Patents by Inventor Liyue Mu

Liyue Mu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8137340
    Abstract: The present invention discloses a high power diode-pumped laser for laser ablation of soft tissue. The present invention contemplates to operate the high power diode-pumped solid-state laser at a continuous Q-switching mode and at a big number of transverse modes. The present invention also contemplates to reduce beam divergence and beam spot size and thus to increase power density of the laser on target tissue to improve the speed of tissue ablation. The present invention further contemplates to minimize power consumption such that external water-cooling or secondary cooling loop can be eliminated. The present invention even further contemplates to implement combined mechanisms to protect intracavity optics from power damage. Finally, the present invention contemplates hospitals and surgeon offices to use the high power diode-pumped laser for soft tissue ablation with standard electrical wall-plug outlet and elimination of inconvenient external water-cooling or secondary cooling loop.
    Type: Grant
    Filed: June 17, 2005
    Date of Patent: March 20, 2012
    Assignee: Applied Harmonics Corporation
    Inventors: Ming Lai, Liyue Mu, Kangze Cai, Weiguo Luo
  • Patent number: 7862556
    Abstract: A surgical system that ablates soft tissue. The system may include a fiber laser oscillator as the gain medium that emits electromagnetic radiation. The system may process the electromagnetic radiation, and direct the electromagnetic radiation on to the soft tissue to be ablated. Due at least in part to the nature of the electromagnetic radiation emitted by the fiber laser oscillator, the system may provide various enhancements, such as a higher power conversion efficiency, a longer lifetime, less heat dissipation, a more compact design, and/or other enhancements, for example. The system may also generate electromagnetic radiation with a relatively high beam quality. This may reduce beam divergence and beam spot size on targeted soft tissue, thereby enhancing power density in the electromagnetic radiation guided to the soft tissue. This enhanced power density may facilitate effective ablation.
    Type: Grant
    Filed: June 19, 2006
    Date of Patent: January 4, 2011
    Assignee: Applied Harmonics Corporation
    Inventors: Liyue Mu, Ming Lai, Kangze Cai, Weiguo Luo
  • Patent number: 7769059
    Abstract: The present invention discloses a high power Q-switched, intracavity frequency-doubled laser for laser ablation of soft tissue. Operating a high power Q-switched laser in a frequent on-off mode is highly desirable for laser prostatectomy. Giant first pulse may occur when a Q-switched laser is switched from laser-ready mode to pulse-on mode due to sudden depletion of stored energy in the gain medium. Such a giant first pulse may cause power damage of intracavity optics. Besides, temperature shock induced by sudden onset of a high power pulse train may cause optical damage on surface coating of intracavity optics. The present invention contemplates to suppress these giant first pulses and temperature shocks through pre-lasing and ramping profile of laser parameters. Reliable and frequent on-off operation of a diode-pumped, Q-switched, frequency-doubled Nd:YAG laser is demonstrated for output power up to 100 W.
    Type: Grant
    Filed: December 21, 2007
    Date of Patent: August 3, 2010
    Assignee: Applied Harmonics Corporation
    Inventors: Liyue Mu, Ming Lai, Kangze Cai, Weiguo Luo, Libo Zeng
  • Publication number: 20080095201
    Abstract: The present invention discloses a high power Q-switched, intracavity frequency-doubled laser for laser ablation of soft tissue. Operating a high power Q-switched laser in a frequent on-off mode is highly desirable for laser prostatectomy. Giant first pulse may occur when a Q-switched laser is switched from laser-ready mode to pulse-on mode due to sudden depletion of stored energy in the gain medium. Such a giant first pulse may cause power damage of intracavity optics. Besides, temperature shock induced by sudden onset of a high power pulse train may cause optical damage on surface coating of intracavity optics. The present invention contemplates to suppress these giant first pulses and temperature shocks through pre-lasing and ramping profile of laser parameters. Reliable and frequent on-off operation of a diode-pumped, Q-switched, frequency-doubled Nd:YAG laser is demonstrated for output power up to 100 W.
    Type: Application
    Filed: December 21, 2007
    Publication date: April 24, 2008
    Inventors: Liyue Mu, Ming Lai, Kangze Cai, Weiguo Luo, Libo Zeng
  • Publication number: 20080086118
    Abstract: The present invention fulfils a need to advance a diode-pumped solid-state laser (DPSSL) and to employ laser-induced thermal explosive ablation (LITEA) for prostate surgery. The present invention operates a quasi-CW Q-switched DPSSL at a lower repetition rate of 5 kHz to 20 kHz to produce bigger pulse energy of 2.5 mJ to 10 mJ, while maintaining optimal average power. The present invention also employs two AO Q-switches or one EO Q-switch to obtain shorter pulse duration of 40 ns to 150 ns and to obtain higher peak power of 50 kW to 100 kW, leading to a pulse fluence of 250 mJ/cm2 to 1000 mJ/cm2 on target tissues. The present invention further applies electronic control to suppress amplitude fluctuation below 5% to ensure smoother ablation profile.
    Type: Application
    Filed: May 17, 2007
    Publication date: April 10, 2008
    Applicant: Applied Harmonics Corporation
    Inventors: Ming Lai, Liyue Mu, Kangze Cai, Weiguo Luo
  • Patent number: 7313155
    Abstract: The present invention discloses a high power Q-switched, intracavity frequency-doubled laser for laser ablation of soft tissue. Operating a high power Q-switched laser in a frequent on-off mode is highly desirable for laser prostatectomy. Giant first pulse may occur when a Q-switched laser is switched from laser-ready mode to pulse-on mode due to sudden depletion of stored energy in the gain medium. Such a giant first pulse may cause power damage of intracavity optics. Besides, temperature shock induced by sudden onset of a high power pulse train may cause optical damage on surface coating of intracavity optics. The present invention contemplates to suppress these giant first pulses and temperature shocks through pre-lasing and ramping profile of laser parameters. Reliable and frequent on-off operation of a diode-pumped, Q-switched, frequency-doubled Nd:YAG laser is demonstrated for output power up to 100 W.
    Type: Grant
    Filed: February 12, 2005
    Date of Patent: December 25, 2007
    Inventors: Liyue Mu, Ming Lai, Kangze Cai, Weiguo Luo, Libo Zeng
  • Publication number: 20070038207
    Abstract: A surgical system that ablates soft tissue. The system may include a fiber laser oscillator as the gain medium that emits electromagnetic radiation. The system may process the electromagnetic radiation, and direct the electromagnetic radiation on to the soft tissue to be ablated. Due at least in part to the nature of the electromagnetic radiation emitted by the fiber laser oscillator, the system may provide various enhancements, such as a higher power conversion efficiency, a longer lifetime, less heat dissipation, a more compact design, and/or other enhancements, for example. The system may also generate electromagnetic radiation with a relatively high beam quality. This may reduce beam divergence and beam spot size on targeted soft tissue, thereby enhancing power density in the electromagnetic radiation guided to the soft tissue. This enhanced power density may facilitate effective ablation.
    Type: Application
    Filed: June 19, 2006
    Publication date: February 15, 2007
    Inventors: Liyue Mu, Ming Lai, Kangze Cai, Weiguo Luo
  • Publication number: 20050288653
    Abstract: The present invention discloses a high power diode-pumped laser for laser ablation of soft tissue. The present invention contemplates to operate the high power diode-pumped solid-state laser at a continuous Q-switching mode and at a big number of transverse modes. The present invention also contemplates to reduce beam divergence and beam spot size and thus to increase power density of the laser on target tissue to improve the speed of tissue ablation. The present invention further contemplates to minimize power consumption such that external water-cooling or secondary cooling loop can be eliminated. The present invention even further contemplates to implement combined mechanisms to protect intracavity optics from power damage. Finally, the present invention contemplates hospitals and surgeon offices to use the high power diode-pumped laser for soft tissue ablation with standard electrical wall-plug outlet and elimination of inconvenient external water-cooling or secondary cooling loop.
    Type: Application
    Filed: June 17, 2005
    Publication date: December 29, 2005
    Applicant: Applied Harmonics Corporation
    Inventors: Ming Lai, Liyue Mu, Kangze Cai, Weiguo Luo
  • Publication number: 20010036208
    Abstract: This invention relates to improving the low frequency laser light conversion efficiency by implementing a focusing device to increase the power density inside a non-linear medium and a sub-resonator that resonates both a second harmonic light and a third or higher harmonic light. A wave front compensation device is designed for this invention. The wave front compensation device compensates part of the wave front distortion, which is caused by the sub-cavity when the focused fundamental laser beam passes through.
    Type: Application
    Filed: March 7, 2001
    Publication date: November 1, 2001
    Inventors: Fuzheng Zhou, Chung-Po Huang, Liyue Mu