Determination of continuous complex refractive index dispersion of biotissue based on internal reflection

Abstract. The complex refractive index dispersion (CRID), which contains the information on the refractive index dispersion and extinction coefficient spectra, is an important optical parameter of biotissue. However, it is hard to perform the CRID measurement on biotissues due to their high scattering property. Continuous CRID measurement based on internal reflection (CCRIDM-IR) is introduced. By using a lab-made apparatus, internal reflectance spectra of biotissue samples at multiple incident angles were detected, from which the continuous CRIDs were calculated based on the Fresnel formula. Results showed that in 400- to 750-nm range, hemoglobin solution has complicated dispersion and extinction coefficient spectra, while other biotissues have normal dispersion properties, and their extinction coefficients do not vary much with different wavelengths. The normal dispersion can be accurately described by several coefficients of dispersion equations (Cauchy equation, Cornu equation, and Conrady equation). To our knowledge, this is the first time that the continuous CRID of scattering biotissue over a continuous spectral region is measured, and we hereby have proven that CCRIDM-IR is a good method for continuous CRID research of biotissue.

[1]  Ge Zhang,et al.  Measurement of the refractive index of biotissue at four laser wavelengths , 2002, SPIE/COS Photonics Asia.

[2]  S Andersson-Engels,et al.  Measurements of the optical properties of tissue in conjunction with photodynamic therapy. , 1995, Applied optics.

[3]  Chunping Zhang,et al.  Continuous refractive index dispersion measurement based on derivative total reflection method. , 2015, The Review of scientific instruments.

[4]  S. Bali,et al.  Real-time differential refractometry without interferometry at a sensitivity level of 10(-6). , 2006, Applied optics.

[5]  L Wang,et al.  MCML--Monte Carlo modeling of light transport in multi-layered tissues. , 1995, Computer methods and programs in biomedicine.

[6]  Alexandre Douplik,et al.  Refractive index of solutions of human hemoglobin from the near-infrared to the ultraviolet range: Kramers-Kronig analysis , 2012, Journal of biomedical optics.

[7]  V. Tuchin,et al.  The refractive index of human hemoglobin in the visible range , 2011, Physics in medicine and biology.

[8]  F. P. Bolin,et al.  Refractive index of some mammalian tissues using a fiber optic cladding method. , 1989, Applied optics.

[9]  A Roggan,et al.  Optical properties of ocular fundus tissues--an in vitro study using the double-integrating-sphere technique and inverse Monte Carlo simulation. , 1995, Physics in medicine and biology.

[10]  John A. Nelder,et al.  A Simplex Method for Function Minimization , 1965, Comput. J..

[11]  J. Fujimoto,et al.  Determination of the refractive index of highly scattering human tissue by optical coherence tomography. , 1995, Optics letters.

[12]  A. He,et al.  Experimental measurement of the refractive index of biological tissues by total internal reflection. , 2005, Applied optics.

[13]  Jianguo Tian,et al.  Measurement of the complex refractive index of tissue-mimicking phantoms and biotissue by extended differential total reflection method. , 2011, Journal of biomedical optics.

[14]  M. Daimon,et al.  Measurement of the refractive index of distilled water from the near-infrared region to the ultraviolet region. , 2007, Applied optics.

[15]  D. Sardar,et al.  Optical Properties of Whole Blood , 1998, Lasers in Medical Science.

[16]  Da Xing,et al.  Determination of optical properties of normal and adenomatous human colon tissues in vitro using integrating sphere techniques. , 2005, World journal of gastroenterology.

[17]  Jun Q. Lu,et al.  Refractive indices of human skin tissues at eight wavelengths and estimated dispersion relations between 300 and 1600 nm , 2006, Physics in medicine and biology.

[18]  R. Birge,et al.  Modified critical angle method for measuring the refractive index of bio-optical materials and its application to bacteriorhodopsin , 1995 .

[19]  S C Gebhart,et al.  In vitro determination of normal and neoplastic human brain tissue optical properties using inverse adding-doubling , 2006, Physics in medicine and biology.