Terahertz spectroscopy uses beams of electromagnetic radiation that lie between microwaves (used in kitchen ovens) and infrared rays (used in TV remotes) on the spectrum. These waves are known for their ability to examine materials without damaging them, unlike X-rays and ultraviolet light, and are commonly used in other areas like biomedical imaging and pharmaceuticals.

While using this technology to examine a painting, Bianca Jackson, a postdoctoral research fellow at the University of Rochester, found evidence of another painting underneath.

“We were amazed, and we were delighted,” she said during a presentation to the American Chemical Society. “We could not believe our eyes as the image materialized on the screen. Underneath the top painting of the folds of a man’s tunic, we saw an eye, a nose and then a mouth appear. We were seeing what likely was part of an ancient Roman fresco, thousands of years old.”

The ‘he” referred to is Giampetro Campana, a 19th century Italian art collector who assembled an impressive collection of Greek, Roman, and early Italian artwork. Back then, it was common practice for artists to paint over existing works of art, either because they could not afford new canvases or because patrons commissioned new artwork to cover up older or unsuccessful pieces. Researchers had reason to believe that Campana commissioned Trois hommes armes de lances to go over another image.

Initially, the team tried using x-ray radiography  and x-ray fluorescence to find out what secrets lurked beneath. However, it wasn’t until they tried terahertz spectroscopy that the original artwork peeked through.

“No previous imaging technique, including almost half a dozen commonly used to detect hidden images below paintings, forged signatures of artists and other information not visible on the surface has revealed a lost image in this fresco,” Jackson said. “This opens to door to wider use of the technology in the world of art, and we also used the method to study a Russian religious icon and the walls of a mud hut in one of humanity’s first settlements in what was ancient Turkey.”

Photo Credit: J. Bianca Jackson, Ph.D. and Dominique Martos-Levif

July 9-10, 2013
San Francisco, CA

Tickets On Sale Now

A lamp for $5 that does not require any electrical power source?

It may sound like an impossible dream, but two designers in London have built functioning prototypes of GravityLight, a cheap way for people in developing countries t0 light homes, recharge batteries, or power a radio. And they just exceeded their Indiegogo fundraising goal by more than 500 percent with 21 days left in their campaign, so they’ll have the resources to mass-produce the light for less than $5 a unit.

Source: GravityLight

The GravityLIght comes in the bag that will be filled with dirt or stones to power it

Martin Riddiford and Jim Reeves have spent four years developing GravityLight, which uses the Earth’s gravity to generate enough power to light an LED bulb for half an hour — no electrical grid, batteries, or any external generator required.

Using the GravityLight simply requires removing the small white lamp from its bag, hanging it up, filling the bag with about 20 pounds of dirt or rocks, and attaching the bag to bottom of the device.

Gravity powers a generator, light fills your room, and every 30 minutes, you hoist the bag back up.

The goal is to provide clean, efficient light for the 1.5 billion human beings on this planet who still do not have reliable access to electricity and use kerosene-powered lamps. According to Riddiford and Reeves, the use of kerosene results in vastly higher cancer rates due to smoke inhalation, and 2.5 million burn victims due to dropped or jostled lamps every year in India alone. Not to mention the cost: 10 percent to 20 percent of a household’s income in the developing world can go to fuel for lighting.

The initial run of 1,000 GravityLights will be distributed for free to villagers in Africa and India, the designers say. Based on the results, they will tweak the product and then seek NGO and non-profit organizations’ help in distributing it even more widely.

Here’s their explanatory video:

Thousands of backers have contributed anywhere from $10, which gets a thank-you, to $100, which pays for three GravityLights to be sent to needy villages in developing nations, a GravityLight of your own, and several other perks. And four sponsors have signed up at the $5,000 level to help the project succeed — and get their names and logos on the initial run of devices.

Image credits: GravityLight Project

The company manufactures more than a dozen kinds of LED lights, some of which can generate up to 81 lumens — a measurement of visible light — per watt of electricity consumed for each foot of lighting the company installs. A typical incandescent bulb only generates around 14.6 lumens per watt. Philips’ LED light that won the U.S. Department of Energy’s $10 million L Prize generated around 90 lumens per watt of electricity consumed.

LED lighting is still much too expensive for typical consumers based on cost-per-lumen production, Lux Research analyst Murray McCutcheon told VentureBeat. LED lighting cost around $18 per kilolumen produced, while incandescent bulbs are around $2.20 per kilolumen. LED lighting bulbs probably won’t reach that point until 2015, he said.

“LED lighting is poised to make major inroads in the commercial  sector by 2015,” McCutcheon said. “Although not cost-competitive for most applications today, companies like Lumenpulse are finding traction in higher-value applications like showcase projects and external façade lighting that exploit LEDs’ color range and controllability.”

LED lighting providers should capture around 30 percent of the commercial lighting market by 2015. But LED lighting won’t even crack the residential markets until around 2020, when it will have an opportunity to capture around 40 percent of the market, McCutcheon said.

Lumenpulse did not disclose which investors are participating in the first round of funding. Part of the funding includes a credit line from Silicon Valley Bank, the company said. The Boston, Mass.-based company was founded in 2006.

The LED bulb can generate around 900 lumens — a measure of the amount of visible light emitted by a bulb — while consuming around 10 watts of electricity. Typical incandescent bulbs generate around 15 lumens per watt of electricity consumed, while this one generates around 90 lumens per watt of electricity consumed. The Philips bulb also has a lifetime of around 25,000 hours, compared to between 1,000 and 3,000 hours with incandescent bulbs, according to the Department of Energy.

“Winning the L Prize is a welcome dose of positive news for Philips, which has seen its share price fall by nearly a third since January,” Lux Research analyst Murray McCutcheon told VentureBeat. “However, it will likely not be enough to stem the bleeding in its lighting division, which announced weak second-quarter earnings (EBITA) down 60% from a year ago.”

LED lighting is still much too expensive for typical consumers based on cost-per-lumen production, McCutcheon said. LED lighting cost around $18 per kilolumen produced, while incandescent bulbs were around $2.20 per kilolumen. LED lighting bulbs probably won’t reach that point until 2015, he said.

That means the new bulb, which could hit markets as early as next year according to the U.S. Department of Energy, will likely cost a little less than $18 at current market prices. That might be appealing to commercial and government lighting, which require less short-term returns on investments, but it could put off typical consumers looking at lighting options for their homes.

“Philips’ troubles are despite a robustly growing market for LED lighting, and are due in part to the rising tide of more nimble, lower-cost rivals such as Sanan Optoelectronics, China’s largest LED manufacturer, and Samsung,” McCutcheon said.

The bulb produces 152 lumens — a measure of the visible light emitted by a bulb — per watt of electricity consumed, while a typical incandescent bulb only generates around 14.6 lumens per watt. The new bulb, producing around 1,300 lumens using Cree’s new “TrueWhite” technology, exceeds the performance goals set by the U.S. Department of Energy’s L Prize competition.

Should the new bulbs make it to the larger market, they could reduce energy usage in the United States by 16.5 percent, the company said. But that’s a bold claim, given the very high price tags that most LED light bulbs carry. Cree did not indicate how much the new light bulb would cost.

In general, LED lighting is still much too expensive for typical consumers based on cost-per-lumen production, Lux Research analyst Murray McCutcheon told VentureBeat. LED lighting cost around $18 per kilolumen produced, while incandescent bulbs were around $2.20 per kilolumen. LED lighting bulbs probably won’t reach that point until 2015, he said.

“LEDs will gain their first traction in the government and some commercial buildings, because of the longer return on investment and payback horizons,” McCutcheon said. “However we see no in-roads into the residential market until 2020 because the payback period residential consumers demand is 2 years.”

LED lighting providers like Cree should capture around 30 percent of the commercial lighting market by 2015. But LED lighting won’t even crack the residential markets until around 2020, when it will have an opportunity to capture around 40 percent of the market, McCutcheon said.