Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Novel zoom objective with deformable mirrors

18.01.2010
Unmanned aerial vehicles UAVs deployed on landscape analysis missions carry optical measuring equipment that is required to operate free of chromatic aberration. Researchers have now designed an all-reflective zoom objective with deformable mirrors.

An small unmanned aerial vehicle (UAV) circles above the ground, capturing the typical green of a coniferous forest or the radiated heat from a town. The objectives in its on-board measuring equipment must function free of chromatic aberration across a wide spectral range – from the ultraviolet region through the visible band and right up to the near and medium infrared range.

In such a scenario, conventional lens systems comprised of several lens elements are of limited use: when required to image a wide spectral range, the image quality drops – the image suffers from color fringing and becomes blurred. Traditionally, specific lenses have been used for each different spectral band. However, the difficulty is that UAVs can only carry a limited amount of weight.

Researchers from the Fraunhofer Institute for Photonic Microsystems IPMS are currently working to make it possible to capture images free from chromatic aberration in a number of spectral ranges using a single system. This would have the advantage of prolonging the battery’s life and increasing the aircraft’s endurance. Group manager Dr. Heinrich Grüger of the IPMS says: “We’ve come up with a design for a new objective in which we’ve used mirrors instead of standard lens elements.” The objective is comprised of four mirrors, carefully arranged to avoid obscuration – this produces a higher-contrast image. Two deformable mirrors take care of the triple zoom range – with no loss of image quality. The new design eliminates the need for elaborate mechanical guides within the lens barrel.

Grüger believes the new objective is potentially highly marketable: “Both the automation technology sector and the automobile and equipment engineering sector would profit from this type of objective.” Suitable deformable mirrors will have to be created – conventional optical mirrors are rigid. Grüger says: “For the zoom function, we need mirrors that will permit flexible actuator control of the radius of curvature.”

Although IPMS scientists have already developed deformable mirrors, they have not yet managed to achieve the size and degree of variability required for the mirror zoom objective. Optical simulations have shown that the mirrors would need to be at least 12 millimeters in diameter in order to produce a zoom objective with a sufficient f-number. Nevertheless, the researchers have already been able to demonstrate the optical performance of the objective: they built three identical setups with three different focal lengths in which the deformable mirrors were replaced by conventional rigid mirrors.

Kristof Seidl | Fraunhofer Gesellschaft
Further information:
http://www.fraunhofer.de
http://www.fraunhofer.de/en/press/research-news/2010/january/objective-deformable-mirrors.jsp

More articles from Physics and Astronomy:

nachricht Enhancing the quantum sensing capabilities of diamond
23.11.2017 | The Hebrew University of Jerusalem

nachricht Quantum optics allows us to abandon expensive lasers in spectroscopy
22.11.2017 | Lomonosov Moscow State University

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Frictional Heat Powers Hydrothermal Activity on Enceladus

Computer simulation shows how the icy moon heats water in a porous rock core

Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Underwater acoustic localization of marine mammals and vehicles

23.11.2017 | Information Technology

Enhancing the quantum sensing capabilities of diamond

23.11.2017 | Physics and Astronomy

Meadows beat out shrubs when it comes to storing carbon

23.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>