Abstract: A solar collector is provided having an absorber (100), which has a front side (102) facing toward the solar radiation during use and a back side (103) facing away from the solar radiation during use, a transparent cover (200) arranged essentially plane-parallel opposite the front side (102) of the absorber (100), and a back wall (300) arranged opposite the back side (103) of the absorber (100). The solar collector distinguishes itself in that the back wall (300) is constructed as a transparent pane, in particular a glass pane or plastic pane, and contains, at least in some regions, a medium which reflects infrared radiation and is reflective in the direction of the back side (103) of the absorber (100). Further, a composite pane is provided, in particular a composite glass pane (1), an absorber (100), and a use of such an absorber (100) in solar collectors and composite panes. This absorber can also have a coating for the reduction of heat emission (low-e).