METHOD OF PRODUCING POLARIZATION CONVERTER Russian patent published in 2024 - IPC G02B5/30 C03C3/87 

FIELD: optical material science.

SUBSTANCE: invention relates to optical material science, to polarization converters and phase plates. Method of producing polarization converter consists in direct laser recording of anisotropic structures in glass, it includes focusing femtosecond laser pulses into a glass volume and moving the focused beam relative to the dielectric along a given trajectory, synchronized with controlling the polarization of the recording laser beam to form the required geometry and spatial orientation of the slow axis of birefringence of the converter. Transparent dielectric used is porous glass obtained from glass of composition, wt.%: 66 SiO₂; 26.7 B₂O₃; 6.8 Na₂O; 0.5 As₂O₃ by guiding a metastable liquation structure at temperature of 520 °C for 72 hours, followed by etching in 3-molar solution of hydrochloric acid at temperature of 50 °C, and the laser generates pulses with a wavelength of the near infrared range with duration of 180÷300 fs, with a repetition frequency of 1-200 kHz, energy of 400-2,500 nJ when moving a laser beam focused by a lens with a numerical aperture of 0.1-0.3, at rate of 0.1-100 mm/s, with a pitch between recording tracks forming a polarization converter, 1 mcm.

EFFECT: high rate of recording phase plates or polarization converters.

1 cl, 5 dwg