| 摘要 |
<p>The device comprises a structure (1) supporting a light beam source (2), a beam guide and a camera assembly (3), the light beam source (2) being arranged to direct an outgoing beam of light (I) into the beam guide which projects the outgoing beam (P) onto a target surface to sweep the beam around an endless path (E) on the target surface, scans synchronously around the endless path (E) to receive light returning from the portion of the path (E) illuminated by the outgoing beam (P), and directs the returning light (P) onto a light sensor (12) provided in the camera assembly (3); the beam guide comprising a rotatable wedge prism (5) arranged such that the outgoing beam (2) is transmitted through relatively inclined surfaces (9, 10) of a projecting element of the prism (5) as it is rotated to direct the beam (P) to sweep around the endless path (E) and the light returning from the portion of the path illuminated by the beam (P) is received through relatively inclined surfaces (9, 10) of a receiving element of the prism (5) as it is rotated to direct the returning light (P) onto the light sensor (12). The position of the image formed on the sensor (12) is indicative of the range of the illuminated portion of the target surface and, from a knowledge of the position of the scanning beam, its three-dimensional position can be determined. An image of the sensed topology can thus be built up as the target surface is scanned.</p> |
