An output circuit for CCD imager devices or CCD delay devices is disclosed in which a depletion type second MIS transistor is connected to the drain side of a first MIS transistor constituting a source follower adapted for converting transferred signal signals into an electrical voltage, and an output voltage is supplied to the gate of the second MIS transistor. This depletion type second MIS transistor causes the drain potential of the first MIS transistor to be changed in phase with the input electrical charges to reduce the gate-to-drain capacitance of the first MIS transistor to improve the charge-to-voltage conversion gain.