| 摘要 |
<p>Optical scanning apparatus comprising a source of light, a rotatable reflecting element having a plurality of reflective facets which are inclined to the axis of rotation, a beam expander for deriving a collimated beam of light from the source, this collimated beam being directed at the reflecting element in a direction parallel to its axis of rotation to impinge upon successive facets thereof as it is rotated. The apparatus also includes a support, which may be a system of rollers, for defining a position for a recording element having a surface that requires scanning, a projection lens for focussing the collimated beam as reflected by the reflecting element onto the surface of the recording element, a motor coupled to rotate the reflecting element, so that each facet in turn causes the focussed beam to scan across the surface in one direction, and a drive for moving the recording element substantially perpendicular to the direction of scanning, past said focussed beam.</p> |
