A semiconductor device includes a nitride film between a gate electrode and an ohmic electrode contacting to a diffusion region adjacent to the gate electrode, at least on a side of the gate electrode facing the ohmic electrode. A plurality of indentations are formed in the internal surface for retaining the active agent to maintain the active agent in contact with the tooth when the stint is applied upon the tooth. The electric potential of the charge-sharing capacitor changes because of an inverted scanning signal output by the inverter and further alters the stored voltage applied on the second storage capacitor after the scan line finishes transmitting the scanning signal, so that the first storage capacitor and the second storage capacitor have different voltages. Information from the orthogonal color channel is used to perform channel mixing. The latter time constant may be substantially removed from the detector output with a discriminator.