  This paper presents the first results of a survey for bright quasars (V <
14.5 and R<15.4) covering the North Hemisphere at galactic latitudes |b|>30.
The photometric database is derived from the GSC and USNO catalogs. Quasars are
identified on the basis of their X-ray emission measured in the ROSAT All Sky
Survey. The surface density of quasars brighter than 15.5 mag turns out to be
$9 \pm 1 \cdot 10^{-3} deg^{-2}$, about 3 times higher than that estimated by
the PG survey. The quasar optical Luminosity Function (LF) at $0.04 < z \le
0.3$ is computed and shown to be consistent with a Luminosity Dependent
Luminosity Evolution of the type derived by La Franca and Cristiani (1997) in
the range $0.3 < z \le 2.2$. The predictions of semi-analytical models of
hierarchical structure formation agree remarkably well with the present
observations.
