Controllable design of super-oscillatory planar lenses for sub-diffraction-limit optical needles

Area of Science:

• Optics and Photonics
• Nanotechnology

Background:

• Sub-diffraction-limit optical needles are crucial for advanced applications like super-resolution imaging and nanofabrication.
• Creating high-quality optical needles requires precise control over various optical parameters.

Purpose of the Study:

• To present a controllable design for super-oscillatory planar lenses.
• To achieve sub-diffraction-limit optical needles with tunable focal length and depth of focus (DOF).

Main Methods:

• Development of a multi-objective and multi-constraint optimization model.
• Implementation of a self-designed optimization procedure using Matlab, incorporating the genetic algorithm (GA) and fast Hankel transform algorithm.
• Validation through numerical simulations and theoretical calculations using the Rayleigh-Sommerfeld integral.

Main Results:

• Demonstration of accurate control over optical needle properties.
• Successful creation of sub-diffraction-limit optical needles with tunable characteristics.
• Validation of simulation results through theoretical calculations.

Conclusions:

• The proposed super-oscillatory planar lens design offers a controllable method for generating optical needles.
• The optimized optical needles have potential applications in optical nanofabrication, super-resolution imaging, particle acceleration, and optical data storage.