The invention relates to a vapor barrier for use in cthe thermal insulation of buildings which can be used, in particular, for thermal insulation procedures in new buildings or in the renovation of old buildings. The device further includes a user interface comprising a plurality of buttons for operating the device and at least one securing element coupled to the body. Together with the substrate, the scintillator is covered with a polyparaxylylene film. In one embodiment, the database is remote from the device, wherein verification is performed over a network connecting a database server containing the database with the device. Fluidic optical devices may be used in applications including optical switching, optical filtering, or optical processing.