Filar micrometer
（重定向自Position micrometer）
![A filar micrometer attached to a telescope](/Images/godic/202502/03/lossy-page1-220px-Ladd_Observatory_micrometer.tiff5709.jpg")
![Filar micrometer](/Images/godic/202502/03/Lille_-_observatoire_-_55709.jpg")
A filar micrometer is a specialized eyepiece used in astronomical telescopes for astrometry measurements, in microscopes for specimen measurements, and in alignment and surveying telescopes for measuring angles and distances on nearby objects. The word filar derives fromLatin filum, meaning "a thread". It refers to the fine threads or wires used in the device.