Fig. 1. Schematic layout of the experimental setup for studying the total reflection of a femtosecond filament at the air-glass surface. M1 and M2 are silver-coated mirrors.

Fig. 2. Images of the propagation trajectory of the filamentary laser beams inside the BK7 glass with the incident laser pulse energy set to be (a) 0.09 mJ and (b) 0.87 mJ. It should be pointed out that the hot tops in Figs. 2(a) and 2(b) are caused by the scattered light, which cannot totally blocked in the measurement. (c) and (d) are the corresponding far-field spatial profiles of the filamentary laser beams after reflection at the air-glass surface.

Fig. 3. Far-field spatial profile of the transmitted laser beam through the air-glass surface with the incident laser pulse energy set to be (a) 0.09 and (b) 0.87 mJ.

Fig. 4. Dependencies of the pulse energy of the reflective beam (the black solid line of squares), the total energy ratio, and the core energy ratio on the pulse energy of the incident laser beam.