A system and a method for determining the refraction from a relative distance by using a camera, an illumination unit, a light blocking element unit and a control unit. The panel includes a substrate and the grid is provided on the panel so as to overlie the substrate. In another embodiment, the dielectric spacers may provide a region upon which un-landed vias may effectively land. Air pressure output from a torque converter escapes between the housing and the transmission pump to which it is connected. Electrons emitted from the cathode are influenced by the electric and magnetic fields to follow a path through the anode-cathode space and pass in close proximity to the plurality of pole pieces, and the gaps between adjacent pole pieces provide fringing fields which interact with the electrons to produce single mode operation at a desired operating frequency. Each set of the support blades is configured to load at least two substrates into the substrate boat.