Miniature Two-Photon Microscopic Imaging Using Dielectric Metalens

Area of Science:

• Biomedical Engineering
• Neuroscience
• Optics

Background:

• Miniature two-photon microscopy is crucial for studying brain activity in freely moving animals.
• Current limitations include probe weight and restricted animal behavior.
• Dielectric metalenses offer a solution for compact, high-resolution optical systems.

Purpose of the Study:

• To design and fabricate a metalens-based probe for miniature two-photon microscopy.
• To reduce the weight and behavioral constraints of in vivo imaging probes.
• To demonstrate the feasibility of this technology for neuroscience research.

Main Methods:

• Fabrication of a high-aspect-ratio titanium dioxide metalens for 920 nm wavelength.
• Development of a meta-optic two-photon microscope probe weighing 1.36 g.
• In vivo two-photon imaging of mouse brain structures.

Main Results:

• Achieved a lateral resolution of 0.92 μm and an axial resolution of 18.08 μm.
• Successfully demonstrated in vivo imaging of mouse brain structures.
• The meta-optic probe is significantly lighter than conventional systems.

Conclusions:

• Flat dielectric metalenses are a promising technology for integrated miniature nonlinear microscopy.
• This approach enables high-performance endomicroscopy platforms for biomedical applications.
• The developed meta-optic probe advances in vivo neuroscience research capabilities.