An optical system for a stereo video endoscope including: first and second lens system channels each having optical elements in identical configurations, the optical elements being arranged in a same position along first and second optical axes, respectively, an optical axis of first and second optical elements coincide with the first and second optical axes, respectively, first and second cross-sectional areas of the first and second optical elements are inscribed in first and second circumferential circles, respectively, centers of first and second circumferential circles each coincide with the first and second optical axes, respectively, to define a maximum radius of the first optical element and the second optical element, the first and second circumferential circles overlap one another, and circumferential shapes of the first and second optical elements deviate from the first and second circumferential circles circumscribing them such that the first and second optical elements do not contact.