JLA Vol:1 Iss:3 (CO₂ Laser Engraving System for Relief Plate to Print Corrugated Cardboard)

Authors:
K. Wakabayashi
N. Sugishima
NEC Corporation, Laser Equipment Div., 1120, Shimokuzawa, Sagamihara, JAPAN

A very compact and economical CO₂ laser engraving system to make relief plates for the purpose of printing corrugated cardboard has been developed. This system consists of a highly stable 500W CO₂ laser and a high speed, easy handling image processing sub‐system. In this paper several new developments are described. This image processing technique for CO₂ laser raster scanning and engraving has been newly developed. Every binary image is converted to the relief plate more easier than other reported engraving systems.

JLA Vol:1 Iss:3 (Complete Particle Field Characterization with Optical Diagnostics)

Authors:
W. D. Bachalo
Aerometrics, Inc., Sunnyvale Technology Center, 894 Ross Drive, Unit 105, Sunnyvale, CA 94089

A discussion of the practical aspects of particle sizing using light scatter detection is presented. The primary focus is on single particle counter methods for performing in situ size and velocity measurements. One objective of the presentation is to provide information on the applicability and limitations of these methods when measurements in practical environments are required. The problem of dealing with irregularly‐shaped particles is considered. Light scattered by such particles is not easily analyzed except in the near‐forward direction. Examples o...

JLA Vol:1 Iss:3 (Experimental Laser Welding Thermal Cycles)

Authors:
E. A. Metzbower
U.S. Naval Research Laboratory, Code 6324, Washington, DC 20375‐5000, U.S.A.

JLA Vol:1 Iss:3 (Experimental Laser Welding Thermal Cycles)

Authors:
E. A. Metzbower
U.S. Naval Research Laboratory, Code 6324, Washington DC 20375‐5000, U.S.A.

JLA Vol:1 Iss:3 (Laser Welding of Plastics in Low and High Gravity Environments)

Authors:
R. E. Mueller
W. W. Duley
CRESS and Laser Processing Laboratory, York University, Toronto, Ontario, Canada M3J 1P3

S. MacLean
M. Garneau
B. Tryggvason
Canadian Astronaut Office, National Research Council, Ottawa, Ontario, Canada K1A 0R6

W. F. J. Evans
Atmospheric Environment Service, 4905 Dufferin Street, Downsview, Ontario M3H 5T4

Initial results of a series of laser processing experiments performed under the micro‐gravity conditions supplied by NASA's KC‐135 aircraft are presented. Weld morphologies of polypropylene and polyethylene were obtained under both hyper‐ and hy...

JLA Vol:1 Iss:3 (Performance of a Broadband Free‐Electron Laser and Preliminary Studies on Its Application to Biology and Medicine)

Authors:
Stephen Benson
John Madey
Dept. of Physics, Duke University, Durham NC 27706

Richard Straight
Brett Hooper
Utah Laser Institute, Department of Veterans Affairs and the University of Utah Medical Centers, Salt Lake City, Utah 84148

Recent performance improvements in the free‐electron laser (FEL) have allowed it to operate at a level suitable for most applications in laser medicine. A brief description of the operation of a free‐electron laser will be presented. The performance desired in a medical FEL will be described and the performance to date of the Mark III mid‐infrared to visible FEL at Stanford Univer...

JLA Vol:1 Iss:3 (Simultaneous Laser Velocimeter and Concentration Measurement)

Authors:
David T. Walker
William G. Tiederman
School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47907, U.S.A.

Inability to predict the high Schmidt number mixling of a concentrated polymer solution injected into a channel flow of water motivated the development of a method for measuring the product of the velocity fluctuation normal to the wall and the fluctuation in the polymer concentration. Time‐resolved concentration measurements were obtained using a laser‐induced fluorescence technique. The injected fluid was marked with a fluorescent dye and the spatial distribution of the intensity of fluorescent light emitted from an argo...

JLA Vol:1 Iss:4 (FDA Medical Incident Report Is Sobering Reminder of Laser Safety Education Needs)

Authors:

JLA Vol:1 Iss:4 (Installation of a Commercial Excimer Laser in the Operating Room)

Authors:
H. Benoit
J. Clark
W. J. Keon
University of Ottawa Heart Institute, Ottawa Civic Hospital, Ottawa, Ontario, K1Y 4E9

A multi‐use commercial excimer laser was modified for use in the cardiovascular operating room. The laser was originally designed for research and laboratory applications and required on‐site development to become acceptable for the clinical environment. Particular care was taken to control the associated hazards of toxic gas storage, handling and disposal. Resolution of problems relating to line isolation and leakage currents, design of administrative and engineering controls for laser and associated hazards, safety and ...

JLA Vol:1 Iss:4 (Laser Accidents: Are They All Reported and What Can Be Learned from Them?)

Authors:
R. James Rockwell
Rockwell Laser Industries, Cincinnati, Ohio