Grating- and checkerboard-based zone plates as an optical array generator with a favorable beam shape

Area of Science:

• Optics and Photonics
• Diffractive Optics
• Nanophotonics

Background:

• Periodic and quasi-periodic structures are fundamental in optics for controlling light.
• Fresnel zone plates and gratings are established optical elements with diverse applications.
• Developing efficient array generators is crucial for advanced optical systems.

Purpose of the Study:

• To propose novel array generator elements by combining gratings and Fresnel zone plates.
• To investigate the influence of grating structure on diffraction performance.
• To demonstrate the generation of various optical patterns, such as vortex and spot arrays.

Main Methods:

• Theoretical modeling and simulation of combined grating and zone plate structures.
• Analysis of diffraction performance based on grating periodicity and structure.
• Experimental validation of simulated results for array generator elements.

Main Results:

• The diffraction performance of array generators is significantly dependent on the grating structure.
• Replacing a standard grating with a checkerboard structure enhances diffraction efficiency.
• Different zone plate types (spiral, cross) yield distinct array patterns (vortices, spots) with improved performance.

Conclusions:

• The proposed combination of gratings and Fresnel zone plates offers a versatile platform for novel array generators.
• Optimizing grating structure is key to enhancing the performance of these diffractive elements.
• The method is generalizable to various zone plate designs, enabling tailored optical beam generation.