Photon counting is the fundamental method for extracting the maximum information from a weak light signal. Coupling an amplifier-descriminator to a photomultiplier achieves this.
An amplifier-discriminator combines a fast amplifier and a fixed-threshold discriminator with an overall sensitivity of approximately one millivolt. With the gain of the photomultiplier optimised, photon counting with a high signal to noise ratio and stability can be achieved up to count rates of 100 MHz.
ET Enterprises offers a range of amplifier-discriminators with output logic levels compatible with commercially available counters. Please refer to the section on the CT2 counter/timer module. A cable, LEADAD6CT2, is available to connect the AD6 to the CT2, and powers the AD6.
The range is summarised in the table below.
|Amplifier Descriminator Selection Guide|
|AD2||50||-0.5 to -2.5||25, 40, 80*||ECL||+5V, 25mA
|AD3||50||-2 to -5||10 to 100||ECL||-5V, 65mA|
|AD7||50||-2 to -5||24||TTL**||+5V, 10mA|
* preset with external links, please specify when ordering, easily reset
** not suitbale for use with fast counters
Amplifier-discriminators are available as modules in metal cases with BNC input connector and 9-way D-connector output and LV power connection, view an outline drawing here. The AD7, which is pcb mounting, is supplied in a metal case. View an outline drawing here. Examples are also shown in the photograph on this page. They can also be incorporated into housings; please refer to the section on housings.
Read about amplifier-discriminator options here.