Iyll-Joon Doh

Experience

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  Samsung Electronics

  Jun 2013 - Aug 2013

  Intern

  Mechanical Engineering Intern, Instrumentation Group, X-Ray Equipment Development Part • Gained comprehensive knowledge in the mechanical development of components in digital X-ray equipment, including an understanding of injection molding and die-casting processes.• Enhanced the mechanical designs of the motor components in X-ray Bucky stands utilizing Siemens NX software. • Delivered a product durability test on the X-ray receptor handle for quality assurance.

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  Purdue University

  Jan 2014 - Aug 2022

  Graduate Research Assistant

  Applied Optics Laboratory• Participated in interdisciplinary research projects funded by USDA-ARS, developing foodborne pathogen detection techniques using optical methods.• Designed and validated a phenotyping method for bacterial colonies using hyperspectral elastic light-scatter patterns, employing a supercontinuum (SC) laser and an acousto-optic tunable filter (AOTF) to generate hyperspectral pattern images for analyzing optical and morphological characteristics of bacterial colonies.• Engineered a multimodal microscopy instrument integrating bright-field, confocal, and diffractive imaging techniques for an in-depth analysis of the optical and morphological properties of foodborne pathogens. • Performed image processing on microscope and diffraction pattern images using ImageJ and MATLAB, optimizing pattern contrast for efficient feature extraction, and subsequently employed a variety of mathematical models to extract features such as Zernike moments and Haralick textures.• Conducted optical simulations using a mathematical model in MATLAB, derived from scalar diffraction theory, to predict elastic diffraction patterns based on bacterial colony morphology and the wavelength of the incident laser beam. • Built smartphone-based optical measuring devices for bioluminescence and fluorescence detection that deliver rapid and on-site detection of foodborne pathogens.• Developed a portable spark-induced breakdown spectroscopy instrument for precise heavy metal detection, integrating a handheld spectrometer and a custom-built delay generator to accurately measure levels of gadolinium, aluminum, and copper.• Designed and validated a reflected scatterometry for non-invasive interrogation of bacterial colonies.• Engineered a non-invasive glucose sensing unit, leveraging a photodiode array to measure the spatial intensity of elastic light scattering in tissue phantoms, combined with shifted-excitation Raman difference spectroscopy (SERDS). Show less

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  Purdue University Mechanical Engineering

  Aug 2021 - May 2022

  Graduate Teaching Assistant

  • Taught lab sections for the ME365 course (Measurement and Control Systems I), providing third-year Mechanical Engineering students with hands-on experience in signal control, measurement, and processing.

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  Purdue University Cytometry Laboratories

  Sept 2022 - Jul 2023

  Postdoctoral Research Associate

  • Integrated laser-induced breakdown spectroscopy, Raman spectroscopy, and fluorescence techniques for pathogen detection.• Applied machine learning and image processing techniques to classify bacterial colonies from hyperspectral light scattering patterns.

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  MetroLaser, Inc.

  Aug 2023 - now

  Optical Engineer

  Research and Development of Digital Holographic Microscope• Led the product development of a lensless digital holographic microscope, contributing to hardware and software development, building and testing prototypes, and conducting market testing for product validation. • Designed and implemented a C++ application for real-time hologram capture and reconstruction, integrating a phase retrieval algorithm to generate phase and intensity images.• Contributed to the development of a dual-mode digital holographic fluorescence imaging system by optimizing optical layout and designing opto-mechanical structures and housing using ray-tracing and 3D modeling. Show less