| 摘要 |
The device has an optical head (26) with rotary unit (30) having a mirror (34) with a plane surface and another mirror (38) deviating an incident light beam (28) in a direction of a thin transparent layer (2). The head moves rotatively at a speed permitting a light beam projected on the layer to follow rectilinear pattern on certain distance, where the speed is synchronized with a moving speed of the layer. |
