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




TECH SPACE
Cheap, color, holographic video
by Larry Hardesty for MIT News
Boston MA (SPX) Jun 24, 2013


A hologram of a butterfly, displayed on both a conventional, monochromatic holographic-video monitor (left) and the MIT researchers' new color monitor. Images: Daniel Smalley.

Researchers at MIT's Media Lab have reported, in the journal Nature, a new approach to generating holograms that could lead to color holographic-video displays that are much cheaper to manufacture than today's experimental, monochromatic displays. The same technique could also increase the resolution of conventional 2-D displays.

Using the new technique, Daniel Smalley, a graduate student in the Media Lab and first author on the new paper, is building a prototype color holographic-video display whose resolution is roughly that of a standard-definition TV and which can update video images 30 times a second, fast enough to produce the illusion of motion. The heart of the display is an optical chip, resembling a microscope slide, that Smalley built, using only MIT facilities, for about $10.

"Everything else in there costs more than the chip," says Smalley's thesis advisor, Michael Bove, a principal research scientist at the Media Lab and head of its Object-Based Media Group. "The power supplies in there cost more than the chip. The plastic costs more than the chip."

Joining Bove and Smalley on the Nature paper are two other graduate students in Bove's group, James Barabas and Sundeep Jolly, and Quinn Smithwick, who was a postdoc at MIT at the time but is now a research scientist at Disney Research.

When light strikes an object with an irregular surface, it bounces off at a huge variety of angles, so that different aspects of the object are disclosed when it's viewed from different perspectives. In a hologram, a beam of light passes through a so-called diffraction fringe, which bends the light so that it, too, emerges at a host of different angles.

One way to produce holographic video is to create diffraction fringes from patterns displayed on an otherwise transparent screen. The problem with that approach, Bove explains, is that the pixels of the diffraction pattern have to be as small as the wavelength of the light they're bending, and "most display technologies don't happily shrink down that much."

Sound footing
Stephen Benton, a Media Lab professor who died in 2003, created one of the first holographic-video displays by adopting a different technique, called acousto-optic modulation, in which precisely engineered sound waves are sent through a piece of transparent material. "The waves basically squeeze and stretch the material, and they change its index of refraction," Bove says. "So if you shine a laser through it, [the waves] diffract it."

Benton's most sophisticated display - the Mark-II, which was built with the help of Bove's group - applied acousto-optic modulation to a crystal of an expensive material called tellurium dioxide. "That was the biggest piece of tellurium dioxide crystal that had ever been grown," Bove says. "And that wasn't TV resolution. So there was a definite scaling problem going on there."

Smalley instead uses a much smaller crystal of a material called lithium niobate. Just beneath the surface of the crystal he creates microscopic channels known as waveguides, which confine the light traveling through them. Onto each waveguide, he also deposits a metal electrode, which can produce an acoustic wave.

Each waveguide corresponds to one row of pixels in the final image. In the Mark-II, the tellurium dioxide crystal had to be big enough that the acoustic waves producing the separate lines of the hologram were insulated from each other. In Smalley's chip, on the other hand, the waveguides with their individual electrodes can be packed mere micrometers apart from each other.

Beams of red, green and blue light are sent down each waveguide, and the frequencies of the acoustic wave passing through the crystal determine which colors pass through and which are filtered out. Combining, say, red and blue to produce purple doesn't require a separate waveguide for each color; it just requires a different acoustic-wave pattern.

Selling points
Bove considers that the most exciting aspect of the new chip. "Until now, if you wanted to make a light modulator for a video projector, or an LCD panel for a TV, or something like that, you had to deal with the red light, the green light and the blue light separately," he says. "If you look closely at an LCD panel, each pixel actually has three little color filters in it. There's a red subpixel, a green subpixel and a blue subpixel."

"First of all," he continues, "that's inefficient, because the filters, even if they were perfect, would throw away two-thirds of the light. But second, it reduces either the resolution or the speed at which the modulator can operate."

According to Smalley, on the other hand, "What's most exciting about [the new chip] is that it's a waveguide-based platform, which is a major departure from every other type of spatial light modulator used for holographic video right now." Waveguides are already a common feature in commercial optoelectronics, Smalley explains, and techniques for manufacturing them are well established.

"One of the big advantages here is that you get to use all the tools and techniques of integrated optics," he says. "Any problem we're going to meet now in holographic video displays, we can feel confidence that there's a suite of tools to attack it, relatively simply."

.


Related Links
Massachusetts Institute of Technology
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
MakerBot Opens New Manufacturing Factory in Brooklyn
Brooklyn NY (SPX) Jun 17, 2013
MakerBots are made with Brooklyn Pride! With its original roots in the Brooklyn community, MakerBot, the leader in the desktop 3D printing industry, has expanded its manufacturing capability with a new manufacturing facility in the Sunset Park district of Brooklyn. The new facility has 55,000 square feet of production, warehouse and shipping space, and will be home to the manufacturing of ... read more


TECH SPACE
Laser can identify substances, could be military tool

Disney Research creates techniques for high quality, high resolution stereo panoramas

Cheap, color, holographic video

Crowd-funded videogame console selling fast

TECH SPACE
USAF Awards Lockheed Martin Contract for IT and Telecommunications Services

Northrop Grumman Provides Fuel Quantity Indicator For E-3D AWACS

Canada Makes First Call On AEHF

Mutualink Deploys Full Range of Communications Capabilities

TECH SPACE
New Mexico Space Grant Consortium student experiments blast into space from Spaceport America

Arianespace Soyuz Puts Four O3b Networks' Birds Into Orbit

Four O3b Network birds integrated to Arianespace Soyuz launcher

Arianespace will retain its market leadership by building on the company's flexibility and agility

TECH SPACE
Raytheon's latest air traffic management systems go into continuous operation

Raytheon's Satellite Air Navigation System marks 10 years of continuous service in the US

Raytheon unveils Excalibur with dual-mode guidance

Northrop Grumman to Offer Improved GPS-Challenged Navigation and Geo-Registration Solution for USAF

TECH SPACE
Hollande seeks Rafale jet deal with Qatar

Qantas, BA in China prison labour row

First Lockheed Martin F-35C Reports to the Navy

Airbus shows off new military transport plane

TECH SPACE
New TCH Series Offers Hermetically Sealed Tantalum Polymer Chip Capacitors For Aerospace Applications

Danish chemists in molecular chip breakthrough

Graphene-based system could lead to improved information processing

Making memories: Practical quantum computing moves closer to reality

TECH SPACE
Five Years of Stereo Imaging for NASA's TWINS

Vegetation as Seen by Suomi NPP

How did a third radiation belt appear in the Earth's upper atmosphere

Arianespace to launch Gokturk-1 high-resolution observation satellite

TECH SPACE
Indonesia sorry for haze, sends thousands to fight fires

Indonesia steps up firefighting, Malaysia still in smog

Singapore's economy starts to choke on Indonesia smoke

Shipping firms warn of haze danger in Malacca Strait




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