Abstract: The embodiments described herein provide improved techniques for laser welding. These techniques can provide improved weld strength while reducing the potential for damage at the welding surface. In general, the techniques use a mask to selectively block a portion of the laser beam during welding. Specifically, the mask is made to include at least one laser light blocking feature and at least one laser light passing feature. The mask is positioned to be in contact with the plastic bodies that are to be welded together, with the laser light blocking feature and laser light passing feature proximate to the area that is to be welded. Then during welding the laser beam is operated to simultaneously impact the laser light blocking feature and pass through the laser light passing feature.