| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical transmission module with which it is possible to align the optical axes of an optical element and an optical block without using a protrusion and a fitting hole for positioning and suppress the effect of heat from a heat generating substance, and the packaging structure of the optical block.SOLUTION: An optical transmission module 1 comprises: a multilayer circuit board 2 in which a plurality of wiring layers are formed and which has first and second principal planes 2a, 2b; an optical element 3 mounted on the bottom face 21a of a recess 21 and electrically connected to a second wiring layer 20from an uppermost layer; a circuit element 4 electrically connected to a second wiring layer 20from a lowermost layer; an optical block 5 disposed position-adjustably in parallel to the first principal plane 2a and optically coupled with the optical element 3; and an adhesive 6 for bonding the first principal plane 2a and the optical block 5. |
