Abstract:
PROBLEM TO BE SOLVED: To provide a technique of a desired sensor apparatus using a total reflection optical system capable of utilizing evanescent waves to obtain high resolution because a sensor apparatus using terahertz waves is difficult to obtain high resolution when using a spatial coupling system.SOLUTION: The sensor apparatus includes: an optical waveguide including an electro-optic crystal 1 for propagating light; a coupler 3 arranged adjacently to the optical waveguide to propagate a terahertz wave generated from the electro-optic crystal by propagating light through the optical waveguide; and a detector 7 for detecting the terahertz wave propagated through the coupler or the light propagated through the optical waveguide. The terahertz wave is totally reflected on a portion of the coupler, which is opposed to a portion adjacent to the optical waveguide, and is propagated through the optical waveguide, and on the total reflection part, the terahertz wave causes to interact with a test object 6 arranged on the total reflection part.
Abstract:
PROBLEM TO BE SOLVED: To overcome any difficulty in attainment of a tunable diode laser absorption spectroscopy (TDLAS).SOLUTION: A multiplexer 16 optically-connected with outputs of two or more diode lasers 12 having selected laser oscillating frequencies is optically-connected with an optical fiber on pitch side. A multiplexed laser beam is transmitted to a pitch optical component 20 associated with a process chamber 22 through the pitch side optical fiber. The pitch optical component 20 is oriented so as to radiate a multiplexed laser output through inside the process chamber. A catch optical component 24 receives the radiated multiplexed laser output. The catch optical component 24 is optically-connected with an optical fiber transmitting the multiplexed laser output to a demultiplexer 28. The demultiplexer 28 demultiplexes a laser beam to optically-connect the selected laser oscillating frequency of the laser beam with a detector 25. This detector has sensitivity to one of the selected laser oscillating frequencies.
Abstract:
PROBLEM TO BE SOLVED: To provide a system for monitoring and/or controlling an emission level of nitrogen oxides and a reducing agent from a stream of combustion exhaust gas of an internal combustion engine. SOLUTION: The internal combustion engine (116) includes an SCR (selective catalytic reduction) unit arranged in the stream of the combustion exhaust gas between an upstream conduit (124) and a downstream conduit (126). The SCR unit includes a catalyst configured to catalytically reduce the nitrogen oxides contained in the combustion exhaust gas to nitrogen atoms under the presence of the reducing agent and oxygen. Moreover, the internal combustion engine (116) further includes a reducing agent injection device (212). Under such conditions, the system includes a laser absorption spectroscopy unit (300) arranged in the downstream conduit (126) and configured to measure at least the concentration level of the nitrogen oxides and the reducing agent in the stream of the combustion exhaust gas, and a control unit (216). COPYRIGHT: (C)2011,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To provide an inexpensive gas sensor of high measuring precision and simple structure, and to provide a method for manufacturing the gas sensor. SOLUTION: The gas sensor has a light source 4 introduced into a base 8, a detector 6 for detecting an intensity of the light source 4, and a reflector 2a related to the light source 4. The problem of providing the gas sensor of high measuring precision is solved by a means 20 for fixing immovably a lamp body 10 of the light source 4 without play. The problem of providing the manufacturing method for the inexpensive gas sensor is solved by introducing the light source 4 under the condition where a liquid solvent 28 is interposed between the light source 4 and the base 8, and by solidifying the liquid solvent 28 for forming the means 20 that is a solid finally, so as to fix immovably the lamp body 10 of the light source 4 in the means 20 of the solid, without generating the play. COPYRIGHT: (C)2007,JPO&INPIT