Free Newsletters - Space News - Defense Alert - Environment Report - Energy Monitor
. Space Industry and Business News .




TECH SPACE
New camera system creates high-resolution 3-D images from up to a kilometer away
by Staff Writers
Washington DC (SPX) Apr 09, 2013


This shows 3-D images of a mannequin (top) and person (bottom) from 325 meters away. The left-hand panels show close-up photos of the targets taken with a standard camera. In the center are 3-D images of these targets taken by the scanner from 325 meters away. On the right is a color-coded map showing the number of photons that bounce off the targets and return to the detector, with black indicating a low number of photons. Notice that human skin does not show up well using the scanner: the mannequin's face includes depth information, but the person's face does not. Credit: Optics Express.

A standard camera takes flat, 2-D pictures. To get 3-D information, such as the distance to a far-away object, scientists can bounce a laser beam off the object and measure how long it takes the light to travel back to a detector.

The technique, called time-of-flight (ToF), is already used in machine vision, navigation systems for autonomous vehicles, and other applications, but many current ToF systems have a relatively short range and struggle to image objects that do not reflect laser light well.

A team of Scotland-based physicists has recently tackled these limitations and reported their findings in the Optical Society's (OSA) open-access journal Optics Express.

The research team, led by Gerald Buller, a professor at Heriot-Watt University in Edinburgh, Scotland, describes a ToF imaging system that can gather high-resolution, 3-D information about objects that are typically very difficult to image, from up to a kilometer away.

The new system works by sweeping a low-power infrared laser beam rapidly over an object. It then records, pixel-by-pixel, the round-trip flight time of the photons in the beam as they bounce off the object and arrive back at the source. The system can resolve depth on the millimeter scale over long distances using a detector that can "count" individual photons.

Although other approaches can have exceptional depth resolution, the ability of the new system to image objects like items of clothing that do not easily reflect laser pulses makes it useful in a wider variety of field situations, says Heriot-Watt University Research Fellow Aongus McCarthy, the first author of the Optics Express paper.

"Our approach gives a low-power route to the depth imaging of ordinary, small targets at very long range," McCarthy says. "Whilst it is possible that other depth-ranging techniques will match or out-perform some characteristics of these measurements, this single-photon counting approach gives a unique trade-off between depth resolution, range, data-acquisition time, and laser-power levels."

The primary use of the system is likely to be scanning static, man-made targets, such as vehicles. With some modifications to the image-processing software, it could also determine their speed and direction.

One of the key characteristics of the system is the long wavelength of laser light the researchers chose. The light has a wavelength of 1,560 nanometers, meaning it is longer, or "redder," than visible light, which is only about 380-750 nanometers in wavelength.

This long-wavelength light travels more easily through the atmosphere, is not drowned out by sunlight, and is safe for eyes at low power. Many previous ToF systems could not detect the extra-long wavelengths that the Scottish team's device is specially designed to sense.

The scanner is particularly good at identifying objects hidden behind clutter, such as foliage. However, it cannot render human faces, instead drawing them as dark, featureless areas.

This is because at the long wavelength used by the system, human skin does not reflect back a large enough number of photons to obtain a depth measurement. However, the reflectivity of skin can change under different circumstances.

"Some reports indicate that humans under duress-for example, with perspiring skin-will have significantly greater return signals," and thus should produce better images, McCarthy says.

Outside of target identification, photon-counting depth imaging could be used for a number of scientific purposes, including the remote examination of the health and volume of vegetation and the movement of rock faces, to assess potential hazards. Ultimately, McCarthy says, it could scan and image objects located as far as 10 kilometers away.

"It is clear that the system would have to be miniaturized and ruggedized, but we believe that a lightweight, fully portable scanning depth imager is possible and could be a product in less than five years."

Next steps for the team include making the scanner work faster. Although the data for the high-resolution depth images can be acquired in a matter of seconds, currently it takes about five to six minutes from the onset of scanning until a depth image is created by the system.

Most of that lag, McCarthy says, is due to the relatively slow processing time of the team's available computer resources. "We are working on reducing this time by using a solid-state drive and a higher specification computer, which could reduce the total time to well under a minute. In the longer term, the use of more dedicated processors will further reduce this time."

Paper: "Kilometer-range, high resolution depth imaging via 1560 nm wavelength single-photon detection," A. McCarthy et al., Optics Express, Vol. 21, Issue 7, pp. 8904-8915 (2013).

.


Related Links
The Optical Society
Space Technology News - Applications and Research






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





TECH SPACE
Michigan Tech researcher slashes optics laboratory costs
Houghton MI (SPX) Apr 04, 2013
Just as the power of the open-source design has driven down the cost of software to the point that it is accessible to most people, open-source hardware makes it possible to drive down the cost of doing experimental science and expand access to everyone. As part of this movement, a Michigan Technological University lab has introduced a library of open-source, 3-D-printable optics components in a ... read more


TECH SPACE
What's between a slip and a slide?

Light may recast copper as chemical industry 'holy grail'

New camera system creates high-resolution 3-D images from up to a kilometer away

Theory and practice key to optimized broadband, low-loss optical metamaterials

TECH SPACE
Northrop Grumman Awarded U.S. Navy Contract to Upgrade, Enhance NGC2P Tactical Data Link Processor

Soldiers and Families Can Suffer Negative Effects from Modern Communication Technologies

DARPA Seeks More Robust Military Wireless Networks

DoD Selects Northrop Grumman for Joint Command and Control System

TECH SPACE
Future Looks Bright for Private US Space Ventures

Europe's next ATV resupply spacecraft enters final preparatio?ns for its Ariane 5 launch

ILS Proton Launches Satmex 8 Satellite for Satmex

When quality counts: Arianespace reaffirms its North American market presence

TECH SPACE
China preps civilian use of GPS system

GPS device could stem bike thefts

Apple patent shows pen with GPS, phone

Ground system improves satellite navigation precision

TECH SPACE
Fasten seatbelts for bumpier flights: climate study

Hong Kong airbridge collapse rips off plane door

Third F-35B For United Kingdom Makes First Flight

Eurocopter vies for big-ticket Polish chopper deal

TECH SPACE
World Record Silicon-based Millimeter-wave Power Amplifiers

A giant step toward miniaturization

ORNL microscopy uncovers "dancing" silicon atoms in graphene

A mighty wind

TECH SPACE
First Light for ISERV Pathfinder, Space Station's Newest 'Eye' on Earth

Watching over you

New Live Bi-ocular Animations of Two Oceans Now Available

NASA Flies Radar South on Wide-Ranging Scientific Expedition

TECH SPACE
Albania to hold referendum on waste imports

Smog-eating pavement on greenest street in America

Latin America looks to earn from e-waste

Russia seeks Baltic pollution partnerships




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement