ETH Zurich and Empa researchers built two working thin-film image sensors that stack colour-sensitive perovskite layers vertically. By changing the material's chemical composition, each layer absorbs a selected part of the spectrum while passing other wavelengths onward. The arrangement lets each pixel measure red, green and blue without the side-by-side colour filters used in conventional silicon sensors.
The Nature study advanced the team's earlier single-pixel demonstrations into functioning sensor prototypes with different readout architectures. The approach promises better use of incoming light, more accurate colour reproduction and fewer demosaicing artefacts. Its theoretical threefold advantage in light collection and spatial resolution is a consequence of the stacked design. The prototypes still had pixels 0.5 to 1 millimetre across, leaving substantial lateral miniaturisation and readout development before consumer-camera applications.
