Featured Research

from universities, journals, and other organizations

Scanning electron microscopes: Getting rid of bad vibrations

Date:
March 18, 2014
Source:
Fraunhofer-Gesellschaft
Summary:
Scanning electron microscopes are extremely sensitive and even subtle movements going on around them can affect their accuracy. Vibration control tables already exist to dampen these sometimes barely perceptible disturbances. But now a new kind of isolation platform for the first time integrates sensors and actuators into the mount – resulting in a platform that is more cost-effective and compact than its predecessors.

Platform dampens vibrations in all spatial directions.
Credit: Fraunhofer LBF

Scanning electron microscopes are extremely sensitive and even subtle movements going on around them can affect their accuracy. Vibration control tables already exist to dampen these sometimes barely perceptible disturbances. But now a new kind of isolation platform for the first time integrates sensors and actuators into the mount -- resulting in a platform that is more cost-effective and compact than its predecessors. Its designers will be showcasing this new form of isolation at the Hannover Messe from April 7-11.

Whether you're looking at hairy spider legs, the alien-like faces of ants, or the spiky-looking surfaces of pollen -- a scanning electron microscope delivers high-resolution images that are rich in detail. But you can't get perfect images unless you protect the microscope from vibration. If someone walking across the room or an elevator going up and down between nearby floors makes the table shake, you're unlikely to get good results. The simplest way to quell vibrations is to put the microscope on a granite base -- a stone so heavy that it dampens vibrations occurring at high frequencies from two to three Hertz. Placing a microscope on granite will make it far less susceptible to interference, but not necessarily those vibrations occurring at lower frequencies. When scientists wish to protect sensitive measuring devices from interference, they turn to active damping or, more specifically, an isolation platform. Each of the platform's four integrated swivel-mount modules contains a sensor that measures any vibrations in all three directions and an actuator that counterbalances them in three dimensions.

More cost-effective and compact without compromising performance

Researchers at the Fraunhofer Institute for Structural Durability and System Reliability LBF in Darmstadt have now come up with the first vibration control table of its kind to incorporate function-integrated components. "So instead of using non-adjoining sensors and actuators that are built into the table legs, we have integrated these functional elements directly into the platform's mounting modules," says engineer Torsten Bartel from Fraunhofer LBF. This has the advantage of making the vibration control table considerably more streamlined and cheaper to produce. And practical tests have already shown that the system works. The table dampens interfering vibrations just as well as its traditional counterparts. From April 7-11, the scientists will present their prototype at the Hannover Messe .

So how exactly does this table differ from its predecessors? "Conventional vibration control tables have mounts that are fitted with readymade actuators and sensors that work independently of the table itself. What we have done is to combine these functional elements beforehand within the mounts themselves. We don't use complete actuators -- we use a number of interacting components that carry out the same function," explains Bartel. "So instead of having a system of individual elements producing a team effort, as was usual up to now, we have one composite unit." This includes connecting the actuators to the metal springs. Neither the actuator nor the springs could work on their own -- they can only work together to protect the table.

"We can tailor our system to a variety of applications," says Bartel. This includes adaptations according to the size and weight of the equipment used -- the table takes a different design if it is for, say, an electron microscope, than it would if it were meant for a smaller and lighter device. Reconfiguring the tables' geometry is the top priority here and simply making a smaller table is not enough. Changes in geometry affect the rigidity of the various elements. Similarly, the actuators and sensors take on a different design depending on the nature of the device: the larger the mass, the harder the actuators have to work in order to counteract vibrations.


Story Source:

The above story is based on materials provided by Fraunhofer-Gesellschaft. Note: Materials may be edited for content and length.


Cite This Page:

Fraunhofer-Gesellschaft. "Scanning electron microscopes: Getting rid of bad vibrations." ScienceDaily. ScienceDaily, 18 March 2014. <www.sciencedaily.com/releases/2014/03/140318111704.htm>.
Fraunhofer-Gesellschaft. (2014, March 18). Scanning electron microscopes: Getting rid of bad vibrations. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2014/03/140318111704.htm
Fraunhofer-Gesellschaft. "Scanning electron microscopes: Getting rid of bad vibrations." ScienceDaily. www.sciencedaily.com/releases/2014/03/140318111704.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