Basic Research on Seabed Visualization Technology Applying UV-Laser

Abstract Recently, in order to efficiently explore seabed resources using underwater vehicles, researches on effective technologies to visualize the seabed have been conducted. Underwater laser scanners have been proposed as one of effective methods that combine good measurement range and accuracy. An underwater vehicle equipped with an underwater laser scanner emits a laser and detects the reflection on the seabed to visualize the seabed topography with high precision. The characteristics of seabed reflection is difference depending on laser wavelength. Conventionally, visible lasers of blue to green wavelengths, which have good underwater propagation properties, have been used. Currently, we are currently working on a new underwater laser scanner that applies an invisible ultraviolet (UV) laser. It is expected that by understanding the underwater propagation properties of invisible laser and effectively detecting the laser reflections from the seabed, some unique state quantities of the seabed might be extracted. The new underwater laser scanner that uses UV wavelengths laser has been developing and its basic performance and effectiveness were verified in an actual deep seabed environment.