Subsurface microscopy of integrated circuits with angular spectrum and polarization control.

We investigate the effect of an annular pupil-plane aperture in confocal imaging while using an NA increasing lens. We show that focal spot shape is highly sensitive to both polarization and angular spectrum of the incoming light. We demonstrate a lateral spatial resolution of 145 nm (lambda(0)/9) in the direction perpendicular to the polarization direction.

Phase-sensitive detection of dipole radiation in a fiber-based high numerical aperture optical system.

We theoretically study the problem of detecting dipole radiation in a fiber-based confocal microscope of high numerical aperture. By using a single-mode fiber, in contrast to a hard-stop pinhole aperture, the detector becomes sensitive to the phase of the field amplitude. We find that the maximum in collection efficiency of the dipole radiation does not coincide with the optimum resolution for the light-gathering instrument. The derived expressions are important for analyzing fiber-based confocal microscope performance in fluorescence and spectroscopic studies of single molecules and/or quantum dots.