VIDEO CAMERA HAVING AN ADAPTIVE AUTOMATIC IRIS CONTROL CIRCUIT

A video camera includes a lens, an iris and an iris driving circuit, an image sensor, a circuit for dividing the picture into a plurality of sub-areas for extracting the luminance of each sub-area according to the luminance signal provided from the image sensor as a luminance distribution signal, a circuit for generating a signal defining a target value of an iris driving signal, an adaptive circuit using an artificial neural network to which the luminance distribution signal is input for carrying out adaptive conversion so that the offset between a provided teacher signal and its own output is minimized, and a switch for selecting either the target value signal or the output of the adaptive circuit to provide the same as a teacher signal to the adaptive circuit.