Abstract:
Methods and apparatus (2) for measuring the intensity of light scattered by particles (4) suspended in a sample volume illuminated by an interrogating light beam (12) directed along an input axis, utilizing plural Fourier lenses (17, 52) each arranged for illuminating multiple photodetectors (22, 24, 56). The multiple Fourier lenses (17, 52) can be of different optical powers, for providing low power and high power optical trains (3, 50). A low power optical train (3) provides high resolution measurements of light scattered within a small angular range at low angles relative to the input axis, while a high power optical train (50) provides lower resolution measurements of light scattered within a larger angular range at higher angles.
Abstract:
Le procédé décrit consiste à transmettre une énergie rayonnante vers un élément sonde comportant une surface réfléchissante conique interne et une chambre pour échantillons fluides. Les parties de la lumière qui ont été transmises, partiellement atténuées, ou diffusées par un échantillon fluide dans la chambre pour échantillons sont dirigées par au moins une partie de la surface réfléchissante conique interne vers un organe destiné à recueillir la lumière transmise partiellement atténuée, ou diffusée. Un clapet de distillation incorporé dans l'élément sonde permet d'éliminer les bulles de gaz entraînées contenues dans la chambre. Dans une application spécifique de cette sonde, un analyseur à titrage est combiné avec des circuits de conversion et de traitement de signaux électro-optiques et avec une sonde selon l'invention, pour permettre une détermination colorimétrique par titrage des points terminaux en vue de mesurer la teneur en acides gras libres d'un fluide tel qu'une huile ou une graisse comestibles.
Abstract:
On a mis au point des procédés et un appareil (2) de mesure de l'intensité de la lumière diffusée par des particules (4) en suspension dans un volume d'échantillon éclairé par un faisceau de lumière d'interrogation (12) orienté le long d'un axe d'entrée, utilisant plusieurs lentilles de Fourier (17, 52) chacune agencée pour éclairer des photodétecteurs multiples (22, 24, 56). Lesdites lentilles de Fourier multiples (17, 52) peuvent être de différentes puissances optiques, afin de produire des trains optiques (3, 50) de faible puissance et de puissance élevée. Un train optique (3) de faible puissance produit de mesures de résolution élevée de lumière diffusée dans une plage angulaire réduite à des angles faibles par rapport à l'axe d'entrée, tandis qu'un train optique (50) de forte puissance produit des mesures de faible résolution de lumière diffusée dans une plage angulaire plus grande à des angles supérieurs.
Abstract:
Reflectance apparatus is disclosed for obtaining measurement of nonspecular reflected light in which controlled light rays are directed along a transmission path from a light source (32) through a plurality of light traps (44) to expose or illuminate a specimen and nonspecular reflected light is passed from the specimen (42) through the light traps (44) along a transmission path to one or more detectors (36) where the nonspecular reflected light is measured, the detector's field of view being larger than the illuminated area of the specimen (42) over a wide range of specimen to source (32) and detector (36) distances.
Abstract:
The invention is directed to a sample cell and a holder for a sample cell. The sample cell forming a flow-thru sample cell and being mounted in a radiation detecting device, specifically a fluorescence liquid chromatography detector. The holder comprises a base, a first mount for the sample cell carried by said base, an arm, a second mount for the sample cell carried by said arm, means for coupling said base and said arm for pivotal movement one relative to the other about an axis between a first position with said first mount and said second mount in spaced relationship one with respect to the other on opposite sides of a sample cell to hold the sample cell therebetween and a second position with said first mount and said second mount further spaced one from the other than in said first position to enable removal and disposition of a sample cell therebetween, said pivotal coupling means including a pair of elements on said axis and cooperable surfaces respectively carried by said arm and said base and engaged with said elements to enable relative pivotal movement of said arm and said base about said axis, a pair of said surfaces and one of said elements having cooperating shapes to prevent relative movement of said arm and said base in a direction parallel to said axis and another pair of said surfaces and the other of said elements having cooperating shapes to permit relative movement on the surfaces of said other pair thereof in an axial direction whereby repeatable accurate alignment of said mounts one with respect to the other in said first position thereof is obtained enabling accurate location of the sample cell therebetween.
Abstract:
In a spectrofluorimeter, comprising an excitation monochromator (18) and an emission monochromator (38), ellipsoidal reflectors (30) (34) are provided forfocussing radiation to and from the sample cell (12). Baffles (50) (52) are also provided on respectively excitation and emission beams. Sample cell (12) is formed of a section of quartz tubing with chamfered ends (64) (66) and is clamped through tubular seals (73,74) by tubular mounts (60,62). One mount is carried by a base (80), the other one by an arm (86), arm and base being coupled for pivotal movement one relative to the other. The pivotal coupling includes a pair of elements (100, 102) on the pivotal axis and cooperable surfaces on arm and base.
Abstract:
Laser-based spectroscopy systems and methods including a laser source that emits a beam of radiation, an optical resonant cavity having at least two cavity mirrors, and at least one beam filtering element positioned along a path of the beam external to the cavity and having a front surface, wherein the front surface is oriented such that an intersection of the beam and the surface is at an angle, such as the Brewster's angle or a pseudo-Brewster's, that reduces or eliminates reflection of a predominant polarization component of the beam by the filtering element.
Abstract:
The present invention relates to a microchip 1 having a translucent member 11, a flow channel 10 or a cell formed at a side of the translucent member 11 where light enters, and an aperture 16 formed at a position corresponding to the flow channel 10 or the cell at a side of a translucent member 10 where light goes out. The aperture 16 has a light go-through surface 17 which causes light flux being emitted from the flow channel 10 or the cell to go through and a light reflective surface 18 that totally reflects the incident light flux. A width size W1 of the light go-through surface 17 is smaller than a width size W2 of the flow channel 10 or the cell.
Abstract:
Apparatus comprising: a sensor configured to generate sensor output dependent on an intensity of light incident on the sensor and having a field of view directed at an external surface in use; an illumination source configured to emit light onto the external surface in use; a window located such as to allow light to pass from the illumination source to the external surface and to allow light to pass to the sensor from the external surface in use; a shield coupled to or integral with the window, the shield being substantially opaque to substantially all wavelengths of light detectable by the sensor and defining an aperture which limits the field of view of the sensor; and a processor configured to use the sensor output to determine information associated with reflection characteristics of the external surface.