An image pickup apparatus includes an imaging optical system, an image
sensor, an image signal processing section and a light-amount
characteristic giving section. The imaging optical system has a
distortion in such a way as to form an image whose center part is
stretched, and whose peripheral part is squeezed. The image sensor has a
light reception surface at which a subject image is formed through the
imaging optical system, and converts the formed subject image into image
signals. The image signal processing section performs an image processing
for correcting the image signals with respect to the distortion. The
light-amount characteristic giving section gives the subject image a
characteristic in which the amount of light at a center part of the
subject image formed at the light-reception surface of the image sensor
is larger than that at a peripheral part of the subject image.