  Recent FIR/submm deep surveys revealed large number of ULIGs, which are
proposed to lie at z>1, and in normally interacting systems with very dusty
environments. We discussed in a previous paper that a population with a fast
evolving infrared burst phase triggered by gas rich mergers at z~1 interpreted
successfully the steep slope of IRAS 60um counts, leaving still a reasonable
CIRB level at this wavelength. To extend the model to mid- and far-IR, we adopt
a template SED as typical for nearby IR bright galaxies, such as Arp220. We
construct the SED for the starburst mergers at z~1 by a simple dust extinction
law and a thermal continuum assumption for the FIR emission. Since the
radiation process at MIR for the merging systems is still uncertain, we assume
it is similar to that of Arp220, but modify it by the observed flux correlation
of ULIGs from IRAS, ISOCAM deep surveys. We show in this paper that the strong
evolution of the ELAIS 90um, ISO 170um and the SCUBA 850um could be
sufficiently accounted for by such an evolutionary scenario, especially for the
hump of the ISOCAM 15um source count around 0.4mJy. From current best fit
results, we find that the dust temperature of those merging system at z~1 would
be higher than that of Arp220 for a reconciliation of the multi-wavelength deep
surveys. The major difference of our current model prediction is that we see a
fast convergence of the differential number counts at 60um below 50mJy, which
is about a factor of two brighter than other model predictions. Future IR
satellite like Astro-F,SIRTF would give strong constraints to the models.
