US 12,034,268 B2
Optical phase locked loops for generating highly-linear frequency chirps
Tianyi Hu, San Diego, CA (US); Jinendra S. Ranka, San Diego, CA (US); Christopher S. Sexton, San Diego, CA (US); Brett A. Spivey, Carlsbad, CA (US); and Kyle D Watson, Carlsbad, CA (US)
Assigned to JASR Systems, LLC, Solana Beach, CA (US)
Filed by JASR Systems, LLC, Solana Beach, CA (US)
Filed on Apr. 16, 2021, as Appl. No. 17/232,492.
Claims priority of provisional application 63/011,497, filed on Apr. 17, 2020.
Prior Publication US 2021/0328402 A1, Oct. 21, 2021
Int. Cl. H01S 5/12 (2021.01); G01B 9/02003 (2022.01); G01B 9/02015 (2022.01); G01B 9/02055 (2022.01); G01S 7/4911 (2020.01); H01S 3/00 (2006.01); H01S 3/13 (2006.01); H01S 5/026 (2006.01); H01S 5/40 (2006.01)
CPC H01S 3/1307 (2013.01) [G01B 9/02003 (2013.01); G01B 9/02029 (2013.01); G01B 9/02072 (2013.04); G01S 7/4911 (2013.01); H01S 3/0014 (2013.01); H01S 3/1305 (2013.01); H01S 5/0264 (2013.01); H01S 5/1246 (2013.01); H01S 5/4012 (2013.01)] 43 Claims
OG exemplary drawing
 
15. A laser system comprising:
a laser;
a power tap configured to split light from the laser into an output arm and a lock arm; and
a phase locked loop including:
a first optical splitter configured to split light from the lock arm into a first arm and a second arm;
a delay line configured to time delay light in an arm chosen from the first arm and the second arm;
a second optical splitter configured to split the light in the first arm into third, fourth, and fifth arms;
a third optical splitter configured to split the light in the second arm into sixth, seventh, and eighth arms;
a first phase shifter configured to phase shift light in the seventh arm relative to light in the sixth arm;
a second phase shifter configured to phase shift light in the eighth arm relative to light in the sixth arm;
a first combiner configured to combine light in the third arm with light in the sixth arm;
a second combiner configured to combine light in the fourth arm with phase shifted light in the seventh arm;
a third combiner configured to combine light in the fifth arm with phase shifted light in the eighth arm;
a first detector configured to detect a first analog electrical signal from light from the first combiner;
a second detector configured to detect a second analog electrical signal from light from the second combiner;
a third detector configured to detect a third analog electrical signal from light from the first combiner; and
a processor configured to generate a frequency correction signal for the laser responsive to the first, second, and third analog electrical signals.