Plasmonic color filter with robustness against cross talk for compact imaging applications

In high resolution imaging devices, smaller aperture in the color filter causes cross talk which provides incorrect information. Plasmonic color filters (PCFs) have been reported as an alternative of the conventional color resist based-color filter (CRCF) and many studies on PCFs demonstrated the filtering function by PCFs with a sub-micron size. In this work, we investigated the cross talk performance of PCFs compared to CRCFs. The effect of cross talk over distance from the filter were measured for each filter. Despite poorer spectral filtering characteristics, PCFs were more robust against cross talk than CRCFs. Also, the further away from the filter, the more cross talk appeared. As a result, PCFs showed less cross talk than CRCFs at about 82% of the results measured at a distance of 2~10 µm. This study will help to make practical use of PCFs in high-resolution imaging applications.