| 摘要 |
<p>A photometric appts. to measure the concn. of a component in a mixt., e.g. a gas concn., includes in the path of the rays before the detector an interference filter which can be tilted and locked in the tilted position. An evaluation circuit compiles the ratio of the detector signal caused by rays, attenuated by the desired component, to the sum of the signals caused by unattenuated rays. This ensures that the reading is not affected by other components which are present in the mixt. The cross sensitivity of the photometric appts. is thereby removed.</p> |
