Photonics and Quantum Sciences News
April 2013: New camera system creates high-resolution 3-D images from up to a kilometre away
A team of Heriot-Watt physicists has advanced laser technology so that high-resolution, 3-D images precise to the millimetre can be taken from up to a kilometre away.
While a standard camera takes flat, 2-D pictures the team obtains 3-D information, such as the distance to a far-away object, by bouncing a laser beam off the object and measuring how long it takes the light to travel back to a detector. The technique, called time-of-flight (ToF), is already used in machine vision navigation systems for autonomous vehicles and other applications, but many current ToF systems have a relatively short range and struggle to image certain objects.
Ultimately it has the potential to scan and image objects located as far as 10 kilometre away
Dr Aongus McCarthyLed by Professor Gerald Buller from the School of Engineering and Physical Sciences, the Heriot-Watt team has developed a new system that captures laser pulses from ‘uncooperative’ objects that do not easily reflect laser pulses, such as fabric, making it useful in a wide variety of field situations. The new system works by sweeping a low-power infrared laser beam rapidly over an object. It then records, pixel-by-pixel, the round-trip flight time of the photons in the beam as they bounce off the object and arrive back at the source. The system can resolve depth on the millimetre scale over long distances using a detector that can ‘count’ individual photons. The primary use of the system is likely to be scanning static, human-made objects, such as vehicles. With some modifications to the image-processing software, it could also determine their speed and direction.
Dr Aongus McCarthy, Research Fellow at Heriot-Watt University said “Our approach gives a low-power route to the depth imaging of ordinary, small targets at very long range. “While it is possible that other depth-ranging techniques will match or out-perform some characteristics of these measurements, this single-photon counting approach gives a unique trade-off between depth resolution, range, data-acquisition time and laser-power levels.”
The scanner is particularly good at identifying objects hidden behind clutter, such as foliage. However, it cannot render human faces, instead drawing them as dark, featureless areas as, at the long wavelength used by the system, human skin does not bounce back a large enough number of transmitted photons to obtain a depth measurement.
The light the team has chosen has a wavelength of 1,560 nanometres, longer, or ’redder’, than visible light, and thus it travels more easily through the atmosphere, is not drowned out by sunlight, and is safe for eyes. Many previous ToF systems could not detect the extra-long wavelengths that the team's device is specially designed to sense. Outside of object identification, photon-counting depth imaging could be used for a number of scientific purposes, including the remote examination of the health and volume of vegetation and the movement of rock faces, to assess potential hazards.
Ultimately, McCarthy says, it has the potential to scan and image objects located as far as 10 kilometre away. “It is clear that the system would have to be miniaturised and made more rugged, but we believe that a lightweight, fully portable scanning depth imager is possible and could be a product in less than five years.”
For more information please contact the head of institute Prof. Gerald Buller.
March 2013: Heriot-Watt University leads EPSRC Centre for Innovative Manufacturing in Laser-based Production Processes
A new £12m national centre, led by Heriot-Watt University, will develop new ways of using lasers in manufacturing, enabling industry to take advantage of the latest innovations and developments in this rapidly growing field.
Laser-based manufacturing is a global multi-billion dollar industry with significant business opportunities. The past 25 years have seen industrial lasers replace many 'conventional' tools in many diverse areas of modern manufacture, enabling increased productivity, functionality and quality.
The Heriot-Watt University-based EPSRC Centre for Innovative Manufacturing in Laser-based Production Processes, supported by £5.6m of funding from the Engineering and Physical Sciences Research Council (EPSRC) and £4.8m from UK manufacturing industry and involving other key UK research centres and industrial partners, will open the door to a diverse range of new laser-based production processes and technologies, helping UK industry to take maximum advantage of these major advances by bringing together a multi-disciplinary team of leading UK researchers and key industry partners.
A major goal of the new Centre is to double the use of lasers in UK manufacturing industry in the next five years.
Prof. Duncan HandThe Centre's team of leading academics and UK industry partners will run a wide-ranging programme of coordinated research and network building which will enable significant business growth opportunities, stimulate the broader UK community, provide leadership in developing public policy, infrastructure access for SMEs, and education and training for the industry.
Professor Duncan Hand, Director of the new Centre, said, "Lasers have a major role in high value production, and are essential tools for a developed economy such as the UK to successfully compete on the world manufacturing stage. Laser processes provide high quality, high precision readily-automated manufacturing solutions, with excellent repeatability whilst retaining a high degree of flexibility, which allows mass customisation and design modifications."
EPSRC’s Chief Executive, Professor David Delpy said, “EPSRC Centres of Innovative Manufacturing are building on previous investments we have made in the research base and combining academic innovation with industry knowledge. These new centres are in areas that are strategically important to the UK and the work there will push research boundaries and drive growth."
For more information please contact Prof. Duncan Hand.
November 2012: Scottish-based researchers’ breakthrough set to scupper online fraudsters worldwide
Using quantum physics and tiny light particles to foil hackers and online criminals may sound like the stuff of Bond movies and sci-fi thrillers, but scientists have now successfully demonstrated how to protect finance, retail and other sectors from crippling e-crime. Physicists at Heriot-Watt University (Edinburgh, UK) and University of Strathclyde (Glasgow, UK) have worked with tiny particles of light to create a new way of verifying electronic messages and transactions as authentic, helping address the huge cost of e-crime (£205.4 million in 2011/12 for the UK retail sector alone) and avoiding potentially catastrophic fraud, online hacking and theft of digital data.
The work, published in the journal Nature Communications, shows how the fundamental particles of light, known as photons, can be used to verify security and authenticity of any transaction or communication with a ‘digital signature’.
Our new approach, using quantum mechanics rather than just maths to create signatures could make hacking, fraud and theft near-impossible.
Prof. Gerald BullerCurrently, ‘digital signatures’ underpin internet shopping, electronic banking, electronic voting and many software updates. Whenever the padlock symbol is displayed in a web browser, digital signatures are in use. However, with traditional online security, these signatures are based on mathematical formulae – and can be cracked, leading to fraud and other online security breaches. Quantum digital signatures use a different approach which ensures authenticity and origin of messages.
Gerald Buller said, “Computer virus attacks have shown that ‘signatures’ or specific codes can be hijacked, potentially causing chaos with systems being crippled, accounts hacked, and industry and consumers losing millions of pounds. Our new approach, using quantum mechanics rather than just maths to create signatures for multiple recipients (or customers), and could make hacking, fraud and theft near-impossible.”
Recent estimates of the value of 2011 online UK retail sales are at minimum £25 billion (according to the Office of National Statistics) and could be as high as £50.34 billion (Centre for Retail Research, 2011).
E-crime is the biggest emerging threat to the retail sector as the rapid growth in e-commerce in the UK sees new ways of shopping being accompanied by new types of crime, according to the British Retail Consortium’s recent report. Launching this report in August, BRC Director General Stephen Robertson said: “The rapid growth of e-commerce in the UK shows it offers great benefits for customers but also new opportunities for criminals.... resources must be directed to e-crime in line with the emerging threat. This will encourage retailers to report more offences and allow the police to better identify and combat new threats.”
Quantum-based secure signatures mean that an ‘eavesdropper’ – a malevolent third party listening in – cannot fake a signed message which is being sent to multiple recipients.
The research was funded by the UK Engineering and Physical Sciences Research Council (EPSRC).
For more information please contact Prof. Gerald Buller
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