The timing control which was based on the acoustic velocity of the traveling-wave lens, in the acoustic optical scanner

摘要

(57) Abstract The pixel clock and beam scan timing of the acoustic optical scanner are controlled by the phase locked loop which is driven by acoustic velocity. This phase locked loop includes the adjustment possible variable voltage control pixel clock generator, this generator is controlled by the detector which forms the replica which it is delayed and is attenuated and of the excited ripple mark which is supplied to the ATWL scanner which is used in order to scan the light beam which covers the work piece. Ended of cell transducer converts the advance lens which is induced by pressure to the replica of the electric information of excitation input. Alternative, when the ended of scan optical pick off monitor is used, crossing the range of vision the optical spot which is scanned is detected. As for the respective pixel, the pixel clock just the same proportional quantity speed decrease or speed increasing fit as a fluctuation of the temperature for the end of the ATWL cell regarding the scan of each one, in order for the adjustment in time and the space to be maintained, spatially it is constant vis-a-vis the change of the propagation velocity in ATWL medium.