Enhancing laser welding abilities of 3- to 7-axis 795, 430 BD, and 430 Vera laser processing systems, SmartShield™ lens and nozzle assemblies protect against excessive oxidation in weld area. High-velocity gas barrier prevents metal sparks from weld zone contaminating protective lens cover slide, and cross-jet does not contaminate or otherwise interfere with welding shield gas. Focusing lens/shield gas assemblies can be changed to vary focused spot size or from welding to cutting or drilling.