摘要:
An apparatus includes a member including a ferromagnetic material, an inductance-capacitance resonant circuit, a substrate disposed relative to the member, and a plurality of radiation sources. The member includes a post disposed at its center and a surface extending to an outer wall. The member defines a gap between the post and the outer wall. The inductance-capacitance resonant circuit is configured to resonate at a measurement frequency. The circuit includes an inductor disposed relative to the post. The substrate is disposed relative to the member. The substrate is electromagnetically coupled to the inductor. The plurality of radiation sources is disposed radially outward from and circumferentially around the post of the member. The apparatus can be used to simultaneously measure conductance (inverse sheet resistance), steady state photoconductance, true steady state minority carrier lifetime, photoconductance build-up and photoconductance decay lifetime.
摘要:
A substrate is electromagnetically coupled into an inductance-capacitance resonant circuit formed from (i) a member comprising a ferromagnetic material, (ii) an inductor and (iii) the substrate. The substrate is illuminated for a first time period X to cause photoconduction in the substrate. Decay in conductivity of the substrate is monitored for a second time period Y. The ratio of X to Y is greater than 1:10. Bulk lifetime of the substrate is determined from the decay.
摘要:
An optical sensor apparatus includes an optically transmissive structure having planar first, second, and third faces, two or more light sources located outside the structure adjacent the first face, and a photodetector array located outside the prism adjacent the first face. The structure, light sources, and photodetector array are configured such that light from the light sources that is totally internally reflected at an optical interface between the prism and a sample outside the structure proximate the second face is reflected at the third face and incident on a portion of the photodetector array that depends on a refractive index of the sample. The light sources are positioned with respect to the structure and photodetector array such that the totally internally reflected light from each light source corresponds to a different range of refractive index of the sample and maps to a corresponding portion of the photodetector array.
摘要:
An apparatus utilizes miniaturized surface plasmon resonance (SPR) and ion-selective self-assembled monolayer (SAM) and hydrogel chemistry to measure metal ion concentrations in liquids. The SPR optical system is packaged in a compact and cost-effective form factor. An electronic circuit drives the optical system. The SPR system utilizes an optical window that is coated with the SAM layer or hydrogel material. The SAM layer and hydrogel materials are highly selective to a specific metal ion of interest. The miniaturized SPR sensor is situated in an optical-fluidic cell or an optical-fluidic manifold with the SAM layer or hydrogel material in contact with the liquid. Metal ions selectively attach to the SAM layer or hydrogel material, thereby affecting the SPR signal. Changes in the SPR signal are used to accurately determine the metal ion concentration in the liquid. The liquids may be either static or dynamic.
摘要:
An apparatus utilizes optical reflectivity (REF) to measure concentrations in liquids. The REF optical system is packaged in a compact and cost-effective form factor. An electronic circuit drives the optical system. The miniaturized REF sensor is situated in an optical-fluidic cell or an optical-fluidic manifold with an optical window in contact with the liquid. Changes in a total internal reflection (TIR) signal are sensitive to temperature and concentration of the liquid. These changes in the TIR signal are used to accurately determine the concentration in the liquid. The liquids may be either static or dynamic.
摘要:
An apparatus utilizes optical reflectivity (REF) to measure concentrations in liquids. The REF optical system is packaged in a compact and cost-effective form factor. An electronic circuit drives the optical system. The miniaturized REF sensor is situated in an optical-fluidic cell or an optical-fluidic manifold with an optical window in contact with the liquid. Changes in a total internal reflection (TIR) signal are sensitive to temperature and concentration of the liquid. These changes in the TIR signal are used to accurately determine the concentration in the liquid. The liquids may be either static or dynamic.
摘要:
An optical sensor apparatus includes an optically transmissive structure having planar first, second, and third faces, two or more light sources located outside the structure adjacent the first face, and a photodetector array located outside the prism adjacent the first face. The structure, light sources, and photodetector array are configured such that light from the light sources that is totally internally reflected at an optical interface between the prism and a sample outside the structure proximate the second face is reflected at the third face and incident on a portion of the photodetector array that depends on a refractive index of the sample. The light sources are positioned with respect to the structure and photodetector array such that the totally internally reflected light from each light source corresponds to a different range of refractive index of the sample and maps to a corresponding portion of the photodetector array.
摘要:
An apparatus utilizes optical reflectivity (REF) to measure concentrations in liquids. The REF optical system is packaged in a compact and cost-effective form factor. An electronic circuit drives the optical system. The miniaturized REF sensor is situated in an optical-fluidic cell or an optical-fluidic manifold with an optical window in contact with the liquid. Changes in a total internal reflection (TIR) signal are sensitive to temperature and concentration of the liquid. These changes in the TIR signal are used to accurately determine the concentration in the liquid. The liquids may be either static or dynamic.
摘要:
An apparatus utilizes optical reflectivity (REF) to measure concentrations in liquids. The REF optical system is packaged in a compact and cost-effective form factor. An electronic circuit drives the optical system. The miniaturized REF sensor is situated in an optical-fluidic cell or an optical-fluidic manifold with an optical window in contact with the liquid. Changes in a total internal reflection (TIR) signal are sensitive to temperature and concentration of the liquid. These changes in the TIR signal are used to accurately determine the concentration in the liquid. The liquids may be either static or dynamic.