If you need assistance, please send an email to forum at 4hv dot org. To ensure your email is not marked as spam, please include the phrase "4hv help" in the subject line. You can also find assistance via IRC, at irc.shadowworld.net, room #hvcomm.
Support 4hv.org!
Donate:
4hv.org is hosted on a dedicated server. Unfortunately, this server costs and we rely on the help of site members to keep 4hv.org running. Please consider donating. We will place your name on the thanks list and you'll be helping to keep 4hv.org alive and free for everyone. Members whose names appear in red bold have donated recently. Green bold denotes those who have recently donated to keep the server carbon neutral.
Special Thanks To:
Aaron Holmes
Aaron Wheeler
Adam Horden
Alan Scrimgeour
Andre
Andrew Haynes
Anonymous000
asabase
Austin Weil
barney
Barry
Bert Hickman
Bill Kukowski
Blitzorn
Brandon Paradelas
Bruce Bowling
BubeeMike
Byong Park
Cesiumsponge
Chris F.
Chris Hooper
Corey Worthington
Derek Woodroffe
Dalus
Dan Strother
Daniel Davis
Daniel Uhrenholt
datasheetarchive
Dave Billington
Dave Marshall
David F.
Dennis Rogers
drelectrix
Dr. John Gudenas
Dr. Spark
E.TexasTesla
eastvoltresearch
Eirik Taylor
Erik Dyakov
Erlend^SE
Finn Hammer
Firebug24k
GalliumMan
Gary Peterson
George Slade
GhostNull
Gordon Mcknight
Graham Armitage
Grant
GreySoul
Henry H
IamSmooth
In memory of Leo Powning
Jacob Cash
James Howells
James Pawson
Jeff Greenfield
Jeff Thomas
Jesse Frost
Jim Mitchell
jlr134
Joe Mastroianni
John Forcina
John Oberg
John Willcutt
Jon Newcomb
klugesmith
Leslie Wright
Lutz Hoffman
Mads Barnkob
Martin King
Mats Karlsson
Matt Gibson
Matthew Guidry
mbd
Michael D'Angelo
Mikkel
mileswaldron
mister_rf
Neil Foster
Nick de Smith
Nick Soroka
nicklenorp
Nik
Norman Stanley
Patrick Coleman
Paul Brodie
Paul Jordan
Paul Montgomery
Ped
Peter Krogen
Peter Terren
PhilGood
Richard Feldman
Robert Bush
Royce Bailey
Scott Fusare
Scott Newman
smiffy
Stella
Steven Busic
Steve Conner
Steve Jones
Steve Ward
Sulaiman
Thomas Coyle
Thomas A. Wallace
Thomas W
Timo
Torch
Ulf Jonsson
vasil
Vaxian
vladi mazzilli
wastehl
Weston
William Kim
William N.
William Stehl
Wesley Venis
The aforementioned have contributed financially to the continuing triumph of 4hv.org. They are deserving of my most heartfelt thanks.
Registered Member #1667
Joined: Sat Aug 30 2008, 09:57PM
Location:
Posts: 374
There's an interesting article about phased arrays . The idea is to create a light field that is controlled in both amplitude and phase at every point of the emitting surface.
beam steering: When all "pixels" emit with the same amplitude and uniform phase, a plane wave is emitted. Linearly varying phase values along one direction of the chip are equivalent to a plane wave emerging under a defined angle with respect to the chip normal (think stacked iso-planes intersecting the chip plane under an odd angle, the intersection lines marking periods of the in-plane phase). Thus, any point in the far field can be addressed by dialing in the appropriate phases.
holography: Imagine viewing a solid object inside a cardboard box. All the emerging light rays must pass the open surface of the box. Once it will be possible to reproduce the light field at this surface with a holographic display, the inside will look exactly the same from any point outside the box. However, that's a hell lot of information to be processed. A suitable approximation is to use head tracking to reject all light rays outside the solid angle that acutally arrives at the observer(s). Yes, this product exists.
Unfortunately, the phased arrays mentioned at the beginning are still passive, meaning that they just show a fixed pattern of light. Mashing them up with modulators would enable us to build holographic displays.
Other interesting approaches include writing holographic patterns like frames of a movie and full-color holographic displays based on LCD display technology and laser illumination.
Registered Member #2901
Joined: Thu Jun 03 2010, 01:25PM
Location:
Posts: 837
Holographic displays have already been build with OASLMs ... hell, beam steering in general has already been done with SLMs.
The method is novel, but not necessarily very useful ... even it's compactness isn't that special, with a sidelit/TIR approach you can light a SLM without needing much room for fanning out the laser source as well.
Registered Member #1667
Joined: Sat Aug 30 2008, 09:57PM
Location:
Posts: 374
I think the compactness is the major feature here and being an integrated fabrication technique, no high-bandwidth interconnects to the millions of modulators needed have to be implemented. We may even see phase array displays on the top side of the necessary image processing circuitry. That is rather neat to begin with.
This site is powered by e107, which is released under the GNU GPL License. All work on this site, except where otherwise noted, is licensed under a Creative Commons Attribution-ShareAlike 2.5 License. By submitting any information to this site, you agree that anything submitted will be so licensed. Please read our Disclaimer and Policies page for information on your rights and responsibilities regarding this site.
[news] 2d optical phased arrays created
