How does optical design affect instrument time stability?

uv-vis-faq-instrument-design-optical-design-instrument-time-stability

As an example of the difference in time stability between the configurations, the fluctuations in measurement values over time (drift) were compared using a single-beam instrument (blue line) and a double-beam instrument (red line). The top figure shows the results from placing the single beam and double beam instruments in the same room and using each to obtain time-course measurements for one hour at 5-second intervals. The double-beam instrument had less time variability than the single-beam instrument.

This means the double-beam system provides more stable measurement values than the single-beam system. The single-beam system requires waiting until the light source and detector stabilize, performing frequent blank corrections to minimize such time variability. A summary of single-beam and double-beam characteristics is shown in the table at bottom.

Back to Index