Featured Research

from universities, journals, and other organizations

X-rays Shine Light On High-intensity Gas Lamps

Date:
April 26, 2005
Source:
National Institute of Standards and Technology
Summary:
An X-ray technique developed by physicists at the National Institute of Standards and Technology (NIST) is helping to improve the design and energy efficiency of the bright white lights often used to illuminate stadiums, roads and many other settings.

Scientists perform a series of calculations to transform X-ray intensity data (left, a montage of five separate images) into an image of the spatial distribution of mercury atoms in a high-intensity discharge lamp (right). Blue indicates the lowest density of atoms, red the highest.
Credit: Image courtesy of National Institute of Standards and Technology

An X-ray technique developed by physicists at the National Institute of Standards and Technology (NIST) is helping to improve the design and energy efficiency of the bright white lights often used to illuminate stadiums, roads and many other settings.

High-intensity gas discharge (HID) lamps produce 26 percent of the nation's light output, but, as a result of their high energy efficiency, consume only 17 percent of the electricity used for lighting. Continuing improvements in energy efficiency and other features will reduce electricity use and the negative environmental effects of power generation. Improved efficiency could save lots of money: HID lamps consume roughly 4 percent of U.S. electricity, equivalent to about $10 billion annually.

The NIST technique uses X-ray imaging to improve understanding of the complex science underlying the HID lamp's design. Such lamps have two electrodes in a ceramic tube that contains small amounts of mercury and metal-halide salts. An electric current between the electrodes heats the lamp, vaporizing the mercury and metal-halide salts and producing a gas of electrically charged particles, or plasma. Metal atoms, excited by collisions with electrons in the plasma, emit light at many different wavelengths, producing a bright, white light.

In the NIST technique, an HID lamp is placed in an intense beam of X-rays. The X-rays penetrate the lamp's ceramic housing but are partially absorbed by the mercury gas in the lamp, casting a shadow in the beam. A special digital camera behind the lamp captures a high-resolution, two-dimensional image of this X-ray shadow showing the density of mercury atoms in the discharge. From the mercury distribution, the temperature distribution in the lamp also can be determined. This technique has been used to quantify processes that consume power without producing light.

Researchers now are demonstrating that this technique can be implemented in industrial laboratories using small-scale X-ray sources. This project provides measurement support to universities participating in the Advanced Light Source Research Program-II (ALITE-II) of the Electric Power Research Institute. The goals of the consortium are to make significant improvements in lighting technology by combining the resources of university, industry and government laboratories in pre-competitive research.

###

*J.J. Curry and C.J. Sansonetti. X-Ray Absorption Imaging of High-Pressure Lighting Plasmas. IEEE Transactions on Plasma Science, April 2005


Story Source:

The above story is based on materials provided by National Institute of Standards and Technology. Note: Materials may be edited for content and length.


Cite This Page:

National Institute of Standards and Technology. "X-rays Shine Light On High-intensity Gas Lamps." ScienceDaily. ScienceDaily, 26 April 2005. <www.sciencedaily.com/releases/2005/04/050421210927.htm>.
National Institute of Standards and Technology. (2005, April 26). X-rays Shine Light On High-intensity Gas Lamps. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2005/04/050421210927.htm
National Institute of Standards and Technology. "X-rays Shine Light On High-intensity Gas Lamps." ScienceDaily. www.sciencedaily.com/releases/2005/04/050421210927.htm (accessed July 24, 2014).

Share This




More Matter & Energy News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

TSA Administrator on Politics and Flight Bans

TSA Administrator on Politics and Flight Bans

AP (July 24, 2014) TSA administrator, John Pistole's took part in the Aspen Security Forum 2014, where he answered questions on lifting of the ban on flights into Israel's Tel Aviv airport and whether politics played a role in lifting the ban. (July 24) Video provided by AP
Powered by NewsLook.com
Creative Makeovers for Ugly Cellphone Towers

Creative Makeovers for Ugly Cellphone Towers

AP (July 24, 2014) Mobile phone companies and communities across the country are going to new lengths to disguise those unsightly cellphone towers. From a church bell tower to a flagpole, even a pencil, some towers are trying to make a point. (July 24) Video provided by AP
Powered by NewsLook.com
Algonquin Power Goes Activist on Its Target Gas Natural

Algonquin Power Goes Activist on Its Target Gas Natural

TheStreet (July 23, 2014) When The Deal's Amanda Levin exclusively reported that Gas Natural had been talking to potential suitors, the Ohio company responded with a flat denial, claiming its board had not talked to anyone about a possible sale. Lo and behold, Canadian utility Algonquin Power and Utilities not only had approached the company, but it did it three times. Its last offer was for $13 per share as Gas Natural's was trading at a 60-day moving average of about $12.50 per share. Now Algonquin, which has a 4.9% stake in Gas Natural, has taken its case to shareholders, calling on them to back its proposals or, possibly, a change in the target's board. Video provided by TheStreet
Powered by NewsLook.com
Robot Parking Valet Creates Stress-Free Travel

Robot Parking Valet Creates Stress-Free Travel

AP (July 23, 2014) 'Ray' the robotic parking valet at Dusseldorf Airport in Germany lets travelers to avoid the hassle of finding a parking spot before heading to the check-in desk. (July 23) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

    Health News

      Environment News

        Technology News



          Save/Print:
          Share:

          Free Subscriptions


          Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

          Get Social & Mobile


          Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

          Have Feedback?


          Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
          Mobile: iPhone Android Web
          Follow: Facebook Twitter Google+
          Subscribe: RSS Feeds Email Newsletters
          Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins