Abstract:
A method for characterizing fluorescent molecules or other particles in samples comprising the steps of: a) monitoring fluctuating intensity of fluorescence emitted by the molecules or other particles in at least one measurement volume of a non-uniform spatial brightness profile by measuring numbers of photon counts in primary time intervals by a single or more photon detectors, b) determining at least one distribution of numbers of photon counts, P(n), from the measured numbers of photon counts, c) determining physical quantities characteristic to said particles by fitting the distribution of numbers of photon counts P(n), wherein the fitting procedure involves calculation of a theoretical distribution function of the number of photon counts P(n) through its generating function, defined as (I).
Abstract:
A method of in situ analysis of a biological sample comprising the steps of (a) staining the biological sample with N stains of which a first stain is selected from the group consisting of a first immunohistochemical stain, a first histological stain and a first DNA ploidy stain, and a second stain is selected from the group consisting of a second immunohistochemical stain, a second histological stain and a second DNA ploidy stain, with provisions that N is an integer greater than three and further that (i) if the first stain is the first immunohistochemical stain then the second stain is either the second histological stain or the second DNA ploidy stain; (ii) if the first stain is the first histological stain then the second stain is either the second immunohistochemical stain or the second DNA ploidy stain; whereas (iii) if the first stain is the first DNA ploidy stain then the second stain is either the second immunohistochemical stain or the second histological stain; and (b) using a spectral data collection device for collecting spectral data from the biological sample, the spectral data collection device and the N stains are selected such that a spectral component associated with each of the N stains is collectable.
Abstract:
Es wird ein Faserdetektor zur Detektion des Streulichtes oder des Fluoreszenzlichtes einer flüssigen Suspension beschrieben, der
eine einmodige oder mehrmodige optische Faser mit Gradientenindexlinse am Faserausgang zur Erzeugung paralleler Lichtstrahlen, eine Sammellinse oder ein Sammellinsensystem zur Fokussierung der parallelen Lichstrahlen auf einem Punkt innerhalb der Suspension, eine weitere einmodige oder mehrmodige, mit Gradientenindexlinse am Fasereingang versehene und mit einem Photodetektor verbundene optische Faser zur Detektion des zurückgestreuten und durch dieselbe Sammellinse oder dasselbe Sammellinsensystem parallelisierten Lichtes enthält.
Abstract:
A differential spectrometry system detects very narrow-band spectral features, while providing much higher optical transmittance and signal-to-noise ratios than prior optical-filter-based spectrometer systems. A plurality of light detectors (10a, 10b) detect light that falls within respective wide wavebands. The wide wavebands have overlapping and non-overlapping portions, one of which is the desired narrow waveband. The detector outputs are operated upon to produce an output signal (22) which includes substantially only the desired narrow waveband. In the preferred embodiment, the light detectors (10a, 10b) are implemented with a pair of optical detectors (30a, 30b) and respective optical interference filters (24a, 24b). The filters have substantially identical cut-off wavelengths (λ 2 ) and cut-on wavelengths that are shifted by Δλ with respect to each other (λ 1 and (λ 1 +Δλ), respectively). The detector outputs are differenced with an operational amplifier (33), so that detector signals resulting from spectral features common to both detectors (30a, 30b) are canceled. The remaining signal (36) varies according to the amount of light that falls between wavelength boundaries [λ 1 and (λ 1 +Δλ)]. A preferred method of fabricating the optical interference filters (24a, 24b) is also provided.
Abstract:
In dem Verfahren und der Vorrichtung zur Bestimmung von Diffusionsparametern, Konzentration, Größe oder Strömungsverhalten von Partikeln in einer Probe, werden Anregungslicht einer Lichtquelle in die Probe geleitet, Raman-Streulicht aus einem Beobachtungsvolumen der Probe aufgefangen und einem Spektrographen zugeführt wird, wo es in Spektrallinien zerlegt wird, wobei die Intensität mindestens einer Spektrallinie mindestens 10 mal pro Sekunde mit jeweils einem Photodetektor gemessen wird, und aus den gemessenen Intensitätswerten für die jeweilige Spektrallinie durch eine Fluktuationsanalyse, vorzugsweise eine Autokorrelation oder eine Frequenzanalyse, Diffusionsparameter, Konzentration, Größe oder Strömungsverhalten der Partikel, denen die jeweilige Spektrallinie zuzuordnen ist, berechnet. Bei diesem Verfahren können auch Signale verschiedener Spektrallinien oder -banden oder Signale von Raman-Streulicht, quasielastisch gestreutem Licht und Fluoreszenzlicht miteinander korreliert werden.