Optical module

An optical module comprising:

• a semiconductor optical device with a pair of first pads spaced apart in a first direction and with a second pad between the pair of first pads;
• a sub-board with a first circuit and a second circuit adjacent in the first direction on a surface thereof, the sub-board having a first back electrode on a back surface thereof to be electrically continuous to and overlap with the first circuit, the sub-board having a second back electrode on the back surface to be electrically continuous to and overlap with the second circuit, the sub-board being next to the semiconductor optical device in a second direction intersecting with the first direction;
• a pair of first wires electrically connecting the respective pair of first pads to the first circuit;
• a second wire electrically connecting the second pad to the second circuit;
• and
• a first capacitor and a second capacitor, over which the sub-board is placed, the first capacitor and the second capacitor being adjacent to each other in the first direction,
• the first capacitor being opposed to and electrically connected to the first back electrode,
• the second capacitor being opposed to and electrically connected to the second back electrode,
• each of the first circuit and the second circuit having a main region that overlaps with a corresponding one of the first capacitor and the second capacitor,
• at least one circuit of the first circuit and the second circuit having an extension region extending from the main region toward another circuit of the first circuit and the second circuit,
• at least one of one of the pair of first wires and the second wire being bonded to the extension region.