Portable astronomical observation system based on large-aperture concentric-ring metalens.

Area of Science:

• Optics and Photonics
• Materials Science

Background:

• Traditional lenses are bulky and heavy, limiting applications.
• Large-aperture metalenses face high design and fabrication costs.
• Existing metalens designs struggle with macro-scale imaging demands.

Purpose of the Study:

• To develop a cost-effective and efficient design method for large-aperture metalenses.
• To address the contradiction between increasing demand for large metalenses and rising costs.
• To enable macro-scale optical imaging applications, including astronomical observation.

Main Methods:

• Proposed a novel design method for fixed-height concentric-ring metalenses.
• Constructed a subwavelength 2D building unit library based on topological structures.
• Assembled the metalens cross-section, reducing computational resources by orders of magnitude compared to global optimization.

Main Results:

• Developed a concentric-ring metalens (46.8 mm diameter, 632.8 nm wavelength).
• Constructed a quasi-telecentric telescope system achieving high-resolution detection within a 20° field of view.
• Demonstrated weak polarization dependence and narrowband adaptability with excellent imaging results.

Conclusions:

• The novel design method significantly reduces computational resources and time for large metalenses.
• The developed metalens-based telescope system is simple, lightweight, and provides high-resolution imaging.
• This work promotes the application of large-diameter metalenses in astronomical observation and other fields.