Abstract

A comparison between the commonly used absorption spectrophotometry and a more recent approach known as structured laser illumination planar imaging (SLIPI) is presented for the characterization of scattering and absorbing liquids. Water solutions of milk and coffee are, respectively, investigated for 10 different levels of turbidity. For the milk solutions, scattering is the dominant process, while the coffee solutions have a high level of absorption. Measurements of the extinction coefficient are performed at both λ=450  nm and λ=638  nm and the ratio of their values has been extracted. We show that the turbidity limit of valid transmission measurements is reached at an optical depth of OD2.4, corresponding here to an extinction coefficient of μe=0.60  mm1 when using a modern absorption spectrometer having a spatial Fourier filter prior to detection. Above this value, errors are induced due to the contribution of scattered and multiply scattered photons reaching the detector. On the contrary, the SLIPI measurements were found to be very reliable, even for an extinction coefficient three times as high, where μe=1.80  mm1. This improvement is due to the capability of the technique in efficiently suppressing the contribution from multiple light scattering.

© 2017 Optical Society of America

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References

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    [Crossref]
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    [Crossref]
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    [Crossref]
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    [Crossref]

2016 (2)

2014 (2)

2013 (2)

T. Kruatian and K. Jitmanee, “Simple spectrophotometric method for determination of iodine value of vegetable oils,” Chiang Mei J. Sci. 3, 419–426 (2013).

W. Xu, T.-H. Kim, D. Zhai, J. C. Er, L. Zhang, A. A. Kale, B. K. Agrawalla, Y.-K. Cho, and Y.-T. Chang, “Make caffeine visible: a fluorescent caffeine “traffic light” detector,” Sci. Rep. 3, 2255 (2013).
[Crossref]

2012 (3)

E. Kristensson, E. Berrocal, and M. Aldén, “Quantitative 3D imaging of scattering media using structured illumination and computed tomography,” Opt. Express 20, 14437 (2012).
[Crossref]

E. Berrocal, J. Johnsson, E. Kristensson, and M. Aldén, “Single scattering detection in turbid media using single-phase structured illumination filtering,” J. Eur. Opt. Soc. 7, 12015 (2012).

F. Foschum and A. Kienle, “Broadband absorption spectroscopy of turbid media using a dual step steady-state method,” J. Biomed. Opt. 17, 037009 (2012).
[Crossref]

2011 (1)

2010 (2)

O. Ménard, S. Ahmad, F. Rousseau, V. Briard-Bion, F. Gaucheron, and C. Lopez, “Buffalo vs. cow milk fat globules: size distribution, zeta-potential, compositions in total fatty acids and in polar lipids from the milk fat globule membrane,” Food Chem. 120, 544–551 (2010).
[Crossref]

A. Bose, P. P. Dash, and M. K. Sahoo, “Simple spectrophotometric methods for estimation of aceclofenac from bulk and formulations,” Pharm. Methods 1, 57–60 (2010).

2008 (1)

2007 (1)

2004 (1)

S. Mujumdar and H. Ramachandran, “Imaging through turbid media using polarization modulation: dependence on scattering anisotropy,” Opt. Commun. 241, 1–9 (2004).
[Crossref]

2000 (1)

1998 (1)

H. Ramachandran and A. Narayanan, “Two-dimensional imaging through turbid media using a continuous wave light source,” Opt. Commun. 154, 255–260 (1998).
[Crossref]

1993 (1)

1991 (1)

1982 (1)

M. L. Meade, “Advances in lock-in amplifiers,” J. Phys. E 15, 395–403 (1982).
[Crossref]

1836 (1)

H. F. Talbot, “Facts relating to optical science. No. IV,” Philos. Mag. 9(56), 401–407 (1836).

Abou Nada, F.

Agrawalla, B. K.

W. Xu, T.-H. Kim, D. Zhai, J. C. Er, L. Zhang, A. A. Kale, B. K. Agrawalla, Y.-K. Cho, and Y.-T. Chang, “Make caffeine visible: a fluorescent caffeine “traffic light” detector,” Sci. Rep. 3, 2255 (2013).
[Crossref]

Ahmad, S.

O. Ménard, S. Ahmad, F. Rousseau, V. Briard-Bion, F. Gaucheron, and C. Lopez, “Buffalo vs. cow milk fat globules: size distribution, zeta-potential, compositions in total fatty acids and in polar lipids from the milk fat globule membrane,” Food Chem. 120, 544–551 (2010).
[Crossref]

Aldén, M.

Alfano, R. R.

Araneo, L.

Bengtsson, P.-E.

Berger, A. J.

Berrocal, E.

E. Berrocal, S.-G. Pettersson, and E. Kristensson, “High-contrast imaging through scattering media using structured illumination and Fourier filtering,” Opt. Lett. 41, 5612–5615 (2016).
[Crossref]

Y. N. Mishra, F. Abou Nada, S. Polster, E. Kristensson, and E. Berrocal, “Thermometry in aqueous solutions and sprays using two-color LIF and structured illumination,” Opt. Express 24, 4949–4963 (2016).
[Crossref]

E. Kristensson, E. Berrocal, and M. Aldén, “Two-pulse structured illumination imaging,” Opt. Lett. 39, 2584–2587 (2014).
[Crossref]

E. Kristensson, J. Bood, M. Aldén, E. Nordström, J. Zhu, S. Huldt, P.-E. Bengtsson, H. Nilsson, E. Berrocal, and A. Ehn, “Stray light suppression in spectroscopy using periodic shadowing,” Opt. Express 22, 7711–7721 (2014).
[Crossref]

E. Berrocal, J. Johnsson, E. Kristensson, and M. Aldén, “Single scattering detection in turbid media using single-phase structured illumination filtering,” J. Eur. Opt. Soc. 7, 12015 (2012).

E. Kristensson, E. Berrocal, and M. Aldén, “Quantitative 3D imaging of scattering media using structured illumination and computed tomography,” Opt. Express 20, 14437 (2012).
[Crossref]

E. Kristensson, L. Araneo, E. Berrocal, J. Manin, M. Richter, M. Aldén, and M. Linne, “Analysis of multiple scattering suppression using structured laser illumination planar imaging in scattering and fluorescing media,” Opt. Express 19, 13647 (2011).
[Crossref]

E. Berrocal, E. Kristensson, M. Richter, M. Linne, and M. Aldén, “Application of structured illumination for multiple scattering suppression in planar laser imaging of dense sprays,” Opt. Express 16, 17870 (2008).
[Crossref]

E. Berrocal, D. L. Sedarsky, M. E. Paciaroni, I. V. Meglinski, and M. A. Linne, “Laser light scattering in turbid media. Part I: experimental and simulated results for the spatial intensity distribution,” Opt. Express 15, 10649 (2007).
[Crossref]

Bevilacqua, F.

Bood, J.

Bose, A.

A. Bose, P. P. Dash, and M. K. Sahoo, “Simple spectrophotometric methods for estimation of aceclofenac from bulk and formulations,” Pharm. Methods 1, 57–60 (2010).

Briard-Bion, V.

O. Ménard, S. Ahmad, F. Rousseau, V. Briard-Bion, F. Gaucheron, and C. Lopez, “Buffalo vs. cow milk fat globules: size distribution, zeta-potential, compositions in total fatty acids and in polar lipids from the milk fat globule membrane,” Food Chem. 120, 544–551 (2010).
[Crossref]

Cerussi, A. E.

Chang, Y.-T.

W. Xu, T.-H. Kim, D. Zhai, J. C. Er, L. Zhang, A. A. Kale, B. K. Agrawalla, Y.-K. Cho, and Y.-T. Chang, “Make caffeine visible: a fluorescent caffeine “traffic light” detector,” Sci. Rep. 3, 2255 (2013).
[Crossref]

Cho, Y.-K.

W. Xu, T.-H. Kim, D. Zhai, J. C. Er, L. Zhang, A. A. Kale, B. K. Agrawalla, Y.-K. Cho, and Y.-T. Chang, “Make caffeine visible: a fluorescent caffeine “traffic light” detector,” Sci. Rep. 3, 2255 (2013).
[Crossref]

Dai, H.

Dash, P. P.

A. Bose, P. P. Dash, and M. K. Sahoo, “Simple spectrophotometric methods for estimation of aceclofenac from bulk and formulations,” Pharm. Methods 1, 57–60 (2010).

Ehn, A.

Er, J. C.

W. Xu, T.-H. Kim, D. Zhai, J. C. Er, L. Zhang, A. A. Kale, B. K. Agrawalla, Y.-K. Cho, and Y.-T. Chang, “Make caffeine visible: a fluorescent caffeine “traffic light” detector,” Sci. Rep. 3, 2255 (2013).
[Crossref]

Foschum, F.

F. Foschum and A. Kienle, “Broadband absorption spectroscopy of turbid media using a dual step steady-state method,” J. Biomed. Opt. 17, 037009 (2012).
[Crossref]

Gaucheron, F.

O. Ménard, S. Ahmad, F. Rousseau, V. Briard-Bion, F. Gaucheron, and C. Lopez, “Buffalo vs. cow milk fat globules: size distribution, zeta-potential, compositions in total fatty acids and in polar lipids from the milk fat globule membrane,” Food Chem. 120, 544–551 (2010).
[Crossref]

Ho, P. P.

Huldt, S.

Jakubowski, D.

Jitmanee, K.

T. Kruatian and K. Jitmanee, “Simple spectrophotometric method for determination of iodine value of vegetable oils,” Chiang Mei J. Sci. 3, 419–426 (2013).

Johnsson, J.

E. Berrocal, J. Johnsson, E. Kristensson, and M. Aldén, “Single scattering detection in turbid media using single-phase structured illumination filtering,” J. Eur. Opt. Soc. 7, 12015 (2012).

Kale, A. A.

W. Xu, T.-H. Kim, D. Zhai, J. C. Er, L. Zhang, A. A. Kale, B. K. Agrawalla, Y.-K. Cho, and Y.-T. Chang, “Make caffeine visible: a fluorescent caffeine “traffic light” detector,” Sci. Rep. 3, 2255 (2013).
[Crossref]

Kienle, A.

F. Foschum and A. Kienle, “Broadband absorption spectroscopy of turbid media using a dual step steady-state method,” J. Biomed. Opt. 17, 037009 (2012).
[Crossref]

Kim, T.-H.

W. Xu, T.-H. Kim, D. Zhai, J. C. Er, L. Zhang, A. A. Kale, B. K. Agrawalla, Y.-K. Cho, and Y.-T. Chang, “Make caffeine visible: a fluorescent caffeine “traffic light” detector,” Sci. Rep. 3, 2255 (2013).
[Crossref]

Kristensson, E.

E. Berrocal, S.-G. Pettersson, and E. Kristensson, “High-contrast imaging through scattering media using structured illumination and Fourier filtering,” Opt. Lett. 41, 5612–5615 (2016).
[Crossref]

Y. N. Mishra, F. Abou Nada, S. Polster, E. Kristensson, and E. Berrocal, “Thermometry in aqueous solutions and sprays using two-color LIF and structured illumination,” Opt. Express 24, 4949–4963 (2016).
[Crossref]

E. Kristensson, E. Berrocal, and M. Aldén, “Two-pulse structured illumination imaging,” Opt. Lett. 39, 2584–2587 (2014).
[Crossref]

E. Kristensson, J. Bood, M. Aldén, E. Nordström, J. Zhu, S. Huldt, P.-E. Bengtsson, H. Nilsson, E. Berrocal, and A. Ehn, “Stray light suppression in spectroscopy using periodic shadowing,” Opt. Express 22, 7711–7721 (2014).
[Crossref]

E. Berrocal, J. Johnsson, E. Kristensson, and M. Aldén, “Single scattering detection in turbid media using single-phase structured illumination filtering,” J. Eur. Opt. Soc. 7, 12015 (2012).

E. Kristensson, E. Berrocal, and M. Aldén, “Quantitative 3D imaging of scattering media using structured illumination and computed tomography,” Opt. Express 20, 14437 (2012).
[Crossref]

E. Kristensson, L. Araneo, E. Berrocal, J. Manin, M. Richter, M. Aldén, and M. Linne, “Analysis of multiple scattering suppression using structured laser illumination planar imaging in scattering and fluorescing media,” Opt. Express 19, 13647 (2011).
[Crossref]

E. Berrocal, E. Kristensson, M. Richter, M. Linne, and M. Aldén, “Application of structured illumination for multiple scattering suppression in planar laser imaging of dense sprays,” Opt. Express 16, 17870 (2008).
[Crossref]

Kruatian, T.

T. Kruatian and K. Jitmanee, “Simple spectrophotometric method for determination of iodine value of vegetable oils,” Chiang Mei J. Sci. 3, 419–426 (2013).

Liang, X.

Linne, M.

Linne, M. A.

Liu, F.

Lopez, C.

O. Ménard, S. Ahmad, F. Rousseau, V. Briard-Bion, F. Gaucheron, and C. Lopez, “Buffalo vs. cow milk fat globules: size distribution, zeta-potential, compositions in total fatty acids and in polar lipids from the milk fat globule membrane,” Food Chem. 120, 544–551 (2010).
[Crossref]

Manin, J.

Meade, M. L.

M. L. Meade, “Advances in lock-in amplifiers,” J. Phys. E 15, 395–403 (1982).
[Crossref]

Meglinski, I. V.

Ménard, O.

O. Ménard, S. Ahmad, F. Rousseau, V. Briard-Bion, F. Gaucheron, and C. Lopez, “Buffalo vs. cow milk fat globules: size distribution, zeta-potential, compositions in total fatty acids and in polar lipids from the milk fat globule membrane,” Food Chem. 120, 544–551 (2010).
[Crossref]

Mishra, Y. N.

Mujumdar, S.

S. Mujumdar and H. Ramachandran, “Imaging through turbid media using polarization modulation: dependence on scattering anisotropy,” Opt. Commun. 241, 1–9 (2004).
[Crossref]

Mullins, C. M.

C. M. Mullins, Cardiac Catheterization in Congenital Heart Disease: Pediatric and Adult (Blackwell Futura, 2006), pp. 296–297.

Narayanan, A.

H. Ramachandran and A. Narayanan, “Two-dimensional imaging through turbid media using a continuous wave light source,” Opt. Commun. 154, 255–260 (1998).
[Crossref]

Nilsson, H.

Nordström, E.

Paciaroni, M. E.

Pettersson, S.-G.

Polster, S.

Ramachandran, H.

S. Mujumdar and H. Ramachandran, “Imaging through turbid media using polarization modulation: dependence on scattering anisotropy,” Opt. Commun. 241, 1–9 (2004).
[Crossref]

H. Ramachandran and A. Narayanan, “Two-dimensional imaging through turbid media using a continuous wave light source,” Opt. Commun. 154, 255–260 (1998).
[Crossref]

Richter, M.

Rousseau, F.

O. Ménard, S. Ahmad, F. Rousseau, V. Briard-Bion, F. Gaucheron, and C. Lopez, “Buffalo vs. cow milk fat globules: size distribution, zeta-potential, compositions in total fatty acids and in polar lipids from the milk fat globule membrane,” Food Chem. 120, 544–551 (2010).
[Crossref]

Sahoo, M. K.

A. Bose, P. P. Dash, and M. K. Sahoo, “Simple spectrophotometric methods for estimation of aceclofenac from bulk and formulations,” Pharm. Methods 1, 57–60 (2010).

Sedarsky, D. L.

Talbot, H. F.

H. F. Talbot, “Facts relating to optical science. No. IV,” Philos. Mag. 9(56), 401–407 (1836).

Tromberg, B. J.

Wang, C. L.

Xu, W.

W. Xu, T.-H. Kim, D. Zhai, J. C. Er, L. Zhang, A. A. Kale, B. K. Agrawalla, Y.-K. Cho, and Y.-T. Chang, “Make caffeine visible: a fluorescent caffeine “traffic light” detector,” Sci. Rep. 3, 2255 (2013).
[Crossref]

Yoo, K. M.

Zhai, D.

W. Xu, T.-H. Kim, D. Zhai, J. C. Er, L. Zhang, A. A. Kale, B. K. Agrawalla, Y.-K. Cho, and Y.-T. Chang, “Make caffeine visible: a fluorescent caffeine “traffic light” detector,” Sci. Rep. 3, 2255 (2013).
[Crossref]

Zhang, L.

W. Xu, T.-H. Kim, D. Zhai, J. C. Er, L. Zhang, A. A. Kale, B. K. Agrawalla, Y.-K. Cho, and Y.-T. Chang, “Make caffeine visible: a fluorescent caffeine “traffic light” detector,” Sci. Rep. 3, 2255 (2013).
[Crossref]

Zhu, J.

Appl. Opt. (1)

Chiang Mei J. Sci. (1)

T. Kruatian and K. Jitmanee, “Simple spectrophotometric method for determination of iodine value of vegetable oils,” Chiang Mei J. Sci. 3, 419–426 (2013).

Food Chem. (1)

O. Ménard, S. Ahmad, F. Rousseau, V. Briard-Bion, F. Gaucheron, and C. Lopez, “Buffalo vs. cow milk fat globules: size distribution, zeta-potential, compositions in total fatty acids and in polar lipids from the milk fat globule membrane,” Food Chem. 120, 544–551 (2010).
[Crossref]

J. Biomed. Opt. (1)

F. Foschum and A. Kienle, “Broadband absorption spectroscopy of turbid media using a dual step steady-state method,” J. Biomed. Opt. 17, 037009 (2012).
[Crossref]

J. Eur. Opt. Soc. (1)

E. Berrocal, J. Johnsson, E. Kristensson, and M. Aldén, “Single scattering detection in turbid media using single-phase structured illumination filtering,” J. Eur. Opt. Soc. 7, 12015 (2012).

J. Phys. E (1)

M. L. Meade, “Advances in lock-in amplifiers,” J. Phys. E 15, 395–403 (1982).
[Crossref]

Opt. Commun. (2)

H. Ramachandran and A. Narayanan, “Two-dimensional imaging through turbid media using a continuous wave light source,” Opt. Commun. 154, 255–260 (1998).
[Crossref]

S. Mujumdar and H. Ramachandran, “Imaging through turbid media using polarization modulation: dependence on scattering anisotropy,” Opt. Commun. 241, 1–9 (2004).
[Crossref]

Opt. Express (6)

Opt. Lett. (4)

Pharm. Methods (1)

A. Bose, P. P. Dash, and M. K. Sahoo, “Simple spectrophotometric methods for estimation of aceclofenac from bulk and formulations,” Pharm. Methods 1, 57–60 (2010).

Philos. Mag. (1)

H. F. Talbot, “Facts relating to optical science. No. IV,” Philos. Mag. 9(56), 401–407 (1836).

Sci. Rep. (1)

W. Xu, T.-H. Kim, D. Zhai, J. C. Er, L. Zhang, A. A. Kale, B. K. Agrawalla, Y.-K. Cho, and Y.-T. Chang, “Make caffeine visible: a fluorescent caffeine “traffic light” detector,” Sci. Rep. 3, 2255 (2013).
[Crossref]

Other (1)

C. M. Mullins, Cardiac Catheterization in Congenital Heart Disease: Pediatric and Adult (Blackwell Futura, 2006), pp. 296–297.

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Figures (13)

Fig. 1.
Fig. 1.

Classification of absorbing and scattering media. For transmission measurements (e.g., absorption spectrophotometry), the optimum situation is to probe an optically dilute absorbing solution. However, an optically dense scattering medium will be very challenging to probe as undesired scattered light will be detected.

Fig. 2.
Fig. 2.

Illustration adapted from Ocean Optics of the absorption spectrophotometer. A zoomed view of the optical arrangement around the cuvette is also given. White light exits the first optical fiber at the focus of a collimating lens. The collimated white beam crosses the turbid solution and is collected using another lens, focusing it into a second optical fiber. This light is then spectrally dispersed and analyzed using the USB4000-FL spectrometer from Ocean Optics.

Fig. 3.
Fig. 3.

Spectrum of the white LED light used in the experiment. This spectrum has been recorded with 40 ms exposure time and serves as the reference. The 450 nm and 638 nm wavelengths corresponding to the SLIPI illumination wavelengths are indicated on the spectrum.

Fig. 4.
Fig. 4.

Principle of single-phase SLIPI. The example shows the signal from a structured laser sheet with cross sections extracted from two different depths, marked as A and B. Notice the decrease in amplitude from column A to B. The 1D Fourier transforms of curves A and B show the reduction in strength of the first-order peak (modulation frequency). This frequency is then isolated using frequency filtering (red area) after applying the lock-in algorithm. Finally, the exponential decay is revealed, as shown in the SLIPI image and related curve IS.

Fig. 5.
Fig. 5.

SLIPI optical setup. After expanding the incident laser beam, a light sheet is formed by using a cylindrical lens focusing the beam into the cuvette. The light sheet is modulated just prior to entering the cuvette containing the turbid liquid by a Ronchi grating of 2  lp/mm frequency. The images are recorded using an EM-CCD camera.

Fig. 6.
Fig. 6.

Photographs of the samples prepared at various dilution ratios for the milk and the coffee. The increase in turbidity from right to left is apparent, especially in the case of the coffee solutions. The corresponding dilution procedure of each solution is provided in the table.

Fig. 7.
Fig. 7.

Absorbance spectra of the milk solutions in (a) and the coffee solutions in (b) measured using absorption spectrophotometry. The increase of the absorbance with concentration is clearly seen. It can also be observed that the absorbance gives an equal value at high concentration and for the “blue” wavelength range due to too low of a signal-to-noise ratio in these conditions.

Fig. 8.
Fig. 8.

Images of the structured light sheet crossing the cuvette at increased milk concentration. The corresponding SLIPI images are given on the right-hand side. As milk highly scatters light, blurring effects due to multiple light scattering are apparent on the modulated images. By suppressing this unwanted contribution and demodulating the signal, the SLIPI images are obtained, where the light extinction through the cuvette is clearly visible. By analyzing those images and fitting an exponential decay, the extinction coefficient can be directly deduced.

Fig. 9.
Fig. 9.

Images of the structured light sheet crossing the cuvette at increased coffee concentrations. The corresponding SLIPI images are given on the right-hand side. As coffee is mostly absorbing, the blurring effects due to multiple scattering are less apparent here than for the milk case. However, there is still some remaining undesired scattered light that must be suppressed using SLIPI. Thus, the resulting SLIPI images depict the correct light extinction, where an exponential fitting of the intensity decay provides the corresponding extinction coefficient.

Fig. 10.
Fig. 10.

Curves obtained by vertically integrating the SLIPI image results of the milk solutions for 450 nm illumination wavelength in (a) and 638 nm in (b). The exponential decay of the light intensity as a function of distance through the cuvette is obtained here, and the extinction coefficient has been deduced from those decays.

Fig. 11.
Fig. 11.

Curves obtained by vertically integrating the SLIPI image results of the coffee solutions for 450 nm illumination wavelength in (a) and 638 nm in (b). The exponential decay of the light intensity as a function of distance through the cuvette is obtained here, and the extinction coefficient has been deduced from those decays.

Fig. 12.
Fig. 12.

Extinction coefficient results as a function of concentration for (a) milk and (b) coffee solutions. The SLIPI results show good linearity, while the absorption measurements show loose linearity.

Fig. 13.
Fig. 13.

Ratio of the extinction coefficients, R=μe(450nm)/μe(638nm), as a function of concentration. The SLIPI results show, as expected, a constant ratio for both milk and coffee, where Rmilk=1.9 and Rcoffee=2.7.

Equations (13)

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

T=It/I0=eμe·L=eOD,
μe=N·(σa+σs).
μe=ln(T)/L.
lfp¯=1/μe.
OD=L/lfp¯.
A=OD/ln(10)=log10T.
I(x)=ISsin(2πνx+ϕ)+IMS(x),
R1(x)=sin(2πνx)andR2(x)=cos(2πνx).
I1(x)=12IS(cos(ϕ)cos(4πνx+ϕ))+IMSsin(2πνx),
I2(x)=12IS(sin(ϕ)+sin(4πνx+ϕ))+IMScos(2πνx).
I˜1(x)=12IS˜cos(ϕ)andI˜2(x)=12IS˜sin(ϕ),
IS˜=2(I˜1)2+(I˜2)2.
μe=A·ln(10)/L,

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