Patent ID: 8755103

Claim:
A plasma shutter forming apparatus used in a system configured to generate a first high-density plasma by irradiating a plasma generating target with a first laser pulse and accelerate charged particles in the first high-density plasma, and the plasma shutter forming apparatus configured to generate a plasma shutter comprising a second high-density plasma for blocking the first laser pulse which is returned as a feedback light to upstream of the system without being absorbed by the first high-density plasma, the apparatus comprising: a plasma shutter generating target arranged to form the plasma shutter between the plasma generating target and a focusing optics of the system; a plasma shutter triggering laser irradiator configured to irradiate the plasma shutter generating target with a second laser pulse; a laser beam splitting optics for dividing laser pulses emitted from a laser device into the first laser pulse to irradiate the plasma generating target and the second laser pulse to irradiate the plasma shutter generating target; and an optical delay element for adjusting of the timing of the second laser pulse with the first laser pulse, wherein the second laser pulse from the plasma shutter triggering laser irradiator is directed to the plasma shutter generating target to generate the second high-density plasma and form the plasma shutter, thereby blocking the first laser pulse which is returned as the feedback light.