A device for generating cylindrical vector polarized light beams by a polarizing prism

Abstract

The present invention provides a device for generating a cylindrical vector polarized light beam based on polarizing prisms. The device for generating the cylindrical vector polarized light beam based on the polarizing prisms is characterized by comprising an adjustable beam expanding lens, common base biconical transmitting mirrors, a concave conical transmitting mirror, double refraction crystal common base double cones, and a vortex type phase plate, wherein an incident light beam is shaped by the adjustable beam expanding lens and then is emitted out by the common base biconical transmitting mirrors to generate a hollow annular light beam; the hollow annular light beam is radiated from the air to the concave conical transmitting mirror and then is separated into the ordinary light and the extraordinary light in the double refraction crystal common base double cones; the vortex type phase plate is an optical component for modulating the phase of the light beam; the hollow annular light beam passes the concave conical transmitting mirror and carries out double refraction in the double refraction crystal common base double cones, so that the hollow annular light beam is emitted out from the double refraction crystal common base double cones to generate a circular ring-shaped cylindrical column vector beam with a vortex phase, and then the circular ring-shaped cylindrical column vector beam passes the vortex type phase plate to generate a cylindrical vector light beam. The device for generating the cylindrical vector polarized light beam based on the polarizing prisms has the characteristics of simple and stable structure, high extinction ratio and easy processing, and the generated cylindrical vector light beam possesses a high degree of polarization.

Description

technical field [0001] The invention belongs to the field of optical technology, and relates to a cylindrical vector polarized light beam generating device, in particular to a polarizing prism generating cylindrical vector polarized light beam device. It is mainly used in optical microscopy, laser micromachining, optical micromanipulation, optical information storage, lithography and other fields. Background technique [0002] Cylindrical vector beams have been applied to optical information storage, optical microscopic imaging, lithography, laser processing, particle control, lithography and other fields due to their special focusing properties and propagation characteristics of high numerical aperture objective lenses. . For example, after the phase and amplitude modulation of the wavefront, the cylindrical vector beam is focused by a high numerical aperture objective lens, and multi-focal points along the optical axis that can be used for particle transmission are genera...

AI Technical Summary

Problems solved by technology

In the previous technology, the cylindrical vector beam was generated by adding mode extraction elements in the laser resonator, which not only required a special level of technology, but also was not conducive to the transformation of real commercial lasers. large-scale use

On optics letters, researchers use polarizing films to convert circularly polarized light into cylindrical vector beams [see the literature "Production of radially and azimuthally polarized polychromatic beams," Opt. Lett.31(23), 3405-3407(2006).] , but there are several deficiencies in this method: (1) Use a polarizing film to convert radially propagating circularly polarized light into radially propagating linearly polarized light, so that the quality of the beam depends on the quality of the polarizing film, and if you want to It is difficult to obtain a high-purity cylindrical vector beam; (2) because the polarizing film is difficult to fix, it is not conducive to processing the whole device into a whole, and the mechanical stability of the polarizing film is not good, which further limits the practical application of this method

There is also a cylindrical vector beam generation method published abroad, see US Patent US7599069B2, patent name: Vector beam generator using a passively phase stable optical interferometer, this method has a complex structure, uses the principle of optical coherence to lead to high requirements for system positioning, and requires diffractive optical elements Not easy to obtain, low degree of polarization of vector beams, etc.

Images