High spatial resolution optical fiber two colour pyrometer with fast response Articles uri icon

publication date

  • February 2021

start page

  • 2942

end page

  • 2950


  • 3


  • 21

International Standard Serial Number (ISSN)

  • 1530-437X

Electronic International Standard Serial Number (EISSN)

  • 1558-1748


  • Among the different temperature measurement techniques providing micrometer resolution none of them provide fast response and easy access to close distances to the target surface in difficult to access areas. Optical fiber pyrometers provide that access but previous works used large optical fibers with numerical apertures limiting the minimum spot size to be measured. In this study, we propose a novel two colour optical fiber pyrometer based on a low diameter and numerical aperture optical fiber, low-noise photodetectors and high-gain transimpedance amplifiers with a high spatial resolution in the micrometre range and fast response. Using standard optical fibers and related devices provides also a low-cost system. The developed pyrometer presents a high spatial resolution of 16 μm for a target surface at 25 μm with a wide temperature range of 300 to 1200°C it being the highest spatial resolution for this kind of temperature systems. Theoretical analysis and measurements for different pyrometer configurations are reported. This study will help further the microthermography applications in machining processes.


  • Electronics
  • Telecommunications


  • multimode fiber; optical fiber; single mode fiber; spatial resolution; temperature measurement; two color pyrometer