This telescope is exactly one power and has an objective, an erecting relay and an eyepiece. As can be seen in the diagram the direction of any object seen at the Entrance Pupil has the exact same direction at the Exit Pupil over the whole of the field of view assuming that the system.is completely corrected for distortion. If this is in fact the case then the direction of any object as seen at the Exit Pupil is constant as the axis of the telescope is rotated. This is the pure definition of a CONSTANT DEVIATION DEVICE.

Date Published: 1 January 1991
PDF: 7 pages
Proc. SPIE 1354, 1990 Intl Lens Design Conf, (1 January 1991); doi: 10.1117/12.47927

Published in SPIE Proceedings Vol. 1354:
1990 Intl Lens Design Conf
George N. Lawrence, Editor(s)