Abstract: An image distortion correcting apparatus for a television camera. In addition to an analogue correcting waveform, four corner independent distortion correcting waveforms are employed for rough adjustment together with a digital distortion correcting signal serving for fine adjustment. These waveforms are combined to be utilized for correcting image distortion from which the television camera suffers. A high-accuracy correction of image distortion can be accomplished with a circuit configuration of a small scale.

Abstract: A system for measuring the state of charge of a storage battery is disclosed which corrects charging and discharge electrical quantities of the battery in view of temperature and charging efficiency of the battery, and the like to precisely measure the state of charge thereof by digital-operation. There is also disclosed a system correcting, by digital-operation, the variation in capacity of the battery due to the variation in life of the battery and/or the self-discharge thereof as well, to thereby measure the state of charge with higher precision.