Hybrid imprinting process to fabricate a multi-layer compound eye for multispectral imaging

Area of Science:

• Optics and Photonics
• Materials Science
• Microfabrication

Background:

• Fabricating multi-layer micro-optical structures on nonplanar substrates presents significant alignment challenges.
• Existing methods often lack the precision required for complex, integrated optical systems.

Purpose of the Study:

• To introduce a high-precision hybrid imprinting method for fabricating multi-layer micro-optical structures on nonplanar surfaces.
• To demonstrate the system's capability in multispectral imaging through the fabrication of an artificial compound eye (ACE).

Main Methods:

• Utilized a custom-built vacuum imprinting system with kinematic couplings for six-degrees-of-freedom stamp alignment.
• Achieved a cross-layer pattern registration precision of 400 nm on nonplanar substrates.
• Designed and fabricated a multi-layer ACE with optimized micro-lenses and integrated color filters for simultaneous multispectral imaging.

Main Results:

• Demonstrated high-precision fabrication of multi-layer micro-optical structures on nonplanar substrates.
• The fabricated ACE enabled simultaneous multispectral imaging, performing pattern detection across different frequency windows.
• Successful imaging experiments on color blindness test cards, space images, and tumor samples confirmed system capabilities.

Conclusions:

• The hybrid imprinting method offers a viable solution for precise fabrication of complex micro-optical systems on curved surfaces.
• The developed artificial compound eye system shows promise for advanced applications in frequency separation, information extraction, and medical diagnostics.