Metamaterial laser filters for aviation LamdaGuard Ltd

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Transcript of Metamaterial laser filters for aviation LamdaGuard Ltd

2008

Risks & Hazards

Courtesy: www.laserpointersafety.com

Forecast

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2007 2008 2009 2010 2011 2012 2013 2014 2015

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ed In

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UK

US

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

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

• •

λ

λ

λ λ

Positive Index η>0 Negative Index η<0

Concept

Maier & Atwater, JOURNAL OF APPLIED PHYSICS 98, 011101 2005

Z. Liu et al., Science 315, 5818 (March 23, 2007).

Microwave

Filter!

1cm

200 nm

•ε

Developing an optimal solution:

Metamaterial

Nano-particles

Cross-section Fields on surface

αε

ε

Nano-particle

Metamaterial Array

Unit cell

100x

zoom

In-house Computational Capability

www.cst.com

Fields on surface Cross-section of electric field at resonant

frequency (λ=500 nm)

ε

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

600 800 1000 12000

0.2

0.4

0.6

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

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:

First Prototypes in Q1, 2012

LAMDA GUARD LTD.

London, UK

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

Kallos et al., RADIO SCIENCE, VOL. 46, RS0E06, (2011)

Kallos et al., PHYSICAL REVIEW A 79, 063825 2009; Zhang et al., PRL 106, 033901 (2011);

T. Scharf, Polarized Light in Liquid Crystals and Polymers; http://en.wikipedia.org/wiki/Distributed_Bragg_reflector

• Δλ

T. Scharf, Polarized Light in Liquid Crystals and Polymers; TyrionL (Own work) [Public domain], via Wikimedia Commons

Hwang et al., nature materials | VOL 4 | MAY 2005

Polarized Light in Liquid Crystals and Polymers; Ha et al., Nature Materials, vol.7, pp.43-47 (2008)

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

• λ

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