Optical absorption measuring instrument
AssigneeDräger Safety AG & Co. KGaAM
InventorHans Matthiessen
Life of this patent
Estimating the term…
Abstract
An optical absorption measuring instrument for determining the percentage of a component in a fluid shall be improved such that changes in the measuring radiation caused by drift or temperature have only a limited effect on the measuring result. Provisions are made for deflecting the measuring beams (10, 11) from a radiation source (4) to a detector (5) by at least two plane mirrors (71, 72), which are positioned such that the measuring beams (10, 11) emitted by the radiation source (4) are deflected to the detector (5). The surface of each plane mirror (71, 72) is dimensioned to be such that its illuminated surface in the area of the detector (5) is larger than the receiving surface (12) of the detector (5).
Claims20
An optical absorption measuring instrument for determining the percentage of a component in a fluid, the measuring instrument comprising:
- a measuring chamber containing the fluid;
- a radiation source emitting measuring beams;
- at least one detector with a receiving surface sensitive to the measuring beams at a first limiting surface of said measuring chamber;
- at least two plane mirrors at a second limiting surface of said measuring chamber, said second limiting surface being located opposite said first limiting surface, said plane mirrors being positioned at said second limiting surface such that the measuring beams emitted by said radiation source are deflected to the detector, wherein the surface of each plane mirror is dimensioned to be such that an illuminated surface in the area of said at least one detector is larger than said receiving surface.
An optical absorption measuring instrument for determining the percentage of a component in a fluid, the measuring instrument comprising:
- a measuring chamber for a fluid to be measured, said chamber having a first limiting surface and a second limiting surface;
- a radiation source emitting measuring radiation into the chamber;
- a detector with a receiving surface sensitive to the measuring radiation, said receiving surface being provided at or adjacent to said first limiting surface;
- a plurality of plane mirrors at or adjacent to said second limiting surface, said plane mirrors being located opposite said first limiting surface, said plane mirrors being positioned such that measuring radiation emitted by said radiation source is deflected toward said detector, wherein a surface of at least one of said plane mirrors is dimensioned to be such that an illuminated surface in an area of said detector is larger than said receiving surface.
A method for determining the percentage of a component in a fluid by optical absorption measuring, the method comprising the steps of:
- providing a measuring chamber for a fluid to be measured having a first limiting surface and a second limiting surface;
- emitting measuring radiation into the chamber with a radiation source;
- providing a detector with a receiving surface sensitive to the measuring radiation at or adjacent to the first limiting surface;
- providing a plurality of plane mirrors at or adjacent to the second limiting surface;
- locating the plane mirrors opposite the first limiting surface, the plane mirrors being positioned such that measuring radiation emitted by the radiation source is deflected toward the detector;
- and
- dimensioning at least one of the plane mirrors such that an illuminated surface in an area of the detector is larger than the receiving surface.
Dependencies are inferred from the claim text.