Chaotic Imaging PhD Student: Emiliano Puddu Tutor: Prof. A. Andreoni XX Ciclo di Dottorato A.A....
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Transcript of Chaotic Imaging PhD Student: Emiliano Puddu Tutor: Prof. A. Andreoni XX Ciclo di Dottorato A.A....
Chaotic Imaging
PhD Student: Emiliano PudduTutor: Prof. A. Andreoni
XX Ciclo di DottoratoA.A. 2004/05
Email: [email protected]
Index
Three wave interaction
Chaotic imaging
Image enhancement & recovery
Imaging Configurations
Maxwell’s equations for the three wave interaction
kzjajga=dzda exp*
231
2 3 2 1 2 32 g = ω ω ω η d
123 kkk=Δk
213 ω+ω=ω
...3)3(4220 EdEEP
2 *3 1
expda = jga a j kzdz
kzjajga=dzda exp21
3
k 3
k 2
k 1
z
E2
E1
E3
42 I Type OBaBβ
3k
k 2
k 1
k 3
k 2
k 1
Sum and Difference frequency
Lower frequency fields are injected: Sum frequency interaction
Higher frequency field is injected: Difference frequency interaction
Phases of the involved fields
a)
b)
c)
Virtual image
Virtual image
Real image
a) b) c)
O' O
L
BBO
telescope dO
CCD355 nm
1064 nm
O''
k3
k2
k1
Sum Frequency
532 nm
case a)
dO'
IMAGING CONFIGURATION: I
Real Object O, Virtual Image, O’, transformed into real O’’
O'O
LBBO
telescopedO
x
ldO'
CCD
355 nm
1064 nmO''
k3
k2
k1
Difference Frequency
532 nm
case b)
IMAGING CONFIGURATION : II
Real Object O, Virtual Image, O’, transformed into Real O’’
O BBO
dO'
CCD
355 nm
1064 nmO'
k3
k2
k1
532 nm
dO
case c)
Difference Frequency - Real Object
IMAGING CONFIGURATION : III
Real Object O, Real Image O’
O'O
L BBOdO
CCD
355 nm
1064 nmO''
k3
k2
k1
Difference Frequency
532 nmcase b)
2f 2f
IMAGING CONFIGURATION : IV
Real Object O, transformed into Virtual O’, Real Image O’’
dO’
What if….
…one of the injected beam has thermal statistic?
We realise the situation of…
Puddu et al., O. L. 30, 1294-1296, 2005
…chaotic imaging!
case b) at degeneracy
L1
L2
...
NLC
E1(ω)
E3(2ω)
E2(ω)
U0(x,y)
2f1
2f1 d
d/ 2f2
D
Case b) at degeneracy
Experimental result
The three holes are not recognizable!
L1
L2
...
NLC
E1(ω)
E3(2ω)
E2(ω)
U0(x,y)
2f1
2f1 d
d/ 2f2
D
Fourier optic: interpretation
Correlation protocol
Bondani, Puddu, Andreoni, J.M.O., in press
Geometria d’interazione
2 Ground Glass Plates
Correlation protocol II
6000 samples 250 samples
2
'
f d
ˆ ˆx y x y
Andreoni, Puddu, Bondani, Manuscript in preparation
2 2
, 3 3', ' , ', ' ', ' 'i jG i j a i j i j a i i j j
Phase – Matching conditions in the chaotic imaging
i
j
Image Enhancement
Shift and Average:add only the maps that respect the condition
2
'
f d
Averages over a sample of 7 correlations
Image Recovery
The same procedure is applied to an insufficient sample of images!
Results
Reduction of the noise:
Reduction of the number of the samples: 250 Vs 6000
02.0 Vs 01.0 0.06 Vs 0.10
6000 samples250 samples{
Perspectives:
Can chaotic imaging generate ghost imaging?
Can chaotic imaging be applied to cryptography?
I.E.N. ISTITUTO ELETTRONICO NAZIONALE
GALILEO FERRARIS
Dott. S. Castelletto Dott. I. Degiovanni