OPTICAL MODULE

PROBLEM TO BE SOLVED: To obtain an optical module to which a plurality of optical lenses can easily be welded. SOLUTION: In the case of optically connecting an optical semiconductor device 5 with first lenses 21, 22, second lenses 12, 14, an inputting optical fiber 11 and an outputting optical fiber 13, the first lenses 21 and 22 of different focal distances are arranged with respect to the element 5 deviating positions on an optical axis lest the first lenses 21 and 22 obstruct welding of each other. Thus, the first lenses 21 and 22 can easily be welded and the optical module has high optical coupling efficiency.