Abstract:
The invention provides on the one hand a method for measuring the spectrum of a material, wherein a sample (10) of the material to be tested is irradiated with a radiation of required wavelengths and the spectrum signals produced by an intensity measuring unit (34) as a result of the radiation reflected or transmitted by the sample (10) are measured. According to the present invention, a zero level signal produced by the intensity measuring unit (34) in an unradiated condition is measured and the measured zero level value is stored, then one or more spectrum signal measurements are performed at at least one wavelength and the measured one or more spectrum values are stored, then the zero level signal produced by the intensity measuring unit (34) is measured again in an unradiated condition and its value is stored, then preferably said one or more spectrum signal measurements at at least one wavelength prescribed and said storage of the measured values as well as said zero level signal measurement and said storage of the measured value are repeated as many times as required, and finally the stored spectrum values are modified by correction values generated on the basis of the stored zero level values. On the other hand the invention is an apparatus for measuring the spectrum of a material comprising a controllable monochromator (1) emitting a radiation of a required wavelength onto a sample (10) of the material to be tested, an intensity measuring unit (34) provided with a sensor (11) sensitive to the radiation reflected or transmitted by the sample (10), a data processing unit (14) connected to the intensity measuring unit (34) via an analog-to-digital converter (13), and a control unit controlling the analog-to-digital converter (13) synchronously with the monochromator (1) while irradiating the sample (10) with the radiation of the required wavelength. According to the invention the control unit comprises means (17, 7, 27, 29, 21,19) to provide at least one start signal onto a control input (31) of the analog-to-digital converter (13) prior to and/or after the period of irradiating the sample (10) with the radiation of the required wavelength (Figure 1).
Abstract:
A micro-Raman device includes a first laser light source, a second laser light source, a first holder, a second holder, a first ND filter, and a second ND filter. The first laser light source and the second laser light source generate first laser light of a first wavelength and second laser light of a second wavelength, respectively. The second wavelength is different from the first wavelength. The first laser light and the second laser light proceed in a second direction orthogonal to a first direction while being separated from each other in the first direction. The first holder and the second holder are arranged overlapping each other in the second direction.
Abstract:
The invention relates to a method and to a device for calibrating an optical resonator. The method comprises the following steps: generating light pulses of a known pulse frequency by means of a light-pulse generation unit; coupling the light pulses into the resonator (20); detecting light exiting the resonator (20) by means of a detection apparatus in order to generate a detection signal, wherein the detection apparatus is designed to generate the detection signal by means of a modulator as a signal modulated with a modulation frequency, wherein the modulation frequency is substantially equal to the pulse frequency of the generated light pulses or wherein the modulation frequency is substantially an integer multiple of the pulse frequency of the generated light pulses or wherein the pulse frequency of the generated light pulses is substantially an integer multiple of the modulation frequency; and calibrating the optical resonator (20) on the basis of the detection signal. The invention further relates to a use of the device according to the invention, to a use of a switchable detector or of an optical modulator, and to a computer program product.
Abstract:
The present invention relates to an apparatus for detecting photons according to an atmospheric condition, using a function of adjusting light quantity that can significantly improve reliability of an atmospheric condition analysis result by minimizing noise in a spectrum by maintaining the quantity of incident light uniform within a predetermined range regardless of atmospheric conditions and changes, and to a method of adjusting light quantity. The apparatus for detecting photons in accordance with atmospheric conditions using a function of adjusting light quantity includes: an apparatus case having a light inlet; a light quantity adjuster disposed under the light inlet and adjusting quantity of incident light such that a predetermined quantity of light travels inside; and a controller controlling operation of the light quantity adjuster in accordance with intensity of light detected by the light quantity adjuster.
Abstract:
An optical imaging system and method including a movable pixelated filter array, a shutter mechanism to which the pixelated filter array is attached, and a controller configured to implement a data reduction algorithm. The shutter mechanism is configured to move the pixelated filter array into and out of the optical path, and the data reduction algorithm allows the controller to account for axial and/or lateral misalignment of the filter array relative to the imaging detector array or its conjugate. In certain examples, the controller is further configured to use the data reduction algorithms also to perform wavefront sensing, for example to estimate wavefront error.
Abstract:
- Le dispositif (1) comporte au moins une cavité de Fabry-Pérot (3) présentant un écartement (E) réglable, dont une valeur d'écartement dite nominale permet un passage à travers ladite cavité de Fabry-Pérot (3) pour un rayonnement laser (4) de fréquence correspondante, des moyens d'actionnement (5A) commandables, de type piézo-électrique, aptes à faire varier ledit écartement (E), dans un domaine de valeurs d'écartement comprenant ladite valeur nominale, et une unité de commande (6) pour commander lesdits moyens d'actionnement (5A) de sorte qu'ils fassent varier l'écartement (E) selon une fonction périodique au cours du temps.
Abstract:
Method and apparatus for detecting, by absorption spectroscopy, an isotopic ratio of a sample, by passing first and second laser beams of different frequencies through the sample. Two IR absorption cells are used, a first containing a reference gas of known isotopic ratio and the second containing a sample of unknown isotopic ratio. An interlacer or reflective chopper may be used so that as the laser frequencies are scanned the absorption of the sample cell and the reference cell are detected alternately. This ensures that the apparatus is continuously calibrated and rejects the baseline noise when phase sensitive detection is used.
Abstract:
Es wird eine Vorrichtung zur wahlweisen Messung von insbesondere Lumineszenz- und/oder Fluoreszenzstrahlung aus mindestens einem Probenbehälter (11) mittels mindestens einer Lichtquelle (50) im Anregungslichtpfad (AF) für Fluoreszenzmessungen und mindestens einem Detektor (40) mit einem Wellenlängenselektor im Emissionslichtpfad (EF) beschrieben. Um mit einem gemeinsamen Emissionslichtpfad sowohl für Fluoreszenz als auch für Lumineszenz die gleiche Empfindlichkeit erreichen zu können, ist der Emissionslichtpfad (EF) zwischen dem zumindest einen Probenbehälter (11) und dem Wellenlängenselektor durch mindestens ein erstes, eine Reflexionskammer (R) umschließendes Reflektorelement (20) geführt, das zumindest einen Teil des vom Probenbehälter (11) emittierten Lichts gerichtet auf den Wellenlängenselektor wirft, wobei der Anregungslichtpfad (AF) in der Reflexionskammer (R) bis oberhalb des Probenbehälters (11) geführt ist.