Method and apparatus for use in laser shock peening

A method of amplifying a laser beam in an apparatus for laser shock peening, comprising:

• sequentially amplifying a laser beam generated by the apparatus by a multi-stage amplifier to output an amplified beam, wherein the sequentially amplifying comprises:
• amplifying by a first stage having a first amplifier module configured to first amplify the laser beam having a first energy output from the apparatus, to output a first amplified beam having a second energy, wherein the first stage comprises arranging in a sequential order:
• a first optical isolator, a first vacuum relay imaging module (VRIM), and the first amplifier module, such that the laser beam passes sequentially through the optical isolator, the first VRIM, and the first amplifier module to output the first amplified beam,
• wherein prior to the first amplifying to the second energy, the laser beam is collimated by the first VRIM to yield a larger diameter first collimated beam, and
• amplifying by a second stage having a second amplifier module configured to second amplify the first amplified beam having the second energy to output a second amplified beam having a third energy, wherein the second stage comprises arranged in a sequential order:
• a second VRIM and the second amplifier module, such that the first amplified beam passes sequentially through the second VRIM and the second amplifier module to output the second amplified beam,
• wherein prior to the second amplifying to the third energy, the first amplified beam is collimated by the second VRIM to yield a larger diameter second collimated beam.

An apparatus for use in laser shock peening, the apparatus comprising:

• a diode-pumped solid-state laser (DPSSL) oscillator configured to output a pulsed laser beam having a first energy;
• a modulator configured to receive the pulsed laser beam from the DPSSL oscillator to modify the pulsed laser beam having the first energy and a first temporal profile, to output a beam having the second energy and a second temporal profile;
• and
• an amplifier having multiple stages comprising:
• a first stage having a first amplifier module configured to first amplify the beam having the second energy to output a first amplified beam having a third energy, wherein the first stage comprises arranged in a sequential order:
• a first optical isolator, a first vacuum relay imaging module VRIM, and the first amplifier module, such that the laser beam passes sequentially through the optical isolator, the first VRIM, and the first amplifier module to output the first amplified beam,
• wherein prior to the first amplifying to the third energy, the laser beam is collimated by the first VRIM to yield a larger diameter first collimated beam, and
• a second stage having a second amplifier module configured to second amplify the first amplified beam having the third energy to output a second amplified beam having a fourth energy, wherein the second stage comprises arranged in a sequential order:
• a second VRIM and the second amplifier module, such that the first amplified beam passes sequentially through the second VRIM and the second amplifier module to output the second amplified beam,
• wherein prior to the second amplifying to the fourth energy, the first amplified beam is collimated by the second VRIM to yield a larger diameter second collimated beam.