How do super resolution techniques overcome the challenges of diffraction limit?

Super resolution techniques overcome the diffraction limit of light through several ways. One way is by increasing the intensity of light in the annulus region. By doing this, it causes a broader area of saturation to form a smaller excitation PSF that is smaller in diameter than the diffraction limit of 200 nm. This allows for the light to be focused more precisely and for images to be more detailed. Another way to overcome the diffraction limit of light is through surface plasmons. Surface plasmons are electromagnetic waves which travel across the interface between a metal and a dielectric material. As these waves hit the metal-insulator-metal interface, it leads to the excitation of surface plasmon polaritons (SPPs). Surface plasmons are able to induce alterations of light at a subwavelength scale for use in various applications.