Abstract: An optical transceiver of the present invention comprising an OSA, a circuit board, and a flexible substrate connecting these, in which the flexible substrate has high-speed signal lines and other lines other than the high speed signal lines provided separated from each other on the same surface, a ground layer placed apart and opposite these, and a resistive layer placed apart and opposite the high-speed signal lines, the other lines and the ground layer. High-speed signal and the resistive layer are opposite at least a part of the other lines.

Abstract: The present invention relates to a wiring member including: a copper foil layer having a smooth surface with a surface roughness Rz of 2 ?m or less; a noise suppressing layer containing a metallic material or a conductive ceramic and having a thickness of 5 to 200 nm; and an insulating resin layer provided between the smooth surface of the copper foil layer and the noise suppressing layer, and also relates to a printed wiring board equipped with the wiring member.