The present disclosure relates to systems, vehicles, and methods for detecting optical defects in an optical path of a camera system. An example system may include an image sensor configured to provide images of a field of view via an optical path that extends through an optical window. The system also includes at least one phase-detection device and a controller. The controller is configured to execute instructions stored in the memory so as to carry out various operations, including receiving, from the image sensor, first pixel information indicative of an image of the field of view. The operations additionally include receiving, from the at least one phase-detection device, second pixel information indicative of a portion of the field of view. The operations yet further include determining, based on the first pixel information and the second pixel information, at least one optical defect associated with the optical path.