Measurement of Low-Level Light Emission under Labconditions

Summary

The present paper is based on studies by Ruth /1/, Popp /2/ and by many other authors as well, who were confronted again and again with the problematic nature of the exact laboratory measurement of low-level light emission. The results of our investigations shall show that a variety of Conditions has to be considered with the measurement of the spontaneous emission of very low luminous objects. Special emphasis won’t be given to questions which arise in the case of detection by the sensor (e.g. signal-noise-ratio, signal evaluation etc.), but effects will be investigated which have a direct influence on the measuring quantity. These are in particular thermal and stray radiation superimposing on the radiation being measured. It can be indicated by means of theoretical assessments and experimental verification, that a photon flux down to 10 photons per second is undoubtedly detectable with appropriate measurement instruments. The necessary conditions for this outcome shall be demonstrated in this article.