15 November 2002
Vol 298, Issue 5597

About The Cover

Cover image expansion

COVER A crystal with 41 holographic filters. Each filter selects one wavelength channel in the fiber communication system at near-infrared wavelengths. When illuminated with white light, each filter diffracts a slightly different spectral band, creating a blue-to-green color gradient. Optical storage is one example of coherence manipulation highlighted in the special section in this issue. 1353 [Photo: Chris Moser and Demetri Psaltis]