| 摘要 |
<p>A periscopic sight (11, 13, 14) is mounted to extend through the wall of protective armour (23) surrounding a gun station. An elevation mirror (11) is exposed to receive light from the direction in which the gun is pointing and to reflect the light along a vertical path extending through the sight. A sealed unitary lens system (13) has a lens axis aligned with the vertical path and conducts the light therethrough to a stationary mirror (14) accessible to the eye (16) of an observer.</p><p>The sealed unitary lens systems has a sufficiently long eye relief to provide an unobstructed image to the observer in spite of the placement of the stationary mirror (14) between the lens system (13) and the observer (16).</p> |
