Baseline scale - Kisenjaku

…The side whose length is known is called the baseline, and measuring this length is called baseline surveying. In Japan's first-order triangulation surveys, baselines of several kilometers were measured using a 25-meter tape measure made of an amber alloy called a baseline measure. In recent years, the use of laser range finders, which measure distance by measuring the time it takes for light to travel between triangulation points, has become widespread, making it possible to measure distances easily and with high accuracy. …

*Some of the terminology explanations that mention "baseline measure" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…この長さのわかった辺を基線と呼び，この長さを測量することを基線測量と呼ぶ。日本の一等三角測量では数kmの基線を，25mのアンバー系合金製の基線尺と呼ぶ巻尺で測定していた。近年光が三角点間を往復する時間を測定して距離を求める光波測距儀が普及し，距離を手軽に高精度で測定することが可能となった。…

※「基線尺」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報