PURPOSE: To prevent to generate distortion in a beam transmitting medium upon the sun tracking motion of the collector by a method wherein the beam transmitting medium, receiving the beams collected by the solar beam collector and transmitting them, are arranged coaxially with a rotary shaft supporting the beam collector.

CONSTITUTION: Second parabolar reflecting mirror 10 for converting the solar beam, reflected to the position of the focus of the parabola reflecting mirror 1 by the reflecting mirror 1, into parallel beams and reflecting them is provided, and the parallel beams, reflected by said reflecting mirror 10, and injected into first beam transmitting rod 11, being rotated coaxially and integrally with the first rotary shaft 2. The second beam transmitting rod 12, provided with an end rotatable with respect to said beam transmitting rod 11, is provided coaxially with the second rotary shaft 7 so as to enable to transmit said parallel beams to said beam transmitting rod 12 through the first beam transmitting rod 11. The parallel beams, transmitted to the beam transmitting rod 12, may be transmitted to any plate through the third beam transmitting rod 13 if necessary.