Study of wide-spectrum and high-resolution diffraction optical elements by stacks of binary phase gratings

Area of Science:

• Optics and Photonics
• Diffractive Optics
• Nanotechnology

Background:

• Traditional optical elements face limitations in resolution and spectral bandwidth.
• Diffraction gratings offer potential for miniaturization and novel optical functionalities.
• Multi-layer diffractive optical elements are an emerging area of research.

Purpose of the Study:

• To theoretically investigate wide-spectrum and high-resolution diffraction optical elements.
• To explore the use of stacked low-resolution binary phase gratings for advanced optical applications.
• To adapt existing algorithms for multi-scale diffractive optical element architectures.

Main Methods:

• Theoretical investigation of multi-layer diffractive optical elements.
• Remodeling the kinoform algorithm for multi-scale architectures.
• Numerical computations to analyze performance metrics.

Main Results:

• Increasing the number of grating layers enhances far-field image resolution.
• Stacked gratings demonstrate improved insensitivity to incident wavelength variations.
• A trade-off exists between resolution/wavelength insensitivity and reconstruction accuracy.

Conclusions:

• Stacking low-resolution gratings is a viable method for achieving high-resolution, wide-spectrum optical elements.
• The proposed multi-scale architecture offers advantages in terms of resolution and spectral performance.
• Further research is needed on increasing layer count, design efficiency, and manufacturing techniques for ultra-thin grating films.