Optics: measuring and testing – By shade or color – With color transmitting filter
Patent
1998-03-20
2000-07-04
Evans, F. L.
Optics: measuring and testing
By shade or color
With color transmitting filter
2504581, G01N 2101, G01N 2164
Patent
active
060846801
DESCRIPTION:
BRIEF SUMMARY
FIELD OF TECHNOLOGY
The invention relates to instrument technology and concerns optical analysers used in laboratories, in which analysers measuring light is directed from a sample to the detector. Analysers according to the invention can be used, for example, in assays of clinical chemistry and food technology. The invention is particularly suited for use in fluorometers and luminometers.
BACKGROUND
Determinations based on the measurement of the optical properties of a sample are in laboratories usually carried out on plates having a plurality of reaction wells. Photometric measuring is in such a case best performed through the plate in the vertical direction. The measuring light is directed to the plate either from above or from below (cf., for example, WO-82/00356).
Fluorometric measurement through a plate is not particularly recommendable, since in such a case there travels through the plate also a large amount of excitation light, which complicates the measuring of emitted light. In addition, background fluorescence possibly due to the material of the plate constitutes a problem. In most present-day fluorometers available for routine assays, excitation light is directed to the plate from above, and also emitted radiation is collected from above.
In luminometers, the light emitted from the sample is in general directed to the detector from above.
In certain fluorometric assays, the sample is inhomogeneous so that the concentration of the analyte being measured is highest at the bottom of the plate well. This is especially the case in certain samples containing cell cultures. In such a case it would usually be best to direct both the excitation light to the sample and the emitted light from the sample through the bottom of the plate, in order that the solution above the bottom layer should not disturb the measuring.
There are known fluorometers in which the measuring can be carried out either from above or from below (e.g. Series 7600 Microplate Fluorometer, Cambridge Technology, Inc., USA). In such an apparatus the source of light and the detector are fixedly mounted. Excitation light is directed from the source of light to the plate and emitted light is directed from the plate to the detector by means of optical-fiber bundles. The end of a fiber bundle may be placed either above or below the plate. One problem in these apparatuses is the high price of the fiber optics suitable for the purpose.
DESCRIPTION OF THE INVENTION
An improved analyser for measuring optical properties of a sample has now been invented. Preferred embodiments of the invention are stated in the other claims.
According to the first independent characteristic of the invention, the apparatus has, placeable either above or below the sample, an optics module having a detector for the measuring of the light emitted from the sample. Thus the apparatus can be used for carrying out the measuring either from above or from below, depending on the need. However, the apparatus does not require fiber optics for directing light to the detector, since the necessary optical means constitute part of the movable module and can thus be mounted fixedly in relation to the detector.
The apparatus may be, for example, a fluorometer, luminometer, nephelometer, photometer, or any combination of these.
In general the apparatus also has a source of light for directing light to the sample. In practice, apparatuses which are solely luminometers do not need a source of light. The source of light may be separate from the optics module and capable of being mounted either above or below the sample.
Preferably the source of light is part of the optics module. This feature is especially well suited for fluorometers. In this case both excitation light to the sample and emitted light from the sample are directed on the same side of the sample. Precisely in fluorometers, in which the fiber optics usable within the UV range is especially expensive, the avoiding of fiber optics is a particular advantage. Fiber optics also causes background fluorescence, which is t
REFERENCES:
patent: 3421821 (1969-01-01), Alessi
patent: 4053235 (1977-10-01), Hampton et al.
patent: 4426154 (1984-01-01), Steen
patent: 4501970 (1985-02-01), Nelson
patent: 4945250 (1990-07-01), Bowen et al.
patent: 5091652 (1992-02-01), Mathies et al.
patent: 5108179 (1992-04-01), Myers
patent: 5147609 (1992-09-01), Grenner
patent: 5360523 (1994-11-01), Middendorf et al.
patent: 5515169 (1996-05-01), Cargill et al.
Karmeniemi Timo
Priha Matti
Tupakka Heikki
Tuunanen Jukka
Evans F. L.
Labsystems Oy
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