| 摘要 |
A laser-based material processing method, system and subsystem for use therein for precision energy control are provided, wherein a bulk attenuator is switched across an RF driver output to greatly lower the overall RF output and resulting laser energy per pulse. The value of the attenuator determines the range of energies achievable, pj or fractions of pj's. More than one attenuator and switch can be used to achieve multiple energy ranges. After the bulk attenuator is switched in, the laser energy is greatly reduced and the RF driver can then be run again near full RF power where the SNR is much better. The input voltage from a DAC is also much higher so it is also not at the low end of its range where it is also noisy due to poor SNR. The method and system provides increased dynamic range, greater extinction (lower possible energies), better accuracy and stability due to higher SNR of the DAC input voltage and higher SNR in the RF driver.
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