Image plane deviation amount detecting device

摘要

An image plane deviation amount detecting device includes means for converting the amount of lateral deviation between two object images formed by two light beams passing through two areas of the exit pupil of a focus detecting lens into an amount of image plane deviation including the sign and absolute amount thereof, whereby when utilized in an automatic focus apparatus, it is not only capable of effecting quick automatic focusing operation even when there is a response delay in the focus detecting device, but also capable of displaying the focus adjusted condition in the form of a quantitative amount of image plane deviation when utilized in a display device.