Provided is a light transmission device which achieves light transmission with a small loss and a small output fluctuation due to rotation by a noncontact and highly durable light connector connecting method while achieving a reduction in reflection noise. Specifically and a light transmission device (102) is provided with a rotation drive section provided with a light adapter (602) to which an APC light connecter is connected, and a fixed section which transmits light from/to the rotation drive section and the device being characterized by being provided with an optical member (613, 614 and 616) configured such that light emitted from a ferrule of the APC light connector connected to the light adapter (602) is emitted as axisymmetric parallel light that is symmetric with respect to the rotation axis of the rotation drive section to the fixed section and the axisymmetric parallel light emitted from the fixed section enters as deflected or condensed light to the ferrule and wherein noncontact light transmission is performed between the ferrule of the APC light connector connected to the light adapter (602) and the fixed section.
