EROS has been monitoring few million stars in the Magellanic clouds , as well as toward the Galactic bulge and spiral arms since 1996 , to search for microlensing events .
In this paper , we present briefly the EROS setup and scientific program and discuss the results obtained from our observations in four directions in the Galactic plane , away from the bulge .
Seven light curves , out of 9.1 million stars observed in these directions show luminosity variations interpreted as due to microlensing .
The averaged estimated optical depth \bar { \tau } = 0.45 ^ { +0.24 } _ { -0.11 } is compatible with expectations from simple Galactic models .
Nonetheless a small excess of short time-scale events may be present in the direction closest to the Galactic center .