Complete amplitude and phase control of light using broadband holographic metasurfaces

Lee, Gun-Yeal,Yoon, Gwanho,Lee, Seung-Yeol,Yun, Hansik,Cho, Jaebum,Lee, Kyookeun,Kim, Hwi,Rho, Junsuk,Lee, Byoungho The Royal Society of Chemistry 2018 Nanoscale Vol.10 No.9

<P>Reconstruction of light profiles with amplitude and phase information, called holography, is an attractive optical technology with various significant applications such as three-dimensional imaging and optical data storage. Subwavelength spatial control of both amplitude and phase of light is an essential requirement for an ideal hologram. However, traditional holographic devices suffer from their restricted capabilities of incomplete modulation in both amplitude and phase of visible light; this results in sacrifice of optical information and undesirable occurrences of critical noises in holographic images. Herein, we have proposed a novel metasurface that is capable of completely controlling both the amplitude and phase profiles of visible light independently with subwavelength spatial resolution. The full, continuous, and broadband control of both amplitude and phase was achieved using X-shaped meta-atoms based on the expanded concept of the Pancharatnam-Berry phase. The first experimental demonstrations of the complete complex-amplitude holograms with subwavelength definition at visible wavelengths were achieved, and excellent performances with a remarkable signal-to-noise ratio as compared to those of traditional phase-only holograms were obtained. Extraordinary control capability with versatile advantages of our metasurface paves a way to an ideal holography, which is expected to be a significant advancement in the field of optical holography and metasurfaces.</P>

Additive light field displays : realization of augmented reality with holographic optical elements

Lee, Seungjae,Jang, Changwon,Moon, Seokil,Cho, Jaebum,Lee, Byoungho Association for Computing Machinery 2016 ACM transactions on graphics Vol.35 No.4

<P>We propose a see-through additive light field display as a novel type of compressive light field display. We utilize holographic optical elements (HOEs) as transparent additive layers. The HOE layers are almost free from diffraction unlike spatial light modulator layers, which makes this additive light field display more advantageous when modifying the number of layers, thickness, and pixel density compared with conventional compressive displays. Meanwhile, the additive light field display maintains advantages of compressive light field displays. The proposed additive light field display shows bright and full-color volumetric images in high definition. In addition, users can view real-world scenes beyond the displays. Hence, we expect that our method can contribute to the realization of augmented reality. Here, we describe implementation of a prototype additive light field display with two additive layers, evaluate the performance of transparent HOE layers, describe several results of display experiments, discuss the diffraction effect of spatial light modulators, and analyze the ability of the additive light field display to express uncorrelated light fields.</P>

mySyntenyPortal: an application package to construct websites for synteny block analysis

Lee, Jongin,Lee, Daehwan,Sim, Mikang,Kwon, Daehong,Kim, Juyeon,Ko, Younhee,Kim, Jaebum BioMed Central 2018 BMC bioinformatics Vol.19 No.-

<P><B>Background</B></P><P>Advances in sequencing technologies have facilitated large-scale comparative genomics based on whole genome sequencing. Constructing and investigating conserved genomic regions among multiple species (called synteny blocks) are essential in the comparative genomics. However, they require significant amounts of computational resources and time in addition to bioinformatics skills. Many web interfaces have been developed to make such tasks easier. However, these web interfaces cannot be customized for users who want to use their own set of genome sequences or definition of synteny blocks.</P><P><B>Results</B></P><P>To resolve this limitation, we present mySyntenyPortal, a stand-alone application package to construct websites for synteny block analyses by using users’ own genome data. mySyntenyPortal provides both command line and web-based interfaces to build and manage websites for large-scale comparative genomic analyses. The websites can be also easily published and accessed by other users. To demonstrate the usability of mySyntenyPortal, we present an example study for building websites to compare genomes of three mammalian species (human, mouse, and cow) and show how they can be easily utilized to identify potential genes affected by genome rearrangements.</P><P><B>Conclusions</B></P><P>mySyntenyPortal will contribute for extended comparative genomic analyses based on large-scale whole genome sequences by providing unique functionality to support the easy creation of interactive websites for synteny block analyses from user’s own genome data.</P>

Synteny Portal: a web-based application portal for synteny block analysis

Lee, Jongin,Hong, Woon-young,Cho, Minah,Sim, Mikang,Lee, Daehwan,Ko, Younhee,Kim, Jaebum Oxford University Press 2016 Nucleic acids research Vol.44 No.w1

<P>Recent advances in next-generation sequencing technologies and genome assembly algorithms have enabled the accumulation of a huge volume of genome sequences from various species. This has provided new opportunities for large-scale comparative genomics studies. Identifying and utilizing synteny blocks, which are genomic regions conserved among multiple species, is key to understanding genomic architecture and the evolutionary history of genomes. However, the construction and visualization of such synteny blocks from multiple species are very challenging, especially for biologists with a lack of computational skills. Here, we present Synteny Portal, a versatile web-based application portal for constructing, visualizing and browsing synteny blocks. With Synteny Portal, users can easily (i) construct synteny blocks among multiple species by using prebuilt alignments in the UCSC genome browser database, (ii) visualize and download syntenic relationships as high-quality images, (iii) browse synteny blocks with genetic information and (iv) download the details of synteny blocks to be used as input for downstream synteny-based analyses, all in an intuitive and easy-to-use web-based interface. We believe that Synteny Portal will serve as a highly valuable tool that will enable biologists to easily perform comparative genomics studies by compensating limitations of existing tools. Synteny Portal is freely available at http://bioinfo.konkuk.ac.kr/synteny_portal.</P>

Viewing angle enhancement of an integral imaging display using Bragg mismatched reconstruction of holographic optical elements

Lee, Seungjae,Jang, Changwon,Cho, Jaebum,Yeom, Jiwoon,Jeong, Jinsoo,Lee, Byoungho The Optical Society 2016 Applied optics Vol.55 No.3

<P>Holographic-optical-element (HOE)-based integral imaging display can be applied to augmented reality. However, a narrow viewing angle is a bottleneck for commercialization. Here, we propose a method to enhance the viewing angle of the integral imaging display using Bragg mismatched reconstruction of HOEs. The viewing angle of the integral imaging display can be enlarged with two probe waves, which form two different viewing zones. The effect of Bragg mismatched reconstruction is analyzed with simulation and experiment. In order to show feasibility of the proposed method, a display experiment is demonstrated. (C) 2015 Optical Society of America</P>

Analysis and Implementation of Hologram Lenses for See-Through Head-Mounted Display

Lee, Seungjae,Lee, Byounghyo,Cho, Jaebum,Jang, Changwon,Kim, Jonghyun,Lee, Byoungho IEEE 2017 IEEE photonics technology letters Vol.29 No.1

<P>We introduce an approach to implementation of see-through head-mounted displays using hologram lenses, which are categorized by holographic optical elements. The hologram lenses magnify displayed images and superimpose the magnified images on the real-world simultaneously, which allows system configuration to be compact. Here, we investigate imaging properties and optical issues of hologram lenses using the spectral analysis of light field. Also, the astigmatism of hologram lenses is analyzed and its compensation method is proposed and verified. We conclude by describing display results and a practical application of the proposed method.</P>

Immobilization of aminophenylboronic acid on magnetic beads for the direct determination of glycoproteins by matrix assisted laser desorption ionization mass spectrometry

Lee, Jeong Heon,Kim, Yangsun,Ha, Mi Young,Lee, Eun Kyu,Choo, Jaebum Springer-Verlag 2005 Journal of the American Society for Mass Spectrome Vol.16 No.9

<P>Aminophenylboronic acid (APBA) has been immobilized on magnetic beads for the direct determination of glycoprotein by matrix assisted laser desorption/ionizaton time of flight mass spectrometry (MALDI-TOF-MS). An APBA layer was formed on the surface of carboxylic acid terminated magnetic beads by coupling with carbodiimide and subsequently reacted with an N-hydroxysuccinimide moiety. The immobilized APBA was identified by MALDI-TOF-MS without a matrix. Glycoproteins, such as HbA1c, fibrinogen, or RNase B were separated and desalted using APBA magnetic beads by simply washing the magnetic beads and then separating them by external magnet. Proteins can be identified by direct determination of proteins on beads on MALDI plate and confirmed again by peptide mass finger printing after digestion of proteins on magnetic beads by trypsin. Fluorescence image with a FITC tagging protein using confocal laser microscopy showed the difference of immobilization efficiency between glycoproteins and nonglycoproteins. The methods developed within this work allow the simple treatment and enrichment of glycoproteins as well as direct determination of proteins on beads by MALDI-TOF-MS.</P>

Quantitative Serodiagnosis of Scrub Typhus Using Surface-Enhanced Raman Scattering-Based Lateral Flow Assay Platforms

Lee, See Hi,Hwang, Joonki,Kim, Kihyun,Jeon, Jinhyeok,Lee, Sangyeop,Ko, Juhui,Lee, Jichul,Kang, Minhee,Chung, Doo Ryeon,Choo, Jaebum American Chemical Society 2019 ANALYTICAL CHEMISTRY - Vol.91 No.19

<P>A surface-enhanced Raman scattering-based lateral flow assay (SERS-LFA) technique has been developed for the rapid and accurate diagnosis of scrub typhus. Lateral flow kits for the detection of <I>O. tsutsugamushi</I> IgG (scrub typhus biomarker) were fabricated, and the calibration curve for various standard clinical sera concentrations were obtained by Raman measurements. The clinical sera titer values were determined by fitting the Raman data to the calibration curve. To assess the clinical feasibility of the proposed method, SERS-LFA assays were performed on 40 clinical samples. The results showed good agreement with those of the standard indirect immunofluorescence assay (IFA) method. SERS-LFA has many advantages over IFA including the less sample volume, simpler assay steps, shorter assay time, more systematic quantitative analysis, and longer assay lifetime. As SERS strips can be easily integrated with a miniaturized Raman spectrophotometer, field serodiagnosis is also more feasible.</P> [FIG OMISSION]</BR>

Fabrication of SERS-fluorescence dual modal nanoprobes and application to multiplex cancer cell imaging

Lee, Sangyeop,Chon, Hyangah,Yoon, Soo-Young,Lee, Eun Kyu,Chang, Soo-Ik,Lim, Dong Woo,Choo, Jaebum The Royal Society of Chemistry 2012 Nanoscale Vol.4 No.1

<P>We report a highly sensitive optical imaging technology using surface-enhanced Raman scattering (SERS)-fluorescence dual modal nanoprobes (DMNPs). Fluorescence microscopy is a well-known imaging technique that shows specific protein distributions within cells. However, most currently available fluorescent organic dyes have relatively weak emission intensities and are rapidly photo-bleached. Thus more sensitive and stable probes are needed. In this work we develop DMNPs, which can be used for both SERS and fluorescence detection. SERS detection is a powerful technique that allows ultrasensitive chemical or biochemical analysis through unlimited multiplexing and single molecule sensitivity. Combining advantages of fluorescence and SERS allows these dual modal nanostructures to be used as powerful probes for novel biomedical imaging. In this work, the fabrication and characterization of the SERS-fluorescence DMNPs and application to biological imaging were investigated using markers CD24 and CD44, which are co-expressed in MDA-MB-231 breast cancer cells, as a model system. SERS imaging with DMNPs was found to be a powerful tool to determine the co-localization of CD24 and CD44 in the cell.</P>

Advancement to International Market of Korean Firms in Super Long Span Bridge Projects Considering Key Stakeholders

Lee, Jung Ki,Lee, Jaebum,Lee, Kang-Wook,Han, Seung Heon,Yang Hae Bum 대한토목학회 2013 대한토목학회 학술대회 Vol.2013 No.10