scholarly journals Оптические свойства in vitro катарактальных хрусталиков глаза человека в видимом и ближнем ИК диапазонах-=SUP=-*-=/SUP=-

2019 ◽  
Vol 126 (5) ◽  
pp. 656
Author(s):  
А.В. Беликов ◽  
А.М. Загорулько ◽  
С.Н. Смирнов ◽  
А.Н. Сергеев ◽  
А.А. Михайлова ◽  
...  
Keyword(s):  
Absorption Coefficient ◽  
Spectral Range ◽  
Anisotropy Factor ◽  
Optical Characteristics ◽  
Scattering Coefficient ◽  
Eye Lens ◽  
Human Eye ◽  
Scattering Anisotropy ◽  
Reduced Scattering Coefficient

Spectral dependences of absorption coefficient, scattering coefficient, anisotropy factor and reduced scattering coefficient for in vitro human eye lenses of different cataract type are investigated. The spectra of absorption coefficient and reduced scattering coefficient were obtained for the spectral range 400-2300 nm, and the spectra of scattering coefficient and scattering anisotropy factor - for the spectral range 400-1800 nm. The regions of wavelengths within which the spectra of the studied optical characteristics of the human eye lens are not statistically significantly different for samples with different stages of cataract maturity and, conversely, within which they are statistically significantly different, are determined.

IMPROVE OPTICAL CLEARING OF SKIN IN VITRO WITH PROPYLENE GLYCOL AS A PENETRATION ENHANCER

2009 ◽  
Vol 02 (03) ◽  
pp. 269-278 ◽  
Author(s):  
ZHONGWEI ZHI ◽  
ZHENZHEN HAN ◽  
QINGMING LUO ◽  
DAN ZHU
Keyword(s):  
Propylene Glycol ◽  
Diffuse Reflectance ◽  
Treatment Time ◽  
Optical Transmittance ◽  
Penetration Enhancer ◽  
Penetration Enhancers ◽  
Scattering Coefficient ◽  
Optical Clearing ◽  
Reduced Scattering Coefficient

In order to enhance the optical clearing effect of topically applied optical clearing agents (OCAs), we evaluated the effect of propylene glycol (PG) as a chemical penetration enhancer (PE) on optical clearing of skin in vitro by observation and measurement of optical-transmittance and diffuse-reflectance spectra. Three OCAs, i.e., glycerol, D-sorbitol and PEG400, and two other penetration enhancers, Azone and Thiazone, were used in this study. The results indicated that the decrease of reduced scattering coefficient caused by OCA/PG was larger than that by pure OCA, and the change by OCA/water was the least after the same treatment time. There were significant differences for the reduced scattering coefficient at 630 nm after 120 min application of agents between OCA and OCA/PG. The efficacy of optical clearing caused by OCA/PG depended on the OCA itself. When PEG400 was mixed with three different PEs, we found the optical clearing were different. The penetration enhancing ability of PG was much better compared to Azone, and suboptimal to Thiazone. Also, this study provides evidence for the use of PG as a PE in order to improve skin optical clearing.

scholarly journals In Vitro Assessment of Optical Properties of Blood by Applying the Extended Huygens-Fresnel Principle to Time-Domain Optical Coherence Tomography Signal at 1300 nm

2008 ◽  
Vol 2008 ◽  
pp. 1-6 ◽  
Author(s):  
Dan P. Popescu ◽  
Michael G. Sowa
Keyword(s):  
Optical Coherence Tomography ◽  
Attenuation Coefficient ◽  
Direct Method ◽  
Anisotropy Parameter ◽  
Anisotropy Factor ◽  
Measured Signal ◽  
Optical Coherence ◽  
Total Attenuation ◽  
Scattering Anisotropy

A direct method for the measurement of the optical attenuation coefficient and the scattering anisotropy parameter based on applying the extended Huygens-Fresnel principle to optical coherence tomography images of blood is demonstrated. The images are acquired with a low-power probing beam at the wavelength of 1300 nm. Values of 12.15 mm−1and 0.95 are found for the total attenuation coefficient and the scattering anisotropy factor, respectively. Also, as a preliminary step, the optical refraction index is determined with a precision of two decimal numbers directly from optical coherence images. The total attenuation coefficient and the scattering anisotropy factor are determined with precisions within experimental error margins of 5% and 2%, respectively. Readable OCT signal is obtained for a maximum propagation of light into blood of 0.25 mm. At the maximum probed depth, the measured signal is almost103smaller than its initial intensity when entering the sample.

scholarly journals Broadband spectroscopy for characterization of tissue-like phantom optical properties

2017 ◽  
Vol 23 (4) ◽  
pp. 121-126 ◽  
Author(s):  
Ali Shahin ◽  
Wesam Bachir
Keyword(s):  
Optical Properties ◽  
Absorption Coefficient ◽  
Spectral Range ◽  
Diffuse Reflectance ◽  
Visible Spectral Range ◽  
Scattering Coefficient ◽  
Visible Range ◽  
Broadband Spectroscopy ◽  
Analytical Expressions

Abstract Optical phantoms are widely used for evaluating the performance of biomedical optical modalities, and hence, absorbing and scattering materials are required for the construction of optical phantoms. Towards that aim, new readily available and inexpensive black Ink (Parker) as a simulating absorber as well as Intralipid 20% as a simulating scatterer are thoroughly investigated. Broadband Transmittance and Diffuse reflectance spectroscopic measurements were performed in the visible range 400 – 700 nm. Optical properties of the phantom materials are determined. Analytical expressions for absorption and scattering coefficient related to the concentrations and wavelength of the Parker ink and Intralipid are also presented and discussed. The results show nonlinear trend in the absorption coefficient of Parker ink over the examined visible spectral range. Furthermore, Intralipid scattering coefficient variation across the mentioned spectral range shows a tissue-like scattering trend. The findings demonstrate the capability of the broadband transmission and diffuse reflectance for characterizing tissue-like phantom materials in the examined spectral range.

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