Adaptive optics for direct laser writing with plasma emission aberration sensing

Area of Science:

• Optics and Photonics
• Materials Science
• Laser Physics

Background:

• Refractive index mismatch causes aberrations, degrading focal spot quality in direct laser write applications.
• Adaptive optics offer a potential solution for aberration correction if a reliable feedback signal is available.
• Ultrafast laser focusing in dielectrics can induce plasma, emitting supercontinuum radiation.

Purpose of the Study:

• To investigate the use of plasma-generated supercontinuum as a feedback signal for aberration correction.
• To demonstrate aberration correction in direct laser write systems using adaptive optics.
• To fabricate nanostructures with improved precision using the corrected optical system.

Main Methods:

• Generating plasma by focusing an ultrafast laser into a transparent dielectric material.
• Utilizing the emitted supercontinuum as a diagnostic signal to measure optical aberrations.
• Implementing a closed-loop adaptive optics system with a spatial light modulator for aberration correction.

Main Results:

• Successfully measured optical aberrations using the plasma supercontinuum.
• Demonstrated effective aberration correction with the adaptive optics system.
• Fabricated nanostructures with enhanced precision due to improved focal spot quality.

Conclusions:

• Plasma-generated supercontinuum is a viable feedback signal for adaptive optics in direct laser writing.
• Adaptive optics can significantly improve focal spot quality and enable precise nanostructure fabrication.
• This approach offers a pathway for high-resolution laser processing in materials.