Abstract: A current collector comprising: a folded region in which an end part of a multi-layered structure having an insulation layer sandwiched by electrically conductive layers is folded at least twice in the same direction; the electrically conductive layers sandwiching the insulation layer being electrically connected to each other in the folded region; and inside surfaces of the end part of the current collector forming the folded region being either separated from each other or partially in contact with each other.
Abstract: A mode splitter and the magneto-optical pick-up device including the mode splitter. The mode splitter includes a tapered waveguide portion whose thickness gradually becomes thin so that a light of at least one mode can be cut off. An emission position of a light wave can be varied depending on its mode. In this mode splitter, the emission position of the light wave of each mode can be adjusted by changing a thickness of the tapered waveguide, thereby improving the degree of freedom in designing the device.