A single-canister underwater stereocamera system with a distance
measurement function. In the camera system, a camera drive unit, holding
two cameras on its camera base, is set in a parallel space defined between
two support plates, and is operable by a motor unit, thus being movable
along with the two cameras to the front or back. A lens drive unit,
holding two lenses on two lens bases, is set in the parallel space to be
operable by the motor unit so as to laterally move the two lenses to the
left or right under the guide of a linear guide bearing. The motor unit
controls the focus length of each of the two cameras and the moving
distance of the two lenses at the same time. In the camera system, the
actual distance of an underwater target object from the system is measured
by sensing a rotated position of the encoder of the motor unit, taking
advantage of the fact that the actual distance of the target object has a
functional relation of 1:1 with the focus length of each of the cameras.
This camera system measures the actual distance of the target object while
compensating for the refraction errors of light beams passing through both
the window and water. The camera system is also encased within a
waterproof and pressure-proof cylindrical canister having a transparent
window at its front end wall. This camera system is thus effectively
usable in deep sea.
