# US 10,765,478 B2 · Picosecond optical radiation systems and methods of use > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,765,478 B2 - Document ID: US10765478B2 - Status: Granted - Kind: B2 - Application number: 16/363,655 - Filed: 2019-03-25 - Published: 2019-07-18 - Granted: 2020-09-08 - Earliest claimed: 2013-03-15 - Assignees: Cynosurce, LLC - Applicants: Cynosure, LLC - Inventors: Rafael Armando Sierra; Mirko Georgiev Mirkov - Web page: https://patentgrep.com/patent/US10765478B2 ## CPC - A61B 18/203: {applying laser energy to the outside of the body} - A61N 5/0616: {Skin treatment other than tanning} - H01S 3/0627: {the resonator being monolithic, e.g. microlaser} - H01S 3/08018: Mode suppression - H01S 3/094076: {Pulsed or modulated pumping (H01S3/1024 takes precedence)} - H01S 3/1024: {for pulse generation} - H01S 3/1106: Mode locking - H01S 3/1109: Active mode locking - H01S 3/1121: {Harmonically mode locking lasers, e.g. modulation frequency equals multiple integers or a fraction of the resonator roundtrip time} - A61B 2018/0047: {Upper parts of the skin, e.g. skin peeling or treatment of wrinkles} - A61N 5/067: using laser light - H01S 3/0092: {Nonlinear frequency conversion, e.g. second harmonic generation [SHG] or sum- or difference-frequency generation outside the laser cavity (nonlinear frequency conversion per se G02F1/35)} - H01S 3/08054: {Passive cavity elements acting on the polarization, e.g. a polarizer for branching or walk-off compensation (quarter-wave plates in a Q-switch laser H01S3/1124, H01S3/115)} - H01S 3/093: focusing or directing the excitation energy into the active medium - H01S 3/094038: {End pumping} - H01S 3/094084: {with pump light recycling, i.e. with reinjection of the unused pump light, e.g. by reflectors or circulators} - H01S 3/107: using electro-optic devices, e.g. exhibiting Pockels or Kerr effect {(H01S3/1061, H01S3/1063, H01S3/1065 take precedence)} - H01S 3/1611: {neodymium} - H01S 3/1623: {chromium, e.g. Alexandrite} - H01S 3/1633: {BeAl2O4, i.e. Chrysoberyl} - H01S 3/1643: {YAG} - H01S 3/1673: {YVO4 [YVO]} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - A61N: ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY (measurement of bioelectric currents A61B; surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body A61B18/00; anaesthetic apparatus in general A61M; incandescent lamps H01K; infrared radiators for heating H05B) - H01S: DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL ## Abstract Methods, systems and apparatus are disclosed for delivery of pulsed treatment radiation by employing a pump radiation source generating picosecond pulses at a first wavelength, and a frequency-shifting resonator having a lasing medium and resonant cavity configured to receive the picosecond pulses from the pump source at the first wavelength and to emit radiation at a second wavelength in response thereto, wherein the resonant cavity of the frequency-shifting resonator has a round trip time shorter than the duration of the picosecond pulses generated by the pump radiation source. Methods, systems and apparatus are also disclosed for providing beam uniformity and a sub-harmonic resonator. ## Claims ### Claim 1 An apparatus for delivery of pulsed treatment radiation comprising: a pump radiation source generating pumping pulses at a first wavelength, and a wavelength-shifting resonator having a lasing medium and resonant cavity configured to receive the pumping pulses from the pump radiation source at the first wavelength and to emit pulsed treatment radiation at a second wavelength with a pulse duration shorter than the pulse duration of the pump radiation source in response thereto, wherein the resonant cavity of the wavelength-shifting resonator has a round trip time shorter than the duration of the pumping pulses. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the wavelength-shifting resonator operates without use of a modelocker or a Q-switch. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the wavelength-shifting resonator emits a subnanosecond pulse. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the wavelength-shifting resonator has a cavity length less than 10 millimeters. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein the lasing medium of the wavelength-shifting resonator comprises a neodymium-doped crystal. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein the lasing medium of the wavelength-shifting resonator comprises a solid state crystal medium selected from the group consisting of neodymium-doped yttrium-aluminum garnet (Nd:YAG) crystals, neodymium-doped pervoskite (Nd:YAP or Nd:YAlO3) crystals, neodymium-doped yttrium-lithium-fluoride (Nd:YAF) crystals, and neodymium-doped, vanadate (Nd:YVO4) crystals. ### Claim 7 (depends on 1) The apparatus of claim 1, further comprising a polarizer embedded within the resonant cavity of the wavelength-shifting resonator. ### Claim 8 (depends on 1) The apparatus of claim 1, wherein the lasing medium of the wavelength-shifting resonator is a polarizing medium. ### Claim 9 (depends on 1) The apparatus of claim 1, further comprising a frequency-doubling crystal. ### Claim 10 (depends on 9) The apparatus of claim 9, wherein the frequency-doubling crystal comprises a nonlinear crystal material. ### Claim 11 (depends on 9) The apparatus of claim 9, wherein the frequency-doubling waveguide comprises a lithium triborate (LiB3O5) material or a KTP material. ### Claim 12 (depends on 1) The apparatus of claim 1, wherein the pump radiation source is a mode-locked laser. ### Claim 13 (depends on 12) The apparatus of claim 12, wherein the mode-locked laser comprises an alexandrite laser. ### Claim 14 (depends on 12) The apparatus of claim 12, wherein the mode-locked laser generates pulsed laser energy having at least about 100 mJ/pulse. ### Claim 15 (depends on 1) The apparatus of claim 1, further comprising a treatment beam delivery system configured to apply a treatment beam to a patient's skin. ### Claim 16 (depends on 1) The apparatus of claim 1, wherein the wavelength-shifting resonator emits a laser energy having at least about 100 mJ/pulse. ### Claim 17 A method of delivering pulsed treatment radiation comprising: generating pumping pulses, using a pump radiation source, wherein one or more pumping pulses are at a first wavelength and a first pulse duration; transmitting the pumping pulses to a resonant cavity of a wavelength-shifting resonator; and emitting pulsed treatment radiation at a second wavelength from the wavelength-shifting resonator, wherein one or more pulses of the pulsed treatment radiation have a second pulse duration, the second pulse duration shorter than first pulse duration, wherein the resonant cavity has a round trip time shorter than the duration of the pumping pulses. ### Claim 18 (depends on 17) The method of claim 17 further comprising applying a treatment beam to a patient. ### Claim 19 (depends on 17) The method of claim 17 wherein the pulsed treatment radiation comprises a subnanosecond pulse. ### Claim 20 (depends on 17) The method of claim 17 further comprising applying one or more subnanosecond pulses to a patient. ### Claim 21 (depends on 17) The method of claim 17 further comprising applying one or more subnanosecond pulses to a tattoo or a region of skin pigmentation. ### Claim 22 (depends on 17) The method of claim 17, wherein the wavelength-shifting resonator emits a laser energy having at least about 100 mJ/pulse.