A biological component measurement apparatus includes an optical medium, a high thermal conductive film, an excitation light source, a probe light source, and a light position detector. The high thermal conductive film is higher in thermal conductivity than the optical medium, and is provided on a sample placement surface of the optical medium. The high thermal conductive film spreads heat generated from the sample irradiated with excitation light more in a first direction than in a second direction. The first direction is a traveling direction of probe light in plan view of the sample placement surface. The second direction is a direction orthogonal to the first direction in plan view of the sample placement surface.

The present disclosure describes a differential refractometer for gradient chromatography. In an exemplary embodiment, the differential refractometer includes a solvent delay volume, an eluent flow meter coupled to an eluent inlet of a sample cell, a solvent flow regulator coupled to an outlet of the solvent delay volume and coupled to a solvent inlet of a reference cell, an instrument controller configured to receive the eluent flow rate from the eluent flow meter, configured to receive the solvent flow rate from the solvent flow regulator, configured to receive a flow rate ratio from a flow rate ratio data source, wherein the flow rate ratio indicates a ratio of the eluent flow rate to the solvent flow rate, and an optical bench configured to measure a difference between a refractive index of the eluent present in the sample cell and a refractive index of the solvent present in the reference cell.

A photodiode includes semiconductor layers and a gate insulating layer provided on a buried insulating layer formed on a substrate and has a diffraction grating portion in which a plurality of groove portions are formed in a two-dimensional lattice shape, on the gate insulating layer. Measurement light is guided by an optical system including a photoelastic modulator and is incident on the photodiode. The measurement light is emitted from the light source device in a state of being linearly polarized light having a predetermined wavelength and is converted at a predetermined frequency by the optical system such that states in which the measurement light becomes linearly polarized light beams of two orthogonal directions are repeated. In addition, electric signals from the photodiode in the state in which the measurement light becomes the linearly polarized light beams of the two orthogonal directions are lock-in detected.

An apparatus for detecting one or more properties of a downhole fluid includes a housing. The apparatus also includes a location-sensitive optical detector, arranged within a chamber formed by the housing. The apparatus further includes a light source, arranged within the chamber. The apparatus also includes a lens, positioned at an end of the housing, the lens preferably having a flat side and a curved side, the flat side positioned proximate the chamber to position the flat side closer to the light source than the curved side. The apparatus further includes a mirror, arranged outside the housing.

A method for adjusting a focus of an optical system includes focusing measurement light in a sample space using an optical arrangement. The measurement light is transmitted on a sample side of the optical arrangement through at least one optical medium. The measurement light reflected by a reflector and transmitted through a further optical arrangement is detected using a detector arrangement. A working distance between the optical arrangement and the reflector is ascertained based on the measurement light detected by the detector, wherein a focus of the measurement light lies on the reflector for the working distance.

A digital microfluidic (DMF) system, DMF cartridge, and method including integrated refractive index (RI) sensing is disclosed. The digital microfluidic DMF system and DMF cartridge may include, for example, a RI sensor (or sensor surface) directly in the droplet operations gap of a DMF cartridge. The digital microfluidic DMF system may include, for example, the DMF cartridge, one or more illumination sources, one or more optical measurement devices, and a controller. Additionally, a method of using the DMF system and DMF cartridge that includes integrated RI sensing is provided.

A system for sensing analyte in at least partly translucent material, including one or more radiation sources configured for successively providing radiation at a first and a second wavelength, respectively, two or more waveguides for simultaneously transmitting the radiation at each wavelength provided by the radiation source, a first waveguide being a reference waveguide and a second being a sensing waveguide; and measuring means for measuring a phase difference between the radiation waves from the reference waveguide and the measuring waveguide, resp. The present method can be used for measuring contaminants such as Fe, Sn, and/or Pb in oil related products, such as carburant or lubricant.

Disclosed are systems and methods of label-free detecting cellular physiological activities involving monitoring local refractive index changes associated with cellular physiological activities using a single ultracompact light emitting diode (LED) chip serving as a refractometer.

An apparatus includes a measurement chamber configured to retain one or more sample substances. The apparatus includes an entrance window mounted on a side of the measurement chamber. The apparatus includes a light source configured to generate an incident light beam. The apparatus includes a Raman sensor configured to collect inelastically scattered light from the chamber, and measure an intensity of a Raman peak of a first substance from the one or more sample substances based on the collected inelastically scattered light. The apparatus further includes a processor configured to (i) calculate a concentration of the first substance based on at least the measured intensity of the Raman peak of the first substance, (ii) determine the end point of a wafer cleaning process based on a calculated concentration of the first substance, and (iii) terminate the wafer cleaning process based on the determined end point.

An instrument incorporating a refractometer for measuring parameters of a fluid such as a metalworking fluid, avoids impairment of measurement accuracy due to contact of entrained air and oil with a refractometer window by temporarily interrupting the flow of the fluid through a refractometer chamber and orienting the window so that air and oil will readily separate from the window during the interruption of flow. Continued flow of metalworking flow while refractive index measurements are taken can be achieved by the use of by-pass valving arrangements.