Compact planar optical device significantly enhances dark-field microscopy capabilities: super-resolution beyond diffraction limit

https://phys.org/news/2025-03-compact-optical-device-super-resolution.html

"overcomes complex, bulky setups precisely aligned... planar photonic device integrates scattering layer, 1D photonic crystal, metallic film generating dark-field speckle patterns acting momentum-space filter to produce hollow speckle pattern cones providing illumination... easily integrated into conventional microscopes... high-contrast imaging with 1.55X improvement in spatial resolution... resolved adjacent beads with beyond diffraction limit 340 nm center-to-center distance... supports optical surface imaging"