Perhaps the best optical rangefinder was the Ranging Eagle Eye 3X.
So-called "optical rangefinders" became popular in the 1970s and '80s.
The submarine is equipped with a Zeiss Optronik (Oberkochen, Germany) OMS 100 non-hull-penetrating optronics mast accommodating a CCTV camera and a thermal imager; a Zeiss Optronik SERO 400 optical attack periscope with
optical rangefinder; TV and low-light-level TV, both developed together with Denel Eloptro (Pretoria, SA); plus a Thomson Scanter navigation radar mast.
Also, they found volunteer alfalfa plants along roadsides and measured the distance between them and the production fields with an
optical rangefinder or an automobile odometer.
In my experience a faster, more accurate, and easy to use system is the split-image
optical rangefinder. In essence, it works by "looking" at the same object from two different positions, i.e., triangulation.
From
optical rangefinders and periscopes for submarines in the late 19th century driving strong optical engineering research at universities, to the birth of an embryonic laser industry in the 1960s, the world's first single chip CMOS video camera in the 1980s, and to the development of III-V compound semiconductors and LiFi technology in the 21st century, Scotland can be truly proud of its photonics heritage.
In World War I,
optical rangefinders started to change the game for artillery spotters.
The days of awkward
optical rangefinders are almost gone forever.
