Electronics Protection - March/April 2012 - (Page 28)

Application Feature Coherent Integrates Marway’s Power Distribution Solution into Energy-Efficient, Direct-Diode Laser System Design Dave Proli, Engineering Manager Marway Power Solutions When one thinks about medical products, automotive components or even miniature models used in movies, lasers aren’t the first thing that usually comes to mind. However, these high-powered beams of light are vital to the successful processing of materials used in a myriad of products consumed around the world. Founded in 1966, Coherent, Inc. is a provider of lasers and laser-based solutions for scientific, commercial and industrial customers competing in the most demanding markets. Coherent has production and research facilities spanning the globe supplying laser systems and components, laser measurement and control products, and precision optics to over 80 countries. Notably, many of its customers are Fortune 500 manufacturers and scientific researchers from numerous universities and institutes across the Americas, Europe, and Pacific Rim. Recently, Coherent developed prototypes for its next generation HighLight 8000D direct diode laser system. This system was designed specifically for the needs of industrial materials processing including cladding, heat treating, and welding. The challenge was to design the new product with fewer discrete components, high energy efficiencies, and low maintenance time. The diode laser is a semiconductor device that directly converts electrical energy into laser light. Typically, higher power diode lasers output light in the near infrared, most commonly at either 808 or 980 nanometers (nm). A typical individual diode laser emitter might produce at most a few Watts of output power. However, numerous emitters can be fabricated on a single, monolithic semiconductor substrate or bar with a total output as high as 100 Watts. These linear bars can, in turn, be combined in horizontal and vertical stacks to produce highpower, direct-diode laser systems with total output power in the multi-kilowatt range. The maximum conversion efficiency of transforming input electrical energy into light in diode laser bars is about 59 percent, which is many times higher than for any other laser type. This includes CO2, lamp-pumped solid-state (LPSS), diodepumped solid-state (DPSS), and even fiber lasers.The primary benefit of higher efficiency is that it lowers the operating cost of the system since less electricity is required to produce a given amount of output power. Of course, this reduced power consumption also decreases the carbon footprint of the laser’s operation. The small size of diode lasers means that they produce their waste heat in a relatively small physical area. As a result, they can be effectively cooled with a small volume of circulating water and a chiller. In the past, direct diode lasers were more expensive to build and not energy efficient enough for mainstream use. Over the last five years, thanks to smarter components and research and development conducted at Coherent’s 28 labs, its new direct-diode laser systems produce much more light than previous diode lasers and can reach energy efficiencies of up to 50 percent. This efficiency is measured by comparing how much power is drawn (from the wall) with how much light comes out of the laser. Reaching 50 percent energy efficiency is a substantial achievement for direct diode lasers, and provides customers with a more attractive laser solution. Another key achievement is the laser’s shorter wavelength of 975 nm compared with CO2 lasers, which have a wavelength of 10 micrometers. The absorption of light into metals at 975 nm instead of at 10 micrometers is 3 to 5 times better. This allows more localized light interaction with the material while generating less heat in the part being created. The result is reduced distortion in the manufactured part, and significantly reduced scrap. In addition, due to the better absorption, the laser light is used more efficiently, consuming less energy. Often times this qualifies for government-funded, energy-reduction, tax benefits. This technical advancement will allow Coherent to serve a wider range of applications. Coherent’s HighLight 8000D (Figure 1), with output power of 2, 4, 6, or 8 kilowatts at 975 nanometers, is a powerful, industrial, direct-diode laser system with free-space beam delivery. Free-space beam delivery preserves the inherent brightness of the diode laser source, and enables the use of an optical system with a large (~275 mm) working distance. Together, these factors translate directly into enhanced laser capabilities in industrial processing applications. Specifically in cladding, it yields a higher material deposition rate (up to 18 pounds/hour), allowing the laser to “paint-on” metal. Increased production speed enabled new benchmark levels in Figure 1. Coherent’s new both cladding and heat treating HighLight 8000D series Direct due to the laser’s higher power Diode Laser and longer-line beams, which allow processing of larger areas in a single pass. The laser is comprised of the laser head, laser control unit (LCU), which consists of a DC power supply and power distribution unit, and a chiller. A cable is connected from the three-phase, 480-watt, power outlet (or 400 watt in Europe/ Asia) to the LCU where the power is stepped down to create lower power at a higher current. “In the new design, I wanted to contain all the power tasks into one box instead of having discrete parts,” said Jussi Ylanen, Coherent’s project engineer for the HighLight D-Series. Newest Laser Technology Comes to Market Diode Laser Construction March/April 2012 www.ElectronicsProtectionMagazine.com http://www.ElectronicsProtectionMagazine.com

Table of Contents for the Digital Edition of Electronics Protection - March/April 2012

Electronics Protection - March/April 2012
Surge Stopper Shields Electronics From Transients Beyond 100 V
The Lowdown on IP Codes – Ingress Protection of Electrical Products
A Case for Safety - AC Arc Fault Circuit Interruption for PV Systems with Microinverters or AC Modules
Enclosure Design: IVC’s new Lightweight Explosion-Proof Camera Enclosure System
Portable Shock and Vibration Protection
Polycase Offers New Options for NEMA 4X Plastic Enclosures
New Circuit Board Shielding from Leader Tech
Laird Technologies Releases new Liquid Cooling Systems Product Line
ASI Releases New UL489 Hydraulic Magnetic Circuit Breakers
PEM C.A.P.S. Captive Panel Screws Offered in Three Mounting Styles26
SolarFocus Releases new SolarKindle Case
Indsutry News
Coherent Integrates Marway’s Power Distribution Solution into Energy Efficient, Direct-Diode Laser System Design

Electronics Protection - March/April 2012