filar micrometer

instrument

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Last updated

June 26, 2026

Quick Summary

A filar micrometer is a device that can be attached to instruments like telescopes or microscopes to measure angles and separations. When fitted to a telescope, it's called a position micrometer and is used to determine position angles and the angular separation between celestial objects, such as double stars. When incorporated into a microscope eyepiece, it's known as a micrometer eyepiece. In this setup, the filar micrometer's lines are positioned in the focal plane, aligning with the magnified image when the microscope is in focus.12

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A filar micrometer, an instrument normally used in conjunction with a telescope for visual measurement of the separations of double stars, was employed to estimate the diameters of the first four known asteroids. The results established that Ceres was the largest asteroid, having a diameter estimated…
Read More
A filar micrometer, an instrument normally used in conjunction with a telescope for visual measurement of the separations of double stars, was employed to estimate the diameters of the first four known asteroids. The results established that Ceres was the largest asteroid, having a diameter estimated…
Read More