Abstract: An optical module adapted to combine a first and a second light beam into a mixed light beam is provided. The optical module includes a base, an optoelectronic element and an optical dichroic element. The base has an accommodating space. The optoelectronic element is adapted in the accommodating space. The optical dichroic element is adapted on the base. The optical dichroic element includes a transparent element, a first reflector and a second reflector. The transparent element is adapted to let the first light beam and the second light beam pass through. The first and second reflector are disposed on the transparent element. The first reflector is adapted to reflect the first light beam to the second reflector. The second reflector is adapted to reflect the first light beam and let the second light beam pass through. The first and the second reflector are opposite and not parallel to each other on the transparent element, and there is an angle between the first and the second reflector.

Abstract: A beam-splitting integrated optical element including a shell, at least one first lens, and at least one second lens is provided. The shell includes a first lens surface, a second lens surface, at least one first reflective surface, and at least one second reflective surface. A bottom edge of each first reflective surface and a bottom edge of each second reflective surface are not connected to each other. The at least one first lens is disposed on the first lens surface. The at least one second lens is disposed on the second lens surface, and each second lens has a second optical axis. Each second reflective surface is located at at least one side of the corresponding second optical axis and located on a transmission path of only a portion of a first beam. An optical transmitter module incorporating said beam-splitting optical element is also provided.