Abstract:
Un accessoire permet de convertir un microscope conventionnel en un microspectrofluorimètre. L'accessoire comprend un disque de filtrage (52) ayant des filtres passe-bande (54, 56) séparés par des segments opaques (58, 60). Le disque de filtrage (52) est mis en rotation rapide et continue afin de placer séquentiellement les filtres dans le trajet optique s'étendant entre une source de lumière à large bande et un échantillon microscopique. Le comptage photonique du rayonnement émis par l'échantillon est synchronisé avec la position des filtres pendant leur rotation à l'aide de marques de synchronisation sur le disque de filtrage. Le même accessoire peut être placé entre l'échantillon et un détecteur pour détecter l'émission de lumière de fréquences diverses.
Abstract:
A hyperspectral optical element for monolithic detectors is provided. In one embodiment, for example a hyperspectral optical element includes a faceplate layer adapted to be mounted on top of a monolithic detector. The faceplate layer comprises a reflective inner surface. A notched layer includes a plurality of notched surfaces and is mounted to the faceplate layer. The notched surfaces oppose the reflective inner surface of the faceplate and define a plurality of variable depth cavities between the reflective inner surface of the faceplate layer and the plurality of notched surfaces of the notched layer. The faceplate layer and the notched layer are substantially transparent to a received signal and the plurality of variable depth cavities provides resonant cavities for one or more wavelengths of the received signal.
Abstract:
A system comprises a base defining a plane perpendicular to an axis, a set of elements mounted on a surface of the base parallel to the axis, and a drive assembly in communication with the base. Each element is positionable within a respective guide channel of a mechanical structure containing optical detectors, and each element includes a plurality of sites generally parallel to the axis for securing an optical filter. The drive assembly is configured to move the base along the axis to position a respective site of each element in the set of elements in the respective guide channel relative to an optical detector.
Abstract:
Spectroscopic system and spectrometers including an optical bandpass filter unit consisting of a plurality of bandpass regions and a spatial encoding unit for encoding discrete frequencies of light passing through the optical filter. The incorporation of the encoding unit allows the spectrometer system to use a detector consisting of one or a small number of elements, rather than using a more expensive detector array as is commonly used with filter-based spectrometers. The system can also include an integrating chamber that collects the light that is not transmitted through the bandpass filter unit and is substantially reflected, and redirects this light to strike the filter unit again, resulting in a significant increase in the optical power passing through the filter. The integrating chamber maximizes the return of the reflected light to the filter assembly and minimizes optical losses. The integrating chamber may be an orthogonal design to preserve the optical geometric characteristics of the light entering the chamber, even after multiple reflections from the optical filter.
Abstract:
A hemispherical detector comprising a plurality of photodetectors (12) arranged in a substantially contiguous array, the array being substantially in the shape of a half-sphere, the half-sphere defining a closed end (50) and an open end (60), the open end (60) defining a substancially circular face. Also provided is a method for constructing a hemispherical detector comprising the steps of making a press mold of the desired shape of the hemispherical detector, pouring a material into the press mold to form a cast, finishing the cast to remove any defects, coating the cast with a coating material, and attaching a plurality of photodetectors to the cast.
Abstract:
The invention provides a spectrometer (10) which includes a filter arrangement (16,18), in addition to any optional filters (20) for limiting an operational wavelength range of the spectrometer, the filter arrangement (16,18) comprising a plurality of broadband optical filters or broadband optical filter areas each of known transmission and being located or selectively locatable in a path of collected incident spectral radiation (44). The spectrometer further includes at least one detector (24) arranged to measure the spectral radiation passing through at least one of the broadband filters located in the path of collected incident spectral radiation, and signal-processing means (34) for recovering the spectrum of the collected spectral radiation from measurements by the detector (24).
Abstract:
An accessory is provided to convert a conventional microscope to a microspectrofluorimeter. The accessory includes a filter disc (52) having bandpass filters (54, 56) separated by opaque segments (58, 60). The filter disc (52) is rapidly and continuously rotated to move the filter sequentially into the optical path between a wideband light source and a microscope sample. Photon counting of radiation from the sample is synchronized to the position of the filters during rotation by means of synchronization marks on the filter disc. The same accessory may be positioned between the sample and a detector to detect emitted light of different frequencies.
Abstract:
A near-infrared and/or visible optical analyzer which is able to measure the concentrations of material in industrial processes. The analyzer is equipped with a number of interference filters (9), mounted in a rotating filter wheel (11). The monochromatic radiation is reflected by the material moving along the optical window (27) of the analyzer. More than one type of detectors (29) are mounted in a detector head (30) to measure the reflected radiation in a wide wavelength range. The amplified and dark current compensated signal is processed by a microprocessor controlled circuit. The reflection optical standard (24) used as a reference in the analyzer periodically intercepts the radiation beam and radiation reflected from the standard is also impinging upon the same detectors. The reflection standard is mounted on a blade (22) rotated by a reduction gear mechanism (20). On the other side of the blade a so called absorption optical standard (25) is mounted, with the help of which the stable operation of the analyzer can be checked.