Modular digital box-car for applications in pulsed laser spectroscopy

Abstract

A digital box-car, designed to work with sources producing signals composed of single pulses or series of pulses, is described. Thanks to its modular design, the system can be employed as a single-photon counting or as a coincidence unit in many experimental situations. The box-car is based on a digitally controlled delay line, producing a delay in the interval 17 ns–327.692 μs by 5 ns steps, a fast gate with an opening time adjustable in the range 10 ns–20.0 μs, and an 8-bit binary counter operating at a maximum frequency of 250 MHz. It also employs two pulse amplifiers, accepting negative pulses with a duration larger than 2 ns and an amplitude in the range 30–500 mV, and a fan-out unit. Applications to fluorescence and ion detection in experiments involving pulsed laser sources are briefly discussed.

Time-of-flight repeller circuit application in laser ablation experiment

“…The zinc ions were detected shot-to-shot by the tandem multichannel plate (MCP) detector. The signal composed of a train of pulses is amplified [4] and fed to an input of a real time multichannel scaler (RTMS) [5,6]. In the case of a signal obtained from the multichannel plates when the laser saturate the plasma (the signal then is not composed of a train of countable pulses), the LeCroy 9370, 1GHz digital oscilloscope was used.…”

A High-Speed Fully Digital Phase-Synchronizer Implemented in a Field Programmable Gate Array Device

“…Unlike the well-known box-car constructions [27], the presented CC system stores information only about the occurrence of photons in appropriate time-gates. The basic modules of system include: a control unit (CU), a phase synchronizer (DPS), a time-gate generator (TGG) with a fast counter (not shown in Fig.…”