JLA Vol:7 Iss:2 (Laser processing centers and their research projects in Japan)

Authors:
Akira Matsunawa
Welding Research Institute, Osaka University, 11‐1 Mihogaoka, Ibaraki, Osaka 567, Japan

In Japan, R&D activities on laser materials processing are mainly conducted in universities, public research institutions, and technical centers in private enterprise. Among them the Welding Research Institute and the Department of Welding and Production Engineering, both at Osaka University, have taken the initiative in conducting fundamental studies on laser materials processing as well as training experts and engineers in laser technology since the mid 1960s. In 1990, a new laser center called the Applied Laser Engineering Center (ALEC) was established in Naga...

JLA Vol:7 Iss:2 (Fraunhofer‐Institut fu¨r Lasertechnik)

Authors:
Eckhard Beyer
Fraunhofer‐Institut fu¨r Lasertechnik, Aachen, Germany

JLA Vol:7 Iss:2 (Fraunhofer resource center for laser technology ‐ USA)

Authors:
Frank W. Kuepper
Fraunhofer Resource Center for Laser Technology, Ann Arbor, MI, U.S.A.

JLA Vol:7 Iss:2 (Laser and optics activities at CREOL)

Authors:
C. Martin Stickley
Center for Research and Education in Optics and Lasers (CREOL), University of Central Florida, Orlando, FL, U.S.A.

JLA Vol:7 Iss:2 (High‐speed photographic studies of laser drilling of ceramics and ceramic composites)

Authors:
S. Ramanathan
M. F. Modest
Department of Mechanical Engineering, The Pennsylvania State University, University Park, PA 16802, U.S.A.

High‐speed photographic techniques were used to study plumes generated above a material during drilling of ceramics and ceramic composites with a carbon dioxide laser. The prinicipal objectives were to identify the mechanism of material removal (spattering, particulate and fiber debris, liquid droplets) and plume phenomena (plume shapes and sizes) for ceramics and ceramic composites. High‐speed photographic (1000 frames per second) visualization of laser drilling was undertaken for two monolithic ceramics, (sintered &...

JLA Vol:7 Iss:2 (Hazardous emissions: characterization of CO₂ laser material processing)

Authors:
H. Haferkamp
M. Goede
K. Engel
J.‐S. Wittbecker
Laser Zentrum Hannover e.V., Hollerithallee 8, D‐3000 Hannover 21, Germany

Parallel to the growth of laser technology is a high interest in safety in industrial surroundings. The characteristics of hazards resulting from laser processing are complex and highly interdependent. In addition, very little fundamental scientific research on this topic exists. The Laser Zentrum Hannover e.V. (LZH) is working on a research project subsidized by the BMFT (German Federal Ministry for Research and Technology) concerning the characterization and reduction of hazardous emissions resulting ...

JLA Vol:7 Iss:2 (A study of polarization‐maintaining fiber characteristics with applications to force and displacement sensing)

Authors:
P. V. P. Yupapin
K. Weir
K. T. V. Grattan
A. W. Palmer

An experimental investigation of three different types of highly birefringent fiber sensor element configured as a force and a displacement sensor is described. From the coupling of power between the two eigenmodes, the magnitude of the force and the position of the coupling point can then be determined using ‘white‐light interferometric’ techniques.

JLA Vol:7 Iss:2 (Understanding laser hazard evaluation)

Authors:
Wesley J. Marshall
U.S. Army Center for Health Promotion and Preventive Medicine (Provisional), Aberdeen Proving Ground, MD 21010‐5422, U.S.A.

The current 1993 version of the ANSI Z136.1 standard for the safe use of lasers provides maximum permissible exposures which more closely match available biological injury data. Interpreting the standard can be more difficult at times than with previous versions. By keeping the biological injury mechanism in mind, the reasoning behind the multitude of rules contained in the standard are more understandable.

JLA Vol:7 Iss:3 (Institut fu¨r Strahlwerkzeuge (IFSW), University of Stuttgart)

Authors:
Helmut Hu¨gel
Institut fu¨r Strahlwerkzeuge, University of Stuttgart, Pfaffenwaldring 43, D‐70569 Stuttgart, Germany

JLA Vol:7 Iss:3 (Institut de Soudure Laser Center)

Authors:
J. C. Goussain
A. Chehaibou
Institut de Soudure, 4 Boulevard Henri Becquerel, 57110 Yutz, France