Optical function of the finite-thickness corrugated pellicle of Euglenoids

MARINA INCHAUSSANDAGUE; DIANA C. SKIGIN; ANDRÉS E. DOLINKO

APPLIED OPTICS

OPTICAL SOC AMER

Lugar: Washington; Año: 2017

0003-6935

Motivated by the differentiated behaviour under UV radiation treatments observed between species of Euglenoids that exhibit a corrugated profile of their pellicle and those that do not, we investigate their electromagnetic response in the UV and visible ranges of the spectrum. These microorganisms are covered by a typical surface pellicle formed by S-shaped overlapping bands which resemble a diffraction grating. Then, we investigate the role played by this structure in the protection of the cell against UV radiation. By considering the pellicle as a periodically corrugated film of finite thickness, we applied the C-method to compute the reflectance spectra. The far field results revealed very high Q reflectance peaks in the UV region for all the illumination conditions investigated. The resonant behaviour responsible for this enhancement has also been confirmed by near field computations performed by a photonic simulation method. These results confirm that the Euglenoids corrugated pellicle shields the cell from harmful UV radiation and open up new possibilities for the design of highly UV reflective surfaces.