Securing information with noisy light

Northwestern University and BBN Technologies of Cambridge, Mass have demonstrated a technique for encrypting data with a little help from lasers.

The volume and type of sensitive information being transmitted over data networks continues to grow at a remarkable pace," said Prem Kumar, professor of electrical engineering and computer science at Northwestern’s Robert R. McCormick School of Engineering and Applied Science and co-principal investigator on the project.

Continuity Central reports:

The combined QKD/AlphaEta system has been demonstrated in a nine km link between BBN headquarters and Harvard University in Cambridge, Mass. The AlphaEta encrypted signal carried OC-3 (155Mb/s) SONET data between the two nodes. A fresh encryption key of about 1 kilobit was repetitively loaded every three seconds. In a separate test, the AlphaEta encrypted signal was looped back multiple times to create an effective 36 km link where more than 300 consecutive key exchanges were demonstrated.

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Following that speeder too closely?

Not only do you have to worry about getting tagged with a laser while speeding but now you might just get a ticket for following too closely if you’re using someone in front of you as a shield.

The Oregon Mail Tribune reports that they’re testing a new system that will report the speed of a car as well as the distance between it any any car following it.

Dace Cochran, a patrol sergeant with the Jackson County Sheriff’s office writes:

Here’s what the updated lasers will be able to tell us:

  • The speed of the first car.
  • The distance from the laser operator to the first car.
  • The speed of the second car.
  • The distance from the laser operator to the second car.
  • The distance between the two cars (front bumper to front bumper).
  • The time difference between the two cars.

Once this comes to your state, assuming you aren’t in Oregon now, be careful about using other people as ticket shields. Of course, you could always just slow down.

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Laser bomb sniffer

Electronics Weekly reports that Cascade Technologies, based in Stirling Scotland has developed a system capable of detecting explosives in tightly sealed packages, without opening them.

At the lab, we were sent a sample of explosives in a glass phial in an aluminium package, and that package had been through the post, company CEO John Fuller told Electronics Weekly. We could detect the explosives without opening it.

From the company’s web site:

One such technique, known as Intra pulse spectroscopy, uses the laser in pulsed mode to facilitate its use over the wide range of environmental conditions typically associated with industrial monitoring. Pulsing the laser for up to a microsecond at a time causes instantaneous localised heating within the device, which results in a large frequency chirp. This chirp is harnessed to provide a near instantaneous frequency sweep through many spectroscopic features of interest.

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Dolphin sub sunk

Not literally, but budget cuts are taking it out of action.

Why do you care? Because it achieved a few firsts using lasers!

Less than a year after completing a $50 million project to repair and upgrade the San Diego-based research vessel, the Navy will decommission it Sept. 22. It is the country’s last diesel-electric sub… The Dolphin had other notable firsts: sending the first successful submarine-to-aircraft laser communication and the first sub-to-surface e-mail.

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2006 O’Flaherty Irish Music Retreat

It will be held October 27-29, 2006 in Midlothian, Texas, just 30 minutes south of Dallas, at a comfortable camp and conference center there.

There will be classes in fiddle, flute, harp, uilleann pipes, tinwhistle, bodhran, guitar, piano accordion, button accordion, piano, concertina, harp, mandolin, tenor banjo, bouzouki, singing (English and Gaelic), dancing and our staff includes some of the best players in the Irish tradition, including John Carty, Daithi Sproule, Jerry O’Sullivan, Randal Bays, Shannon Heaton, Roger Landes and others. Online registration in now underway.

For more info, please visit the retreat website at

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Using lasers to deliver drugs

Researchers at the Max Planck Society have devised a method for opening up drug capsules inside tumor cells using a laser.

Fig.: Microcapsules in a cell, (a) before, and (b) after being illuminated with a laser. The arrow indicates the laser beam’s focus. The laser opens the capsules, which release their fluorescent content.

The vehicle that the researchers used was a polymer capsule only a few micrometres in diameter. The walls of the capsules were built from a number of layers of charged polymers, alternating positive and negative. In the laboratory, at least, this is an established way of producing transport containers for medicines, cosmetics, or nutrients, which can also pass through cell membranes. André Skirtach and his colleagues equipped the capsules with a kind of "open sesame". But it didn’t require any magic – just nanoparticles made of gold or silver atoms. The scientists mixed together charged metal nanoparticles along with the polymers composing the walls of the vesicle. The tumour cells absorbed the microcapsules and then the scientists aimed an infrared laser at them. Metal nanoparticles are particularly good at absorbing the laser light and transmitting the heat further into their surroundings, heating up the walls. They became so hot that the bonds broke between the polymers and the shell and the capsules eventually opened.

It remains to be seen how they’ll deliver the capsules to the tumor cells while they’re in the body and what kinds of tumors they’ll be able to treat.

It’s also an open question what happens with the metal nanoparticles that remain in the body.

You thought your laser was powerful

The University of Nebraska is set to unveil their Diocles laser with which they’ll study the interaction of light and matter at high field strengths.

It will have the highest combination of peak power and repetition rate of any laser in the U.S., 100 TW at 10 Hz. When focused, it will be capable of directly increasing an electron’s mass relativistically by 20X.

100 TeraWatts at 10x a second. I want one of these. Then I want a basement to put it into.

Using laser speckle to map blood flow reports

Scientists from Canada’s National Research Council Institute for Biodiagnostics in Winnipeg claim to have developed a technique for measuring blood-flow velocity that is significantly cheaper and faster than existing methods.

Laser speckle imaging is used to monitor and map blood flow through the tissue by tracking minute changes in the skin caused by movement of the blood through the vessels underneath.

Having this information is important in determining if a grafted area will heal properly.

Laser speckle is an optical interference effect that’s observed when laser light is incident on a rough surface, such as living tissue. The light and dark "speckles" are caused by constructive and destructive interference of the scattered light. The speckle pattern fluctuates if the illuminated area contains moving particles, like blood cells. Analysing these fluctuations yields information about blood-flow velocity.

O’Flaherty Retreat Fundraiser Sep 22, 2006

There will be a fund raiser for the O’Flaherty Irish Music Retreat at Trinity Hall Pub starting at 6pm and going until the pub closes.

Please mark your calendars and plan to be there to support the retreat!

Bands that have confirmed include Irish Rogues, Spriggin, Jigsaw, Beyond the Pale, and the Trinity Hall Session Players.

Should be wonderful night of Irish music and dancing.

Video clothing

Ok, there aren’t any lasers involved in this article but this is cool anyway.

At IFA 2006 Philips will be showing off garments and furniture featuring their Lumalive technology that allows the objects to show graphics in real-time.

Lumalive fabrics feature flexible arrays of colored light-emitting diodes (LEDs) fully integrated into the fabric – without compromising the softness or flexibility of the cloth. These light emitting textiles make it possible to create materials that can carry dynamic messages, graphics or multicolored surfaces. Fabrics like drapes, cushions or sofa coverings become active when they illuminate in order to enhance the observer’s mood and positively influence his/her behavior.

Although the fabrics can be cleaned, the batteries and electronics can be removed, it’s not clear if that includes throwing them in the washing machine.