Emissivity measurements of reflective surfaces at near-millimeter wavelengths

J. J. Bock, M. K. Parikh, M. L. Fischer, A. E. Lange

Research output: Contribution to journalArticle

29 Scopus citations

Abstract

We have developed an instrument for directly measuring the emissivity of reflective surfaces at near-millimeter wavelengths. The thermal emission of a test sample is compared with that of a reference surface, allowing the emissivity of the sample to be determined without heating. The emissivity of the reference surface is determined by one's heating the reference surface and measuring the increase in emission. The instrument has an absolute accuracy of Δ∊ = 5 × 10−4 and can reproducibly measure a difference in emissivity as small as Δ∊ = 10−4 between flat reflective samples. We have used the instrument to measure the emissivity of metal films evaporated on glass and carbon fiber-reinforced plastic composite surfaces. We measure an emissivity of (2.15 ± 0.4) × 10−3 for gold evaporated on glass and (2.65 ± 0.5) × 10−3 for aluminum evaporated on carbon fiber-reinforced plastic composite.

Original languageEnglish (US)
Pages (from-to)4812-4816
Number of pages5
JournalApplied Optics
Volume34
Issue number22
DOIs
StatePublished - Aug 1995
Externally publishedYes

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Keywords

  • Emissivity
  • Infrared
  • Millimeter
  • Mirrors
  • Reflectance

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics
  • Engineering (miscellaneous)
  • Electrical and Electronic Engineering

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