Metamaterial laser filters for aviation LamdaGuard Ltd
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Transcript of Metamaterial laser filters for aviation LamdaGuard Ltd
2008
Risks & Hazards
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Courtesy: www.laserpointersafety.com
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Forecast
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2007 2008 2009 2010 2011 2012 2013 2014 2015
Rep
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ents
UK
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EU
World
Beam flashes: It is hard to hand-hold a
laser on a moving target that is far away.
That's why in most laser pointer incidents,
pilots don't see a steady light on them.
Instead, they see one or more flashes.
The flashes are distracting at best, and at
worse, they can be bright enough to
cause temporary flashblindness.
Example: This is similar to having a camera
flash (or flashes) go off in your face
Beam size: A laser's beam spreads out. At
long ranges the beam can be many inches or
even feet in diameter. When laser light hits an
aircraft's windscreen, tiny scratches and dirt
spread the light out even more, causing glare
around the beam center. The result is that
pilots do not see a small dot, they see a
large glow similar to being in a flashlight or
searchlight beam. It can be difficult or
impossible to see through the glow.
Courtesy: www.laserpointersafety.com
Eye injury: Though it is unlikely, high power
visible or invisible (infrared, ultraviolet)
laser light could cause permanent eye
injury. The injury could be relatively minor,
such as spots only detectable by medical exam
or on the periphery of vision.
Pilots are not expecting bright lights during
landings, their eyes are exposed to potential
illuminations by powerful laser beams.
Courtesy: www.laserpointersafety.com
Visual Hazard Distances for 532nm (green) pointer lasers
Laser Power
Power
Increase
(compared
to 5mW)
Sqrt of
power
increase
Max eye
hazard
distance
Max flash
blindness
hazard
distance
Max glare/
disruption
hazard
distance
Max
distraction
hazard
distance
5 mW x1 1.0 16 m 80 m 366 m 3560 m
50 mW x10 3.2 50 m 250 m 1156 m 11276 m
125 mW x25 5.0 79 m 396 m 1829 m 17830 m
250 mW x50 7.1 112 m 560 m 2586 m 25216 m
500 mW x100 10 160 m 800 m 3660 m 35600 m
1000 mW (1W) x200 14.1 320 m 1600 m 7320 m 71200 m
Distraction Glare/Disruption Flash blindness
Patrick Murphy, Lasers & Aviation Safety, International Laser Display Allocation, Sep 2010
A solution needs to attenuate power ~20 times
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Array of 24 Blue Lasers
Courtesy: frigginSmift via youtube.com
FACT: It is likely that many pilots would go
through their entire career without ever
encountering laser interference so wearing
goggles against lasers is a less attractive
solution
FACT: Laser protective
goggles and glasses must be
on before exposure to the
laser. They operate at a
broad spectrum not at the
laser wavelengths only
Pendry, Metamaterial Congress 2008; www.news.iastate.edu; http://www.metaphotonics.de
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λ
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λ
λ λ
Positive Index η>0 Negative Index η<0
Concept
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Maier & Atwater, JOURNAL OF APPLIED PHYSICS 98, 011101 2005
Z. Liu et al., Science 315, 5818 (March 23, 2007).
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Microwave
Filter!
1cm
200 nm
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•ε
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Developing an optimal solution:
Metamaterial
Nano-particles
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Cross-section Fields on surface
αε
ε
Nano-particle
Metamaterial Array
Unit cell
100x
zoom
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In-house Computational Capability
www.cst.com
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Fields on surface Cross-section of electric field at resonant
frequency (λ=500 nm)
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ε
200 400 600 800 1000-15
-10
-5
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5
10
15
0 @ 332.9778 nm (900.9611 THz)
Wavelength [nm]
Re()
m
=1.0
m
=1.5
m
=1.7
m
=3.0
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Wavelength [nm]
Im(
)
m
=1.0
m
=1.5
m
=1.7
m
=3.0
600 800 1000 12000
0.2
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0.8
1
Frequency [THz]
Am
plit
ude
S 11
D=10 nm
D=20 nm
600 800 1000 12000
0.2
0.4
0.6
0.8
1
Frequency [THz]
Am
plit
ude
S 21
D=10 nm
D=20 nm
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Kallos et al., PHYSICAL REVIEW B 84, 045102 (2011); Kallos et al., RADIO SCIENCE, VOL. 46, RS0E06
Proposed use in Civil Aviation
Nano-particle
Metamaterial Array
Protective Layer
[Inside cockpit]
Metamaterial
Adhesive layer
Cockpit Glass
[Outside] 10x
zoom Nano-particle
100x
zoom
200 400 600 800 1000-15
-10
-5
0
5
10
15
0 @ 332.9778 nm (900.9611 THz)
Wavelength [nm]
Re()
m
=1.0
m
=1.5
m
=1.7
m
=3.0
200 400 600 800 1000-30
-20
-10
0
10
20
30
Wavelength [nm]
Im(
)
m
=1.0
m
=1.5
m
=1.7
m
=3.0
Laser Lights Blocked:
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First Prototypes in Q1, 2012
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LAMDA GUARD LTD.
London, UK
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Prof. Clive Parini
Director of Antenna &
Electromagnetics Research Group
Prof. Pandurang Ashrit
Director of Thin Films and
Photonics Research Group
Prof. Filipe Chibante
Head of Nano-Composites
Engineering Research Group
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Kallos et al., RADIO SCIENCE, VOL. 46, RS0E06, (2011)
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Kallos et al., PHYSICAL REVIEW A 79, 063825 2009; Zhang et al., PRL 106, 033901 (2011);
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T. Scharf, Polarized Light in Liquid Crystals and Polymers; http://en.wikipedia.org/wiki/Distributed_Bragg_reflector
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T. Scharf, Polarized Light in Liquid Crystals and Polymers; TyrionL (Own work) [Public domain], via Wikimedia Commons
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Hwang et al., nature materials | VOL 4 | MAY 2005
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Polarized Light in Liquid Crystals and Polymers; Ha et al., Nature Materials, vol.7, pp.43-47 (2008)
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http://en.wikipedia.org/wiki/Split-ring_resonator; Shelby, R. A.; Smith D.R.; Shultz S.; Nemat-Nasser S.C. (2001). "Microwave
transmission through a two-dimensional, isotropic, left-handed metamaterial". Applied Physics Letters 78 (4): 489
•λ λ
• λ
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Schematic diagram for light bending metamaterial,
at 1.5 micrometre wavelength. Courtesy of G.
Dolling et al., Opt. Lett. 31, 1800 (2006)
Microwave negative index metamaterial
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