A method for enhancing contrast of reconstructed particle image

LI Zhi-bin; ZHENG Gang; ZHANG Li-xin

doi:10.3969/j.issn.1001-3806.2010.01.032

In order to improve the contrast of a reconstructed image and reduce the effect of directly transmitted light, conjugate image and defocused image on the focused image of the particle in the reconstruction of a 3-D particle digital holography,a numerical method was proposed in which the above effect can be reduced because of the subtraction of both the complex amplitudes of the particle in the focused and defocused planes. The theory of the method was presented. The simulated results and experimental examples were shown. This method is useful to slice in-line digital holograms to display only in-focus particles at a focused plane. Furthermore,in the reconstruction process,only a single hologram is needed without additional pre- or post- processing.

A method for enhancing contrast of reconstructed particle image

Corresponding author: ZHENG Gang, gangzheng@usst.edu.cn;

1. College of Optics and Electronics Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China;

2. College of Power Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China;

3. Faculty of Electric and Automatic Engineering, Shanghai University of Electric Power, Shanghai 200090, China

Received Date: 2008-10-09

Accepted Date: 2008-12-09

Available Online: 2010-01-25

Abstract: In order to improve the contrast of a reconstructed image and reduce the effect of directly transmitted light, conjugate image and defocused image on the focused image of the particle in the reconstruction of a 3-D particle digital holography,a numerical method was proposed in which the above effect can be reduced because of the subtraction of both the complex amplitudes of the particle in the focused and defocused planes. The theory of the method was presented. The simulated results and experimental examples were shown. This method is useful to slice in-line digital holograms to display only in-focus particles at a focused plane. Furthermore,in the reconstruction process,only a single hologram is needed without additional pre- or post- processing.

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Reference (17)

[1]	ADAMS M,KREIS T,JÜPTNER W.Particle analysis with digital holography[J].Proc SPIE,2000,4101:314-319.
[2]	MURATA S,YASUDA N.Potential of digital holography in particlemeasurement[J].Optics&Laser Technology,2000,32(8):567-574.
[3]	PALACIOS F,RICARDO J,PALACIOS D,et al.3-D image reconstruction of transparent microscopic objects using digital holography[J].Opt Commun,2005,248(1/3):41-50.
[4]	MALKIEL E,SHENG J,KATZ J,et al.The three-dimensional flowfield generated by a feeding calanoid copepod measured using digital holography[J].Journal of Experimental Biology,2003,206(20):3657-3666.
[5]	FUGAL J P,SHAW R A,SAW E W,et al.Airborne digital holographic system for cloud particle measurements[J].Appl Opt,2004,43(32):5987-5995.
[6]	LI Z R,YE Y,ZHENG X X,et al.Micro-jet particle field measurement using in-line Fraunhofer holography[J].Laser Technology,2004,28(1):45-47(in Chinese).
[7]	ZHANG Y M,LÜQ N,GE B Zh.Elimination of zero-order diffraction in digital off-axis holography[J].Opt Commun,2004,240(4/6):261-267.
[8]	LAI S,KING B,NEIFIELD M A.Wave front reconstruction by means of phase-shifting digital in-line holography[J].Opt Commun,2000,173(1/6):155-160.
[9]	KREIS T,JÜPTNER W.Suppression of DC term in digital holography[J].Opt Engng,1997,36(8):2357-2360.
[10]	DENIS L,FOURNIER C,FOURNEL T,et al.Twin-image noise reduction by phase retrieval in in-line digital holography[J].Proc SPIE,2005,5914:1-14.
[11]	MENG H,PAN G,PU Y,et al.Holographic particle image velocimetry:from film to digital recording[J].Measurement Science Technology,2004,15:673-685.
[12]	SHEN G X,WEI R J.Digital holography particle image velocimetry for the measurement of 3Dt-3c flows[J].Optics and Lasers in Engineering,2005,43(10):1039-1055.
[13]	FOURNIER C,DUCOTTET C,FOURNEL T.Digital holographic particle image velocimetry:3-D velocity field extraction using correlation[J].Journal of Flow Visualization&Image Processing,2004,11(1):53-72.
[14]	MALEK M,ALLANO D,COËTMELLEC S.Digital in-line hologra-phy:influence of the shadow density on particle field extraction[J].Optics Express,2004,12(10):2270-2279.
[15]	PAN G,MENG H.Digital holography of particle fields:reconstruction by use of complex amplitude[J].Appl Opt,2003,42(5):827-833.
[16]	GARCIA-SUCERQUIA J,CASTAÑEDA R.Spatial partially coherent imaging[J].Journal of Modem Optics,2002,49(13):2093-2104.
[17]	MEDINA F F,CASTANEDA R,GARCIA J.Resolution,focus depth in the Fresnel-Fraunhofer domains[J].Proc SPIE,2006,6027:1-9.

A method for enhancing contrast of reconstructed particle image

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