A device for controlling light emissions and a method for fabricating the device are disclosed herein. In one example, a medical device may include a catheter shaft and a balloon assembly coupled to a distal region of the catheter shaft. Moreover, methods of making foldable transaction cards are provided. A threshold voltage is measured on the substrate to verify or confirm that a proper dopant level has been achieved. The minimum of one magnet may be positioned at different heights relative to the plane of the doctor edge, the magnetic force effective in the said plane depending on said heights.