Imaging optical system and imaging apparatus

An imaging apparatus, comprising:

• an imaging optical system;
• and
• an image pickup device,
• wherein the imaging optical system includes:
• an imaging lens group having at least one lens;
• and
• an image side prism that bends light which has passed through the imaging lens group toward the image pickup device arranged at a predetermined position,
• wherein:
• the image side prism includes a reflection surface which reflects, toward the image pickup device, incident light proceeding from the imaging lens group, and an exit surface from which light reflected from the reflection surface emerges;
• the image side prism has a cut surface formed by cutting off a vertex portion between the reflection surface and the exit surface such that a whole normal light incident area within which normal light is incident on the reflection surface remains;
• the cut surface is a non-diffusing surface;
• and
• the image pickup device is arranged such that a sensor surface of the image pickup device is positioned on an image plane of the imaging optical system.