The conditions for the formation of microdomains with polarization-dependent birefringence by a femtosecond laser beam in sodium-borate glasses with different Na₂O content were determined. The dependences of the phase shift in the light passing through the birefringent zones on the parameters of laser exposure and on the chemical composition of the glass were determined. It is shown that an increase in the Na₂O content leads to a decrease in the minimum number of pulses required to form zones with polarization-dependent birefringence and under certain conditions to the formation of a special type of modification for which the slow axis of birefringence is parallel to the polarization plane of the laser beam.

确定了在不同Na ₂ O含量的硼酸钠玻璃中飞秒激光束形成具有偏振相关双折射的微区的条件。确定了通过双折射区的光的相移与激光曝光参数以及玻璃化学成分的关系。结果表明，Na ₂ O含量的增加导致形成具有偏振依赖性双折射的区域所需的最小脉冲数减少，并且在某些条件下会形成特殊类型的修饰，其慢轴为双折射平行于激光束的偏振面。