We report the discovery of four doubly imaged quasar lenses .
All the four systems are selected as lensed quasar candidates from the Sloan Digital Sky Survey data .
We confirm their lensing hypothesis with additional imaging and spectroscopic follow-up observations .
The discovered lenses are SDSS J0743+2457 with the source redshift z _ { s } = 2.165 , the lens redshift z _ { l } = 0.381 , and the image separation \theta = 1 \farcs 034 , SDSS J1128+2402 with z _ { s } = 1.608 and \theta = 0 \farcs 844 , SDSS J1405+0959 with z _ { s } = 1.810 , z _ { l } \approx 0.66 , and \theta = 1 \farcs 978 , and SDSS J1515+1511 with z _ { s } = 2.054 , z _ { l } = 0.742 , and \theta = 1 \farcs 989 .
It is difficult to estimate the lens redshift of SDSS J1128+2402 from the current data .
Two of the four systems ( SDSS J1405+0959 and SDSS J1515+1511 ) are included in our final statistical lens sample to derive constraints on dark energy and the evolution of massive galaxies .