Placing a metal cap over a small hole in a metal film does not stop light passing through, but rather enhances its transmission, according to new research.
A team at Princeton made an array of tiny holes in a thin metal film, then blocked each hole with an opaque metal cap. When they shined light into the holes, they found that as much as 70% more light came through when the holes were blocked than when they were open.
Researchers said the result could have significant implications and uses. For example, it might require scientists and engineers to rethink techniques they have been using when they want to block all light transmission, such as in very sensitive optical instruments like microscopes, telescopes, spectrometers and other optical detectors.
Read more at Princeton University