A socket including multiple contact areas socket contacts is provided. The shield includes a shield side wall. Each lens has a focus scale on one of the lens system and the lens body that comprises a plurality of focus distance marks, and a focus index mark on the other of the lens system and the lens body. The programmable controller uses positional information from the sensors to determine the position of the movable elements on the path and control the movable elements. When a light-emitting unit emits a light source, the light source is uniformly given off through the light scattering structure, promoting use efficiency of the light source. One of the first and second passages is configured to communicate with the air delivery conduit and the other of the first and second passages is configured to communicate with the auxiliary conduit.