  In the superlens problem, the presence of the reflected wave plays a critical
role in the energy and information transfer from the object to recording
device: both incident and reflected evanescent waves are required to insure
nonzero energy/information flux from the object to the recorder. Therefore an
optimization is required between the image quality (characterized by a transfer
function) and information transfer rate (characterized by the
energy/information flux). It is shown that the introduction of the recording
device may lead to the deterioration in the image quality as compared to the
ideal case when no recording device is present. The decline in the image
quality is due to the generation of phase-shifted reflected evanescent wave
between the lens and the recorder. It is also shown that the magnitude of the
energy flux depends on the amount of dissipation in the lens and the recorder
in a non-monotonous way.
