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Lasers: The First 25 Years
Since the earliest days of the utilization of the electromagnetic spectrum, there has been a steady drive toward the production and use of coherent electromagnetic energy of higher and higher frequency. This tendency resulted partly from the realization that an increase in transmitted information, directivity, and efficiency were available with increasing carrier frequency and partly as a result of crowding and interference between existing frequency bands.
Publish Date: 01 October 1985