US 12,470,038 B2
Pulse equalization in Q-switched gas lasers
Vernon Seguin, Windsor, CT (US); David P. Schmelzer, West Hartford, CT (US); Joel Fontanella, Tolland, CT (US); and Peter Rosenthal, West Simsbury, CT (US)
Assigned to Coherent, Inc., Santa Clara, CA (US)
Filed by Coherent, Inc., Santa Clara, CA (US)
Filed on Oct. 28, 2022, as Appl. No. 17/976,642.
Claims priority of provisional application 63/281,044, filed on Nov. 18, 2021.
Prior Publication US 2023/0155342 A1, May 18, 2023
Int. Cl. H01S 3/136 (2006.01); H01S 3/117 (2006.01); H01S 3/13 (2006.01); H01S 3/223 (2006.01)
CPC H01S 3/136 (2013.01) [H01S 3/117 (2013.01); H01S 3/1305 (2013.01); H01S 3/2232 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A Q-switched gas laser apparatus with pulse equalization, comprising:
a gas laser including a laser resonator having a Q-switch operable to switch the laser resonator between a high-loss state and a low-loss state to generate a pulsed laser beam;
a first sensor for obtaining a first measurement of the pulsed laser beam indicative of a laser pulse energy;
a second sensor for obtaining a second measurement of the pulsed laser beam indicative of a laser pulse duration; and
an electronic circuit communicatively coupled between the Q-switch and the first sensor and the second sensor and configured to operate the Q-switch to (a) repeatedly switch the laser resonator between the high-loss and low-loss states to set a repetition rate of laser pulses of the pulsed laser beam, (b) adjust a loss level of the low-loss state, based on the first measurement, to achieve a target laser pulse energy, and (c) adjust, based on the second measurement, a duration of the low-loss state to achieve a target laser pulse duration.