Extinction spectra of suspensions of microspheres: determination of the spectral refractive index and particle size distribution with nanometer accuracy
| Autor: | Markus Bär, Jonas Gienger, Jörg Neukammer |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Materials science
Forward scatter Mie scattering FOS: Physical sciences Physics::Optics 02 engineering and technology 01 natural sciences 010309 optics Cross section (physics) Optics 0103 physical sciences Electrical and Electronic Engineering Engineering (miscellaneous) Scattering business.industry 021001 nanoscience & nanotechnology Atomic and Molecular Physics and Optics Computational physics Extinction (optical mineralogy) Particle-size distribution Particle 0210 nano-technology business Refractive index Physics - Optics Optics (physics.optics) |
| Zdroj: | Applied Optics. 57:344 |
| ISSN: | 2155-3165 1559-128X |
| DOI: | 10.1364/ao.57.000344 |
| Popis: | A method is presented to infer simultaneously the wavelength-dependent real refractive index (RI) of the material of microspheres and their size distribution from extinction measurements of particle suspensions. To derive the averaged spectral optical extinction cross section of the microspheres from such ensemble measurements, we determined the particle concentration by flow cytometry to an accuracy of typically 2% and adjusted the particle concentration to ensure that perturbations due to multiple scattering are negligible. For analysis of the extinction spectra, we employ Mie theory, a series-expansion representation of the refractive index and nonlinear numerical optimization. In contrast to other approaches, our method offers the advantage to simultaneously determine size, size distribution, and spectral refractive index of ensembles of microparticles including uncertainty estimation. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|