The present invention relates to a sewer system comprising a sewage receptacle, sewer piping connected to the sewage receptacle by means of a discharge valve, a vacuum generating means for generating vacuum in the sewer piping, and a control mechanism for controlling the discharge valve. A metal layer is formed on a silicon-based substrate comprising a gate with a spacer on the side wall of the gate and a sourcedrain is provided. The optically transparent receiver tube may include a transparent tube wall fabricated from at least one of the following materials; single crystal alumina, aluminum oxynitride, spinel, quartz or magnesium aluminum oxide. Thus, it is possible to select a required menu item from a plurality of menu items just by moving a finger while touching the protrusion portion, without several pushes of operation keys. In this way, asymmetry can be detected. A clear plastic or transparent band surrounds a \u03bcPol based 3D stereo flat panel LCD display system.