Lasers in our lives 50 years of impact Lasers in our lives 50 years of impact The information in this brochure is just a sample of the significant social and economic impact that lasers have had on our lives over the past 50 years. Because of the collaborative nature of research many of the experiments, projects, R&D programmes, and applications that have led to the ubiquitous nature of lasers, have been joint efforts between research councils, academia and industry. The Science and Technology Facilities Council (STFC), through its Central Laser Facility based at the Rutherford Appleton Laboratory (RAL), continues to play a leading role in the development of lasers and operation of high- power laser facilities. The Engineering and Physical Sciences Research Council (EPSRC) is also a key funder of laser research and technology in the UK. This brochure was co-funded by STFC and EPSRC. Project Manager: Connor Curtis, STFC Design and layout: Ampersand Design Production: STFC Media Services Introduction What are lasers? Light Amplification by Stimulated Emission of Radiation 1 Lasers are concentrated A brief history Introduction beams of electromagnetic The conception of the laser traces back to a theory proposed by radiation (light) travelling in Albert Einstein in 1917. a particular direction. It was Einstein’s theoretical understanding of the interactions between light and matter that paved the way for the first laser. However, it was not until The defining properties of laser 1960 that the first working optical ruby laser was built by Theodore light are that the light waves are Maiman. Over the past 50 years, the laser has evolved considerably, and coherent (all travelling in harmony many new varieties have been developed. Due to their extreme versatility, with one another) and that they lasers have become invaluable tools across a multitude of applications. are usually of one wavelength, or colour. Where STFC fits into the picture By harnessing these properties in a device that reflects light back and The UK excels in research using and creating high-power lasers. forth through a special material, it is possible to generate an STFC’s Central Laser Facility (CLF), amplified light source, or laser. sited at the Rutherford Appleton Laboratory has been at the forefront Such light can be concentrated in of innovative laser technology and time and space to create truly research for more than 30 years. extreme conditions, or be used to This brochure demonstrates the far provide exquisite imaging and reaching impacts that lasers have on analysis capability across a wide our lives, and highlights some of the range of applications. key contributions made by STFC in the field of laser research during the past 30 years. Why do we care about lasers? Today, lasers impact almost every aspect 2 of life… …from medicine to Measurement Defence and Medicine manufacturing, from and analysis national security and health communications to Measurement and analysis The world is on high alert Only one year after its measurement, and from have been transformed by for potential terrorist invention, the laser was research and analysis to the laser. Surveyors use attacks, and security is of being applied in a entertainment. This is lasers to mark out roads high priority. Detecting medical procedure. This ironic for a device that and construction sites, the explosives and happened in December military use them to biochemical hazards are 1961 at the Columbia- was initially described as determine the position of just a few examples of Presbyterian Hospital, a ‘solution looking for a targets and even NASA how lasers can strengthen where a ruby laser was problem’. In fact, during has utilised lasers to our national security. used to destroy an eye measure the distance of tumour. Today, lasers are its first 50 years, the ➜ SEE PAGE 6 the Moon from the Earth. commonly employed in laser has been nothing most medical disciplines, Laser analysis of chemical including dermatology, short of revolutionary! and physical structures dentistry, cardiology, We can only wonder has allowed factories to neurosurgery and eye manage quality control what the next 50 years surgery, because of their efficiently. Laser will bring. ability to deliver high- techniques have been precision treatments, adopted by aluminium- whilst remaining manufacturing plants to minimally invasive. monitor accurately the Laser-based therapies proportion of constituent fact fact and diagnostic methods metals in alloys. They also represent an area of huge play a crucial role in the Estimates suggest The total number future potential. inspection of that the world market of laser patents ➜ for lasers in 2007 alone pharmaceuticals. issued since its SEE PAGE 8 was worth more than ➜ SEE PAGE 4 invention is well £4Bn! over 50,000 Lasers in our lives 50 years of impact 3 Environment Why do we care about lasers? Energy Communications and climate Manufacturing Lasers can generate Long-distance Climate change is one of Lasers are employed across extreme pressures and telecommunications and our most immediate the manufacturing industry temperatures, and so can be broadband internet both challenges. Deforestation as tools capable of used to ignite nuclear fusion depend on the transmission and the burning of fossil delivering intense cutting – the same process that of light pulses along optical fuels are the likely causes or welding power with powers our Sun. fibres. These light pulses for the increased high precision. Their ability are both generated and concentrations of to manipulate and Research into laser-driven relayed via lasers. This greenhouse gases in the transform materials makes fusion is currently revolutionary method of Earth’s atmosphere. them ideal for the underway and promises to communication is replacing automobile, computer and address our increasing Lasers can be used to less efficient copper wire- clothing industries – to demands for energy. analyse the concentrations based networks and is the name but a few. In fact, it of these gases and even to In addition, scientists are foundation of the internet is difficult to find a modern monitor their effects on exploiting lasers in the and information age. consumer product that has ecosystems. development of solar cells. not seen a laser during its ➜ SEE PAGE 12 ➜ SEE PAGE 14 manufacturing. ➜ SEE PAGE 10 ➜ SEE PAGE 16 Measurement and analysis 4 Photo: ESA Photo: ESA (NASA) Measuring the distance Do lasers hold the key to unlocking to the Moon the secrets of the Universe? Thanks to special mirrors left behind by The very fabric of space and time continually undergoes subtle Apollo astronauts, the distance from the ‘ripples’ that carry messages of astronomical events. These Earth to the Moon is known with a include the mergers of massive black holes, neutron stars and precision of millimetres! even the aftermath of the Big Bang. The ‘ripples’, or gravitational waves, were predicted almost a century Laser light fired from the Earth is reflected ago by Einstein’s General Theory of Relativity. Detecting and studying back by these mirrors (lunar retro-reflectors) them will provide an entirely new way to observe and understand and by accurately recording the time the the Universe. light takes to travel, the distance to the Moon can be determined. The Laser Interferometer Space Antenna (LISA) experiment aims to do just that. An ESA/NASA joint venture, LISA will consist of three separate, identical spacecraft flying in an equilateral triangle arrangement, with ‘laser arms’ about 5 million kilometres long. Tiny changes in the relative length of these arms caused by gravity waves will be measured by precisely monitoring the separation between each spacecraft. From studying the Photo: ESA (C.Vijoux) shape and timing of these waves, the LISA research team will be able to infer information about the astronomical systems that emitted them, such as their nature and evolution. Lasers in our lives 50 years of impact 5 Using lasers to Lasers in archaeometry Measurement and analysis measure gravity and art As well as being able to generate Non-invasive laser diagnostic techniques have been used to extremely high temperatures, lasers identify, date and analyse ancient artefacts, rocks and can also be used to cool down dinosaur fossils. atoms to temperatures close Archaeologists have also applied laser-scanning techniques to to absolute zero (-273°C). sites such as Stonehenge (Wiltshire, UK), leading to the When laser cooling is discovery of lost ancient art. combined with another In addition, lasers have technique called magneto- been employed to scan optical trapping, it is possible to and survey ancient sites, produce samples of trapped, slow- allowing archaeologists moving, neutral atoms that are close to to generate 3-D absolute zero. images and visualise Following research carried out by US their excavations physicists, scientists at STFC are now during its various working on a device that incorporates a stages. Lasers are also magneto-optical trap into a system being increasingly capable of measuring gravity to high used in the accuracy. By ‘dropping’ these cold atoms examination and down a vertical vacuum tube, precise conservation of gravitational measurements can be made. paintings and Such devices have potential applications artwork. in geophysics and in oil exploration. Defence and national security 6 Detecting chemicals Seeing through before it’s too late opaque bottles A system capable of remotely Spatially Offset Raman identifying, quantifying and Spectroscopy