An alarm device for signaling when an object reaches a specified condition. The article may be an article such as a potted plant and the cover may be a decorative cover. A dispenser to dispense the polymer solution over the substrate extends into the coating chamber. Therefore, the luminance of each of the plurality of lamps can be maintained uniformly. The carbon black is in a content of 7% to 17% by mass and has at least two peaks in its particle size number distribution. The system uses data from the inertial navigation system and from the digital elevation map for real-time calculating direction to selected area portions, and for maintaining the direction during integration of light from the terrain, and for producing corresponding images of area portions.