From the first epoch observations of the VIMOS VLT Deep Survey ( VVDS ) up to z = 1.5 we have derived luminosity functions of different spectral type galaxies .
The VVDS data , covering \sim 70 \% of the life of the Universe , allow for the first time to study from the same sample and with good statistical accuracy the evolution of the luminosity functions by galaxy type in several rest frame bands from a purely magnitude selected sample .
The magnitude limit of the VVDS ( I _ { AB } = 24 ) is significantly fainter than the limit of other complete spectroscopic surveys and allows the determination of the faint end slope of the luminosity function with unprecedented accuracy .
Galaxies have been classified in four spectral classes , from early type to irregular galaxies , using their colours and redshift , and luminosity functions have been derived in the U , B , V , R and I rest frame bands for each type , in redshift bins from z = 0.05 to z = 1.5 .
In all the considered rest frame bands , we find a significant steepening of the luminosity function going from early to late types .
The characteristic luminosity M ^ { * } of the Schechter function is significantly fainter for late type galaxies and this difference increases in the redder bands .
Within each of the galaxy spectral types we find a brightening of M ^ { * } with increasing redshift , ranging from \lower 2.15 pt \hbox { $ \buildrel < \over { \sim } $ } 0.5 mag for early type galaxies to \sim 1 mag for the latest type galaxies , while the slope of the luminosity function of each spectral type is consistent with being constant with redshift .
The luminosity function of early type galaxies is consistent with passive evolution up to z \sim 1.1 , while the number of bright ( M _ { B _ { AB } } < -20 ) early type galaxies has decreased by \sim 40 \% from z \sim 0.3 to z \sim 1.1 .
We also find a strong evolution in the normalization of the luminosity function of latest type galaxies , with an increase of more than a factor 2 from z \sim 0.3 to z \sim 1.3 : the density of bright ( M _ { B _ { AB } } < -20 ) late type galaxies in the same redshift range increases of a factor \sim 6.6 .
These results indicate a strong type-dependent evolution and identifies the latest spectral types as responsible for most of the evolution of the UV-optical luminosity function out to z = 1.5 .