Reflection confocal nanoscopy using a super-oscillatory lens

Area of Science:

• Optics
• Microscopy
• Nanotechnology

Background:

• Superoscillatory lenses (SOLs) generate sub-diffraction limited hotspots, promising for advanced imaging.
• Previous applications of SOLs were hindered by their inherent poor imaging properties and sidelobe illumination.
• Confocal reflection microscopy offers a potential setup to mitigate SOL imaging limitations by excluding the lens from the detection path.

Purpose of the Study:

• To evaluate the resolution capabilities of SOLs within a confocal reflection microscopy setup.
• To investigate the impact of SOL sidelobe illumination on imaging performance for various object sizes.

Main Methods:

• A confocal reflection microscopy system was designed, incorporating a SOL in the illumination path.
• The imaging resolution of the SOL was assessed using test objects of varying dimensions.
• The SOL was excluded from the detection pathway to circumvent its poor imaging characteristics.

Main Results:

• The SOL successfully produced a sub-diffraction hotspot, demonstrating its potential for high-resolution imaging.
• Sidelobe illumination from the SOL significantly degraded imaging quality for extended objects.
• The resolution enhancement of the SOL was limited in the presence of sidelobes, particularly for larger targets.

Conclusions:

• Confocal reflection setups can mitigate some imaging drawbacks of SOLs by isolating them in the illumination path.
• Sidelobe illumination remains a critical challenge, restricting the practical application of SOLs for imaging extended objects.
• Further advancements are needed to suppress sidelobes for broader utility of SOLs in super-resolution microscopy.