A method for generating a series of pulses in a laser device, said laser device, comprising: at least a master oscillator, MO adapted to emit seed pulses separated in time by a period(τ OSC), a regenerative amplifier, RA, a polarization switching device comprising: a first high-voltage switch (148, 156) and a second high-voltage switch (150, 158) adapted to apply a voltage to the polarization switching device; the method comprising: a first injection step, wherein: the polarization switching device is set to a first intermediate operating mode by applying a first intermediate voltage (U 1) to the polarization switching device during a first time interval (T 1), whereby the seed laser pulses are injected into the RA forming a seed burst; followed by a second amplification step, wherein: the polarization device is set to a locked mode by applying a locking voltage (U λ/4) to the polarization switching device during a second interval (T 2), whereby the injected seed laser pulses are amplified; followed by a third ejection step, wherein the polarization switching device is set to a second intermediate operating mode by applying a second intermediate voltage (U 2) to the polarization switching device during a third time interval (T 3), whereby the amplified seed pulses are partial ejected from the RA on each round trip in the RA to create a multiple burst laser pulses; whereby: the first intermediate voltage (U 1), the locking voltage (U λ/4) and the second intermediate voltage (U 2) are supplied by the first high-voltage switch (148, 156) and the second high-voltage switch (150, 158), and the locking voltage (U λ/4) is equal to the sum of the first intermediate voltage (U 1) and the second intermediate voltage (U 2), and a time gap (Δτ) between injected injected seed laser pulses is tuned by adjusting an RA-round-trip time (τ RA) in the RA by shortening or elongating an optical path within the RA and MO. at least a master oscillator, MO adapted to emit seed pulses separated in time by a period(τ OSC), a regenerative amplifier, RA, a polarization switching device comprising: a first high-voltage switch (148, 156) and a second high-voltage switch (150, 158) adapted to apply a voltage to the polarization switching device; the method comprising: a first injection step, wherein: the polarization switching device is set to a first intermediate operating mode by applying a first intermediate voltage (U 1) to the polarization switching device during a first time interval (T 1), whereby the seed laser pulses are injected into the RA forming a seed burst; followed by a second amplification step, wherein: the polarization device is set to a locked mode by applying a locking voltage (U λ/4) to the polarization switching device during a second interval (T 2), whereby the injected seed laser pulses are amplified; followed by a third ejection step, wherein the polarization switching device is set to a second intermediate operating mode by applying a second intermediate voltage (U 2) to the polarization switching device during a third time interval (T 3), whereby the amplified seed pulses are partial ejected from the RA on each round trip in the RA to create a multiple burst laser pulses; whereby: the first intermediate voltage (U 1), the locking voltage (U λ/4) and the second intermediate voltage (U 2) are supplied by the first high-voltage switch (148, 156) and the second high-voltage switch (150, 158), and the locking voltage (U λ/4) is equal to the sum of the first intermediate voltage (U 1) and the second intermediate voltage (U 2), and a time gap (Δτ) between injected injected seed laser pulses is tuned by adjusting an RA-round-trip time (τ RA) in the RA by shortening or elongating an optical path within the RA and MO. a first injection step, wherein: the polarization switching device is set to a first intermediate operating mode by applying a first intermediate voltage (U 1) to the polarization switching device during a first time interval (T 1), whereby the seed laser pulses are injected into the RA forming a seed burst; followed by a second amplification step, wherein: the polarization device is set to a locked mode by applying a locking voltage (U λ/4) to the polarization switching device during a second interval (T 2), whereby the injected seed laser pulses are amplified; followed by a third ejection step, wherein the polarization switching device is set to a second intermediate operating mode by applying a second intermediate voltage (U 2) to the polarization switching device during a third time interval (T 3), whereby the amplified seed pulses are partial ejected from the RA on each round trip in the RA to create a multiple burst laser pulses; whereby: the first intermediate voltage (U 1), the locking voltage (U λ/4) and the second intermediate voltage (U 2) are supplied by the first high-voltage switch (148, 156) and the second high-voltage switch (150, 158), and the locking voltage (U λ/4) is equal to the sum of the first intermediate voltage (U 1) and the second intermediate voltage (U 2), and a time gap (Δτ) between injected injected seed laser pulses is tuned by adjusting an RA-round-trip time (τ RA) in the RA by shortening or elongating an optical path within the RA and MO.