We developed a compact and high-power modelocked fiber laser for multilayered optical memories. The average power and pulse width of the output pulse from the fiber laser that we developed were 109 mW and 2.1 ps, respectively. The dispersion of the output pulse was compensated with an external single-mode fiber of 2.5 m length. The pulse was compressed from 2.1 ps to 93 fs by dispersion compens...

Vol. 26 No. 5, 2014 659 Received April 3, 2013, Revised September 9, 2013, Accepted for publication October 13, 2013 Corresponding author: Sung-Yul Lee, Department of Dermatology, Soon Chun Hyang University Hospital Cheonan, 31 Suncheonhyang 6-gil, Dongnam-gu, Cheonan 330-721, Korea. Tel: 82-41-570-2270, Fax: 82-41-570-2783, E-mail: [email protected] This is an Open Access article distribute...

We developed SPECT imaging capability on an animal PET scanner to provide a cost effective option for animal SPECT imaging. The SPECT add-on sub-system was enabled by mechanically integrating a multiple-pinhole collimator in the PET detector ring. This study introduces a method to calibrate the geometrical parameters of the SPECT add-on using the PET imaging capability of the scanner. The propo...

We characterize and compare the axial and lateral performance of fluorescence confocal systems imaging in turbid media. The aperture configurations studied are a single pinhole, a slit, a Nipkow disk, and a linear array of pinholes. Systems with parallelized apertures are used clinically because they enable high-speed and real-time imaging. Understanding how they perform in highly scattering ti...

Nuclear angiocardiography with a gamma camera, a pinhole collimator, and 99mTc pertechnetate was performed on 43 children aged 3 years or less, including 10 neonates. Twenty-six children had congenital heart disease, which was confirmed at cardiac catheterization; the rest had no structural cardiac anomaly. Use of the pinhole collimator allowed magnification of cardiac images, with enhancement ...

Most algorithms in 3-D Computer Vision rely on the pinhole camera model because of its simplicity, whereas video optics, especially low-cost wide-angle or fish-eye lens, generate a lot of non-linear distortion which can be critical. To find the distortion parameters of a camera, we use the following fundamental property: a camera follows the pinhole model if and only if the projection of every ...

It is known from experiments that the radiated x-ray energy appears to exceed the calculated implosion kinetic energy and Spitzer resistive heating [C. Deeney, Phys. Rev. A 44, 6762 (1991)] but possible mechanisms of the enhanced x-ray production are still being discussed. Enhanced plasma heating in small-diameter wire arrays with decreased calculated kinetic energy was investigated, and a revi...

When using perspective cameras underwater, the underwater housing with its glass interface between water and air causes the light rays to change their direction due to refraction. In applications where geometrical properties of images are exploited without explicitly modeling refraction, i.e. when using the perspective pinhole camera model, this leads to a systematical error. This error is depe...

In this paper a novel camera model, the inversion camera model, is introduced, which encompasses the standard pinhole camera model, an extension of the division model for lens distortion, and the model for catadioptric cameras with parabolic mirror. All these different camera types can be modeled by essentially varying two parameters. The feasibility of this camera model is presented in experim...

Perhaps the simplest of biological timing systems, bacteriophage holins accumulate during the phage morphogenesis period and then trigger to permeabilize the cytoplasmic membrane with lethal holes; thus, terminating the infection cycle. Canonical holins form very large holes that allow nonspecific release of fully-folded proteins, but a recently discovered class of holins, the pinholins, make m...