Light detection and ECL instrumentation

Hamamatsu R4220 and R928 specifications (from www.hamamatsu.com) 

Anode current sensitivity 1% (voltage hysteresis) 0.1% (current hysteresis), 1% (voltage hysteresis) 0.1% (current hysteresis) 

Current flows in the anode circuit of a PMT even when the tube is operated in complete darkness. The DC component of this current is called the anode dark current, or simply the dark current. This current and its resulting noise component usually limit the lower level of PMT light detection as a result, the anode dark current value is nearly always given as part of the data for any tube. 

A commercial CE ECL system fabricated in Changchun Institute of Applied Chemistry, Chinese Academy of Science has been recently reported (9). 

3 Other ECL setups for emitted light intensity measurements 

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