FIR filters are divided into partial filters that filter a same portion of image data to generate partial filtered results. A filling tool illustrating the invention includes at least one receptacle. The temperature sensitive piece 9 is affixed to a sheet-shaped base 1 with the waxed layer 7 being located close to the front face of the temperature sensor label. In a preferred embodiment the focal spot moves on a short scan saddle trajectory. The sled levitates above the ground using high-density permanent magnet arrays. At the center of the concave surface, a limit column is internally protruded.