optical range finder

instrument

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Last updated

July 1, 2026

Quick Summary

An optical range finder is an instrument used to measure the distance to an object. It works by using lenses and prisms to correct for parallax, allowing the user to view an object from two slightly separated points simultaneously. The distance is determined by measuring the angles formed by the lines of sight from each end of the instrument.12

There are two main types:
* Coincidence range finders: Used in cameras and surveying, they have a single eyepiece.1
* Stereoscopic range finders: Resemble coincidence types but have two eyepieces, making them more effective for tracking moving objects.1

While historically used in military applications, radar and laser range finders have largely replaced optical versions for many tasks.1

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range finder
One basic type is the optical range finder modeled after a ranging device developed by the Scottish firm of Barr and Stroud in the 1880s. The optical range finder is usually classified into two kinds, coincidence and stereoscopic.
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One basic type is the optical range finder modeled after a ranging device developed by the Scottish firm of Barr and Stroud in the 1880s. The optical range finder is usually classified into two kinds, coincidence and stereoscopic.
Read More

tank
Fire control
…systems was the adoption of optical range finders, first on the M47 tank and then on the Leopard 1, the AMX-30, and other tanks. In the 1960s, optical range finders began to be replaced by laser range finders. In combination with electronic ballistic computers, these greatly increased the hit probability…
Read More
…systems was the adoption of optical range finders, first on the M47 tank and then on the Leopard 1, the AMX-30, and other tanks. In the 1960s, optical range finders began to be replaced by laser range finders. In combination with electronic ballistic computers, these greatly increased the hit probability…
Read More