A fluorescence detection apparatus for analyzing samples located in a plurality of wells in a thermal cycler and methods of use are provided. In one embodiment, the apparatus includes a support structure attachable to the thermal cycler and a detection module movably mountable on the support structure. The detection module includes one or more channels, each having an excitation light generator and an emission light detector both disposed within the detection module. When the support structure is attached to the thermal cycler and the detection module is mounted on the support structure, the detection module is movable so as to be positioned in optical communication with different ones of the plurality of wells. The detection module is removable from the support structure to allow easy replacement.

A method for correcting a fluorescence image of an object, for example a biological tissue that can include fluorescent agents. The distance between a fluorescence probe generating the fluorescence image and the object examined is measured. This distance is used to apply a correction function to the fluorescence image. The method may find application in perioperative fluorescence imaging for diagnosis and monitoring of evolution of pathologies, for example of cancers.

A System and method for self-checking a fluorometer for failure or deteriorated performance includes fluorescent reference standards mounted on a support to move with respect to one or more fixed fluorometers. The intensity of the fluorescent emission of the fluorescent reference standard is initially measured with the fluorometer, and, after a prescribed interval of usage of the fluorometer, a test measurement of the intensity of the fluorescent emission of the fluorescent standard is taken with the fluorometer. The test measurement is compared to the initial measurement, and failure or deteriorated performance of the fluorometer is determined based on a deviation of the test measurement from the initial measurement.

A method of imaging a sample comprises serially illuminating the sample by a plurality of light beams, each having a different central wavelength. The method also comprises: serially acquiring from the sample image data by an imager, wherein the image data represent optical signals received from the sample responsively to the plurality of light beams. The method also comprises shifting a field-of-view of the sample relative to the imager, repeating the serial illumination and the image data acquisitions for the shifted field-of-view, and generating a spectral image of the sample using image data acquired by the imager at a plurality of field-of-views for each of the plurality of light beams.

In a standard process for determining an unknown sample, fluorescent substances are determined from respective fluorescence characteristics and model coefficients are calculated from spectrum ranges of the fluorescence characteristics of the determined fluorescent substances. An unknown sample is measured after reading of the model coefficients, whereby a target value of the unknown sample is obtained.

In order to reduce a variation in the light amount of light detected in every reference measurement cycle in an absorption spectrometer 1, it is adapted to tilt at least one surface selected from among incident surfaces and emitting surfaces of all translucent members constituting a reference cell with respect to the light axis of light traveling along a light path.

An isotope ratio of a continuous sample is measured in an isotope ratio spectrometer. At least one sample isotope ratio is measured over a measurement time period t.sup.n.sub.s, (n1) and a sample concentration c.sup.n.sub.s is measured over at least a part of the measurement time period t.sup.n.sub.s. A reference gas concentration c.sup.n.sub.ref for the spectrometer is selected for reference to the sample measured during the measurement time period t.sup.n.sub.s, on the basis of the measured sample concentration c.sup.n.sub.ref. An isotope ratio of the reference gas is measured at the selected reference gas concentration c.sup.n.sub.ref in the spectrometer. The at least one isotope ratio of the sample measured during the measurement time period t.sup.n.sub.s is calibrated using the measured isotope ratio of the reference gas at the corresponding reference gas concentration c.sup.n.sub.ref and a plurality of calibrated isotope ratios and a plurality of sample gas concentration measurements are determined, each being for a different time.

This relates to systems and methods for measuring a concentration and type of substance in a sample at a sampling interface. The systems can include a light source, optics, one or more modulators, a reference, a detector, and a controller. The systems and methods disclosed can be capable of accounting for drift originating from the light source, one or more optics, and the detector by sharing one or more components between different measurement light paths. Additionally, the systems can be capable of differentiating between different types of drift and eliminating erroneous measurements due to stray light with the placement of one or more modulators between the light source and the sample or reference. Furthermore, the systems can be capable of detecting the substance along various locations and depths within the sample by mapping a detector pixel and a microoptics to the location and depth in the sample.

A lighting device that emits illumination light from two or more angular directions onto a sample surface to be measured, an imaging optical lens, and a monochrome two-dimensional image sensor are provided. This configuration provides a method and an apparatus that take a two-dimensional image of the sample surface to be measured at each measurement wavelength and accurately measure multi-angle and spectral information on each of all pixels in the two-dimensional image in a short time. In particular, a multi-angle spectral imaging measurement method and apparatus that have improved accuracy and usefulness are provided.

The nitrate-nitrogen concentration in soil is estimated based on the nitrate-nitrogen 200 nm absorption peak. In one embodiment, a device measures the attenuation spectrum of a soil-extractor mixture over a wavelength range that includes wavelengths in the vicinity of the 200 nm absorption peak (the spectral operating range) and then determines the nitrate-nitrogen concentration based on the attenuation spectrum.