Dataset Information

Method for Measuring Absolute Optical Properties of Turbid Samples in a Standard Cuvette.

ABSTRACT: Many applications seek to measure a sample's absorption coefficient spectrum to retrieve the chemical makeup. Many real-world samples are optically turbid, causing scattering confounds which many commercial spectrometers cannot address. Using diffusion theory and considering absorption and reduced scattering coefficients on the order of 0.01 mm^-1 and 1 mm^-1, respectively, we develop a method which utilizes frequency-domain to measure absolute optical properties of turbid samples in a standard cuvette (45 mm × 10 mm × 10 mm). Inspired by the self-calibrating method, which removes instrumental confounds, the method uses measurements of the diffuse complex transmittance at two sets of two different source-detector distances. We find: this works best for highly scattering samples (reduced scattering coefficient above 1 mm^-1); higher relative error in the absorption coefficient compared to the reduced scattering coefficient; accuracy is tied to knowledge of the sample's index of refraction. Noise simulations with 0.1 % amplitude and 0.1° = 1.7 mrad phase uncertainty find errors in absorption and reduced scattering coefficients of 4 % and 1 %, respectively. We expect that higher error in the absorption coefficient can be alleviated with highly scattering samples and that boundary condition confounds may be suppressed by designing a cuvette with high index of refraction. Further work will investigate implementation and reproducibility.

SUBMITTER: Blaney G

PROVIDER: S-EPMC10557469 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature

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Method for Measuring Absolute Optical Properties of Turbid Samples in a Standard Cuvette.

Blaney Giles G Sassaroli Angelo A Fantini Sergio S

Applied sciences (Basel, Switzerland) 20221027 21

Many applications seek to measure a sample's absorption coefficient spectrum to retrieve the chemical makeup. Many real-world samples are optically turbid, causing scattering confounds which many commercial spectrometers cannot address. Using diffusion theory and considering absorption and reduced scattering coefficients on the order of 0.01 mm<sup>-1</sup> and 1 mm<sup>-1</sup>, respectively, we develop a method which utilizes frequency-domain to measure absolute optical properties of turbid sa ...[more]

PMID: 37811485

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Dataset Information

Method for Measuring Absolute Optical Properties of Turbid Samples in a Standard Cuvette.

Publications

Method for Measuring Absolute Optical Properties of Turbid Samples in a Standard Cuvette.

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