An optical module includes a housing, a heat sink apparatus arranged in and thermally connected to the housing, and a printed circuit board partially arranged on the heat sink apparatus. The optical module further includes a first optoelectronic chip and a second optoelectronic chip that are both arranged on the heat sink apparatus. The first optoelectronic chip and second optoelectronic chip are both electrically connected to the printed circuit board. The printed circuit board has a first surface, a second surface opposite to the first surface, and an opening that extends from the first surface to the second surface. The second optoelectronic chip is arranged at the opening. The second optoelectronic chip is arranged separately from the first optoelectronic chip.