An alignment marker includes first marker element pieces for a first viewpoint and second marker element pieces for a second viewpoint different in plan shape. The first and second marker element pieces are respectively formed by dividing marker elements in such a way as to be equal in width to a predetermined marker element pitch. These pieces are arranged at the marker element pitch along an optical image separation direction of the optical image separation element. A predetermined number of the adjoining first and second pieces constitute one repetition cycle. A width of the repetition cycle is in accordance with an arrangement pitch of constituent elements of the optical image separation element. An existing optical image separation element can be used without the formation of the markers thereon and the alignment operation can be performed with a usual aligning and bonding apparatus.