Spectrum‐controllable color sensors using organic dyes

An organic color sensor was fabricated by using p‐ and n‐type dyes. The cell has a layered structure of Zn0/merocyanine/rhodamine B, which acts as an n‐p‐n‐ photodiode. The spectral sensitivity of the cell was changed remarkably by bias voltage, and a good separation of the spectral responses was obtained in the visible‐spectrum region.