This imaging unit 1 comprises: an imaging board 10 that has a first main surface 10SA and a second main surface 10SB, wherein a light receiving circuit 11 is formed on the first main surface 10SA, while a through wiring 50 is arranged on the inner surface of a via hole H10 having an opening in the second main surface 10SB; a solder resist film 60 that is arranged on the second main surface 10SB around the via hole H10 and in a range that extends from the bottom of the via hole H10 but does not reach the second main surface 10SB; and a joint terminal 70 consisting of solder that covers the surface of the solder resist film 60 arranged in the via hole H10 and that is joined to the through wiring 50 that is not covered with the solder resist film 60 along the outer edge of the opening of the via hole H10.