Patent ID: 8648260

Claim:
A wiring substrate comprising: a pair of differential wirings; a first insulating layer that is provided adjacent to one side of the pair of differential wirings, the first insulating layer including first fiber bundles disposed in parallel to an extending direction of the pair of differential wirings; a second insulating layer that is provided adjacent to another side of the pair of differential wirings, the second insulating layer including second fiber bundles disposed in parallel to the extending direction of the pair of differential wirings, the second fiber bundles being disposed by the same pitch as the first fiber bundles; a third insulating layer that is provided on a side of the first insulating layer and opposite to a side of the first insulating layer that is adjacent to the pair of differential wirings, the third insulating layer including third fiber bundles disposed in parallel to the extending direction of the pair of differential wirings; and a fourth insulating layer that is provided on a side of the second insulating layer and opposite to a side of the second insulating layer that is adjacent to the pair of differential wirings, the fourth insulating layer including fourth fiber bundles disposed in parallel to the extending direction of the pair of differential wirings, wherein intervals between the third fiber bundles and intervals between the fourth fiber bundles are respectively narrower than intervals between the first fiber bundles and intervals between the second fiber bundles, and the pair of differential wirings are disposed between adjacent ones of the first fiber bundles at positions that do not overlap the first fiber bundles in a planar view, and are disposed between adjacent ones of the second fiber bundles at positions that do not overlap the second fiber bundles in a planar view.