Dr. Dong-hak Choi Profile

Dr. Dong-hak Choi

at Kitasato Univ

SPIE Involvement:

Author

Publications (21)

Proceedings Article | 27 February 2020 Paper

Morphological diversity of lacrimal canaliculus observed by dynamic OCT with extrinsic contrast agent

Reiko Yoshimura, Dong-Hak Choi, Masahiro Fujimoto, Akihito Uji, Fumiko Hiwatashi, Kohji Ohbayashi

Proceedings Volume 11218, 112181T (2020) https://doi.org/10.1117/12.2545365

KEYWORDS: Optical coherence tomography, Image segmentation, 3D image reconstruction, 3D image processing

Read Abstract +

Proceedings Article | 28 February 2019 Paper

Lacrimal canaliculus imaging by dynamic OCT using extrinsic contrast agent

Reiko Yoshimura, Dong-hak Choi, Masahiro Fujimoto, Akihito Uji, Fumiko Hiwatashi, Kohji Ohbayashi

Proceedings Volume 10858, 108581H (2019) https://doi.org/10.1117/12.2508137

KEYWORDS: Optical coherence tomography, Image segmentation, Eye, 3D image processing

Read Abstract +

Proceedings Article | 17 February 2017 Paper

Speckle variance optical coherence tomography using an SS-OCT system and an extended k-sampling clock

Reiko Yoshimura, Dong-Hak Choi, Kohji Ohbayashi

Proceedings Volume 10053, 100532P (2017) https://doi.org/10.1117/12.2250717

KEYWORDS: Optical coherence tomography, Coherence (optics), Light sources, Biomedical optics, Point spread functions, Tissues, Imaging systems, Speckle, Reflectors, Refractive index, Signal generators, Laser resonators

Read Abstract +

Proceedings Article | 20 March 2013 Paper

Enhancement of the depth range up to 13.8 mm with filtered external k-sampling-clock in an SS-OCT system using a reflective Fabry-Perot tunable laser

Hisashi Yamada, Yasuo Niimura, Fumiko Hiwatashi, Dong-Hac Choi, Kohji Ohbayashi

Proceedings Volume 8571, 85710C (2013) https://doi.org/10.1117/12.2002226

KEYWORDS: Optical coherence tomography, Optical filters, Clocks, Point spread functions, Tunable lasers, Signal detection, Fabry–Perot interferometers, Image segmentation, Reflectivity, Linear filtering

Read Abstract +

Proceedings Article | 14 February 2012 Paper

Image diversity, shape modification with accommodation, dynamical change with accommodation, and age dependence of the ciliary body imaged by optical coherence tomography

Kimiya Shimizu, Nobuyuki Satou, Akihito Igarashi, Motoi Nakanishi, Atsushi Goto, Donghak Choi, Reiko Yoshimura, Hideaki Hiro-Oka, Hiroyuki Furukawa, Kohji Ohbayashi

Proceedings Volume 8209, 820909 (2012) https://doi.org/10.1117/12.905401

KEYWORDS: Optical coherence tomography, Eye, Image segmentation, Iris, 3D image processing, Video, Sclera, Ultrafast phenomena, Imaging systems, Refraction

Read Abstract +

Proceedings Article | 30 January 2012 Paper

Optical amplification of the signal and sensitivity of the ultrafast spectral domain optical coherence tomography at an A-scan rate of 10MHz in a wavelength region of 1300nm

D. Choi, H. Hiro-oka, K. Shimizu, K. Ohbayashi

Proceedings Volume 8213, 82131F (2012) https://doi.org/10.1117/12.906536

KEYWORDS: Optical coherence tomography, Point spread functions, Field programmable gate arrays, Data processing, Skin, 3D image processing, Data acquisition, Biomedical optics, Ultrafast phenomena, Semiconductor optical amplifiers

Read Abstract +

Proceedings Article | 30 January 2012 Paper

Discretely swept optical coherence tomography system using super-structure grating distributed Bragg reflector lasers at 1561-1639nm

D. Choi, R. Yoshimura, H. Hiro-Oka, H. Furukawa, A. Goto, N. Satoh, A. Igarashi, M. Nakanishi, K. Shimizu, K. Ohbayashi

Proceedings Volume 8213, 82132F (2012) https://doi.org/10.1117/12.905413

KEYWORDS: Optical coherence tomography, Point spread functions, Interference (communication), Tissue optics, Distributed Bragg reflectors, Frequency combs, Laser systems engineering, Image segmentation, Biomedical optics, Laser optics

Read Abstract +

Proceedings Article | 30 January 2012 Paper

Detailed software design of an ultra-parallel ultra-high speed SD-OCT for real-time 4D display at 12 volume/second

H. Hiro-Oka, D. Choi, K. Shimizu, K. Ohbayashi

Proceedings Volume 8213, 821339 (2012) https://doi.org/10.1117/12.906948

KEYWORDS: Optical coherence tomography, Field programmable gate arrays, Data acquisition, Data processing, 3D image processing, 3D displays, Demultiplexers, Interfaces, Graphics processing units, 3D acquisition

Read Abstract +

Proceedings Article | 12 February 2011 Paper

Ultra-high speed real-time 4D display system installed in ultra-high-speed parallel OCT system at a volume rate of 12 volumes/sec

K. Ohbayashi, D. Choi, H. Hiro-oka, A. Kubota, T. Ohno, R. Ikeda, K. Shimizu

Proceedings Volume 7889, 78891Z (2011) https://doi.org/10.1117/12.874576

KEYWORDS: Optical coherence tomography, Data acquisition, 3D displays, 3D image processing, Video, Tissues, Biopsy, Data processing, Diagnostics, Field programmable gate arrays

Read Abstract +

Proceedings Article | 12 February 2011 Paper

Full-range imaging of the whole anterior segment of eye by high-speed optical frequency domain imaging using a reflective Fabry-Perot tunable laser

Hiroyuki Furukawa, Hideaki Hiro-Oka, Reiko Yoshimura, Dong-Hak Choi, Motoi Nakanishi, Akihito Igarashi, Kohji Ohbayashi, Kimiya Shimizu

Proceedings Volume 7885, 78850V (2011) https://doi.org/10.1117/12.874077

KEYWORDS: Image segmentation, Eye, Optical imaging, Cornea, Crystals, Imaging systems, Reflectivity, Fabry–Perot interferometers, Tunable lasers, Iris

Read Abstract +

Proceedings Article | 18 February 2009 Paper

24 mm depth range discretely swept optical frequency domain imaging in dentistry

Hideo Kakuma, DongHak Choi, Hiroyuki Furukawa, Hideaki Hiro-Oka, Kohji Ohbayashi

Proceedings Volume 7162, 716208 (2009) https://doi.org/10.1117/12.807235

KEYWORDS: Optical coherence tomography, Point spread functions, Laser dentistry, Reflectors, Imaging systems, Optical imaging, Teeth, Light sources, Dentistry, Reflectometry

Read Abstract +

Proceedings Article | 5 March 2008 Paper

Doppler optical coherence tomography measurements in discretely swept optical frequency domain imaging

Reiko Yoshimura, Hideaki Hiro-Oka, DongHak Choi, Hiroyuki Furukawa, Naoki Fujiwara, Kohji Ohbayashi

Proceedings Volume 6847, 68472G (2008) https://doi.org/10.1117/12.764331

KEYWORDS: Optical coherence tomography, Doppler tomography, Light sources, Imaging systems, Optical imaging, Doppler effect, Optical testing, Biomedical optics, Photonics, Phase shifts

Read Abstract +

Proceedings Article | 18 February 2008 Paper

60 MHz A-line rate ultra-high speed Fourier-domain optical coherence tomography

K. Ohbayashi, D. Choi, H. Hiro-Oka, H. Furukawa, R. Yoshimura, M. Nakanishi, K. Shimizu

Proceedings Volume 6847, 68470M (2008) https://doi.org/10.1117/12.764133

KEYWORDS: Optical coherence tomography, Data acquisition, Demultiplexers, Scanners, 3D image processing, Mirrors, Point spread functions, Terahertz radiation, Imaging systems, Electronics

Read Abstract +

Proceedings Article | 18 February 2008 Paper

Use of cosine tapered window to improve dynamic range of OCT without loss of resolution

Hideaki Hiro-Oka, DongHak Choi, Hiroyuki Furukawa, Reiko Yoshimura, Kohji Ohbayashi, Takeyuki Wakabayashi

Proceedings Volume 6847, 68472C (2008) https://doi.org/10.1117/12.761459

KEYWORDS: Optical coherence tomography, Tunable lasers, Light sources, Mirrors, Fourier transforms, L band, Skin, Optical imaging, Laser development, Signal detection

Read Abstract +

Proceedings Article | 18 February 2008 Paper

Penetration depth of optical frequency domain imaging at wavelengths of 1310 nm and 1550 nm

Hiroyuki Furukawa, DongHak Choi, Hideaki Hiro-Oka, Reiko Yoshimura, Motoi Nakanishi, Kimiya Shimizu, Kohji Ohbayashi

Proceedings Volume 6847, 68472V (2008) https://doi.org/10.1117/12.766846

KEYWORDS: Tissue optics, Biomedical optics, Hard tissue optics, Optical imaging, Optical coherence tomography, Coherence (optics), Laser scanners, 3D scanning, Receivers, Mirrors

Read Abstract +

Proceedings Article | 7 February 2007 Paper

High-speed optical-frequency domain imaging by one frame imaging within one single frequency sweep

Hiroyuki Furukawa, Takuji Amano, DongHak Choi, Hideaki Hiro-Oka, Kohji Ohbayashi

Proceedings Volume 6429, 64292D (2007) https://doi.org/10.1117/12.704565

KEYWORDS: Optical coherence tomography, Data acquisition, Mirrors, Scanners, Tomography, Data transmission, Optical scanning, In vivo imaging, Biomedical optics, Light sources

Read Abstract +

Proceedings Article | 7 February 2007 Paper

A method of improving scanning speed and resolution of OFDR-OCT using multiple SSG-DBR lasers simultaneously

DongHak Choi, Hideaki Hiro-Oka, Takuji Amano, Hiroyuki Furukawa, Naoki Fujiwara, Hiroyuki Ishii, Kohji Ohbayashi

Proceedings Volume 6429, 64292E (2007) https://doi.org/10.1117/12.704250

KEYWORDS: Optical coherence tomography, Mirrors, Reflectivity, Interferometers, Solids, Pellicles, L band, Data acquisition, Time metrology, Switching

Read Abstract +

Proceedings Article | 7 February 2007 Paper

Discretely swept optical-frequency domain imaging toward high-resolution, high-speed, high-sensitivity, and long-depth-range

K. Ohbayashi, T. Amano, H. Hiro-oka, H. Furukawa, D. Choi, P. Jayavel, R. Yoshimura, K. Asaka, N. Fujiwara, H. Ishii, M. Suzuki, M. Nakanishi, K. Shimizu

Proceedings Volume 6429, 64291G (2007) https://doi.org/10.1117/12.703963

KEYWORDS: Optical coherence tomography, Laser development, Image enhancement, In vivo imaging, Semiconductor optical amplifiers, Telecommunications, Prototyping, Switching, Imaging systems, Optical amplifiers

Read Abstract +

Proceedings Article | 20 February 2006 Paper

Reconstruction of three-dimensional structure of an extracted tooth by OFDR-OCT

Hiroyuki Furukawa, Hideaki Hiro-Oka, Takuji Amano, DongHak Choi, Takeo Miyazawa, Ryoko Yoshimura, Kimiya Shimizu, Kohji Ohbayashi

Proceedings Volume 6079, 60790T (2006) https://doi.org/10.1117/12.648802

KEYWORDS: Optical coherence tomography, Teeth, 3D image processing, Refraction, Mirrors, 3D image reconstruction, Cornea, Ray tracing, Eye, Photonics

Read Abstract +

Proceedings Article | 13 April 2005 Paper

Tissue imaging by OFDR-OCT using an SSG-DBR laser

DongHak Choi, Takuji Amano, Hideaki Hiro-Oka, Hiroyuki Furukawa, Takeo Miyazawa, Ryoko Yoshimura, Motoi Nakanishi, Kimiya Shimizu, Kohji Ohbayashi

Proceedings Volume 5690, (2005) https://doi.org/10.1117/12.592544

KEYWORDS: Optical coherence tomography, Signal attenuation, Tissues, Skin, Image segmentation, Blood, Light sources, Teeth, Tissue optics, Laser development

Read Abstract +

Proceedings Article | 2 August 2004 Paper

OFDR with an SSG-DBR laser

Takuji Amano, Hideaki Hiro-Oka, DongHak Choi, Hiroyuki Furukawa, Fumiyoshi Kano, Mitsuo Takeda, Motoi Nakanishi, Kimiya Shimizu, Kohji Obayashi

Proceedings Volume 5531, (2004) https://doi.org/10.1117/12.559120

KEYWORDS: Optical coherence tomography, Teeth, Light sources, Laser dentistry, Refractive index, Mirrors, Interferometry, Bismuth, Telecommunications, Laser development

Read Abstract +

Showing 5 of 21 publications

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Keywords/Phrases

Search In:

Publication Years