High-Sensitivity Color Imaging Using Pixel-Scale Color Splitters Based on Dielectric Metasurfaces

Conventional color image sensors employing absorptive color filters exhibit low overall light transmission, resulting in limited signal levels per sensor pixel. This issue is becoming critical because the amount of light to detect at each pixel is decreasing as pixel size decreases. Here, we present a design for transparent, pixel-scale color splitters based on dielectric metasurfaces and show the advantages of using them in color image sensors instead of filters. We demonstrate that the image sensor configurations with the color splitters enhance the amount of detected light by a factor of ∼3.57 compared with a conventional color filter scheme, while preserving the resolution and color image quality.