Archive: August, 2013

T. Kim, R. Zhu, T. Nguyen, R. Zhou, C. Edwards, L. Goddard and G. Popescu, Deterministic signal associated with a random field, Opt.Exp., 21(18), 20806-20820 (2013)

Posted on 08/30/13 by Taewoo

PDF Link Stochastic fields do not generally possess a Fourier transform. This makes the second-order statistics calculation very difficult, as it requires solving a fourth-order stochastic wave equation. This problem was alleviated by Wolf who introduced the coherent mode decomposition and, as a result, space-frequency statistics propagation of wide-sense stationary fields. In this paper we […]

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T. Nguyen, and G. Popescu, Spatial Light Interference Microscopy (SLIM) using twisted-nematic liquid-crystal modulation, Biomed. Opt. Exp., 4(9), 1571-1583 (2013)

Posted on 08/26/13 by Tan Nguyen

PDF Link  We report the use of a twisted nematic liquid-crystal spatial light modulator (TNLC-SLM) for quantitative phase imaging. The experimental setup is a new implementation of the SLIM principle, which is a phase shifting, white light method for quantitative phase imaging. The approach is based on switching between the phase and amplitude modulation modes […]

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R. Zhou, C. Edwards, A. Arbabi, G. Popescu and L. Goddard, Detecting 20 nm wide defects in large area nanopatterns using optical interferometric microscopy, Nano Letters 13 (8), 3716-3721 (2013).

Posted on 08/15/13 by Taewoo

PDF Link Due to the diffraction limited resolution and the presence of speckle noise, visible laser light is generally thought to be impractical for finding deep subwavelength defects in patterned semiconductor wafers. Here, we report on a nondestructive low-noise interferometric imaging method capable of detecting nanoscale defects within a wide field of view using visible […]

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T. Kim, S. Sridharan, and G. Popescu, Gradient field microscopy of unstained specimens: reply to comment, Opt. Exp. 21 (16), 19188 (2013).

Posted on 08/05/13 by Taewoo

PDF Link We reply to the comment written by Ferrari and Ayubi on our recent paper, Kim et al. [Opt. Express, 20, 6737 (2012)]. We maintain that our use of Fourier filtering methods lead to valuable intrinsic contrast live cell imaging. Judging by their comments regarding the limit sin(x)~x, it seems that the authors overlooked […]

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