1. A camera unit for monitoring a vehicle periphery comprising: a pickup element; and a lens system in which light rays from a prescribed range of a visual field are imaged onto the pickup element, wherein with respect to a relationship between an image height of respective image portions on an image formed on the pickup element and an image angle of the light lays made incident into the respective image portions, the lens system is configured so that an amount of change in the image height with respect to a change in the image angle is greater at a peripheral portion of the image than at a center part of the image, the lens system comprises: (1) a first lens system which is a wide angle lens system configured to be a fisheye lens and (2) a second lens system which is an anamorphic lens system which enlarges in the vertical direction the image formed on the pickup element, and a focal distance of the lens system is in the horizontal direction.