A History of Fiber Lasers
For those history buffs out there or for those that are simply looking to understand a little bit more on how we’ve got to where we have today with fiber lasers, this is for you. In this article, we’ve laid out a much more detailed explanation of the history of fiber lasers, and given our own two cents on where the future of the industry may be heading.
Some background to lasers in general
It has to be said from the outset that fiber lasers do in fact have quite a long history, dating back to their invention in 1963 by Elias Snitzer. However, it took almost another two decades of development before fiber lasers were anywhere near ready for commercial production.
This has meant that fiber lasers are the newest type of laser process to hit the market, with their two main other counterparts being gas lasers, which usually use carbon dioxide or helium-neon, or crystal lasers, also known as an Nd:YAG (neodymium-doped yttrium aluminium garnet) laser.
Both of these two other laser processes were actually invented after the fiber laser, with the gas laser being invented in 1964 by Kumar Patel, and the crystal laser also in the same year by J. E. Geusic at the same laboratory as Dr. Patel; Bell Labs.
Bell Labs were very much the pioneers of all things lasers at this time, with numerous scientists making breakthrough discoveries that we’re still feeling the effects of today.
While fiber lasers took much longer to develop, the other two lasers were ready for action much quicker, and the gas laser remains the most commonly used type of laser today. However, the time it has taken to develop fiber lasers seems to have paid off, and it is generally agreed that this process offers more benefits than the other two types of laser processes. Frequent comparisons are made between fiber lasers and gas lasers.
The history of fiber lasers
Now that we’ve provided you with a brief history of lasers in general, we want to turn our focus specifically to fiber lasers. As mentioned, the laser itself was invented a long time ago, back in 1963, and took many years of development and iterations before it was anywhere near ready for commercial use.
However, even once they did hit the market almost twenty years later, they were still far from perfect. The first commercial fiber laser was useful, but not for the heavy industrial applications that we see it used for today.
They used single-mode diode pumping and were only able to emit a few tens of milliwatts. That’s not to say that this type of fiber laser didn’t have its uses, and many users were attracted by the single mode continuous wave beam that the new invention offered.
However, many laser applications at the time needed a much higher level of power output, with watts of optical power required as opposed to milliwatts. This increase in power output wasn’t seen until around 1990 when a fiber laser that was 4-W erbium-doped was invented.
This was a fundamental breakthrough in the development of fiber lasers as we know them today, and it helped to lay the groundwork for what would later become 10-watt fiber lasers and single-mode fiber lasers that were more powerful and more precise. These inventions became especially useful for micromachining and other applications which could truly make use of high-powered fiber lasers.
Modern Advances in Fiber Lasers
The fiber lasers that we know and love today feature a cladding pumping system, a concept that was first proposed back in the 1970s but didn’t come to fruition until many years later.
This system sees the single-mode fiber core surrounded by the cladding, which allows for the pumping of high-power multi mode diodes. This system means that multimode output radiation can be efficiently converted from a solid-state pump laser into one single, powerful emission of a fiber laser. This all happens inside the core of the fiber laser, helping to get maximum efficiency and power output with the laser beam that is emitted.
More iterations and improvements were made on this concept, more specifically a way in which a higher scaling of total power output was able to be achieved more practically.
It wasn’t long before these cladding-pumped fiber lasers were introduced to the commercial market and greatly helped with laser drilling, as well as low-end laser cutting of non-metal materials and low-end laser welding.
Although many of the applications that this type of fiber laser was able to complete were more high-end, it provided many benefits to users. These were:
- More efficient by around 20%
- More compact in nature
- Much better cooling system
- A lifetime that was greater than 30,000 hours
- Ability to work in industrial conditions requiring no maintenance
The benefits of fiber lasers was clear to all, and demand gained rapid momentum in the market for this new and innovative piece of machinery. But, people wanted more power outputs to engage in more industrial applications.
The modern day fiber laser
The improvements and advancements that many in the market were after were soon realised, and by 2000 a high-powered fiber laser was created that could be used in a wide ranging number of heavy applications.
Further developments have been made by combining the outputs of several fiber lasers. For example, seven fiber lasers with a 100-W power output are delivered using seven single-mode fibers but combined into a multi-fiber beam for added power and distance.
Some of the information from this article was sourced from a piece written in 2002, and while the developments that were discussed in here still form the foundations of the modern day fiber laser, the technology has continued to progress further in the last 15 years.
While the article spent much time talking about the power of a 100-W fiber laser, the power output has dramatically increased in recent years, and we’ve even just released two new sets of fiber laser that can achieve power outputs of up to 6kW.
The future of fiber lasers
It’s safe to say that we will continue to see many developments being made to fiber lasers in the upcoming years. They are already used in dozens of industries around the world and have become a staple part of the manufacturing process.
It’s likely that the improvements and the developments that we’ll see will happen much more frequently now, and scientists have even begun to explore how fiber lasers could be used to help build sustainable and habitable bases on Mars!
If you’re interested in fiber lasers and where the future might be headed, then watch this space…we’ll be bringing you all the most interesting and latest developments!
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