A Design Method of Diffraction Structure Based on Metasurface for High-Resolution Spectroscopy

Area of Science:

• Optics and Photonics
• Metamaterials Science
• Diffractive Optics

Background:

• Metasurfaces enable novel light manipulation functionalities.
• Existing meta-lens designs face limitations in working bandwidth and resolution.
• Simultaneous light splitting and focusing is a key challenge in optical system design.

Purpose of the Study:

• To propose a new design method for metasurface-based diffraction structures.
• To achieve simultaneous light splitting and focusing with enhanced performance.
• To explore applications in high-resolution, wide-band spectrometer systems.

Main Methods:

• Establishing a light field calculation model based on Fresnel diffraction.
• Calculating the transmittance function of the metasurface structure.
• Deriving the spectrum resolution equation and determining structural parameters.

Main Results:

• The proposed metasurface design demonstrates a broader working bandwidth.
• Enhanced higher resolution is achieved compared to off-axis meta-lenses.
• The design shows potential for ultra-compact spectrometer systems.

Conclusions:

• The developed metasurface design method effectively enables simultaneous light splitting and focusing.
• The proposed structure offers superior performance metrics over conventional meta-lenses.
• This approach paves the way for advanced, miniaturized spectroscopic instruments.