  We derive new limits on the value of the cosmological constant, $\Lambda$,
based on the Einstein bending of light by systems where the lens is a distant
galaxy or a cluster of galaxies. We use an amended lens equation in which the
contribution of $\Lambda$ to the Einstein deflection angle is taken into
account and use observations of Einstein radii around several lens systems. We
use in our calculations a Schwarzschild-de Sitter vacuole exactly matched into
a Friedmann-Robertson-Walker background and show that a $\Lambda$-contribution
term appears in the deflection angle within the lens equation. We find that the
contribution of the $\Lambda$-term to the bending angle is larger than the
second-order term for many lens systems. Using these observations of bending
angles, we derive new limits on the value of $\Lambda$. These limits constitute
the best observational upper bound on $\Lambda$ after cosmological constraints
and are only two orders of magnitude away from the value determined by those
cosmological constraints.
