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Title: Ultrashort pulse high repetition rate laser system for biological tissue processing

Patent ·
OSTI ID:570385

A method and apparatus are disclosed for fast, efficient, precise and damage-free biological tissue removal using an ultrashort pulse duration laser system operating at high pulse repetition rates. The duration of each laser pulse is on the order of about 1 fs to less than 50 ps such that energy deposition is localized in a small depth and occurs before significant hydrodynamic motion and thermal conduction, leading to collateral damage, can take place. The depth of material removed per pulse is on the order of about 1 micrometer, and the minimal thermal and mechanical effects associated with this ablation method allows for high repetition rate operation, in the region 10 to over 1000 Hertz, which, in turn, achieves high material removal rates. The input laser energy per ablated volume of tissue is small, and the energy density required to ablate material decreases with decreasing pulse width. The ablation threshold and ablation rate are only weakly dependent on tissue type and condition, allowing for maximum flexibility of use in various biological tissue removal applications. The use of a chirped-pulse amplified Titanium-doped sapphire laser is disclosed as the source in one embodiment. 8 figs.

Research Organization:
Univ. of California (United States)
Sponsoring Organization:
USDOE, Washington, DC (United States); Office of Naval Research, Washington, DC (United States); National Insts. of Health, Bethesda, MD (United States)
DOE Contract Number:
FG03-91ER61227
Assignee:
Univ. of California, Oakland, CA (United States)
Patent Number(s):
US 5,720,894/A/
Application Number:
PAN: 8-584,522; CNN: Grant N0014-91-C-0134;Grant RR01192
OSTI ID:
570385
Resource Relation:
Other Information: PBD: 24 Feb 1998
Country of Publication:
United States
Language:
English

References (14)

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  • Neev, Joseph; Raney, Daniel; Whalen, William E.
  • Optics, Electro-Optics, and Laser Applications in Science and Engineering, SPIE Proceedings https://doi.org/10.1117/12.44100
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