Nematic liquid crystals for optical shutters: A concept

Nonmechanical shutter utilizes nematic crystals to attenuate illumination, thus protecting light-sensitive devices such as vidicon or image orthicon tubes and phototubes. Opacity of liquid crystals is controlled by photosensor

Aerospace medicine and biology: A continuing bibliography with indexes (supplement 346)

This bibliography lists 134 reports, articles and other documents introduced into the NASA Scientific and Technical Information System during Jan. 1991. Subject coverage includes: aerospace medicine and psychology, life support systems and controlled environments, safety equipment, exobiology and extraterrestrial life, and flight crew behavior and performance

Resonance tunneling of polaritons in 1-D chain with a single defect

We consider propagation of coupled waves (polaritons) formed by a scalar electromagnetic wave and excitations of a finite one dimensional chain of dipoles. It is shown that a microscopic defect (an impurity dipole) embedded in the chain causes resonance tunneling of the electromagnetic wave with the frequency within the forbidden band between two polariton branches. We demonstrate that resonance tunneling occurs due to local polariton states caused by the defect.Comment: 11 pages, 9 figures (PS-format), RevTe