High-Sensitivity Birefringence Mapping Using Near-Circularly Polarized Light

I will describe several techniques for mapping a two-dimensional birefringence distribution, which can be classified according to the optical schemes and principles of work:

  • Illumination geometry (transmitted light/reflected light)
  • Image acquisition (sequential acquisition/simultaneous acquisition)
  • Polarization control (electrically controlled variable retardance/mechanical rotation).

This classification facilitates a comparative analysis of the capabilities and limitations in these methods for birefringence characterization. 
Polychromatic polarizing microscopy (PPM) provides unique capabilities to alternative methods. It leverages vector interference to generate vivid, full-spectrum colors at extremely low retardances, down to < 10 nm. PPM is a significant departure from conventional polarizing microscopes that rely on Newton interference, which requires retardances above 400 nm for color formation. Furthermore, PPM's color output directly reflects the orientation of the birefringent material, a feature absent in conventional microscopy where color is solely determined by retardance.

Joint seminar of ILEE & NISM!

Le séminaire est accessible à des personnes externes également, pas besoin de s'inscrire.