US Patent 7637259 Solar collector

The invention relates to a solar collector comprising an absorber tube (13) supported by supports. Radiation-permeable cladding tubes (15) are located between the supports and surround the absorber tube (13). Compensation pieces (17) are provided between the cladding tubes (15) due to the fact that the absorber tube (13) and the cladding tubes (15) have different expansion behaviors. In order to also capture radiation that strikes the connection area (50), at least one mirror collar (20) is provided that reflects the solar radiation into the area of the active absorber tube surface. This mirror collar (20) is capable of reflecting the concentrated solar radiation coming from different directions from the parabolic mirrors even at different solar angles of incidence upon the active absorber surface.