The PDM TTL series photodetector modules are a versatile and innovative solution designed for precision photon counting applications. These modules are available in both cylindrical and rectangular formats, providing flexibility in integration and application. With a choice of 25mm and 30mm diameter photomultiplier tubes (PMTs), these modules cater to a wide range of requirements. The high voltage and discriminator threshold levels are pre-set for optimal performance, ensuring efficient operation by simply connecting to a +5V power supply.

One of the standout features of the PDM TTL series is its wide dynamic range, capable of handling up to 100 million counts per second (Mcps). This is achieved through a sophisticated dead time correction mechanism that compensates for non-linearity at high count rates due to pulse pile-up. The correction formula, N = n/(1-nT), allows for deviation from linearity to remain within ±5% at 100Mcps, ensuring accurate and reliable measurements.

These photodetector modules are not only high-performing but also user-friendly, with the capability to attach a light fiber guide for enhanced functionality. Additionally, they are equipped with magnetic and electrostatic shielding to protect against environmental interference. For those seeking cost-effective options, the rectangular types offer a lower-cost alternative without compromising on quality or performance.