Publications by authors named "Hyo Mi Park"

7 Publications

  • Page 1 of 1

Motionless Polarizing Structured Illumination Microscopy.

Sensors (Basel) 2021 Apr 17;21(8). Epub 2021 Apr 17.

3D Optical Metrology Laboratory, Department of Photonic Engineering, Chosun University, 309 Pilmun-Daero, Dong-gu, Gwangju 61452, Korea.

In this investigation, we propose a motionless polarizing structured illumination microscopy as an axially sectioning and reflective-type device to measure the 3D surface profiles of specimens. Based on the spatial phase-shifting technique to obtain the visibility of the illumination pattern. Instead of using a grid, a Wollaston prism is used to generate the light pattern by the stable interference of two beams. As the polarization states of two beams are orthogonal with each other, a polarization pixelated CMOS camera can simultaneously obtain four phase-shifted patterns with the beams after passing through a quarter wave plate based on the spatial phase-shifting technique with polarization. In addition, a focus tunable lens is used to eliminate a mechanical moving part for the axial scanning of the specimen. In the experimental result, a step height sample and a concave mirror were measured with 0.05 µm and 0.2 mm repeatabilities of step height and the radius of curvature, respectively.
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http://dx.doi.org/10.3390/s21082837DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8073734PMC
April 2021

Vision chromatic confocal sensor based on a geometrical phase lens.

Appl Opt 2021 Apr;60(10):2898-2901

A vison chromatic confocal sensor used to monitor the location of a measured point is proposed and experimentally verified. To induce chromatic aberration of the sensor, a geometrical phase lens is adopted and is also used as a beam splitter. Near the geometrical phase lens, a focused beam is used for the chromatic confocal sensor, and a diverging beam is used for imaging of the specimen. In the experiment, the performance of the proposed system was verified with regard to distance sensing and the capability of monitoring the measured points. The measuring range was approximately 10 mm, and the repeatability was 0.4 µm when a geometrical phase lens with a 75 mm focal length was used.
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http://dx.doi.org/10.1364/AO.423339DOI Listing
April 2021

Spectrally resolved polarizing interferometer for single-shot line profiling.

Appl Opt 2020 Nov;59(32):10107-10112

In this investigation, we describe a spectrally resolved polarizing interferometer to modify the typical spectrally resolved interferometer based on the Fourier method, which has a dead zone caused by the minimum measurable range. By use of a polarization pixelated CMOS camera, which enables us to obtain spatially phase-shifted spectral interferograms, the spectral phase can be extracted with a single image, and the proposed interferometer can obtain a line profile of a specimen at once. By the nature of phase-shifting technique, moreover, the directions of the measured distances can be identified, and the measuring range is extended to twice that of the typical spectrally resolved interferometer. In the experimental results, the measuring range was 104 µm, and the capability to obtain a line profile of a specimen with a single image was confirmed. For 3D surface profiling, lateral scanning was adopted, and the measurement results were compared with the result of the Fourier method.
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http://dx.doi.org/10.1364/AO.408594DOI Listing
November 2020

High-speed combined NIR low-coherence interferometry for wafer metrology.

Appl Opt 2017 Nov;56(31):8592-8597

In this investigation, we describe a combined low-coherence interferometric technique to measure the surface and thickness profiles of wafers at once with high speed. The measurement system consists of a spectrally resolved interferometer to provide and monitor the optical path difference between two incident beams of the optical source part and a low-coherence scanning interferometer to measure the dimensions of wafers with significantly shortened scanning length. In the experiments, a silicon wafer and a sapphire wafer, of which both sides are polished, were used as targets of the measurement system for verification of the proposed system. As a result, the scanning length of the low-coherence scanning interferometer was reduced from a few millimeters to a few hundreds of micrometers approximately 10 times. In addition, surface profiles of both sides and thickness profiles were simultaneously measured to reconstruct 3D shapes of wafers.
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http://dx.doi.org/10.1364/AO.56.008592DOI Listing
November 2017

Dual low coherence scanning interferometry for rapid large step height and thickness measurements.

Opt Express 2016 Dec;24(25):28625-28632

In this investigation, we propose a dual low coherence scanning interferometer as the novel concept to measure large height steps on the topographic surface of a specimen and the thickness profile of a transparent optical plate. Dual low coherence characteristics by the tandem interferometric configuration can generate several discrete correlograms for the measured surfaces, which provide the possibility to reduce the scanning length of typical low coherence scanning interferometry significantly. Also, the spectrally-resolved interferometric method is combined to monitor the distance gaps between correlograms caused by the dual low coherence. To verify the proposed interferometry, a large height step specimen and a silicon wafer were used and the 3D surface and thickness profiles were rapidly and successfully measured. In addition, the technique which can identify each correlogram by the insertion of dispersive plates are suggested in this paper.
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http://dx.doi.org/10.1364/OE.24.028625DOI Listing
December 2016

Global and focused transcriptional profiling of small molecule aminopeptidase N inhibitor reveals its mechanism of angiogenesis inhibition.

Biochem Biophys Res Commun 2008 Jun 14;371(1):99-103. Epub 2008 Apr 14.

Chemical Genomics Laboratory, Department of Biotechnology, College of Life Science & Biotechnology, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul 120-749, Republic of Korea.

We recently developed a specific small molecule inhibitor of aminopeptidase N (APN), named as HNSA, through a high throughput screening. In the present study, we investigated the major cellular phenotypes of HNSA in comparison with those of APN knock-down in human fibrosarcoma cells and the mechanism of angiogenesis inhibition by the compound using DNA microarray analyses. Global gene expression analyses showed that HNSA signatures are significantly correlated with those of APN knock-down in HT1080 cells, suggesting that APN is a primary target of HNSA in the cells. Using the angiogenesis-focused DNA microarrays, nine of angiogenesis-related genes were identified as crucial mediators of angiogenesis inhibition by HNSA. These data demonstrate that HNSA can be used as a valuable tool to decipher the APN function in angiogenesis.
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http://dx.doi.org/10.1016/j.bbrc.2008.04.023DOI Listing
June 2008

Development of anangiogenesis-focused cDNA chip and validation of its functionality.

Exp Mol Med 2005 Aug;37(4):365-70

Chemical Genomics National Research Laboratory, Department of Bioscience and Biotechnology, Institute of Bioscience, Sejong University, 98 Kunja-dong, Kwangjin-gu, Seoul 143-747, Korea.

DNA chip has been used as a powerful tool to study the genetic reprogramming of cells and its link to cellular phenotype such as angiogenesis. To evaluate the angiogenesis related genetic reprogramming more efficiently, we here developed an angiogenesis-focused cDNA chip containing 153 angiogenesis related genes arrayed in duplicate on a slide glass. In order to validate the functionality of the angiogenesis-focused cDNA chip, we examined gene expression profiles in HT1080 cells treated with either fetal bovine serum, a well known pro-angiogenic factor, or trichostatin A, a known angiogenesis inhibitor, using the cDNA chip. All duplicate data from the analysis are well matched with each other and gene expression profiles are well consistent with previously reported data. These results demonstrate that the angiogenesis-focused cDNA chip developed here can be a useful tool towards angiogenesis- related researches.
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http://dx.doi.org/10.1038/emm.2005.46DOI Listing
August 2005