photomultiplier gain

home • the photomultiplier

Gain in a photomultiplier is derived by current amplification. Each dynode amplifies the incident electron current and the overall gain is given by the product of the individual dynode contributions. With many stages of gain, a small photoelectric signal is amplified to a measurable level.

The gain of each dynode is related to the energy of the incident electrons; and hence to the inter-dynode voltage.

In general, a single high voltage power supply is employed, with a resistive voltage divider network, to provide suitable inter-electrode voltages. The more dynode stages in the photomultiplier, the higher is the gain at a specific overall applied voltage and the higher the maximum gain attainable.

For more detailed information, request our brochure "Understanding photomultipliers" via this form.