White-light emitting diode lamps for general illumination can be realized by a combination of a blue light-emitting diode semiconductor die and phosphors. Newly developed oxynitride and nitride phosphors are promising candidates for this application because they have suitable excitation and emission wavelengths and stable optical properties in a high temperature environment. High brightness war...

Wheat (Triticum aestivum L. cv Fremont) grown in hydroponic culture under 24-hour continuous irradiation at 560 to 580 micromoles per square meter per second from either metalhalide (MH), high pressure sodium (HPS), or low pressure sodium (LPS) lamps reached maturity in 70 days. Grain yields were similar under all three lamps, although LPS-grown plants lodged at maturity. Phenylalanine ammoni...

In this paper, a number of different application fields of inorganic luminescent materials are being discussed. In a tutorial manner, it will be shown how device requirements are being translated into properties the luminescent materials need to have. To this end many different material properties that have a strong influence on the device performance are discussed, such as the shape, the spect...

Introduction: Very low, Low and Medium X-ray machines are used extensively for Superficial Radiation Therapy mostly used for Basal Cell, Squamous Cell Carcinoma, and Melanoma skin cancers. In most of cases, Superficial X-ray Therapy (SXRT) is preferred to Electron beams generated using a linear accelerator. SXRT tube characteristics may vary with the use of the machine for a lo...

In the recent years many authors [1-4] are working to obtain single stage HPF electronic ballast for fluorescent and HID lamps to obtain cost reduction and to comply with international standard requirements. Usually to obtain HPF in electronic ballast for high pressure sodium lamps a Power Factor Preregulator (PFP) is used between the mains and the electronic ballast [5]. In this paper will be ...

We present a novel method for the autonomous positioning of surgical lamps in open surgeries. The basic idea is to use an inexpensive depth camera to track all objects and the surgical staff and also generate a dynamic online model of the operation situs. Based on this information, our algorithms continuously compute the optimal positions for all surgical lamps. These positions can then be comm...

Fluorescence microscopy requires high photon-flux densities in the specimen plane. These intensities are only achieved by lasers, arc lamps, and, most recently, light-emitting diodes (LEDs). Lasers and LEDs, however, are restricted to a limited number of wavelength regions, whereas with arc lamps it is possible to select arbitrary wavelengths and wavelength regions. Moreover, the lower cost of ...