  The problem of imaging for a nearly-perfect lens, namely, a slab of a
left-handed material with refractive index n = -(1-sigma)^1/2 is solved
analytically for |sigma| << 1. The electromagnetic field behavior is determined
largely by singularities arising from the excitation of surface polaritons with
wavevector q -->oo. Depending on the sign of sigma, the near field is either
odd or even with respect to the lens middle plane. Images exhibit an anomalous
interference pattern with length scale determined by the width of the slab.
Consistent with recent studies by Smith et al. [Appl. Phys. Lett. 82, 1506
(2003)] and G'omez-Santos [Phys. Rev. Lett. 90, 077401 (2003)], the resolution
depends logarithmically on |sigma|.
