• Journal of Photoscience
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• 제11권2호
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• pp.47-53
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• 2004

A laser scanning fluorescence microscope system has been fabricated for single molecule detection (SMD). Problems associated with the system set-up have been discussed along with proper suggestions. Based on the SMD results obtained by using the apparatus, a statistical method has been suggested to determine the minimum number of required molecules to form a group of uniform average in a selected error range.

• Current Optics and Photonics
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• 제8권4호
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• pp.327-344
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• 2024

Optical phantoms are essential in optical imaging and measurement instruments for performance evaluation, calibration, and quality control. They enable precise measurement of image resolution, accuracy, sensitivity, and contrast, which are crucial for both research and clinical diagnostics. This paper reviews the recent advancements and challenges in phantoms for optical coherence tomography, photoacoustic imaging, digital holographic microscopy, optical diffraction tomography, and oximetry tools. We explore the fundamental principles of each technology, the key factors in phantom development, and the evaluation criteria. Additionally, we discuss the application of phantoms used for enhancing optical-image quality. This investigation includes the development of realistic biological and clinical tissue-mimicking phantoms, emphasizing their role in improving the accuracy and reliability of optical imaging and measurement instruments in biomedical and clinical research.

• 한국광학회지
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• 제18권1호
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• pp.44-49
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• 2007

광섬유 망을 통해 수 kHz의 좁은 선폭을 가지는 $1.5{\mu}m$ 레이저광원을 높은 전송 안정도로 전송하였다. 525 m 길이의 단일모드 광섬유를 통과하면서 발생하는 광 위상 잡음을 능동적으로 제거하는 실험 장치를 구성하였고, 이렇게 하여 전송된 광 주파수의 전송 안정도는 1 초의 평균시간에서 $2{\times}10^{-17}$로 측정되었다. 전송된 광 주파수의 품질을 주파수 영역과 시간 영역에서 정량적으로 분석하였다.

• 한국정밀공학회지
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• 제19권1호
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• pp.25-32
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• 2002

• 한국광학회:학술대회논문집
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• 한국광학회 2008년도 동계학술발표회 논문집
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• pp.257-258
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• 2008

• 한국광학회:학술대회논문집
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• 한국광학회 2007년도 하계학술발표회 논문집
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• pp.193-194
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• 2007

• 한국광학회:학술대회논문집
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• 한국광학회 2007년도 동계학술발표회 논문집
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• pp.149-150
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• 2007

• Current Optics and Photonics
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• 제3권1호
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• pp.33-39
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• 2019

We report development of a frequency-stabilized mid-infrared continuous-wave (cw) optical parametric oscillator (OPO) based on a fan-out grating MgO:PPLN crystal pumped at 1064 nm. The OPO resonator was designed as a pump-enhanced standing-wave cavity that resonates to the pump and signal beams. To realize stable operation of the OPO, we applied a modified Pound-Drever-Hall technique, which is a well-known method for powerful laser frequency stabilization. Tuning a poling period of the fan-out grating of the crystal allows wavelength-tunable OPO outputs from 1510 nm to 1852 nm and from 2500 nm to 3600 nm for signal and idler beams, respectively. At the idler wavelengths of 2500 nm, 3000 nm and 3500 nm, we achieved more than 50 mW of output powers at a pumping power of 1.1 W. The long-term stability of the OPO was confirmed by recording the power and wavelength variations of the idler for an hour.

• Journal of the Optical Society of Korea
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• 제20권6호
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• pp.733-738
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• 2016

We calculate optical properties of guided modes of a hybrid-guiding photonic crystal fiber. The design and modeling of such hybrid-guiding PCF is made by replacing air holes with inserts of high refractive index material layer by layer in order. The optical properties such as mode intensity profile, mode dispersion, optical birefringence, confinement loss, and chromatic dispersion during transition of the guiding mechanism are analyzed and discussed. The guided modes in the hybrid-guiding region are also compared with those of reference index-guiding and bandgap-guiding photonic crystal fibers.

• Journal of the Optical Society of Korea
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• 제7권3호
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• pp.150-155
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• 2003

Femtosecond laser ablation mechanism was systematically investigated on sodalime glass in ambient conditions. The ablation crater diameter was measured for varying numbers of laser pulses as for varying well as the laser fluence. The analysis of the results with a one dimensional spatial Gaussian fluence distribution reveals that the inherent ablation mechanism has been altered from a multi-photon process to a single photon excitation due to defect sites that have been accumulated by successive laser pulses. Furthermore, the transition between the two regimes was found to be a function of both the laser fluence and the number of laser shots.