Abstract: A method for aligning an energy beam to an object in an atom probe is disclosed. The method comprises monitoring at least one parameter indicative of an interaction between the energy beam and the object. A signal is generated in response to the interaction of the energy beam and the object. The signal is then used to effectuate control of the alignment of the energy beam to the object.

Abstract: A clockless time-of-flight interval timer includes a tapped delay line register comprising N buffers that each contribute a substantially identical incremental time delay. A latched version of a START pulse associated with an output of transmitted energy from a laser is propagated through the tapped delay line. A DATA signal representing a detected pulse returned from a target is coupled to a block of four comparators each having a different signal threshold. The output of each comparator block is provided as input to one of four channel registers, each register comprising N D-type flipflops separately but synchronously triggerable by tapped incrementally delayed outputs from the N buffers. Channel register outputs are multiplexed and decoded and interfaced with a microprocessor. The microprocessor determines first signal time over threshold (FOT) information and total time over threshold (TOT) information from the channel registers.