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.