Abstract:
Through discussion on the damage mechanism of wide-band optical transparent dielectrics and comparison of the damage levels of wideband optical transparent dielectrics ablated by ultra-short laser pulses and long laser pulses, a powerful tool applicable to processing wideband optical transparent dielectrics with ultrashort laser pulse is obtained. When laser pulse with wavelength of 800nm and pulse time of 150fs is focused into the inside of transparent dielectrics (K9 glasses and ZK6 glasses) with different band widths, the gratings with different constants can be made. The far-field relative diffraction efficiency and the diffraction efficiency of the grating were measured under the vertical illumination of He-Ne CW laser at 635nm.