Abstract

Conventional optical refractometry methods are often limited by a narrow measurement range, complex hardware, or relatively high cost. Here, we present a novel refractometry method to measure the bulk refractive index (RI) of materials (including solids and liquids) using lensless holographic on-chip imaging and autofocusing, which is simple, cost-effective, and has a large RI measurement range. As a proof of concept, two compact prototypes were built to measure the RIs of solid materials and liquids, respectively, and they were tested by measuring the RIs of a ZnSe plate and a microscopy immersion oil. Experimental results show that our devices have an average accuracy of ~3 × 10−4 RI unit (RIU) with an estimated precision of ~3 × 10−3 RIU for solids; and an average accuracy of ~1 × 10−4 RIU with an estimated precision of ~3 × 10−4 RIU for liquids. We believe that this cost-effective and portable RI measurement platform holds promise to be used in laboratory and industrial settings.

© 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Full Article  |  PDF Article
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References

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2018 (1)

2017 (6)

Z. Ren, N. Chen, and E. Y. Lam, “Automatic focusing for multisectional objects in digital holography using the structure tensor,” Opt. Lett. 42(9), 1720–1723 (2017).
[Crossref] [PubMed]

M. Stchakovsky, Y. Battie, and A. E. Naciri, “An original method to determine complex refractive index of liquids by spectroscopic ellipsometry and illustrated applications,” Appl. Surf. Sci. 421, 802–806 (2017).
[Crossref]

C. Prokop, N. Irmler, B. Laegel, S. Wolff, A. Mitchell, and C. Karnutsch, “Optofluidic refractive index sensor based on air-suspended SU-8 grating couplers,” Sens. Actuators A Phys. 263, 439–444 (2017).
[Crossref]

L. Ji, X. Sun, G. He, Y. Liu, X. Wang, Y. Yi, C. Chen, F. Wang, and D. Zhang, “Surface plasmon resonance refractive index sensor based on ultraviolet bleached polymer waveguide,” Sens. Actuators B Chem. 244, 373–379 (2017).
[Crossref]

M. Rostykus and C. Moser, “Compact lensless off-axis transmission digital holographic microscope,” Opt. Express 25(14), 16652–16659 (2017).
[Crossref] [PubMed]

Y. Zhang, H. Wang, Y. Wu, M. Tamamitsu, and A. Ozcan, “Edge sparsity criterion for robust holographic autofocusing,” Opt. Lett. 42(19), 3824–3827 (2017).
[Crossref] [PubMed]

2016 (4)

W. Luo, Y. Zhang, A. Feizi, Z. Göröcs, and A. Ozcan, “Pixel super-resolution using wavelength scanning,” Light Sci. Appl. 5(4), e16060 (2016).
[Crossref] [PubMed]

Y. Zhang, S. Y. C. Lee, Y. Zhang, D. Furst, J. Fitzgerald, and A. Ozcan, “Wide-field imaging of birefringent synovial fluid crystals using lens-free polarized microscopy for gout diagnosis,” Sci. Rep. 6(1), 28793 (2016).
[Crossref] [PubMed]

Y. Zhang, Y. Wu, Y. Zhang, and A. Ozcan, “Color calibration and fusion of lens-free and mobile-phone microscopy images for high-resolution and accurate color reproduction,” Sci. Rep. 6(1), 27811 (2016).
[Crossref] [PubMed]

E. S. R. Fonseca, P. T. Fiadeiro, M. Pereira, and A. Pinheiro, “Comparative analysis of autofocus functions in digital in-line phase-shifting holography,” Appl. Opt. 55(27), 7663–7674 (2016).
[Crossref] [PubMed]

2015 (5)

W. Luo, A. Greenbaum, Y. Zhang, and A. Ozcan, “Synthetic aperture-based on-chip microscopy,” Light Sci. Appl. 4(3), e261 (2015).
[Crossref]

C. Zuo, J. Sun, J. Zhang, Y. Hu, and Q. Chen, “Lensless phase microscopy and diffraction tomography with multi-angle and multi-wavelength illuminations using a LED matrix,” Opt. Express 23(11), 14314–14328 (2015).
[Crossref] [PubMed]

C. Y. Tan and Y. X. Huang, “Dependence of Refractive Index on Concentration and Temperature in Electrolyte Solution, Polar Solution, Nonpolar Solution, and Protein Solution,” J. Chem. Eng. Data 60(10), 2827–2833 (2015).
[Crossref]

M. Yahya and M. Z. Saghir, “Prediction and Experimental Measurement of Refractive Index in Ternary Hydrocarbon Mixtures,” J. Chem. Eng. Data 60(8), 2329–2342 (2015).
[Crossref]

M. L. Dongare, P. B. Buchade, and A. D. Shaligram, “Refractive index based optical Brix measurement technique with equilateral angle prism for sugar and Allied Industries,” Optik (Stuttg.) 126(20), 2383–2385 (2015).
[Crossref]

2013 (1)

2012 (3)

2010 (1)

2008 (1)

2007 (1)

2006 (2)

F. Rogerson and C. Symington, “A method for the estimation of alcohol in fortified wines using hydrometer Baume and refractometer Brix,” Am. J. Enol. Vitic. 57, 486–490 (2006).

N. Lue, G. Popescu, T. Ikeda, R. R. Dasari, K. Badizadegan, and M. S. Feld, “Live cell refractometry using microfluidic devices,” Opt. Lett. 31(18), 2759–2761 (2006).
[Crossref] [PubMed]

2005 (1)

2004 (1)

2003 (1)

1997 (2)

H. Hattori, H. Yamanaka, H. Kurniawan, S. Yokoi, and K. Kagawa, “Using minimum deviation of a secondary rainbow and its application to water analysis in a high-precision, refractive-index comparator for liquids,” Appl. Opt. 36(22), 5552–5556 (1997).
[Crossref] [PubMed]

G. H. Meeten, “Refractive index errors in the critical-angle and the Brewster-angle methods applied to absorbing and heterogeneous materials,” Meas. Sci. Technol. 8(7), 728–733 (1997).
[Crossref]

1996 (2)

1995 (2)

M. C. Simon and P. A. Larocca, “Minimum deviation for uniaxial prisms,” Appl. Opt. 34(4), 709–715 (1995).
[Crossref] [PubMed]

W. Lukosz, “Integrated optical chemical and direct biochemical sensors,” Sens. Actuators B Chem. 29(1-3), 37–50 (1995).
[Crossref]

1990 (1)

T. R. Corner, T. C. Beaman, J. T. Greenamyre, and P. Gerhardt, “Spectrophotometric determination of refractive index increment for bacterial cells,” J. Microbiol. Methods 11(3-4), 255–260 (1990).
[Crossref]

1983 (1)

1973 (1)

1968 (1)

1966 (1)

1959 (1)

R. Barer and D. A. T. Dick, “Interferometry and refractometry of snail amoebocytes,” Exp. Cell Res. 16(2), 285–291 (1959).
[Crossref] [PubMed]

1957 (1)

1951 (1)

C. R. Parkerson, “Determination of Saturation Temperatures of Inorganic Salt Solutions. Refractive Index Measurements,” Anal. Chem. 23(4), 610–613 (1951).
[Crossref]

Badizadegan, K.

Barer, R.

R. Barer and D. A. T. Dick, “Interferometry and refractometry of snail amoebocytes,” Exp. Cell Res. 16(2), 285–291 (1959).
[Crossref] [PubMed]

R. Barer, “Refractometry and Interferometry of Living Cells,” J. Opt. Soc. Am. 47(6), 545–556 (1957).
[Crossref] [PubMed]

Battie, Y.

M. Stchakovsky, Y. Battie, and A. E. Naciri, “An original method to determine complex refractive index of liquids by spectroscopic ellipsometry and illustrated applications,” Appl. Surf. Sci. 421, 802–806 (2017).
[Crossref]

Beaman, T. C.

T. R. Corner, T. C. Beaman, J. T. Greenamyre, and P. Gerhardt, “Spectrophotometric determination of refractive index increment for bacterial cells,” J. Microbiol. Methods 11(3-4), 255–260 (1990).
[Crossref]

Buchade, P. B.

M. L. Dongare, P. B. Buchade, and A. D. Shaligram, “Refractive index based optical Brix measurement technique with equilateral angle prism for sugar and Allied Industries,” Optik (Stuttg.) 126(20), 2383–2385 (2015).
[Crossref]

Chen, C.

L. Ji, X. Sun, G. He, Y. Liu, X. Wang, Y. Yi, C. Chen, F. Wang, and D. Zhang, “Surface plasmon resonance refractive index sensor based on ultraviolet bleached polymer waveguide,” Sens. Actuators B Chem. 244, 373–379 (2017).
[Crossref]

Chen, L.

Chen, N.

Chen, Q.

Ciddor, P. E.

Coppola, G.

Corner, T. R.

T. R. Corner, T. C. Beaman, J. T. Greenamyre, and P. Gerhardt, “Spectrophotometric determination of refractive index increment for bacterial cells,” J. Microbiol. Methods 11(3-4), 255–260 (1990).
[Crossref]

Dan, D.

Dasari, R. R.

De Nicola, S.

Dick, D. A. T.

R. Barer and D. A. T. Dick, “Interferometry and refractometry of snail amoebocytes,” Exp. Cell Res. 16(2), 285–291 (1959).
[Crossref] [PubMed]

Dongare, M. L.

M. L. Dongare, P. B. Buchade, and A. D. Shaligram, “Refractive index based optical Brix measurement technique with equilateral angle prism for sugar and Allied Industries,” Optik (Stuttg.) 126(20), 2383–2385 (2015).
[Crossref]

Feizi, A.

W. Luo, Y. Zhang, A. Feizi, Z. Göröcs, and A. Ozcan, “Pixel super-resolution using wavelength scanning,” Light Sci. Appl. 5(4), e16060 (2016).
[Crossref] [PubMed]

Feld, M. S.

Ferraro, P.

Fiadeiro, P. T.

Fitzgerald, J.

Y. Zhang, S. Y. C. Lee, Y. Zhang, D. Furst, J. Fitzgerald, and A. Ozcan, “Wide-field imaging of birefringent synovial fluid crystals using lens-free polarized microscopy for gout diagnosis,” Sci. Rep. 6(1), 28793 (2016).
[Crossref] [PubMed]

Fonseca, E. S. R.

Furst, D.

Y. Zhang, S. Y. C. Lee, Y. Zhang, D. Furst, J. Fitzgerald, and A. Ozcan, “Wide-field imaging of birefringent synovial fluid crystals using lens-free polarized microscopy for gout diagnosis,” Sci. Rep. 6(1), 28793 (2016).
[Crossref] [PubMed]

Gao, P.

Gerhardt, P.

T. R. Corner, T. C. Beaman, J. T. Greenamyre, and P. Gerhardt, “Spectrophotometric determination of refractive index increment for bacterial cells,” J. Microbiol. Methods 11(3-4), 255–260 (1990).
[Crossref]

Gillen, G. D.

Göröcs, Z.

W. Luo, Y. Zhang, A. Feizi, Z. Göröcs, and A. Ozcan, “Pixel super-resolution using wavelength scanning,” Light Sci. Appl. 5(4), e16060 (2016).
[Crossref] [PubMed]

Greenamyre, J. T.

T. R. Corner, T. C. Beaman, J. T. Greenamyre, and P. Gerhardt, “Spectrophotometric determination of refractive index increment for bacterial cells,” J. Microbiol. Methods 11(3-4), 255–260 (1990).
[Crossref]

Greenbaum, A.

Guha, S.

Guo, R.

Guo, X.

Hale, G. M.

Hao, J.

Hassani, K.

Hattori, H.

He, G.

L. Ji, X. Sun, G. He, Y. Liu, X. Wang, Y. Yi, C. Chen, F. Wang, and D. Zhang, “Surface plasmon resonance refractive index sensor based on ultraviolet bleached polymer waveguide,” Sens. Actuators B Chem. 244, 373–379 (2017).
[Crossref]

Hu, Y.

Huang, Y. X.

C. Y. Tan and Y. X. Huang, “Dependence of Refractive Index on Concentration and Temperature in Electrolyte Solution, Polar Solution, Nonpolar Solution, and Protein Solution,” J. Chem. Eng. Data 60(10), 2827–2833 (2015).
[Crossref]

Ikeda, T.

Iodice, M.

Irmler, N.

C. Prokop, N. Irmler, B. Laegel, S. Wolff, A. Mitchell, and C. Karnutsch, “Optofluidic refractive index sensor based on air-suspended SU-8 grating couplers,” Sens. Actuators A Phys. 263, 439–444 (2017).
[Crossref]

Ji, L.

L. Ji, X. Sun, G. He, Y. Liu, X. Wang, Y. Yi, C. Chen, F. Wang, and D. Zhang, “Surface plasmon resonance refractive index sensor based on ultraviolet bleached polymer waveguide,” Sens. Actuators B Chem. 244, 373–379 (2017).
[Crossref]

Kagawa, K.

Kao, C. F.

Karnutsch, C.

C. Prokop, N. Irmler, B. Laegel, S. Wolff, A. Mitchell, and C. Karnutsch, “Optofluidic refractive index sensor based on air-suspended SU-8 grating couplers,” Sens. Actuators A Phys. 263, 439–444 (2017).
[Crossref]

Khmaladze, A.

Kim, M.

Kurniawan, H.

Laegel, B.

C. Prokop, N. Irmler, B. Laegel, S. Wolff, A. Mitchell, and C. Karnutsch, “Optofluidic refractive index sensor based on air-suspended SU-8 grating couplers,” Sens. Actuators A Phys. 263, 439–444 (2017).
[Crossref]

Lam, E. Y.

Larocca, P. A.

Lee, S. Y. C.

Y. Zhang, S. Y. C. Lee, Y. Zhang, D. Furst, J. Fitzgerald, and A. Ozcan, “Wide-field imaging of birefringent synovial fluid crystals using lens-free polarized microscopy for gout diagnosis,” Sci. Rep. 6(1), 28793 (2016).
[Crossref] [PubMed]

Lei, M.

Li, H.

Liu, T. S.

Liu, Y.

L. Ji, X. Sun, G. He, Y. Liu, X. Wang, Y. Yi, C. Chen, F. Wang, and D. Zhang, “Surface plasmon resonance refractive index sensor based on ultraviolet bleached polymer waveguide,” Sens. Actuators B Chem. 244, 373–379 (2017).
[Crossref]

Lo, C.-M.

Lu, S. H.

Lue, N.

Lukosz, W.

W. Lukosz, “Integrated optical chemical and direct biochemical sensors,” Sens. Actuators B Chem. 29(1-3), 37–50 (1995).
[Crossref]

Luo, W.

W. Luo, Y. Zhang, A. Feizi, Z. Göröcs, and A. Ozcan, “Pixel super-resolution using wavelength scanning,” Light Sci. Appl. 5(4), e16060 (2016).
[Crossref] [PubMed]

W. Luo, A. Greenbaum, Y. Zhang, and A. Ozcan, “Synthetic aperture-based on-chip microscopy,” Light Sci. Appl. 4(3), e261 (2015).
[Crossref]

Ma, B.

Meeten, G. H.

G. H. Meeten, “Refractive index errors in the critical-angle and the Brewster-angle methods applied to absorbing and heterogeneous materials,” Meas. Sci. Technol. 8(7), 728–733 (1997).
[Crossref]

Min, J.

Mitachi, S.

Mitchell, A.

C. Prokop, N. Irmler, B. Laegel, S. Wolff, A. Mitchell, and C. Karnutsch, “Optofluidic refractive index sensor based on air-suspended SU-8 grating couplers,” Sens. Actuators A Phys. 263, 439–444 (2017).
[Crossref]

Miyashita, T.

Moser, C.

Naciri, A. E.

M. Stchakovsky, Y. Battie, and A. E. Naciri, “An original method to determine complex refractive index of liquids by spectroscopic ellipsometry and illustrated applications,” Appl. Surf. Sci. 421, 802–806 (2017).
[Crossref]

Nahal, A.

Naraghi, R. R.

Ozcan, A.

Y. Zhang, H. Wang, Y. Wu, M. Tamamitsu, and A. Ozcan, “Edge sparsity criterion for robust holographic autofocusing,” Opt. Lett. 42(19), 3824–3827 (2017).
[Crossref] [PubMed]

Y. Zhang, Y. Wu, Y. Zhang, and A. Ozcan, “Color calibration and fusion of lens-free and mobile-phone microscopy images for high-resolution and accurate color reproduction,” Sci. Rep. 6(1), 27811 (2016).
[Crossref] [PubMed]

W. Luo, Y. Zhang, A. Feizi, Z. Göröcs, and A. Ozcan, “Pixel super-resolution using wavelength scanning,” Light Sci. Appl. 5(4), e16060 (2016).
[Crossref] [PubMed]

Y. Zhang, S. Y. C. Lee, Y. Zhang, D. Furst, J. Fitzgerald, and A. Ozcan, “Wide-field imaging of birefringent synovial fluid crystals using lens-free polarized microscopy for gout diagnosis,” Sci. Rep. 6(1), 28793 (2016).
[Crossref] [PubMed]

W. Luo, A. Greenbaum, Y. Zhang, and A. Ozcan, “Synthetic aperture-based on-chip microscopy,” Light Sci. Appl. 4(3), e261 (2015).
[Crossref]

A. Greenbaum and A. Ozcan, “Maskless imaging of dense samples using pixel super-resolution based multi-height lensfree on-chip microscopy,” Opt. Express 20(3), 3129–3143 (2012).
[Crossref] [PubMed]

Pan, S. P.

Parkerson, C. R.

C. R. Parkerson, “Determination of Saturation Temperatures of Inorganic Salt Solutions. Refractive Index Measurements,” Anal. Chem. 23(4), 610–613 (1951).
[Crossref]

Pereira, M.

Pinheiro, A.

Popescu, G.

Prokop, C.

C. Prokop, N. Irmler, B. Laegel, S. Wolff, A. Mitchell, and C. Karnutsch, “Optofluidic refractive index sensor based on air-suspended SU-8 grating couplers,” Sens. Actuators A Phys. 263, 439–444 (2017).
[Crossref]

Querry, M. R.

Ren, Z.

Rogerson, F.

F. Rogerson and C. Symington, “A method for the estimation of alcohol in fortified wines using hydrometer Baume and refractometer Brix,” Am. J. Enol. Vitic. 57, 486–490 (2006).

Rostykus, M.

Saber, A.

Saghir, M. Z.

M. Yahya and M. Z. Saghir, “Prediction and Experimental Measurement of Refractive Index in Ternary Hydrocarbon Mixtures,” J. Chem. Eng. Data 60(8), 2329–2342 (2015).
[Crossref]

Shaligram, A. D.

M. L. Dongare, P. B. Buchade, and A. D. Shaligram, “Refractive index based optical Brix measurement technique with equilateral angle prism for sugar and Allied Industries,” Optik (Stuttg.) 126(20), 2383–2385 (2015).
[Crossref]

Shumate, M. S.

Simon, M. C.

Stchakovsky, M.

M. Stchakovsky, Y. Battie, and A. E. Naciri, “An original method to determine complex refractive index of liquids by spectroscopic ellipsometry and illustrated applications,” Appl. Surf. Sci. 421, 802–806 (2017).
[Crossref]

Sun, J.

Sun, X.

L. Ji, X. Sun, G. He, Y. Liu, X. Wang, Y. Yi, C. Chen, F. Wang, and D. Zhang, “Surface plasmon resonance refractive index sensor based on ultraviolet bleached polymer waveguide,” Sens. Actuators B Chem. 244, 373–379 (2017).
[Crossref]

Symington, C.

F. Rogerson and C. Symington, “A method for the estimation of alcohol in fortified wines using hydrometer Baume and refractometer Brix,” Am. J. Enol. Vitic. 57, 486–490 (2006).

Tamamitsu, M.

Tan, C. Y.

C. Y. Tan and Y. X. Huang, “Dependence of Refractive Index on Concentration and Temperature in Electrolyte Solution, Polar Solution, Nonpolar Solution, and Protein Solution,” J. Chem. Eng. Data 60(10), 2827–2833 (2015).
[Crossref]

Tavassoly, M. T.

Wang, F.

L. Ji, X. Sun, G. He, Y. Liu, X. Wang, Y. Yi, C. Chen, F. Wang, and D. Zhang, “Surface plasmon resonance refractive index sensor based on ultraviolet bleached polymer waveguide,” Sens. Actuators B Chem. 244, 373–379 (2017).
[Crossref]

Wang, H.

Wang, X.

L. Ji, X. Sun, G. He, Y. Liu, X. Wang, Y. Yi, C. Chen, F. Wang, and D. Zhang, “Surface plasmon resonance refractive index sensor based on ultraviolet bleached polymer waveguide,” Sens. Actuators B Chem. 244, 373–379 (2017).
[Crossref]

Werner, A. J.

Wolff, S.

C. Prokop, N. Irmler, B. Laegel, S. Wolff, A. Mitchell, and C. Karnutsch, “Optofluidic refractive index sensor based on air-suspended SU-8 grating couplers,” Sens. Actuators A Phys. 263, 439–444 (2017).
[Crossref]

Wu, Y.

Y. Zhang, H. Wang, Y. Wu, M. Tamamitsu, and A. Ozcan, “Edge sparsity criterion for robust holographic autofocusing,” Opt. Lett. 42(19), 3824–3827 (2017).
[Crossref] [PubMed]

Y. Zhang, Y. Wu, Y. Zhang, and A. Ozcan, “Color calibration and fusion of lens-free and mobile-phone microscopy images for high-resolution and accurate color reproduction,” Sci. Rep. 6(1), 27811 (2016).
[Crossref] [PubMed]

Xie, S.

Xu, Z.

Yahya, M.

M. Yahya and M. Z. Saghir, “Prediction and Experimental Measurement of Refractive Index in Ternary Hydrocarbon Mixtures,” J. Chem. Eng. Data 60(8), 2329–2342 (2015).
[Crossref]

Yamanaka, H.

Yan, S.

Yao, B.

Ye, T.

Yi, Y.

L. Ji, X. Sun, G. He, Y. Liu, X. Wang, Y. Yi, C. Chen, F. Wang, and D. Zhang, “Surface plasmon resonance refractive index sensor based on ultraviolet bleached polymer waveguide,” Sens. Actuators B Chem. 244, 373–379 (2017).
[Crossref]

Yokoi, S.

Zhang, D.

L. Ji, X. Sun, G. He, Y. Liu, X. Wang, Y. Yi, C. Chen, F. Wang, and D. Zhang, “Surface plasmon resonance refractive index sensor based on ultraviolet bleached polymer waveguide,” Sens. Actuators B Chem. 244, 373–379 (2017).
[Crossref]

Zhang, J.

Zhang, Y.

Y. Zhang, H. Wang, Y. Wu, M. Tamamitsu, and A. Ozcan, “Edge sparsity criterion for robust holographic autofocusing,” Opt. Lett. 42(19), 3824–3827 (2017).
[Crossref] [PubMed]

W. Luo, Y. Zhang, A. Feizi, Z. Göröcs, and A. Ozcan, “Pixel super-resolution using wavelength scanning,” Light Sci. Appl. 5(4), e16060 (2016).
[Crossref] [PubMed]

Y. Zhang, Y. Wu, Y. Zhang, and A. Ozcan, “Color calibration and fusion of lens-free and mobile-phone microscopy images for high-resolution and accurate color reproduction,” Sci. Rep. 6(1), 27811 (2016).
[Crossref] [PubMed]

Y. Zhang, Y. Wu, Y. Zhang, and A. Ozcan, “Color calibration and fusion of lens-free and mobile-phone microscopy images for high-resolution and accurate color reproduction,” Sci. Rep. 6(1), 27811 (2016).
[Crossref] [PubMed]

Y. Zhang, S. Y. C. Lee, Y. Zhang, D. Furst, J. Fitzgerald, and A. Ozcan, “Wide-field imaging of birefringent synovial fluid crystals using lens-free polarized microscopy for gout diagnosis,” Sci. Rep. 6(1), 28793 (2016).
[Crossref] [PubMed]

Y. Zhang, S. Y. C. Lee, Y. Zhang, D. Furst, J. Fitzgerald, and A. Ozcan, “Wide-field imaging of birefringent synovial fluid crystals using lens-free polarized microscopy for gout diagnosis,” Sci. Rep. 6(1), 28793 (2016).
[Crossref] [PubMed]

W. Luo, A. Greenbaum, Y. Zhang, and A. Ozcan, “Synthetic aperture-based on-chip microscopy,” Light Sci. Appl. 4(3), e261 (2015).
[Crossref]

Zheng, J.

Zuo, C.

Am. J. Enol. Vitic. (1)

F. Rogerson and C. Symington, “A method for the estimation of alcohol in fortified wines using hydrometer Baume and refractometer Brix,” Am. J. Enol. Vitic. 57, 486–490 (2006).

Anal. Chem. (1)

C. R. Parkerson, “Determination of Saturation Temperatures of Inorganic Salt Solutions. Refractive Index Measurements,” Anal. Chem. 23(4), 610–613 (1951).
[Crossref]

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Appl. Surf. Sci. (1)

M. Stchakovsky, Y. Battie, and A. E. Naciri, “An original method to determine complex refractive index of liquids by spectroscopic ellipsometry and illustrated applications,” Appl. Surf. Sci. 421, 802–806 (2017).
[Crossref]

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J. Chem. Eng. Data (2)

C. Y. Tan and Y. X. Huang, “Dependence of Refractive Index on Concentration and Temperature in Electrolyte Solution, Polar Solution, Nonpolar Solution, and Protein Solution,” J. Chem. Eng. Data 60(10), 2827–2833 (2015).
[Crossref]

M. Yahya and M. Z. Saghir, “Prediction and Experimental Measurement of Refractive Index in Ternary Hydrocarbon Mixtures,” J. Chem. Eng. Data 60(8), 2329–2342 (2015).
[Crossref]

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Light Sci. Appl. (2)

W. Luo, A. Greenbaum, Y. Zhang, and A. Ozcan, “Synthetic aperture-based on-chip microscopy,” Light Sci. Appl. 4(3), e261 (2015).
[Crossref]

W. Luo, Y. Zhang, A. Feizi, Z. Göröcs, and A. Ozcan, “Pixel super-resolution using wavelength scanning,” Light Sci. Appl. 5(4), e16060 (2016).
[Crossref] [PubMed]

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[Crossref]

Opt. Express (6)

Opt. Lett. (6)

Optica (1)

Optik (Stuttg.) (1)

M. L. Dongare, P. B. Buchade, and A. D. Shaligram, “Refractive index based optical Brix measurement technique with equilateral angle prism for sugar and Allied Industries,” Optik (Stuttg.) 126(20), 2383–2385 (2015).
[Crossref]

Sci. Rep. (2)

Y. Zhang, S. Y. C. Lee, Y. Zhang, D. Furst, J. Fitzgerald, and A. Ozcan, “Wide-field imaging of birefringent synovial fluid crystals using lens-free polarized microscopy for gout diagnosis,” Sci. Rep. 6(1), 28793 (2016).
[Crossref] [PubMed]

Y. Zhang, Y. Wu, Y. Zhang, and A. Ozcan, “Color calibration and fusion of lens-free and mobile-phone microscopy images for high-resolution and accurate color reproduction,” Sci. Rep. 6(1), 27811 (2016).
[Crossref] [PubMed]

Sens. Actuators A Phys. (1)

C. Prokop, N. Irmler, B. Laegel, S. Wolff, A. Mitchell, and C. Karnutsch, “Optofluidic refractive index sensor based on air-suspended SU-8 grating couplers,” Sens. Actuators A Phys. 263, 439–444 (2017).
[Crossref]

Sens. Actuators B Chem. (2)

L. Ji, X. Sun, G. He, Y. Liu, X. Wang, Y. Yi, C. Chen, F. Wang, and D. Zhang, “Surface plasmon resonance refractive index sensor based on ultraviolet bleached polymer waveguide,” Sens. Actuators B Chem. 244, 373–379 (2017).
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https://www.amazon.com/Azzota-AR-1-Abb é-Monocular-Refractometer/.

M. Tamamitsu, Y. Zhang, H. Wang, Y. Wu, and A. Ozcan, “Comparison of Gini index and Tamura coefficient for holographic autofocusing based on the edge sparsity of the complex optical wavefront,” arXiv:1708.08055 [physics.optics] (2017).

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https://www.zemax.com/ .

http://www.cargille.com/immeroilspecs.shtml .

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Figures (6)

Fig. 1
Fig. 1 Schematic of scalar wave propagation.
Fig. 2
Fig. 2 Working principle of optical refractometry using lensless in-line holography and holographic autofocusing.
Fig. 3
Fig. 3 A custom-fabricated device to measure the RI of solids. RI measurement of a ZnSe plate is demonstrated here. (a) Photograph of our device. (b) Schematic side view of the inset in (a).
Fig. 4
Fig. 4 Experimental RI measurement of a ZnSe plate sample. (a-c) The acquired hologram and its autofocusing result before inserting the ZnSe plate between the USAF-1951 target and the CMOS image sensor. (d-f) The hologram and its autofocusing result after a ZnSe plate is inserted between the USAF-1951 target and the CMOS image sensor. (a) Full field-of-view (FOV) hologram and a zoom-in view of the high-resolution area of the USAF-1951 target (inset), without the ZnSe plate. (b) GoG autofocusing curve as a function of z. The discrete points in the curve represent the evaluated z-distances by the search algorithm (Section 2.2). (c) The hologram back-propagated to the z-distance determined by the autofocusing algorithm. (d) The hologram recorded after the ZnSe plate is inserted. Interference pattern is visible due to slightly nonparallel front and back surfaces of the ZnSe plate. (e, f) Autofocusing result and the back-propagation of the hologram in (d).
Fig. 5
Fig. 5 Photograph and schematic of a portable device for measuring the RI of liquid samples based on lensless holographic on-chip imaging and autofocusing. (a) Photograph of our portable device. (b) 3D design schematic. (c) Zoom-in top-view of the device excluding the laser diode used for illumination.
Fig. 6
Fig. 6 Experimental results for measuring the RI of liquid sample. (a-c) Hologram (left) and autofocus curve (right) when the chamber is with (a) air; (b) DI water; and (c) immersion oil to be tested.

Tables (2)

Tables Icon

Table 1 Estimated uncertainties in the measured parameters (solid sample).

Tables Icon

Table 2 Estimated uncertainties in measured parameters (liquid sample).

Equations (29)

Equations on this page are rendered with MathJax. Learn more.

A( f x , f y ;z )= U( x,y;z ) exp[ j2π( f x x+ f y y ) ]dxdy.
A( f x , f y ;z )=A( f x , f y ;0 )H( f x , f y ;z ).
H( f x , f y ;z )={ exp[ j2π n λ 0 z 1 ( λ 0 f x n ) 2 ( λ 0 f y n ) 2 ], f x 2 + f y 2 f cut-off 0, others ,
f cut-off = n λ 0 .
H( f x , f y ;z )exp( j2π nz λ 0 )exp[ jπ λ 0 z n ( f x 2 + f y 2 ) ].
H ˜ ( f x , f y ;z )=exp[ jπ λ 0 z n ( f x 2 + f y 2 ) ].
l E = z 1 z 2 1 n( z ) dz .
GoG( U )=Gini( | U | ),
Gini( C )=12 k=1 N a [ k ] sum( C ) ( Nk+0.5 N ) ,
z AF = argmax z { GoG[ (G;z) ] },
φ= π λ 0 R [ ( x x c ) 2 + ( y y c ) 2 ],
l E,1 = l E,0 d n a + d n x ,
n x = d l E,1 l E,0 + d n a .
σ( n x )= ( n x d δd ) 2 + ( n x l E,0 δ l E,0 ) 2 + ( n x l E,1 δ l E,1 ) 2 + ( n x n a δ n a ) 2 ,
n x d = l E,1 l E,0 ( l E,1 l E,0 + d n a ) 2 = n a 2 ( l E,1 l E,0 ) ( n a l E,1 n a l E,0 +d ) 2 ,
n x l E,0 = d ( l E,1 l E,0 + d n a ) 2 = n a 2 d ( n a l E,1 n a l E,0 +d ) 2 ,
n x l E,1 = d ( l E,1 l E,0 + d n a ) 2 = n a 2 d ( n a l E,1 n a l E,0 +d ) 2 ,
n x n a = d 2 n a 2 ( l E,1 l E,0 + d n a ) 2 = d 2 ( n a l E,1 n a l E,0 +d ) 2 ,
n x = n a n w l E,0 n a n w l E,1 n w l E,2 n a l E,2 + n a l E,0 n w l E,1 ,
σ( n x )= ( n x l E,0 δ l E,0 ) 2 + ( n x l E,1 δ l E,1 ) 2 + ( n x l E,2 δ l E,2 ) 2 + ( n x n a δ n a ) 2 + ( n x n w δ n w ) 2 ,
n x l E, 0 = n a n w 2 l E,2 n a 2 n w l E,2 n a n w 2 l E,1 + n a 2 n w l E,1 ( n w l E,2 n a l E,2 + n a l E,0 n w l E,1 ) 2 ,
n x l E, 1 = n a 2 n w l E,2 n a 2 n w l E,0 + n a n w 2 l E,0 n a n w 2 l E,2 ( n w l E,2 n a l E,2 + n a l E,0 n w l E,1 ) 2 ,
n x l E, 2 = n a 2 n w l E,0 n a 2 n w l E,1 n a n w 2 l E,0 + n a n w 2 l E,1 ( n w l E,2 n a l E,2 + n a l E,0 n w l E,1 ) 2 ,
n x n a = n w 2 l E,0 l E,2 n w 2 l E,1 l E,2 n w 2 l E,0 l E,1 + n w 2 l E,1 2 ( n w l E,2 n a l E,2 + n a l E,0 n w l E,1 ) 2 ,
n x n w = n a 2 l E,0 2 + n a 2 l E,1 l E,2 n a 2 l E,0 l E,2 n a 2 l E,0 l E,1 ( n w l E,2 n a l E,2 + n a l E,0 n w l E,1 ) 2 .
l E,0 = l E,S + t n a ,
l E,1 = l E,S + t n w ,
l E,2 = l E,S + t n x .
t= ( l E,0 l E,1 ) n a n w n w n a .

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