Nav: Home

The perfect terahertz beam -- thanks to the 3D printer

July 11, 2018

Terahertz radiation can be used for a wide variety of applications and is used today for airport security checks just as much as it is for material analysis in the lab. The wavelength of this radiation is in the millimetre range, meaning that it is significantly larger than the wavelength of visible light. It also requires specialised techniques to manipulate the beams and get them into the right shape. At TU Wien, shaping terahertz beams is now something of a resounding success: with the help of a precisely calculated plastic screen produced on the 3D printer, terahertz beams can be shaped as desired.

Like lenses - only better

"Normal plastic is transparent for terahertz beams, in a similar way as glass is for visible light," explains Prof. Andrei Pimenov from the Institute of Solid State Physics at TU Wien. "However, terahertz waves slow down a little when they pass through plastic. This means that the crests and troughs of the beam become a little displaced - we call that phase shifting."

This phase shifting can be used to shape a beam. Exactly the same thing happens - in a much simpler form - with an optical lens made of glass: when the lens is thicker in the middle than on the edge, a light beam in the middle spends more time in the glass than another beam that simultaneously hits the edge of the lens. The light beams in the middle are therefore more phase delayed than the light beams on the edge. This is exactly what causes the shape of the beam to change; a wider beam of light can be focussed on a single point.

And yet the possibilities are still far from being exhausted. "We didn't just want to map a wide beam to a point. Our goal was to be able to bring any beam into any shape," says Jan Gosporadic, a PhD student in Andrei Pimenov's team.

The screen from the 3D printer

This is achieved by inserting a precisely adapted plastic screen into the beam. The screen has a diameter of just a few centimetres, its thickness varying from 0 to 4 mm. The thickness of the screen must be adjusted step by step so that the different areas of the beam are deflected in a controlled way, resulting in the desired image at the end. A special calculation method has been developed in order to obtain the desired screen design. From this we can then produce the matching screen from an ordinary 3D printer.

"The process is amazingly simple," says Andrei Pimenov. "You don't even need a 3D printer with an especially high resolution. If the precision of the structure is significantly better than the wavelength of the radiation used, then it's enough - this is no problem for terahertz radiation with a 2mm wavelength."

In order to highlight the possibilities offered by the technique, the team have produced different screens, including one which brings a wide beam into the shape of the TU Wien logo. "This shows that there are hardly any geometric limits to the technology," says Andrei Pimenov. "Our method is relatively easy to apply, which leads us to believe that the technology will be rapidly introduced for use in many areas and that the terahertz technology that is currently emerging will make it a bit more precise and versatile."
-end-
Contact:

Prof. Andrei Pimenov
Institute for Solid State Physics
TU Wien
Wiedner Hauptstraße 8-10, 1040 Wien
T: +43-1-58801-137 23
andrei.pimenov(at)ifp.tuwien.ac.at

Vienna University of Technology

Related Radiation Articles:

Cloudy with a chance of radiation: NASA studies simulated radiation
NASA's Human Research Program (HRP) is simulating space radiation on Earth following upgrades to the NASA Space Radiation Laboratory (NSRL) at the US Department of Energy's Brookhaven National Laboratory.
Visualizing nuclear radiation
Extraordinary decontamination efforts are underway in areas affected by the 2011 nuclear accidents in Japan.
Measuring radiation damage on the fly
Researchers at MIT and elsewhere have found a new way to measure radiation damage in materials, quickly, cheaply and continuously, using transient grating spectroscopy.
Radiation that knocks electrons out and down, one after another
Researchers at Japan's Tohoku University are investigating novel ways by which electrons are knocked out of matter.
Novel advancements in radiation tolerance of HEMTs
When it comes to putting technology in space, size and mass are prime considerations.
Radiation-guided nanoparticles zero in on metastatic cancer
Zap a tumor with radiation to trigger expression of a molecule, then attack that molecule with a drug-loaded nanoparticle.
Graphene is both transparent and opaque to radiation
A microchip that filters out unwanted radiation with the help of graphene has been developed by scientists from the EPFL and tested by researchers of the University of Geneva (UNIGE).
Radiation causes blindness in wild animals in Chernobyl
This year marks 30 years since the Chernobyl nuclear accident.
No proof that radiation from X rays and CT scans causes cancer
The widespread belief that radiation from X rays, CT scans and other medical imaging can cause cancer is based on an unproven, decades-old theoretical model, according to a study published in the American Journal of Clinical Oncology.
Some radiation okay for expectant mother and fetus
During pregnancy, approximately 5 to 8 percent of women sustain traumatic injuries, including fractures and muscle tears.

Related Radiation Reading:

Radiation: What It Is, What You Need to Know
by Robert Peter Gale (Author), Eric Lax (Author)

Radiation Oncology: A Question-Based Review
by Borislav Hristov (Author), Steven H Lin MD PhD (Author), John P. Christodouleas MD MPH (Author)

Strange Glow: The Story of Radiation
by Timothy J. Jorgensen (Author)

Radiation Nation: Fallout of Modern Technology - Your Complete Guide to EMF Protection & Safety: The Proven Health Risks of Electromagnetic Radiation (EMF) & What to Do Protect Yourself & Family
by Daniel T. DeBaun (Author), Ryan DeBaun (Author), Dave Asprey (Foreword)

Strategies for Radiation Therapy Treatment Planning
by Ping Xia PhD (Editor), Andrew Godley PhD (Editor), Chirag Shah MD (Editor), Gregory Videtic MD CM FRCPC (Editor), John Suh MD (Editor)

Perez & Brady's Principles and Practice of Radiation Oncology
by Dr. Edward C. Halperin MD (Author), Dr. David E. Wazer MD (Author), Dr. Carlos A. Perez MD (Author), Dr. Luther W. Brady MD (Author)

Radiation Detection and Measurement
by Glenn F. Knoll (Author)

Essentials of Clinical Radiation Oncology
by Matthew C. Ward MD (Editor), Rahul D. Tendulkar MD (Editor), Gregory Videtic MD CM FRCPC (Editor)

Principles and Practice of Radiation Therapy
by Charles M. Washington MBA RT(T) FASRT (Author), Dennis T. Leaver MS RT(R)(T) FASRT (Author)

Radiation Protection in Medical Radiography
by Mary Alice Statkiewicz Sherer AS RT(R) FASRT (Author), Paula J. Visconti PhD DABR (Author), E. Russell Ritenour PhD DABR FAAPM FACR (Author), Kelli Haynes MSRS RT(R) (Author)

Best Science Podcasts 2018

We have hand picked the best science podcasts for 2018. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Where Joy Hides
When we focus so much on achievement and success, it's easy to lose sight of joy. This hour, TED speakers search for joy in unexpected places, and explain why it's crucial to a fulfilling life. Speakers include inventor Simone Giertz, designer Ingrid Fetell Lee, journalist David Baron, and musician Meklit Hadero.
Now Playing: Science for the People

#499 Technology, Work and The Future (Rebroadcast)
This week, we're thinking about how rapidly advancing technology will change our future, our work, and our well-being. We speak to Richard and Daniel Susskind about their book "The Future of Professions: How Technology Will Transform the Work of Human Experts" about the impacts technology may have on professional work. And Nicholas Agar comes on to talk about his book "The Sceptical Optimist" and the ways new technologies will affect our perceptions and well-being.