Thai researchers trying to perfect a new solar cell using nanotechnology ended up
inventing crime–fighting eyeglasses
If you asked the average person on the street how nanotechnology had affected their lives, they
would probably answer you with a shrug and look of bemusement. But although nanotechnology
is not that well recognised among the general public, that doesn't mean people don't know
anything about it at all. The more discerning consumer knows how to differentiate between
products that apply the benefits of nanotechnology and those that don't.
People will often pay more to buy "nano-products", such as nano-shirts with anti-bacteria
properties, nano-cosmetics because of the way it can help the skin to absorb the products through
to the inner layers of skin, and nano-packaging, as it preserves the freshness of food. But the
application of nanotechnology goes way beyond day to day consumables. The cutting edge
technology is now aiding crime scene investigations.
Models exhibit new nanocrystal eyeglasses specially designed for forensic work. Unveiled on
Thursday, it is the latest of a growing list of nano products launched in Thailand.— WEERAWONG
WONGPREEDEE
Researchers from King Mongkut's Institute of Technology Ladkrabang (KMITL) successfully
developed nanocrystal eyeglasses to help forensic investigators trace evidence at crime scenes
that would normally be invisible to the naked eye.
However, the invention of the glasses, although very impressive, was actually an accident.
"We wanted to develop solar cells with nano-crystallised indium oxynitride. But we found that its
wavelengths of light varies greatly, and even matches the wavelengths that are applicable to
detect sperm, blood stains, saliva and lymph left behind at crime scenes," said Jiti Nukaew,
director of KMITL's nanotechnology research centre.
"Another idea popped into my mind. I thought that it could be developed into nanocrystal
eyeglasses for tracing normally invisible evidence," he said. "So I contacted the Central Institute of
Forensic Science to test the special eyeglasses after five months of laboratory tests."
The researchers coated onto glass and plastic lenses with nano-crystallised indium oxynitride to
make the lens capable of filtering varying wavelengths of light. Investigators can use the glasses
to detect all kinds of evidence all at the same time, doing away with the need for different light
sources that investigators currently use at crime scenes. Using a forensic light source is a lengthy
procedure as it must be conducted multiple times with different wavelengths of light to detect
varying bodily fluids. At the moment, forensic teams use a special tool called a forensic light
source.
However, it is a time-consuming procedure since the process must be conducted multiple times
with each different wavelength of projected light and glass appropriate for each type of fluid. For
example, blue light with a wavelength of 450 nanometres (nm) is needed to detect blood and
sperm, while green light at 520 nm and red light at 630 nm will help detectives see saliva and
fingerprints. Somchai Chalermsooksant, chief of the Central Institute of Forensic Science's crime
scene unit, said discovering fluids normally invisible to the naked eye was difficult without the right
equipment to detect them. And he was hopeful the invention would help detectives track down
criminals more effectively by linking them with bodily fluids found at crime scenes. "At the
moment, we are in a trial process [of nanocrystal eyeglasses], but we are pretty satisfied with its
initial results. We will inform the research team to adjust its weaknesses," said Pol Lt-Col Somchai.
"This is a very significant step of using nanotechnology in crime suppression operations. We have
to learn and do more to get the most out of the technology." Although the nanocrystal eyeglasses
are still far from being standard issue, the potential for them being used across the country and
even the world _ maybe even turning up on the hit US television series Crime Scene Investigation
one day _ is huge.
Pol Lt-Col Somchai explained how useful gathering such evidence at a crime scene is. He cited an
example of a forensic team in the restive South which detected a blood stain using the standard
forensic light source device at a bomb scene. The team then managed to decode the DNA from
the blood sample collected at the scene and found that it matched the DNA of a key suspect being
detained by police. Hi-tech devices that facilitate crime scene investigation were very useful with
certain crimes, such as rape cases, which need strong scientific and physical evidence to tie the
culprit to the crime, he said.
After successfully developing the nanocrystal eyeglasses, KMITL's nanotechnology research team
is now turning its attention back to the original objective _ developing a nano-solar cell. "We
expect to finish it within a year. If successful, we can produce a solar cell that is 10 times cheaper
than the current series by using all domestic materials. We will have no need to import silicon
material," said Mr Jiti. Silicon is the main material used in today's solar cell production, but
Thailand doesn't have the capabilities to produce the man-made material, so the team is looking
into using plastic to produce solar cells, reducing the cost.The scientists believe that the nanosolar cell will also have a greater capacity to absorb solar power than the current silicon cells,
thanks to the special properties of the nano-crystallised indium oxynitride.
But beyond the glasses and solar power, the scientists say there are many more possible
applications for nano-crystallised indium oxynitride, including in medicine. The scientists are
confident this technology is going to help Thailand continue to compete with the world on
innovation and progress.
Bangkok Post : Monday October 29, 2007
Update : 29-10-2007