摘要 |
<p>An apparatus for determining the shape of an object such as an exhaust pipe comprises a carriage (11) which carries a scanning unit (10) and is movable by a motor (22) along a base (12) having supports (17) for the object. The scanning unit comprises two laser units (37) the light beams of which are directed by rotating mirrors (42) towards two parabolic mirrors (35), the beams being reflected by the latter so as to traverse the object at right angles to one another and in a common plane at right angles to the movement of the carriage. The beams are interrupted by the object, and light-responsive means (38) detect such interruption to determine the shape of the object. In a modification, the apparatus has two or three rotating laser units (50). </p> |