Spiral phase plate with adjustable parameters

Abstract

The invention relates to a spiral phase plate with adjustable parameters, characterized in that a solid spiral phase plate is fixed on the end surface at one side of a transparent container while the spiral surface faces inwards; the container is filled with refraction rate matching liquid to form a liquid spiral phase plate complementary to the solid spiral phase plate; and the refraction rate difference between the solid spiral phase plate and the matching liquid and the topological charge value m of an optical vortex meets a relational expression in the specification. On the premise that the advantages of high conversion rate, simple light path structure, and the like of a traditional spiral phase plate are guaranteed, the spiral phase plate with the adjustable parameters, which is provided by the invention, is beneficial to simplification of the manufacture process, realization of adjustable parameters and flexible control of the topological charge value for generating the opticalvortex. In addition, the spiral phase plate provided by the invention has no requirement for the wavelength of a light source and has favorable suitability.

Description

technical field [0001] The invention relates to a helical phase plate with adjustable parameters, which is used to modulate any wavelength monochromatic light source to generate an optical vortex with any topological charge, and is regarded as a helical phase plate with adjustable parameters. Background technique [0002] Due to its unique phase structure and topological properties, optical vortex has attracted extensive attention in the fields of basic research and applied research in recent decades. In the field of optics, if there is a phase singularity in the center of the optical wave field, and the phase continuously changes spirally around the singularity, the optical wavefront will rotate in a spiral manner in the direction of propagation, forming a spiral wavefront, which is very similar to fluid The vortex phenomenon in, so this kind of light wave is called "optical vortices" (OpticalVortices). The central intensity of this type of beam is strictly zero due to des...

AI Technical Summary

Problems solved by technology

However, a major problem with using computational holography is the presence of multiple orders of diffraction

Although optical vortices with different topological charges can be generated simultaneously, the diffraction efficiency of each order of vortex diffracted light is not high enough

In recent years, people have done in-depth research on the generation method of this vortex theoretically and experimentally, but the highest diffraction efficiency obtained is only 27.5%.

[0004] In addition, there are other generation methods, such as hollow waveguide method, rotating mirror optical parametric oscillation method, etc., but these methods are not as good as the above-mentioned methods in terms of scope of application and application range.

In short, the existing spiral phase mask has high processing precision requirements, and the spiral phase mask has a one-to-one correspondence with the optical wavelength, and its topological charge cannot be adjusted.

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