| 摘要 |
The invention relates to a measuring device 2 for determining the concentration of gases by radiation absorption with at least one radiation source 1 for generating radiation, with a measuring cell 2 arranged downstream of the radiation source 1 in the radiation direction, in which measuring cell 2 the medium to be measured is located, with at least one radiation detector 3, 3', which the radiation strikes after being passed through the measuring cell 2, with a radiation guide arrangement 2, by means of which the radiation is guided to the radiation detector, wherein the radiation guide arrangement comprises a main optics unit, which on the one hand has an optics element 4, so that the punctiform radiation source is imaged in a rod-shaped radiation spot 5 running along a preferential direction 6, and which on the other hand comprises parallel reflection surfaces 7, 7' extending at right angles to the preferential direction 6, at whose inner surfaces the radiation is totally reflected between the optics element 4 and the radiation detector 3, 3'. |
