PURPOSE: To quickly and surely execute joining by soldering and to give sufficient joining strength by providing a single or plural apertures according to an area to reduce the calorific capacity of a supporting member.

CONSTITUTION: A member 5 filling up a gap between a main body structural member 4 and the holding member 3 of an image sensor 1 is shaped so as to be brought into contact or closely arranged by giving the sufficient length or area. However, since a soldering part is hardly warmed even when a soldering iron is made to abut on it because the volume of the soldering part is increased and the joining becomes unsure because the spread of the soldering is adverse state, the aperture is formed at the joining part and the calorific capacity of the joining part is reduced. Then, the joining by the soldering is made sure in a short time. Holes 4c and 4d near the bent parts 4a and 4b of the member 4 are provided so as to reduce the calorific capacity of the bent parts 4a and 4b by considering it. On the other hand, slits 5g and 5h are provided at the bent parts 5e and 5f of the member 5.