  A new optical state is described both analytically and numerically at the
boundary of a chiral medium with continuous helical symmetry of the dielectric
tensor. The tangential wave number is assumed to be zero. The state appears to
be localized near the boundary. It does not transfer energy along this boundary
and falls off exponentially with the distance from the boundary. The field
penetration into chiral medium is blocked at wavelengths close to the helical
pitch and corresponding to the photonic band gap. The polarization of light
near the boundary has the same sign of chirality as the helical medium. It is
shown that the homogeneous environment, or the substrate must exhibit the
anisotropic metallic reflection. Spectral manifestation of the state is
determined by the angle between the optical axes at the interface. A realistic
example is considered at the boundary of a cholesteric liquid crystal and a
metal-dielectric anisotropic nanocomposite.
