Abstract: Experimental research on dynamic process of bubble generation and trapping induced by self-focused femto-second laser pulses using fast-frame video microscopy and high frequency ultrasound imaging.Experimental results indicate that after the appearance of a series of microbubbles around the laser focus, a single microbubble generated via laser induced optical breakdown(LIOB)could be trapped stably by the self-focused SF femtosecond laser in water.The trapped bubble could be operated in the non-contact and three-dimensional way afterwards.Furthermore, the spatiotemporal and mechanical characteristics of bubble generation and trapping by self-focused femtosecond laser pulses at multiple locations along the laser beam were discussed.The experimental results can supply with new technological supports for the application of microbubble in targeted therapy at molecular level.

Key words: femto-second laser pulses, laser-induced optical breakdown(LIOB), microbubble, fast-frame video microscopy, high frequency ultrasound imaging