiconductor may be effected by the use of appropriate masking and etching following the epitaxial regrowth process. Alternatively, the heat sink or a solder preform may be provided with suitable notches. The use of such “die-bond vents” also allows solder, after melting, to be forced under the chip by external gas pressure such that no solder voids are left.

Abstract: A method of shatterproofing a fluorescent lamp having a glass envelope by extruding a polymeric coating over the lamp envelope so that it intimately embraces substantially all of the external contours of the lamp, including its glass envelope and end-ferrules thereby increasing the hoop strength of the glass envelope. The lamp is passed through an air lock into the main lumen of a crosshead which extrudes a cylinder of hot plastic that is radially drawn inward toward the lumen axis by an applied vacuum. A continuous chain of encapsulated lamps emerges from the crosshead that then may be cut apart to reveal individually completely encapsulated lamps.

Abstract: A wafer supporting a semiconductor structure having a material gain function that would preferentially support an Fabry-Perot laser mode at an unwanted wavelength &lgr;2 is provided with a second-order dielectric grating located sufficiently remotely from the high intensity optical field of the quantum well and the waveguide layers to receive just enough transverse mode energy to provide feedback to reduce the gain at &lgr;2 and support oscillation at a desired wavelength &lgr;1. More particularly, by locating the grating in an unpumped area not requiring epitaxial overgrowth and so as to provide a gain discrimination factor &Dgr;g≈0.1 cm−1 at the desired wavelength &lgr;1, the fraction of power lost to transverse mode radiation can be held to about 1% which is sufficient to provide stabilizing feedback without sapping too much energy from the longitudinal beam.