Recently much attention has been paid by horticulturists to light-emitting diodes as a new source of economical and spectral-selective light. The reason is mainly coming from their versatility in handling and mounting, long working time, wattage use efficiency and lower heat production. In this study we examined their potential in promoting seed germination and producing quality flower seedling...

GRB980519 is characterized by its rapidly declining optical and X-ray afterglows. Explanations of this behavior include models invoking a dense medium environment which makes the shock wave evolve quickly into the sub-relativistic phase, a jet-like outflow, and a wind-shaped circumburst medium environment. Recently, Frail et al. (1999b) found that the latter two cases are consistent with the ra...

The Linac Coherent Light Source (LCLS) at the SLAC National Accelerator Laboratory was the first hard X-ray free-electron laser (FEL) to operate as a user facility. After five years of operation, LCLS is now a mature FEL user facility. Our personal views about opportunities and challenges inherent to these unique light sources are discussed.

Common tasks related to image processing or augmented reality include rendering new objects into existing images, or matching objects with unknown illumination. To facilitate such algorithms, it is often necessary to infer from which directions a scene was illuminated, even if only a photograph is available. For this purpose, we present a novel light source detection algorithm that, contrary to...

We present a light position calibration technique based on a general arrangement of at least two reflective spheres in a single image. Contrary to other techniques we do not directly intersect rays for triangulation but instead solve for the optimal light position by evaluating the image-space error of the light highlights reflected from the spheres. This approach has been very successful in th...

Combining the molecular specificity of the infrared spectral region with high resolution microscopy has been pursued by researchers for decades. Here we demonstrate infrared supercontinuum radiated from an optical fiber as a promising new light source for infrared microspectroscopy. The supercontinuum light source has a high brightness and spans the infrared region from 1400 nm to 4000 nm. This...

SPEAR 3 is an upgrade of the 18-cell SPEAR 2 storage ring to 3GeV beam energy, 18nm-radian emittance and up to 500mA circulating current. The existing arrangement of photon beam lines remains largely unchanged, but opportunities arise for additional ID and dipole radiation exit ports. For optimum beam stability, the entire tunnel floor will be excavated and replaced with reinforced concrete. Th...

The art of imparting information onto a light wave by optical signal modulation is fundamental to all forms of optical communication. Among many schemes, direct modulation of laser diodes stands out as a simple, robust, and cost-effective method. However, the simultaneous changes in intensity, frequency, and phase have prevented its application in the field of secure quantum communication. Here...