Patent ID: 7043163

Claim:
An optical transmission device comprising: a connector housing having an insert hole through which an optical plug for transmitting an optical signal is inserted and detachably supporting the optical plug; an optical element including at least either a light emitting element or a light receiving element and being arranged in proximity to a tip of the optical plug supported in the housing to send and receive the optical signal to and from the optical plug; and a driving circuit section for driving the optical element, wherein the driving circuit section is arranged in a closer position to the insert hole than the optical element along the optical plug; wherein the optical element includes a light emitting element and a light receiving element and the driving circuit section includes a signal processing circuit board for the light receiving element and a driving circuit board for the light emitting element, and wherein the signal processing circuit board for the light receiving element and the driving circuit board for the light emitting element have a grounding layer on a rear surface, respectively, and the grounding layers are opposed to each other to have an optical plug in the middle of them.