Optical Fibers for Communication

A new transmission medium is about to emerge as a competitor to copper media in many communications applications. It is the optical fiber, 100 μm or so in diameter and made principally of silica, one of the most abundant materials on earth. When suitably engineered, optical-fiber cables may be used in a variety of applications where twisted copper- wire pairs, coaxial cables, and metallic waveguides are now used for the transmission of information; these applications range from short data links and equipment interconnections within a building to long telecommunications trunk circuits connecting switching offices within a city or between cities.

by Tingye Li

Holography: The Second Decade

Here we outline the background of some of these recent developments in display holography. Because the discussion is limited to matters of which the author has fairly direct knowledge, some interesting reports must await confirmation, and others may have been overlooked.

by Stephen A. Benton

Coherent Optical Radar

Despite these early beginnings, the use of light for range measurements has been limited. One of the few applications that comes to mind is the measurement of cloud heights by using a pulsed flashlamp. All of which brings us to the key word in our title, "coherent."

by R. H. Kingston

Museum of Holography

On December 8 of last year, science and art joined hands as Mayor Abraham Beame opened New York City's most modern museum, the Museum of Holography. Six hundred persons were on hand to view the inaugural exhibition, "Through the Looking Glass," a collection of twenty-four holograms by ten of the nation's prominent holographers. Represented in the collection were reflection holograms, dichromate holograms, white-light transmission holograms, and white-light integral holograms (holographic movies).

by Harriet Casdin-Silver