Patent ID: 7981230

Claim:
A method for fabricating an optical device, comprising: bonding a first prism with a second prism via an adhesive, wherein the first prism is a polygonal-columnar prism comprising a first set of longitudinal sides that extend between a first set of bases and the second prism is a polygonal-columnar prism comprising a second set of longitudinal sides that extend between a second set of bases; and putting the first prism and the second prism, thus bonded together, onto a joining jig; and pressing the first prism and the second prism via the joining jig, wherein the joining jig comprises: a first holding plate and a second holding plate that is arranged opposite the first holding plate, wherein a gap is defined between the first and second holding plates; and a precision plate held between a first surface of the first holding plate and a first surface of the second holding plate that is directly opposite the first surface of the first holding plate, wherein, during the pressing: a first surface of one of the first set of longitudinal sides of the first prism is placed in contact with and pressed against a surface of the precision plate exposed to the gap, with a second surface of another one of the first set of longitudinal sides of the first prism placed in contact with and pressed against a second surface of the first holding plate, and with one of the second set of longitudinal sides of the second prism placed in contact with and pressed against a second surface of the second holding plate that is directly opposite the second surface of the first holding plates.