Fiber Lasers are precise and efficient and are well suited to industrial applications ranging from high power cutting and welding to more delicate applications in semiconductor and solar manufacturing. Fiber-based lasers are modular and scalable allowing them to be configured for many processes from nanosecond engravers to many kilowatt CW (continuous wave) welding and cutting applications. Some CW lasers can also be modulated at kilohertz rates, a useful technique for reducing heat effects in the parent material.
High power fiber lasers use optical fiber as the gain medium and LED pumps. Fiber lasers provide consistent beam quality at all power levels. The laser beam is conveniently delivered to the terminal optics through a flexible fiber cable.
Fiber lasers do not have the typical mirrors and other delicate optics that may require periodic alignment. The conversion efficiency of wall plug power into laser energy is typically very high compared to other high power lasers. Fiber laser is simple to implement and operate and this fact makes them very robust and capable in industrial settings.
Fiber lasers are typically smaller and lighter in weight than traditional lasers. Conventional lasers can be quite delicate due to the necessity of precise alignment of mirrors and lenses.
Fiber lasers are much more rugged and able to perform in many different work environments. The fiber laser also transports easily without the need to re-align.
The fiber laser technologies result in high reliability and performance that are often superior to traditional laser technologies.
Applications for Fiber Lasers:
Cutting
Welding
Drilling
Etching
Marking
YAG Lasers
The YAG laser can provide very high power pulsed operation for welding, drilling and cutting.
A YAG laser can be coupled to a water-jet where the jet guides the beam to a surface, particularly for dicing, as in silicon wafers. The water jet removes debris and cools the material at the same time. Advantages of the YAG laser over traditional “dry” laser cutting are high dicing speeds, parallel sides in the kerf, and omnidirectional cutting.
YAG lasers are used in manufacturing for engraving, etching, or marking a variety of metals and plastics. They are extensively used for cutting and welding steel, semiconductors and various alloys.
For automotive applications (cutting and welding steel) the power levels are typically 1-5 KW. The drilling of super alloys, as for gas turbine parts, is commonly accomplished with YAG lasers. Other kinds of aerospace applications use YAG lasers to drill arrays of small holes for cooling and to produce desired high speed fluid flow characteristics.
YAG lasers are employed to make subsurface markings in transparent materials such as glass or acrylic glass.
Lasers up to 400 W are used for selective sintering of metals in additive layered manufacturing.
Applications for YAG Lasers:
Welding metals
Drilling and cutting metals
Drilling and cutting ceramics
Etching
Marking
CO2 Lasers
CO2 laser technology is well-proven in most industrial applications. CO2 lasers can be extremely reliable providing high up-time and excellent beam quality. CO2 lasers are essential tools for many industrial applications.
Common variations of CO2 lasers include fast axial flow, slow axial flow transverse flow and slab. CO2 lasers are commonly pumped by passing a current through the gas mix (DC-excited) or using radio frequency energy (RF-excited). The RF method is newer and has become more popular. Since DC designs require electrodes inside the cavity, they can encounter electrode erosion and plating of electrode material on glassware and optics. RF resonators have external electrodes and are not prone to these problems.
The Sealed-Off CO2 Laser
The optical resonator of this CO2 laser is formed by the front and rear mirrors and two parallel RF-electrodes. Excitation of the laser gas takes place in the RF field between the water-cooled electrodes. The heat generated in the gas is dissipated by the water-cooled electrodes (diffusion cooled). A beam shaping module is integrated into the laser head and produces a high quality round symmetrical beam. The sealed–off laser is most suitable for laser cutting, laser scribing, laser perforation or surface treatment.
CO2 lasers are used for industrial cutting of many materials including:
Mild Steel
Aluminum
Stainless steel
Titanium
Paper
Polymers
Woods
Wax
Fabrics
Applications for CO2 Lasers:
Cutting
Welding
Drilling
Etching
Marking
Pulsed Lasers
Lasers are classified as CW (continuous wave) or pulsed. Some CW lasers can be modulated to mimic pulsed laser operation.
The operational characteristics of pulsed lasers cover many orders of magnitude in both time and pulse power. A number of technologies are employed to address a number of widely different motivations.
Generally, the shorter the pulse produced by the laser, the higher the pulse power and the lower the pulse energy.
Cutting and welding requires melting a large volume of metal. High energy pulses are needed. Generally long pulses (milliseconds) are needed and the average power is on the order of a kilowatt.
Processes for surface modification, etching, engraving and marking usually require leaving the remaining material unaltered by heat. Changing the heat treatment state of metals, charring polymers and cracking brittle materials is undesirable. These processes generally require evaporating a tiny volume of material and therefore require only a tiny amount of energy, but it must be delivered at a time scale that is short enough to minimize or eliminate damaging heat transfer to the adjacent material.
Applications for Pulsed Lasers:
Engraving and marking of metals, ceramics, glass, plastics
Cutting thin materials without warping, can be a very fine process
Ultra-Short Pulse Lasers
Ultra short pulse lasers have pulse widths roughly between 100 femtoseconds and tens of picoseconds. At this time scale, heat effects in the parent material are minimized or even eliminated allowing fabrication of parts at or near full material properties. These processes are referred to as cold or a-thermal for this reason.
These lasers are used for demanding medical and industrial applications. Capable of being focused to very small spot size and delivering megawatt to gigawatt peak power these lasers can produce parts with very small features and excellent cut quality in a wide variety of materials.
Cold laser cutting and ablation with ultra short pulse lasers is one of the most promising technologies for demanding applications, especially in the medical, photovoltaic and semiconductor industry.
Sensitive materials such as nitinolshape memory alloys are routinely processed with high accuracy and excellent cut quality and post-processing may not be needed.
Femtosecond lasers also cut bio-absorbable polymers like polylactic acids or polyglycolic acids with high accuracy.
Features:
High Precision Processing
Little or No Thermal Damage
Cold Laser Cutting
Cold Laser Ablation of any Material from Low Melting Polymers to Difficult to Process Memory Alloys
