<p>A light transmitting device is provided with a light transmitting section having a light emitting element; a light receiving section having a constant current source, which generates a bias current for driving the light emitting element, and a light receiving element; a light transmitting medium which optically connects the light emitting element and the light receiving element with each other; and a power transmitting section which transmits the bias current from the constant current source to the light emitting element.</p>
