Each the contact terminal includes a plurality of contact units stacked with each other, wherein contact point sections of the respective contact units are distributed to disperse in lengthwise direction of the contact terminal within the corresponding contact pad. The micro shutter includes a flat portion having at least one opening, a main concave portion adjacent to the opening and extending in from the flat portion to a first depth, and at least one sub-concave portion extending in from a bottom surface of the main concave portion to second depth. The connectors include first through eighth input contacts that are mounted on the printed circuit board and first through eighth output contacts that are likewise mounted on the printed circuit board. The test socket is mounted on a burn-in board, thus allowing a semiconductor package having a non-pin grid array footprint to be tested without requiring an interposer for converting the non-pin grid array footprint of the semiconductor package. Such metal mesh structures are fabricated through rolling mask lithography. This enables an optical coupling to be effected between a stationary optical fiber bundle and a moving optical fiber bundle when the two optical fiber bundles are arranged around one or more shaft portions that prevent the area occupied by the shaft portion to be used to effect an optical coupling.