Total absorption of light by a sinusoidal grating near grazing incidence

Abstract

A heretofore unknown total absorption phenomenon on a diffraction grating has been demonstrated both theoretically and experimentally. It occurs only in a series of six special conditions, namely, groove shape, angle of incidence, groove frequency, depth modulation, polarization, and metal surface. None of the classical explanations for grating anomalous behavior seems to correspond to this case.

Brewster effects for deep metallic gratings

“…Although at a first glance the two cases seem to be quite different, the physical origin for the strong absorption peaks is the excitation of surface waves. We demonstrated recently that total absorption of light may occur also in the presence of two diffracted orders, in grazing incidence, 4 ' 5 but this case is not connected directly with the excitation of surface waves.…”

Photoluminescent Distinction among Plant Life Forms Using Phosphate Buffered Saline Extract Solutions

“…The decreased signal intensities shown at ;515 nm for all spectra (Figs. 2-5) can be attributed to the absorption of light by surface plasmons associated with the surface of the holographic grating used for these measurements (i.e., the Wood's grating anomaly [30][31][32] ). Interestingly, a similar spectral feature was reported by Chappelle et al 12 for spectra from species of corn and soy beans after correcting for wavelength-dependent detection variances.…”

“…Unfortunately, the use of a holographic grating resulted in the observation of the Wood's grating anomaly. [30][31][32] This was manifested as an apparent local minimum in all spectra at ;515 nm. Because the purpose of this study was not to identify the molecular species responsible for each feature of the recorded spectra but to use the entire resulting spectral signatures to distinguish among plant species, further correction for this anomalous feature was not undertaken.…”

Differentiating Among Plant Spectra by Combining pH Dependent Photoluminescence Spectroscopy with Multi-Way Principal Component Analysis (MPCA)

“…Use of the holographic grating resulted in the Wood's grating anomaly [34][35][36] being observed and it was left uncorrected. It manifested itself as an apparent local minimum in all spectra at ~515 nm.…”