Proc. SPIE. 11042, XXII International Symposium on High Power Laser Systems and Applications
KEYWORDS: Defense and security, High power lasers, Medical research, Laser development, Computer simulations, Personal digital assistants, Gas lasers, Optical simulations, Defense technologies, Carbon monoxide
The authors have developed and executed the computer simulation code to analyze the energy distribution of gas mixture for CO laser by using Macintosh computer The details, such as dependences of energy distributions on electric field and gas mixture ratio are described in this paper below.
In this paper, we demonstrate an extremely low-concentrated solar-pumped laser (SPL) that uses a transversely excited fiber laser geometry. To eliminate the need for precise solar tracking with an aggressive cooling system and to considerably increase the number of laser applications, low-concentration factors in SPLs are highly desired. We investigate the intrinsic low-loss property of SiO<sub>2</sub> optical fibers; this property can be used to compensate for the extremely low gain coefficient of the weakly-pumped active medium by sunlight. As part of the experimental setup, a 40-m long Nd<sup>3+</sup>-doped SiO2 fiber coil was packed in a ring-shaped chamber filled with a sensitizer solution; this solution functioned as a down-shifter. The dichroic top window of the chamber transmitted a wide range of sunlight and reflected the down-shifted photons, confining them to the highly-reflective chamber until they were absorbed by the Nd<sup>3+</sup> ions in the active fiber. We demonstrated a lasing threshold that is 10 times the concentration of natural sunlight and two orders of magnitude smaller than that of conventional SPLs.
The authors have developed the computer simulation codes to analyze the effect of conditions on the performances of discharge excited high power gas flow CO laser. The six be analyzed. The simulation code described and executed by Macintosh computers consists of some modules to calculate the kinetic processes. The detailed conditions, kinetic processes, results and discussions are described in this paper below.
The new simulation code of high power discharge has successfully developed. The code is not executed by mainframe computer, PC, nor Macintosh, but by iPhones. The details, such as development environment and process are described in this paper below.
The simulation for high power application has been executed. The simulation has done not by the local computer
but in the “cloud” computing environment. Now, the authors apply the cloud computing environment to the high
power simulation. The details will be presented in the conference.
The performance of high power gas laser has been analyzed. The numerical analysis has been executed not by a single
computer but by the several Macintosh computers combined by Xgrid technology. The total computing power increases
in proportion to the number of computers.
Effects of electric and magnetic fields on the discharge characteristics of gas mixtures have been analyzed. A part of
Boltzmann transport equation is modified to process the addition of magnetic field. The differential equation is
transformed to difference equation for numerical processing. The effects are analyzed by the modified computer code.
Execution, transfer, storage and display of laser simulation have been improved. The technology of virtual machine has
been introduced to integrate different hardware and software environments. The same binary code for laser simulation is
executed in the integrated environments.
Simulation by cellular phones has been developed for discharge excited gas mixture. The simulation codes suitable for relatively small size of internal memories are described in Java programming language and executed by cellular phones.
Simulation for discharge exited gas flow lasers has been improved. The simulation codes are developed and executed by high performance programming technique and corresponding computer systems. The simulation performances are much superior to those by previous technique and systems.
Compact programs have been implemented to the information devices of PDA, personal digital assistants, in order to analyze the power distribution of discharge excited gaseous media. The simulation codes are cross-developed between Macintosh computers and PDA.
New simulation code has been developed for gas flow CO lasers by the combined computing technique of server-side and client-side processing. The input and output interfaces are processed on the client-side and numerical calculations are processed on the server-side.
Computer simulation codes for first-overtone CO laser have been developed. The codes are designed to be executed in distributed computing environment. Performance characteristics have been analyzed and compared with those of fundamental- band CO laser.
A new simulation code of CO laser has been developed for the recent distributed environment. The partial simulation code is transferred from the server and processed by the clients. The Java language which is independent on computer variation is introduced into the system description.
The simulation code for the analysis of CO laser has been adapted for the recent computer network environment. The workstations, personal computers (PCs), and Macintoshes (MACs) are linked to the network where the simulation is carried out by the fast back-end machine and the input/output interfaces are built in the front-end PCs and MACs. The typical example can be displayed in the Web homepage.
Computer models have been developed for the beam mode analysis of CO laser. The models are improved from the authors' previous one which was deduced from asymptotic method. In order to analyze by the variety of PCs (personal computers) and workstations, two types of computer codes have been developed. The compact code is described in language C, which can be compiled by most of PCs. The simple code is described in Mathematica, of which high- level mathematical functions are useful. Both codes are carried out under the same conditions and compared.
A simple and compact computer code for the output beam mode analysis of the CO laser has been developed. The theoretical model based on the asymptotic expansion is converted to the computer model, which is divided into smaller structural modules. The program is described in C language in order to be compiled and executed by PCs, Mackintoshes, and workstations. The beam mode profiles under the multiline operation and misaligned cavity conditions are analyzed.
Computer models have been developed for the industrial CO lasers, those are oparated by transverse dc discharge in the
temperature region 1 50-200 K. The 1D (dimensional) model has been developed to analyze and predict the output
performance characteristics, mainly the laser power. The flow equations are coupled with the kinetic equations of the
direct excitation by electron impact in discharge, V-V (vibration to vibration) and V-R/T (vibration to rotation and
translation) energy transfer by collision, and spontaneous and stimulated emission. The 2D model to analyze the spatial
distribution of the gas temperature and excited molecules is now under development. The flow equations, based on the
control volume method for the 2D Cartesian coordinates, are described. The time integration is performed by the
In order to simulate and predict the complex mechanism of the high power CO laser excited by transverse dc discharge, a two-dimensional gas flow model has been developed from the authors' one-dimensional model. Based on the control volume method for two-dimensional Cartesian coordinates, the fundamental equations deal with state, continuity, momentum, energy, and reactions. The similar discharge power distribution can be given as the experiment, where the power density is higher around the hollow-cathode array than around the plane anode. Although the speed of the CO gas mixture is in the sub-sonic region, the effect of compression is taken into account. The integration is repeated by SIMPLEST method and the matrices are solved by MICCG method for the pressure equation and by MILUCR method for the other equations. The computation is carried out by a HITAC S820 supercomputer and a Sun-4 workstation. As a result of the simulation, non-uniform distribution of the gas parameters was made clear.