Metalens scans entire eye in 3D with 1.2mm depth

Researchers have developed a metalens-based photoacoustic microscopy system capable of 1.2 mm axial coverage, a substantial increase over the shallow depth of focus limiting current in-vivo tissue imaging. The new system uses a silicon nitride nanostructured metalens to switch between two focal modes at visible wavelengths, requiring only 0.87 V and 1.03 V and responding in 250 ms without mechanical parts. Demonstrated through high-resolution imaging of neovascularization in rat eyes with chemically induced corneal burns, the compact system provides "building blocks for future high-resolution volumetric imaging with an improved signal-to-noise ratio." Achieving 1.2 mm axial coverage represents an advance in vivo photoacoustic imaging, enhancing…