If one reviews what happened in the first 50 years of the laser’s history, it becomes quite a challenge to predict what will happen in the next 50. Lasers went from being called “a solution in search of a problem” to becoming an integral part of many aspects of our daily lives. Today, lasers are used for diverse applications in fields such as materials processing, telecommunication, medicine, defense, science and astronomy, sensor technology, data storage and entertainment. Within the first few years of the laser’s invention five decades ago, many of the types of lasers that we use today had already been demonstrated. The future starts yesterday No matter how many new laser types are developed in the future or how many additional applications are found, a few advancements are inevitable because certain trends have been in the pipeline for quite a while. Lasers will continue to become smaller and more compact, more efficient, and lower in cost in terms of investment and operation. They also will become even more reliable than they are today and will require less maintenance. These developments will pave the way for new applications and make it possible for applications already being discussed to become financially and/or technologically feasible. The expansion of the range of all laser characteristics – such as power, pulse energy, wavelength and pulse length – and the ever-increasing level of integration of components within a laser and of lasers into other devices, will open the door for new applications. Questions and more questions More specific questions about the future of laser technology are, of course, difficult to answer definitively. Here are a few to think about: Will we see completely new laser types, or primarily modifications and improvements of technology that already exists? Will barriers to other technologies first have to be overcome for laser technology to take the next step? One possible challenge that comes to mind, for example, is battery technology that might be required for mobile laser applications. Will safety issues have to be resolved before lasers can be deployed in unusual or less-controlled environments? Will completely new laser applications evolve? Or will we simply see modifications and improvements to existing applications? New new? New old? Or both? Many researchers are working to replace the laser technology that already exists. One example is the use of lasers in picoprojectors, allowing devices such as smart phones not only to take pictures but also to project them and other documents onto a screen. Researchers also are developing the next generation of laser technology for existing applications. In industrial production, lasers are being used to produce extreme-ultraviolet (13.5 nm) wavelengths that are enabling the continuation of Moore’s Law – the doubling every two years of the number of transistors on an integrated circuit. Industry is focused also on decreasing photolithographic feature size. Yet another evolving sphere is optical computing. A significant amount of research is happening in this field, and the collaboration of scientists and engineers might one day lead to a completely new level of computing. Light, in contrast to electric current, does not produce heat, which is a limiting factor in increasing processing speed. Because light beams, unlike traces for electric current, can cross without interacting, optical computing could provide alternate options for the layout of circuit boards. The future looks bright – and interesting In addition to the applications that are almost certain to become a reality is the long list of possible applications that most people living in the year 2010 would classify simply as, shall we say, “over the top.” In this futuristic category, the most predominant ideas are probably best summarized by the term “laser weaponry.” Although some applications, such as the neutralization of surface land mines, already exist, more are to come. Interestingly enough, in the early days, laser beams were labeled by some researchers as death beams and, starting in the 1960s, were used as such in science fiction movies. Another application possibility is power beaming. The concept behind this is that laser beams transport energy to places that are not easily reached via conventional methods. Examples include supplying energy to remote military camps or to a zeppelin (airship) stationed above a specific area for observation tasks. The space elevator is another project on the horizon. A laser is used to deliver energy to a climber that travels up into space along a tether suspended from a satellite. An international space station already exists; if a space elevator is developed, it will facilitate access to other planets. At that point, lasers might be used for interplanetary communication. And while we’re on the topic of space-related applications, we should mention that lasers potentially could be used to beam power down from space to Earth, using energy generated by solar cells stationed in space. Another activity related to energy generation is one of the largest laser projects currently in development. At the National Ignition Facility, the beams of 192 lasers are focused onto a target composed of hydrogen to fuse the hydrogen atoms’ nuclei and to produce energy. If successful, this could be a major component of solving the energy problem. If the trends mentioned above are far-reaching enough, it might be possible not only to have laser pointers in a Swiss army knife, as we do today, but also even to replace the stainless steel blade with a laser blade. Just imagine the possibilities for a moment: You could cut down that tree in your backyard with a laser. Now that we’ve speculated about the potential for future laser applications, let’s take a look at the lasers themselves. Laser diodes certainly will increase in power, and we’ll see dramatic improvements in their beam quality. Lasers that are widely discussed today, such as fiber and disk types, will be replaced by direct diode systems for many applications. And new materials such as nanopowders might lead to the development of entirely new laser types altogether. While there are many unknown aspects regarding the future of laser technology, one thing remains certain: The possibilities are endless. As in the past, it is unlikely that we’ll see the one single laser that can perform every application requiring one. And as a laser guy, I really hope that no technology replaces the laser in the way that the laser has replaced other technologies. However, if I could gaze into a crystal ball for a moment and make a prediction, I’d have to say that it’s a pretty safe bet that lasers will be around long after I’m gone. Meet the author Jochen Deile is the manager of new laser products for Trumpf Inc. in Farmington, Conn.; e-mail: jochen.deile@us.trumpf.com.