A5013411510- Digital Holography and Microscopy
- Spectroscopy Techniques in Biomedical and Chemical Research
- Optical Coherence Tomography Applications
- Photoacoustic and Ultrasonic Imaging
- Microfluidic and Bio-sensing Technologies
- Advanced Fluorescence Microscopy Techniques
- Thermography and Photoacoustic Techniques
- Cell Image Analysis Techniques
- Optical measurement and interference techniques
- Image Processing Techniques and Applications
- Spectroscopy and Chemometric Analyses
- Urban Heat Island Mitigation
- Advanced X-ray Imaging Techniques
- Random lasers and scattering media
- Parasitic Infections and Diagnostics
- 3D Printing in Biomedical Research
- Atmospheric aerosols and clouds
- Laser Material Processing Techniques
- Advanced Optical Imaging Technologies
- Infrared Thermography in Medicine
- Photorefractive and Nonlinear Optics
- Advanced Fiber Laser Technologies
- Eosinophilic Esophagitis
- Innovative Microfluidic and Catalytic Techniques Innovation
- Optical and Acousto-Optic Technologies
The University of Tokyo
2015-2024
University of California, Los Angeles
2017-2021
Graduate School USA
2021
Los Angeles City College
2020
California NanoSystems Institute
2018-2019
Abstract Quantitative phase imaging (QPI) with its high-contrast images of optical delay (OPD) maps is often used for label-free single-cell analysis. Contrary to other methods, sensitivity improvement has not been intensively explored because conventional QPI sensitive enough observe the surface roughness a substrate that restricts minimum measurable OPD. However, emerging techniques utilize, example, differential image analysis consecutive temporal frames, such as mid-infrared photothermal...
We report a deep learning-enabled field-portable and cost-effective imaging flow cytometer that automatically captures phase-contrast color images of the contents continuously flowing water sample at throughput 100 mL/h. The device is based on partially coherent lens-free holographic microscopy acquires diffraction patterns micro-objects inside microfluidic channel. These are reconstructed in real time using learning-based phase-recovery image-reconstruction method to produce image each...
Autofocusing is essential to digital holographic imaging. Previously used autofocusing criteria exhibit challenges when applied to, e.g., connected objects with different optical properties. Furthermore, in some of the earlier criteria, polarity, i.e., whether search for peak or valley as a function depth, changes types samples, which creates another challenge. Here, we propose robust and accurate criterion that based on edge sparsity complex wavefront, termed "sparsity gradient" (SoG). We...
Label-free optical imaging is valuable in biology and medicine because of its non-destructive nature. Quantitative phase (QPI) molecular vibrational (MVI) are the two most successful label-free methods, providing morphological biochemical information, respectively. These techniques have enabled numerous applications as they matured over past few decades; however, their contrasts inherently complementary difficult to integrate due reliance on different light–matter interactions. Here we...
Advancement in mid-infrared (MIR) technology has led to promising biomedical applications of MIR spectroscopy, such as liquid biopsy or breath diagnosis. On the contrary, microscopy been rarely used for live biological samples an aqueous environment due lack spatial resolution and large water absorption background. Recently, photothermal (MIP) imaging proven be applicable 2D 3D single-cell with high inherited from visible light. However, maximum measurement rate limited several frames s-1,...
Pulmonary fibrosis (PF), a condition characterized by inflammation and collagen deposition in the alveolar interstitium, causes dyspnea fatal outcomes. Although bleomycin-induced PF mouse model has improved our understanding of exogenous factor-induced fibrosis, mechanism governing endogenous remains unknown. Here, we find that Ifngr1
We propose and demonstrate a coherent Raman scattering (CRS) spectroscopy technique capable of acquiring 50,000 broadband spectra/s. This ultrafast spectral acquisition is realized by employing Fourier-domain delay line based on rapidly rotating polygonal mirror array as an optical path-length scanner in Fourier-transform anti-Stokes (FT-CARS) platform. provide theoretical description the proposed FT-CARS while also presenting its proof-of-concept demonstration liquid toluene sample. Our use...
Abstract An optical microscope enables image-based findings and diagnosis on microscopic targets, which is indispensable in many scientific, industrial medical settings. A standard benchtop platform, equipped with e.g., bright-field phase-contrast modes, of importance convenience for various users because the wide-field label-free properties allow morphological imaging without need specific sample preparation. However, these microscopes never have capability acquiring molecular contrast a...
Quantitative phase imaging (QPI) quantifies the sample-specific optical-phase-delay enabling objective studies of optically-transparent specimens such as biological samples, but lacks chemical sensitivity limiting its application to morphology-based diagnosis. We present wide-field molecular-vibrational microscopy realized in framework QPI utilizing mid-infrared photothermal effect. Our technique provides spectroscopic performance comparable that a conventional infrared spectrometer...
A recently developed ultrafast burst imaging method known as sequentially timed all-optical mapping photography (STAMP) [Nat. Photonics8, 695 (2014)10.1038/nphoton.2014.163] has been shown effective for studying a diverse range of complex phenomena. Its image separation circumvents mechanical and electronic restrictions that traditional methods have long struggled with, hence realizing ultrafast, continuous, burst-type recording at fame rate far beyond what is achievable with conventional...
We present sequentially timed all-optical mapping photography (STAMP) with a slicing mirror in branched 4f system for an increased number of frames without sacrificing pixel resolution. The spectrally separates the laser light path into multiple paths by placed Fourier plane. Fabricated ultra-precision end milling process, has 18 facets differing angles. used boosted STAMP to observe dynamics ablation two image sensors which captured subsequent at frame rate 126 billion per second,...
We report a field-portable and cost-effective imaging flow cytometer that uses deep learning to accurately detect Giardia lamblia cysts in water samples at volumetric throughput of 100 mL/h. This lensfree color holographic capture reconstruct phase intensity images microscopic objects continuously flowing sample, automatically identifies Lamblia real-time without the use any labels or fluorophores. The is housed an environmentally-sealed enclosure with dimensions 19 cm x 16 weighs 1.6 kg....
Label-free particle analysis is a powerful tool in chemical, pharmaceutical, and cosmetic industries as well basic sciences, but its throughput significantly lower than that of fluorescence-based counterparts. Here we present label-free single-particle analyzer based on broadband dual-comb coherent Raman scattering spectroscopy operating at spectroscopic scan rate 10 kHz. As proof-of-concept demonstration, perform anti-Stokes measurements polystyrene microparticles flowing an acoustofluidic...
3D cell cultures are indispensable in recapitulating vivo environments. Among the many culture methods, culturing adherent cells on hydrogel beads to form spheroid-like structures is a powerful strategy for maintaining high viability and functions states. However, high-throughput, scalable technologies imaging of individual cultured scaffolds lacking. This study reports development throughput, flow cytometry platform analyzing spheroid models. realized by integrating single objective...
The Sparsity of the Gradient (SoG) is a robust autofocusing criterion for holography, where gradient modulus complex refocused hologram calculated, on which sparsity metric applied. Here, we compare two different choices metrics used in SoG, specifically, Gini index (GI) and Tamura coefficient (TC), holographic dense/connected or sparse samples. We provide theoretical analysis predicting that uniformly distributed image data, TC GI exhibit similar behavior, while naturally images containing...
We propose and demonstrate an optical component that overcomes critical limitations in our previously demonstrated high-speed multispectral videography—a method which array of periscopes placed a prism-based spectral shaper is used to achieve snapshot imaging with the frame rate only limited by image-recording sensor. The consists slicing mirror incorporated into 4f-relaying lens system we refer as spectrum slicer (SS). With its simple design, can easily increase number channels without...
The Sparsity of the Gradient (SoG) is a robust autofocusing criterion for holography, where gradient modulus complex refocused hologram calculated, on which sparsity metric applied. Here, we compare two different choices metrics used in SoG, specifically, Gini index (GI) and Tamura coefficient (TC), holographic dense/connected or sparse samples. We provide theoretical analysis predicting that uniformly distributed image data, TC GI exhibit similar behavior, while naturally images containing...
Abstract Three-dimensional (3D) cell cultures are indispensable in recapitulating vivo environments. Among many 3D culture methods, the strategy to adherent cells on hydrogel beads form spheroid-like structures is powerful for maintaining high viability and functions through an efficient supply of nutrients oxygen. However, high-throughput, scalable technologies imaging individual cultured scaffolds lacking. This study reports development a flow cytometry (3D-iFCM) platform analyzing...
A robust holographic autofocusing criterion based on the edge sparsity of refocused images is presented. Its performance experimentally validated by imaging various samples with different complex valued optical transmission functions.
Forest fires are a major source of particulate matter (PM) air pollution on global scale. The composition and impact PM typically studied using only laboratory instruments extrapolated to real fire events owing lack analytical techniques suitable for field-settings. To address this similar field test challenges, we developed mobilemicroscopy- machine-learning-based quality monitoring platform called c-Air, which can perform sampling microscopic analysis aerosols in an integrated portable...
Acquisition of molecular information is useful in various aspects science, industry and medicine. Fluorescence imaging the most widely used technique biological fields, but accompanied by chemical alteration photodamage to sample due use fluorescent labelling agents. Alternatively, label-free molecular-vibrational methods, such as mid-infrared (MIR) absorption spontaneous/coherent Raman scattering (RS) [1], suffer from low spatial resolution, sensitivity (low speed), high and/or need...
Label-free optical imaging is valuable in biology and medicine with its non-destructive property reduced chemical damages. Quantitative phase (QPI) molecular vibrational (MVI) are the two most successful label-free methods, providing morphology biochemistry, respectively, that have pioneered numerous applications along their independent technological maturity over past few decades. However, distinct contrasts inherently complementary difficult to integrate due use of different light-matter...
Advancement in mid-infrared (MIR) technology has led to promising biomedical applications of MIR spectroscopy, such as liquid biopsy or breath diagnosis. On the contrary, microscopy been rarely used for live biological samples an aqueous environment due lack spatial resolution and large water absorption background. Recently, photothermal (MIP) imaging proven be applicable 2D 3D single-cell with high inherited from visible light. However, maximum measurement rate limited several frames/s,...