Abstract: A method of decreasing the penetration depth of radiation provided to an interface, such as a surface, or a predetermined volume in a polyethylene (PE) element, where the PE element has a scattering coefficient larger than one tenth of an absorption coefficient thereof so that the radiation not absorbed at the interface or in the volume but transmitted further into the PE element is at least partly reflected toward the interface/volume. The radiation intensity is higher in the volume and the absorption coefficient may be reduced while retaining the total absorption in the volume.

Abstract: An ostomy body side mounting wafer and a method of preparing the ostomy body side mounting wafer, where the wafer is assembled from two parts using laser welding. The laser light is provided through one of the parts having a low or lower absorption of the laser light. The other part has a higher absorption of the laser light, whereby the interface between the two parts is heated at the welding zone(s) of the laser light. In this manner, an assembly is obtained independently of the thicknesses of the materials and even close to openings or other edges.

Abstract: A method of decreasing the penetration depth of radiation provided to an interface, such as a surface, or a predetermined volume in a polyethylene element, where the PE element has a scattering coefficient larger than one tenth of an absorption coefficient thereof so that the radiation not absorbed at the interface or in the volume but transmitted further into the PE element is at least partly reflected toward the interface/volume. The radiation intensity is higher in the volume and the absorption coefficient may be reduced while retaining the total absorption in the volume. This may be used for all known techniques where radiation is desired absorbed, such as in welding, surface preparation, polymer chemistry, the activation of photo activatable substances etc.