Abstract

The physical properties of the ocean place certain limits on the optical wavelengths which can be used in undersea communications. The so-called Jerlov minimum¹ is between 460 and 480 nm. Laser transmitters operating out of this range suffer increasing attenuation at greater and lesser wavelengths. For example, a laser transmitting at the Jerlov minimum in Class I water would be attenuated a factor of fifty less than a laser transmitting at 505 nm at a depth of 1000 feet. The diagnostics used to determine water class usually give indications of transmissivity for near-surface layers². In fact, sea water may be thought of a being Class I water at all depths, with the exception of phytoplankton layers near the surface³.

© 1983 Optical Society of America