ACOUSTO-OPTIC FILTER WITHOUT RADIO FREQUENCY SHIFT OF FILTERED RADIATION AND LASER DEVICES WITH ITS APPLICATION Russian patent published in 2021 - IPC G02F1/11 

FIELD: laser technology.

SUBSTANCE: invention relates to laser technology, applied optics, acousto-optics, spectroscopy, measuring technology. In the noncollinear acousto-optic filter for uniaxial birefringent crystal of arbitrarily polarized radiation with a wavelength of λ with two orthogonal plane-polarized once diffracted on ultrasonic wave with a frequency of ƒ at angles α₁ and α₂ in the air relative to the normal to the rear of the optical crystal face filter light e- and o- beams at the exit behind the rear output optical crystal face filter on the way of these diffracted light beams, an optical device for their return at the same angles α₁ and α₂ back to the crystal filter is installed. Each beam returns along the path of another beam with opposite polarization. The specified optical device has the form of either a mirror system or a retroprism with complete internal reflections made of an optically transparent material in the form of optical glass or a crystal of cubic symmetry, and both mirrors and retroprisms are used in conjugation with a phase element rotating the plane of polarization by 90°.

EFFECT: invention provides simplification of the filter design, the possibility of directly embedding an anisotropic acousto-optic filter into a laser resonator with an isotropic fiber light guide without the use of external polarization devices, reducing optical losses due to the absence of an external polarization divider, the absence of a radio frequency shift of the output light beam.

3 cl, 7 dwg