The quasar SDSS J133401.39+331534.3 at z = 2.426 is found to be a two-image gravitationally lensed quasar with the image separation of 0 \farcs 833 .
The object is first identified as a lensed quasar candidate in the Sloan Digital Sky Survey Quasar Lens Search , and then confirmed as a lensed system from follow-up observations at the Subaru and University of Hawaii 2.2-meter telescopes .
We estimate the redshift of the lensing galaxy to be 0.557 based on absorption lines in the quasar spectra as well as the color of the galaxy .
In particular , we observe the system with the Subaru Telescope AO188 adaptive optics with laser guide star , in order to derive accurate astrometry , which well demonstrates the usefulness of the laser guide star adaptive optics imaging for studying strong lens systems .
Our mass modeling with improved astrometry implies that a nearby bright galaxy \sim 4 ^ { \prime \prime } apart from the lensing galaxy is likely to affect the lens potential .