Abstract:
A device for measuring the fluorescence of a medium having a radiation source, an emission-receiving element and an optical imaging element arranged on the sensor side of the optical imaging element, and a scattering-receiving element arranged on the sensor side of the optical imaging element and in which the radiation source, the imaging element and the emission-receiving element are aligned and configured relative to one another so that the medium present on the medium side of the imaging element can be illuminated by radiation from the radiation source, and the emission intensity of the medium radiation emitted by the medium based on fluorescence can be detected with the emission-receiving element. To provide a device for measuring the fluorescence of a medium which has an increased reliability in measuring the fluorescence, temperature compensation is performed relative to the temperature of the medium and/or at least one of the receiving elements.
Abstract:
A gas detector (10) that is arranged to sense the concentration levels of target gases oxygen, methane, carbon monox-ide, and hydrogen sulphide, within a gas sample from an environment surrounding the detector. The gas detector (10) comprises laser sources (12a-12d) that are arranged to transmit radiation through the gas sample at four target wavelengths that correspond approximately to the optimum absorption wavelengths of each of the target gases and an optical detector (16) that is arranged to sense the intensity of the radiation transmitted through the gas sample at each of the target wavelengths. A control system (22) generates representative concentration level information for the target gases based on the level of absorption of the radiation transmitted.
Abstract:
An optical system includes a sample substrate having a surface, the surface defining a 2-dimensional sample plane. The system includes an excitation source configured to provide excitation light to the sample substrate. The system further includes an optical detector configured to receive emission light from the sample substrate and generate detection data. The system also includes a scan head configured at least (i) to direct the excitation light towards the sample substrate, (ii) to receive emission light from the sample substrate and direct the emission light towards the optical detector, and (iii) for scanning relative to the sample substrate. The system includes at least one actuator configured to scan the scan head relative to the sample substrate, the at least one actuator being configured to provide at least one of (1) a relative linear motion and a relative angular motion about a rotational axis generally perpendicular to the sample plane and (2) two relative angular motions about two respectively different rotational axes generally perpendicular to the sample plane.
Abstract:
A body fluid constituents measurement device, which performs measurement under a setting where light intensity of the light-emitting element is suitably stabilized, is provided. The present invention is a body fluid constituents measurement device which comprises: a light-emitting element that emits light onto a test paper onto which body fluid is spotted, a light receiving element which receives reflected light of the light emitted by said light-emitting element, a temperature measurement unit which measures the ambient temperature in the vicinity of said light-emitting element, a determination unit which determines conditions of light emission based on said temperature measured at said temperature measurement unit in order to stabilize light intensity of said light-emitting element, and a driving control unit which controls driving of said light-emitting element based on the conditions of light emission; and is characterized in that it starts measurement of body fluid constituents after the light intensity of light emitted by said light-emitting element has been stabilized.
Abstract:
Apparatus for remote laser-based detection of a analyte in a remote target region; comprising a reference container for housing a reference substance identical with the analyte; a laser unit which constituted to emit a laser beam of a tuneable wavelength towards the target region to be analysed and along a reference path which passes through the reference container for detecting the reference substance; a laser control means constituted to control wavelength of the laser beam during detection periods such that the laser wavelength is changed to allow detection of an optical absorption profile of the analyte during detection periods; an analytical detection unit which detects light from the target region and generates analytical signals during the detection periods, a reference detection unit which detects laser light passed through the reference container and generates reference signals during the detection periods; and an analysing means constituted to analyse the similarity of the analytical and reference signals or of one or more calculated functions respectively calculated from the analytical and reference signals for determining the concentration of the analyte in the target region.
Abstract:
Methods and apparatus for controlling a brazing process. In one embodiment, a method includes receiving a signal from a tunable diode laser indicating a measured concentration of a gas present in an atmosphere in which the brazing process is performed. Responsive to the received signal, a control signal is issued to adjust at least one brazing process control setting affecting a change in subsequently measured concentrations of the gas present in the atmosphere.
Abstract:
The invention is a method of measuring oxygen concentration in a package having an oxygen sensitive product disposed therein. The method includes exposing a luminescent compound that is disposed in an interior of the package to light having a wavelength that is absorbed by the luminescent compound so that the luminescent compound is promoted into an excited state. When the exposure of the light is terminated, the excited luminescent compound emits light that is detectable by a detector positioned outside of the package. The intensity of the emitted light is inversely proportional to the oxygen concentration and is used in conjunction with mathematical function that describes the luminescent intensity of the luminescent compound as a function of oxygen concentration and temperature to calculate the oxygen concentration. The method may be used to verify and track the oxygen concentration of a package as it moves through a distribution system.
Abstract:
The invention concerns a gas analyzer comprising: a measuring volume (2), a radiation source (1) for providing a beam to pass said measuring volume; a heat sink (16) for said radiation source; at least one thermal detector (3) having a hot junction within a support structure and receiving the radiation and a cold junction for reference within the same support structure and protected from said radiation; at least one optical bandpass filter (9) between said hot junction and said radiation source; and a thermal mass (11), which is formed of a material having high thermal conductance. The thermal mass has a cavity with a bottom step (34) and a rim (32), and a first length therebetween. The support structure has a frontal edge (35) and a base plate lip (33), and a second length therebetween. There is a radial gap between the thermal mass and the support structure. Press means urge said support structure in the cavity, whereupon a more efficient thermal contact is either between said frontal edge and said bottom step, or between said base plate lip and said rim. A first thermal barrier (17) is between the heat sink and the thermal mass, and a second thermal barrier (22) surrounds the thermal mass. A shield (19) formed of a material having high thermal conductance covers said second thermal barrier and is in thermal contact with said heat sink.
Abstract:
A gas sensor, whose chamber uses filters and choppers in either a semicircular geometry or annular geometry, and incorporates separate infrared radiation filters and optical choppers. This configuration facilitates the use of a single infrared radiation source and a single detector for infrared measurements at two wavelengths, such that measurement errors may be compensated.
Abstract:
A fourth embodiment of the present invention is a method of generating a temperature compensated absorbance spectrum. The method includes the steps of: a. providing a sample spectrum and an estimated temperature of a backdrop object; b. from a set of known temperature spectra related to a known background temperature, selecting at least two known temperature spectra representing a background temperature above and below the estimated temperature; c. comparing the sample spectrum to the known temperature spectra in order to determine a sample background spectrum; and d. calculating an absorbance spectrum from the sample spectrum and the background spectrum.