Correction of an adding-doubling inversion algorithm for the measurement of the optical parameters of turbid media

Abstract

We present broadband measurements of the optical properties of tissue-mimicking solid phantoms using a single integrating sphere to measure the hemispherical reflectance and transmittance under a direct illumination at the normal incident angle. These measurements are traceable to reflectance and transmittance scales. An inversion routine using the output of the adding-doubling algorithm restricted to the reflectance and transmittance under a direct illumination was developed to produce the optical parameters of the sample along with an uncertainty budget at each wavelength. The results for two types of phantoms are compared to measurements by time-resolved approaches. The results between our method and these independent measurements agree within the estimated measurement uncertainties.

Machine learning estimation of tissue optical properties

“…Initial experiments were conducted using synthetic tissue samples with known optical properties. Syndaver tissue coupons (Syndaver, USA) with Asian pigment levels were imaged with the streak camera microscope described above, and the optical properties of these samples were previously validated by NIST using a dual integrating sphere system 22 , 23 . As each row of the kymograph from a streak camera provides a photon distribution for a point in time, where temporal resolution is controlled by the voltage ramp applied to the streak tube, we can resolve the diffusion and attenuation of photons interacting with a tissue sample by evaluating each row of pixels in the image.…”

Measurement of copper ion exit through apex of human single canal teeth following of electrophoresis

“…In this study, supernatant and spectrophotometry techniques were used to measure the amount of copper extracted from the apical foramen. In chemistry, spectrophotometry is the quantitative measurement of the reflection or transmission properties of a material as a function of wavelength ( 10 ). The extract was prepared in 0.15 mol/l and centrifuged to get the supernatant.…”

“…1 ) Copper ions derived from the copper paste were mobilized via a low current electric field (1.5 mA/min for 10 min) by Depotphorese® (Gerät Original II, Humanchemie, Germany) The amount of copper around the root in the solution was measured by the spectrophotometric method and supernatant. [Spectrophotometry is the quantitative measurement of the reflection or transmission properties of a material as a function of wavelength ( 10 )]. The extract was prepared in 0.15 mol/L and centrifuged to get the supernatant.…”

High-speed alignment optimization of digital optical phase conjugation systems based on autocovariance analysis in conjunction with orthonormal rectangular polynomials

“…The wavelength-dependent optical properties of the 5-mm-thick phantom were measured by a single integrating sphere installed at the National Institute of Standards and Technology, and the scattering and absorption coefficients were measured by a modified inverse adding double algorithm. The experimental setup and details of the algorithms are described elsewhere 33 …”