Abstract:
A first contact (310) surface of a semiconductor laser chip (302) is formed to a surface roughness selected to have a maximum peak to valley height that is substantially smaller than a diffusion barrier layer thickness. A diffusion barrier layer that includes a non-metallic, electrically-conducting compound and that has the barrier layer thickness is applied to the first contact surface, and the semiconductor laser chip is soldered to a carrier mounting (304) along the first contact surface using a solder composition (306) by heating the soldering composition to less than a threshold temperature at which dissolution of the barrier layer into the soldering composition occurs. Thereby the diffusion barrier remains contiguous. The non-metallic, electrically conducting compound may comprise at least one of titanium nitride, titanium oxy-nitride, tungsten nitride, cerium oxide and cerium gadolinium oxy-nitride
Abstract:
Thermally controlled enclosures that can be used with gas analyzers are described. The enclosures incorporate one or more phase changing materials that buffer ambient and internal heat loads to reduce the power consumption demand of mechanical or electronic heating apparatus. Maintenance of gas analyzer equipment at a consistent temperature can be important to achieving stable and reproducible results. Related systems, apparatus, methods, and/or articles are also described.
Abstract:
Scrubber media for reactive gases, that can include but are not necessarily limited to hydrogen chloride (HCl), hydrogen sulfide (H2S), hydrogen fluoride (HF), and ammonia (NH3), can include reactive particles, potentially as small as nano-scale, that can optionally be suspended on macro-scale carrier particles. Reactive gases can be converted to non-volatile compounds by being passed through a bed of such scrubber media. Such scrubber media can be used to remove reactive gases from gas mixtures. Potential applications include differential absorption spectroscopy, air pollutant emission controls, and the like. Methods of preparing scrubber media are also described.
Abstract:
An apparatus for detecting a concentration of a trace target gas in a sample gas comprises a light source (110), for example a tunable diode laser, for emitting light at a wavelength corresponding to an absorption line of the target gas and means (105) operatively connected to said light source for modulating the wavelength of the emitted light, a detector (125) positioned to detect the intensity of light emitted from the light source that has passed through the sample gas at a multiple of the modulation frequency of the light source, for example second harmonic detection, a pressure sensor (120) for detecting the pressure of the sample gas, and a control unit (135) coupled to the detector, the pressure sensor, and the light source, said control unit being arranged to adjust the modulation amplitude' of the light source based on the detected pressure.
Abstract:
A technique is disclosed for the detection of water vapor in a natural gas background. The system includes a light source (519) emitting light approximately within wavelength ranges such as 920- 960 nm, 1.877 - 1.901, or 2.711 - 2.786 . The light source emits light through a sample of natural gas that is detected by a detector (523). In one embodiment, the light source is a tunable diode laser and the moisture level is determined by harmonic spectroscopy. In other embodiments, a VCSEL, a color center laser, or a quantum cascade laser is utilized.
Abstract:
A light source module may include a base with a support feature protruding from a surface of the base and securing a light source to direct radiation away from the surface. A lens cells may be attached proximate to the surface, optionally by being secured within a sleeve that is attached at one end to the surface. A multi-conductor part may include electrical conductors and a base temperature sensor that contacts the base. The base temperature sensor may be electrically connected to at least one of the plurality of conductive elements and further connected to an optical ignition safety protection system configured to interrupt current to the light source if the base temperature sensor indicates that a temperature of the light source is outside of a safe range.
Abstract:
A first contact surface of a semiconductor laser chip can be formed to a target surface roughness selected to have a maximum peak to valley height that is substantially smaller than a barrier layer thickness. A barrier layer that includes a non-metallic, electrically-conducting compound and that has the barrier layer thickness can be applied to the first contact surface, and the semiconductor laser chip can be soldered to a carrier mounting along the first contact surface using a solder composition by heating the soldering composition to less than a threshold temperature at which dissolution of the barrier layer into the soldering composition occurs. Related systems, methods, articles of manufacture, and the like are also described.
Abstract:
An optical head assembly for use in a spectrometer is provided that is configured to characterize one or more constituents within a sample gas. The assembly includes a thermoelectric cooler (TEC) having a cold side on one end and a hot side on an opposite end, a cold plate in thermal communication with the cold side of the TEC, a hot block in thermal communication with the hot side of the TEC, a light source in thermal communication with the cold plate such that a change in temperature of the TEC causes one or more properties of the light source (e.g., wavelength, etc.) to change, and an optical element in thermal communication with the cold plate positioned to collimate light emitted by the light source through the sample gas (such that properties of the optical element vary based on a change in temperature of the TEC).
Abstract:
At least one light source is configured to emit at least one beam into a sample volume of an absorbing medium. In addition, at least one detector is positioned to detect at least a portion of the beam emitted by the at least one light source. Further, at least one beam modification element is positioned between the at least one detector and the at least one light source to selectively change at least one of (i) a power intensity of, or (ii) a shape of the beam emitted by the at least one light source as detected by the at least one detector. A control circuit is coupled to the beam modification element. Related apparatus methods, articles of manufacture, systems, and the like are described.
Abstract:
A first contact surface of a semiconductor laser chip can be formed to a target surface roughness selected to have a maximum peak to valley height that is substantially smaller than a barrier layer thickness. A barrier layer that includes a non-metallic, electrically-conducting compound and that has the barrier layer thickness can be applied to the first contact surface, and the semiconductor laser chip can be soldered to a carrier mounting along the first contact surface using a solder composition by heating the soldering composition to less than a threshold temperature at which dissolution of the barrier layer into the soldering composition occurs. Related systems, methods, articles of manufacture, and the like are also described.