IPG Photonics

About: IPG Photonics is a based out in . It is known for research contribution in the topics: Laser & Fiber laser. The organization has 903 authors who have published 1241 publications receiving 63339 citations.

Compact Single Frequency Laser

Abstract: A single frequency laser system is configured with an elongated housing extending along a longitudinal axis and having opposite axially spaced upstream and downstream ends. The housing encloses a laser chip configured to emit a radiation which propagates along a light path and emitted through the downstream faucet thereof. One or more spaced frequency discriminators are mounted in the housing downstream from the chip so as to define an external resonant cavity with the upstream faucet of the of the laser chip. At least two or more separate thermoelectric coolers (“TEC”) are mounted in the housing to control the chip arid discriminators so that the system emits radiation at the desired frequency.

Structure of spinel at high temperature using in-situ XANES study at the Al and Mg K-edge

Abstract: We present structural information obtained on spinel at high temperature (298–2400 K) using in situ XANES at the Mg and Al K-edge. Spinel, [4](Alx,Mg1-x)[6](Al2-x,Mgx)O4, with increasing temperature, show a substitution of Mg by Al and Al by Mg in their respective sites. This substitution corresponds to an inversion of the Mg and Al sites. Furthermore, both experiments at the Al and Mg K-edges are in good agreement with XANES calculation made using FDMNES code.

Preliminary results of lava flow mapping using remote sensing in Piton de la Fournaise, La Réunion island

Abstract: The use of remote sensing is more and more incontrovertible in volcanic monitoring, especially in INSAR and thermal studies. A comprehensive database of high-resolution multispectral and multitemporal optical satellite imagery exists for Piton de la Fournaise, the active volcano on La Reunion Island. This database, however, remains relatively underexploited in volcanological studies of Piton de la Fournaise. Using a large image data set including SPOT 5 and 4, ASTER and aerial photography, we performed cartography of recent lava flows. Different methods were applied for each sensor in order to extract and map lava flow contours and surface morphology. These methods include photo interpretation as well as fusion of thermal band and optical images. In addition we performed several tests with specific software combining object and spectral based techniques. Subsequently, a simple statistical comparison between different perimeters and areas mapped allowed us to determine a precision ratio. Results show that difficulties in extracting contours arise when the study area is a complex lava flow field where the different lava flows overlap, or have a similar textural and radiometric characteristics.

High Power Spatial Filter

Abstract: An improved high power special filter, system and method. In the system, an optical fiber is disposed inside a ferule channel structure, and the channel structure is aligned with a focusing lens system. The end of the fiber is at a distance D from the channel opening that faces the focusing lens system, and D is determined by the system's numeric aperture factor and the cladding thickness of the optical fiber.

Thermodynamics: The Oldest Branch of Earth Sciences?

Abstract: All geological changes result from the transfer of matter and energy, the study of which is the goal of thermodynamics. Investigating natural processes thus necessarily involves thermodynamic considerations. This has long been practiced implicitly, as shown by the smart reflections made by “natural philosophers” from antiquity to the 18th century about topics ranging from atmospheric phenomena to the early history of the Earth. Since the early 19th century, investigations explicitly take advantage of a rigorous framework that deals with chemical and thermal aspects of the Earth's activity. Far from being abstruse, these principles can in fact be summarized in a simple and concise way.