Hi Fereshteh. I don't think so, because it has a threshold line and the signals below that are not accounted. This line discriminate background fluorescent from real amplification and the weak signals are being considered as a background fluorescent.
I think I find the answer of my question. Real time PCR assess all of the PCR mixture (all things that are in PCR tube) and PCR resolve only 5 to 6 microliter of PCR mixture on the gel electrophoresis , then Real time can detect lower amount of template.