wwii n-8a gunsight

 

termed as rectiflector. antique

Designed for use both as a fixed gunsight for fighters and flexible gunnery gunsight for hand-held guns and turrets(a), the N-8 “Retiflector “(b) gunsight design departed from other AAF sights in that it employed a reflecting instead of a refracting collimator and used a Mangin mirror instead of a conventional lens.© Light from the lamp, mounted in a removable holder at the bottom of the sight, pass through a reticle fixed directly above it, then through the reflector plate to the Mangin collimating mirror at the top of the sight. After collimation, the light returns to the reflector plate from which it is reflected to the gunner’s eye."

United States Patent 5901452