VIEWING APPARATUS WITH A COUNTERBALANCED AND ARTICULATED MIRROR

An articulated viewing apparatus (10) has a pair of elevational actuators (56, 78), one of which is a coarse-position actuator (56) and the other of which is a fine-position actuator (78), and each of which pivots a mirror head (28) about respective parallel elevational axes (54, 66'). Pivotal movements of the mirror head (28) direct the line of sight of a viewer looking outwardly through a window (22). The window (22) may be formed in the wall of a vehicle or may be at the upper end of a periscope tube, for example, and includes a transparent material (24). This window (22) may admit light to an optical sensor or to the user's eye directly. The coarse-position elevational actuator (56) is positioned so that its axis (54) is located as close as possible to an edge of the mirror head (28) and close to the inner surface of the window glazing (24) so that the size of the window (22) is minimized with respect to the size of the optical aperture and field of view provided to the user of the apparatus (10). The fine-position actuator (78) is attached to the mirror head (28) at a respective axis (66') approximately at the geometric center of the mirror (28), so that the mirror (28) is statically balanced about the fine-position elevation axis (66') of this actuator (78).