Patent ID: 8278595
Filing Date: 2012-10-02
Classification: B23K

Abstract:
1. A method of triggering emission of laser pulses directed for processing a target specimen, the laser pulses propagating along a beam axis and the target specimen mounted to a support, the beam axis and support moving relative to each other at a velocity to process the target specimen by incidence of the laser pulses at specified target specimen locations, and the specified target specimen locations being associated with laser pulse trigger positions on the target specimen, comprising: performing, at multiple time-displaced measurement intervals corresponding to a measurements sampling rate, measurements of relative positions between the beam axis and the support to acquire measured relative position data; estimating relative position data for different times within each of the multiple time-displaced measurement intervals, the estimated relative position data corresponding to extrapolated relative positions between the beam axis and the support at the different times corresponding to an extrapolated position data sampling rate that is substantially greater than the measurements sampling rate, and, for each of the multiple time-displaced measurement intervals, the extrapolated relative positions being derived from values of the measured relative position data, velocity, and time elapsed within the time-displaced measurement interval; comparing the estimated relative position data with the laser pulse trigger positions associated with the specified target specimen locations to determine occurrence of the beam axis within a trigger window associated with a selected one of the specified target specimen locations; establishing the trigger window in accordance with a ratio of the measurements sampling rate to the extrapolated position data sampling rate; and in response to the determination of the occurrence of the beam axis within the trigger window, triggering emission of a laser pulse to process the target specimen at the selected one of the specified target specimen locations.