Abstract: An amplification MOSFET in a source ground form receives at its gate an output signal of a source-follower circuit through a second capacitor. The source-follower circuit, on the otherhand, receives a voltage of a first capacitor which receives a signal charge. A predetermined bias voltage is supplied to the gate of the amplification MOSFET through a switch device while the signal charge of the first capacitor is reset. According to this structure, the second capacitor can transmit only the signal component and the voltage signal itself can be amplified by the source ground type amplification MOSFET. The amplification MOSFET can be biased to its optimum operation point by the switch device during the reset period of the first capacitor; hence, sensitivity can be substantially improved with a simple circuit structure.

Abstract: An improved multi-color liquid crystal display system which is capable of making visual color representation of more than eight colors in a display panel, such as a liquid crystal display panel which is composed of liquid crystal cells having three primary color filters attached thereto. Lightness of a cell is controlled by causing the cell to be in "ON" state during M frames out of N frames (N>M) to thereby provide half-tone color representation of the cell. This enables increase of the number of colors represented with the three primary color cells more than eight by combining "ON", "OFF" and the "half-tone" states of the three primary color cells.