Relationship between wavelength combination and signal-to-noise ratio in measuring hemoglobin concentrations using visible or near-infrared light

Tsukasa Funane, Hirokazu Atsumori, Hiroki Satou, Masashi Kiguchi, Atsushi Maki

Research output: Contribution to journalReview article

8 Citations (Scopus)


The signal-to-noise ratio (SNR), when using visible or near-infrared light to measure the change in hemoglobin concentration length (the product of hemoglobin concentration and optical path length in this study), depends on the wavelength combination and the analysis method. Although the SNRs increase when detected or incident optical power increases, the optical power should be limited because of safety standards. Considering these safety standards, we assumed that the total optical power was constant by using the relationship between optical power and measurement error. We investigated the theoretical estimation errors of the changes in hemoglobin concentration length using two, three, and four different wavelengths. The SNRs of the changes in hemoglobin concentration length were high when fewer wavelengths were used. These SNRs decreased when the redox state change in cytochrome oxidase was included in the analysis.

Original languageEnglish
Pages (from-to)442-448
Number of pages7
JournalOptical Review
Issue number4
Publication statusPublished - 2009 Oct 19
Externally publishedYes



  • Cytochrome oxidase
  • Hemoglobin concentration
  • Laser safety standards
  • Near-infrared light
  • Optical topography
  • Signal-to-noise ratio
  • Wavelength combination

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics

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