Abstract
A laser ranging system that can observe the topographical structure of a volcano body has been developod. This system transmits laser toward a target and receive reflected light and render the three-dimensional topographical structure of a volcano body with approximately 30 cm accurecy. Although this accuracy is worse than that of a normal laser ranging system which uses a corner-cube reflector due to the jitter of reflected light caused by the inclination and unevenness of the target ground surface, it is still usefull to grasp a sign of a deformation of topographcal features where placement of reflector is very difficult. The system design and preliminay field test results obtained at Bandai volcano are reported.
