  Regenerated high-energy emissions from gamma-ray bursts (GRBs) are studied in
detail. If the intrinsic primary spectrum extends to the TeV range, these very
high-energy photons are absorbed by the cosmic infrared background (CIB).
Created high-energy electron-positron pairs up-scatter mainly cosmic microwave
background (CMB) photons, and secondary photons are generated in the GeV-TeV
range. These secondary delayed photons may be observed in the near future,
which are useful for a consistency check of the intrinsic primary spectrum. In
this paper, we focus on effects of the CIB on delayed secondary emissions. In
particular, we show that not only up-scattered CMB photons but also
up-scattered CIB ones are important, especially for low redshift bursts. They
also give us additional information on the CIB, whose photon density is not
definitely determined so far.
