File:Reflector reflex sight howard grubb 1901.png

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Summary

Description	English: 1901 diagram of a version of Howard Grubb‘s collimating reflector (reflex) sight designed to make a compact version suitable for firearms and other small equipment. Ambient lighting of the reticle was improved by placing it facing up and bouncing it off a relay mirror then off a concave partially silvered collimating mirror.
Date	28 April 2011
Source	Adapted from “Journal of the Military Service Institution of the United States, Volume 37 By Military Service Institution of the United States”, page 552, published July-August, 1905
Author	BRIG GEN TF RODENBOUGH USA EDITOR
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