Three-level transmittance 2D grating with reduced spectrum and its self-imaging

Area of Science:

• Optics and Photonics
• Diffraction Gratings
• Holography

Background:

• Traditional methods for creating 2D diffraction structures can be complex.
• Additive superimposition of gratings offers a potential alternative for novel optical element fabrication.

Purpose of the Study:

• To propose and demonstrate a simple method for generating 2D binary amplitude structures.
• To investigate the properties of these structures in the Fresnel diffraction field.

Main Methods:

• Software generation of three binary amplitude gratings: crossed Ronchi, checkerboard, and 1D Ronchi.
• Computer processing involving multiplication of checkerboard and 1D gratings, followed by addition to the crossed grating.
• Analysis using spectrum domain, simulations, and experimental verification in the Fresnel diffraction field.

Main Results:

• Successful generation of a 3-level transmittance (0, 0.5, 1) hybrid diffraction structure.
• The zero diffraction order contains crossed spectra of additively superimposed 1D gratings.
• Demonstration of unique Fresnel field properties distinct from multiplicative superimposition gratings.

Conclusions:

• The proposed additive superimposition method provides a simple route to novel 2D periodic structures.
• The generated hybrid diffraction structures exhibit unique Talbot effect properties.
• This work presents the first reported study on the Fresnel field properties of additively superimposed 2D gratings.