| 摘要 |
<p>1. A method for focusing a lens when processing a workpiece using a laser beam, a lens held in a lens frame being moved along the optical axis by means of a drive motor, characterised in that the lens (4) is adjusted, by means of at least two identically moved spindle bolts (8.1 to 8.3) fixed on the lens frame (5), in the direction of the optical axis into the situation producing the desired focal spot position (39), by rotation of cogwheels (12.1 to 12.3) surrounding the spindle bolts (8.1 to 8.3) and provided with an inner thread all having the same number of teeth, in a cavity (35) of a central body (31), the cogwheels (12.1 to 12.3) being driven by the drive motor (25) with a drive cogwheel (12.4) via a toothed belt (23), and the whole drive unit (12.1 to 12.3, 12.4; 23, 25) being borne by a carrying plate (15) ; and in that the lens frame (5) is cooled by at least one inner cooling duct (6).</p> |
