“La spettroscopia di riflettanza risolta nel tempo (TRS): principi ed applicazioni”
Alessandro Torricelli
Winter School«Le tecniche spettroscopiche: strumenti innovativi applicati all’analisi dei settori
ambientale ed agro-alimentare –nuove sfide per il futuro»
28 January 2015, Milano
Politecnico di Milano (PoliMi)Teaching & Research University
PoliMi since 1863
1863 – 2013150 years
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150 years
EngineeringArchitectureDesign
Department of PhysicsPhotonics for Health, Food and Cultural Heritage
Head: Rinaldo CubedduStaff @PoliMi Antonio Pifferi
Paola TaroniAlessandro TorricelliGianluca ValentiniAndrea BassiDaniela ComelliCosimo D’AndreaDavide ContiniAlberto Dalla Mora
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Alberto Dalla Mora
Staff @ IFN-CNR Lorenzo SpinelliAustin NevinAndrea Farina
Post-Docs Ilaria BargigiaGiovanna QuartoRebecca ReMaristella VanoliLucia Zucchelli + PhD Students
+ Undergraduate Students+ Facilities (mechanic and electronic workshop)
Photonics for Health, Food and Cultural Heritage Research activities: overview
Health In vivo Tissue Spectroscopy Optical Mammography Tissue Oximetry and Functional Imaging of the Brain Fluorescence Lifetime Imaging in biology and medicine
Food nondestructive assessment of
internal defects by pulsed NIR
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Cultural Heritage Photoablation and Material Processing Fluorescence Spectroscopy and Imaging Multispectral Imaging and Colorimetry
internal defects by pulsed NIR nondestructive maturity
assessment at harvest
Photonics for Health, Food and Cultural Heritage Laboratories
Time-resolved systems mode-locking of dye, gas and solid state lasers time-correlated single-photon counting (TCSPC) time-gated imaging
Spectral-domain tunable laser sources broadband detectors
TEMPORAL⇒ fast!
SPECTRAL⇒ colored!
fNIRS Lab
NIRf Lab
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• functional near infrared spectroscopy - fNIRS Lab• diffuse spectroscopy - DiffS Lab• optical mammography - Mammot Lab• molecular imaging - Molim Lab• near infrared spectroscopy for food - NIRf Lab• imaging spectroscopy for cultural heritage - ARTIS Lab• ultras for biomedicine - UB Lab
Spatial-domain scanning systems or camera multi-channel systems
Temporal-domain fast acquisition rate
SPATIAL⇒ wide!
DiffS Lab
Mammot Lab
Fluo Lab
UB Lab
Molim Lab
ISCH Lab
Can light penetrate biological tissues?
Georges de La Tour (1593 – 1652)
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St Joseph, 1642, Louvre, Paris Thanks to Marco Ferrari (UnivAQ)
Light absorption in the NIRbiological tissue
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The therapeutic and diagnostic window
Light absorption in the NIRfruit
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Light propagation in diffusive media:absorption and scattering
clear diffusive
Scattering: related to tissue structure
Scattering coefficient:
Absorption: related to tissue components
Absorption coefficient:µa = 1/la (cm-1)
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Linout
aeII µ−=
Scattering coefficient:µs = 1/ls (cm-1)
( )Linout
saeII µµ +−=
interplay between absorption and scattering
Time-resolved Reflectance Spectroscopy (TRS)Basics
Intensity
Laser pulse
10-100 ps duration
Remitted pulse
log10I
µ’s
time
Effect of scattering
Changes in peak position!
Slope does not change
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µ’s , µa
ρtime (1-10 ns)
time
µa
time
log10IEffect of absorption
Changes in slopePeak position does not change
Conservation of energy in a small volume dV in a given direction Ω
(1) (3) (4) (5)
Light source
(2)
Radiative Transport Equation (RTE)
επ
+∫ )•′µ+µ−µ−∇•−=∂∂
4ssa dˆˆ(vvvˆv Ωnpnnn
t
nsss
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sPhotons outPhotons in
Photons scattered to another direction
Photons scattered from another direction (s’) to direction of interest (s)
dV
Light source
Photons absorbed
Radiative Transport Equation
Expansion methods
•PN approximation:
P0 = Diffusion Theory
P = Diffusing Wave
Stochastic methods
• Monte Carlo
Solutions of the RTE
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P1 = Diffusing Wave
P3 = …
Discretisation methods
• Discrete ordinates
• 2-flux or Kubelka-Munk
• Adding-double method
• Finite Element Method
Hybrid methods
• Paasschens (1997)
• Martelli (2008)
• Kienle (2011)
Infinite Semi-infinite
Slab Parallelepiped
Photon Diffusionsolutions for other geometries
2 layer
N layers
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Sphere Cylinder
F.Martelli et al. Photon migration through diffusive media:Theories and software (SPIE book, 2010)
inhomogeneity
Photon Diffusiontime-resolved reflectance
∑∞+
−∞=
−−
−×
−−
−=m
mm
mm
a
Dvt
zz
Dvt
zz
tDv
Dvtvt
tR4
exp4
exp)4(2
4exp
),(2
,4,4
2,3
,32/52/3
2
π
ρµρ
1.000laser pulseTRS datamodel
)=∂
)Φ∂+)Φµ+)Φ∇− tSt
tttD ,(
,(
v
1,(,( 0a
2 rr
rr
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0.001
0.010
0.100
0 1000 2000 3000 4000 5000
time (ps)
inte
nsity
(a.u
.)
µ’s , µa
ρ
Time Frequency
R(ρ,t)
t
R(ρ,ω)
t
ρ ρ
Time, Frequency, Space and Angle domain measurein diffusive media
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Time Frequency
AngleSpace
CW CWR(ρ)
ρ
R(θ)
θ
θρ
Laboratory set-up for broadband TRS
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Fully automated system
spectral range: 540 -1100 nm Pifferi et al., Review of Scientific Instrument 78, 053103 (2007)
Laboratory set-up for broadband TRS
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Fully automated system
spectral range: 540 -1100 nm Pifferi et al., Review of Scientific Instrument 78, 053103 (2007)
Optical characterisation of biological tissuesfemale breast
0,15
0,20
0,25
0,30
abso
rptio
n co
effic
ient
(cm
-1)
HbO2 [43 uM]Hb [22 uM]Water [34%]Lipid [53%]
Σ= λελµ iicia
15
20
redu
ced
scat
terin
g (c
m-1
)
Empirical approximation to Mie theory
bcbnabxas −==≈
λλπµ r2'
Absorption spectrum and tissue constituents Scatteri ng spectrum and tissue structure
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0,00
0,05
0,10
0,15
600 650 700 750 800 850 900 950 1000
wavelength (nm)
abso
rptio
n co
effic
ient
(cm
Σ= λελµ iicia
Beer’s law
0
5
10
600 650 700 750 800 850 900 950 1000
wavelength (nm)re
duce
d sc
atte
ring
(cm
a ⇔ density of scatterers
b ⇔ equivalent size of scatterers
Breast Absorption spectra: Inter-subject variation
R3 PT-40 DC-29 EL-34 LT-23 FM-50 KE-31water 72% 48% 36% 31% 22% 12%lipids 5% 41% 35% 48% 66% 71%tHb/µM 15.3 25 11 20 16 15SO2 63% 75% 62% 73% 59% 81%
0.20
0.25
0.30
0.35
0.40
abso
rptio
n (c
m-1
)
Fibrous Adipose
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0.00
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0.20
600 650 700 750 800 850 900 950 1000 1050
wavelength (nm)
abso
rptio
n (c
m
BreastScattering spectra: Inter-subject variation
T PT-40 DC-29 EL-34 LT-23 FM-50 KE-31a 9.3 8.9 6.8 11.7 11.0 9.6b 2.0 1.4 2.0 0.7 0.7 0.7
15
20
25
redu
ced
scat
terin
g (c
m-1
)
µ’s = aλ-b
Density
Size
Fibrous Adipose
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0
5
10
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wavelength (nm)
redu
ced
scat
terin
g (c
m
A.Pifferi et al., J. Biomed. Opt. 9:1143-1151, (2004)
Time-resolved optical mammograph
laser heads
905 nm
683 nm
785 nm
637 nm
driver
sync
coupler
930 nm
975 nm
1060 nm
variable attenuators
• Continuous movement:
• Laser driver: “Sepia” (PicoQuant)
• Repetition rate: 20 MHz
• Pulse duration: 180-400 ps
• Average incident power: 1-1.5 mW
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fiber bundle
AMP
TCSPC board
sync
NIR PMT
VIS PMT
sync
collimator
cut-off filter variable attenuators
optics
XY translation stage
personal computer
AMP
TCSPC board
• Continuous movement:stepping motors & Counter/Timer PC board
• Maximum scan area: 180 mm x 240 mm
• Step interval: 1 mm
• Measurement time: 25 ms per point
• Photomultipliers (Hamamatsu, KK):
VIS: R5900U-01-L16, 150 ps TTS, λ < 850 nm
NIR: H7422P-60, 450 ps TTS, λ < 1100 nm
• TCSPC board (SPC-134, Becker & Hickl):
4 independent channels
16 MHz max count rate
Optical MammographyOPTIMAMM Project FP5 (2000-2003)
Patient #47, oblique view
age: 36 ythickness = 5.7 cmLesion size = 3.0 cmLesion type = tumor
S02 tHb
R LR L
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52%-89% 17 - 91µM62%-95% 16 - 66µM
Type View Cases Detection rate FailuresCorrected
detection rate
Cancer 2 41 73% 80%1 9 89% 4 96%
0 6 11%
Cyst 2 59 72% 8 83%1 5 78% 3 90%
0 18 22%
Fibroadenoma 2 17 33% 2 39%1 5 43% 5 50%
0 29 57%Taroni et al., TRTC 4:527-537 (2005).
Clinical study (225 lesion)
Multi-channel time-domain system for functional nea r infrared spectroscopy (fNIRS)
µCHIP
delay
2x2 fused splitter
50%
50%
2x4 fusedsplitter
R1R2
R3R4
S9
S8
S1
sync
820 nm
690 nm
Laserdriver
variable ND
variable ND
1x9 fiber switch
1x9 fiber switch
clock
PicoQuantPDL800
PiezojenaF-SM19
OZOpticsVISNIR5050
µCHIP
delay
2x2 fused splitter
50%
50%
2x4 fusedsplitter
R1R2
R3R4
S9
S8
S1
sync
820 nm
690 nm
Laserdriver
variable ND
variable ND
1x9 fiber switch
1x9 fiber switch
clock
PicoQuantPDL800
PiezojenaF-SM19
OZOpticsVISNIR5050
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clock
µCHIPS16
4 anodesPMT-1
4 anodesPMT-2
4 anodesPMT-3
4 anodesPMT-4
4 chrouter-1
4 chrouter-2
4 chrouter-3
4 chrouter-4
8 champ-1
8 champ-2
F1
F16
TCSPC-1
TCSPC-2
TCSPC-3
TCSPC-4
HamamatsuR5900-20-M4
Becker & Hickl, SPC-134, HRT-41, HAFC-26
Microchip TechnologydsPIC30F6014
Contini et al. Opt Express14:5418-5432 (2006)
clock
µCHIPS16
4 anodesPMT-1
4 anodesPMT-2
4 anodesPMT-3
4 anodesPMT-4
4 chrouter-1
4 chrouter-2
4 chrouter-3
4 chrouter-4
8 champ-1
8 champ-2
F1
F16
TCSPC-1
TCSPC-2
TCSPC-3
TCSPC-4
HamamatsuR5900-20-M4
Becker & Hickl, SPC-134, HRT-41, HAFC-26
Microchip TechnologydsPIC30F6014
Contini et al. Opt Express14:5418-5432 (2006)
Can light penetrate biological tissues?
Georges de La Tour (1593 – 1652)
Nome relatoreA. Torricelli
St Joseph, 1642, Louvre, Paris Thanks to Marco Ferrari (UnivAQ)
Noninvasive imaging of brain function and disease b y pulsed near infrared light (nEUROPt FP7 2008-2012)
healthy ULD patientsA, D:O2Hb and HHb time-courses in themost reactive channel and thecorresponding GLM activationmaps.
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In collaboration with: I.Gilioli, S.Franceschetti, F. Panzica, E.Visani @ IRCCS Besta Milan, Italy
B, E:BOLD signal extracted from theactive cluster and fMRI maps.
An optical neuro-monitor of cerebral oxygen metabol ismand blood flow for neonatology (BabyLux ICT CIP 620 996)
• The BabyLux project aims to provide a
precise, accurate, and robust
integrated system to continuously
monitoring cerebral blood flow,
oxygen metabolism, and oxygenation
in critically ill newborn babies.
• The instrument must be easy to
operate by busy clinical staff and
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operate by busy clinical staff and
must be ready for integration into a
generic neonatal intensive care
environment.
• The proposed solution will integrate
two advanced photonic techniques:
time resolved near-infrared
spectroscopy (TRS) and diffuse
correlation spectroscopy (DCS).
Started on 1st January 20149 European partnersCoordinated by PoliMi
Photonics for Health Photonics for Food
H BC
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Photonics for Food @ PoliMiResearch activities
DIFFRUIT, EU FP4, 1996-1999 TRS APPLE, MAFF (UK), 2000 AGROTEC, MIUR (I), 2000-2002 CUSBO, LASERLAB, EU FP5+FP6+FP7, 2004-2014 INSIDEFOOD, EU FP7 2009-2013 TROPICO, Regione Lombardia (I), 2010-2012 3D Mosaic, EU ICT-AGRI, 2011-2013 USER-PA EU ICT-AGRI 2013-2016
Projects
Publications (2001-2013) >30 papers published on peer reviewed international journals >30 papers on international books and proceedings
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Collaborations
>30 papers on international books and proceedings >30 talks on international conferences
CRA-IAA, Milan (I), Paola Eccher-Zerbini , Anna Rizzolo, Maristella Vanoli, Maurizio Grassi Laimburg (I), Angelo Zanella Agricultural Research Organization, Bet Dagan (Israel), Susan Lurie, Victor Alchanitis Wageningen Universiteit (NL), Pol Tijskens, Olaf Van Kooten, Rob Schouten Planteforsk, Lofthus (N), Eivind Vangdal Potsdam (D), Manuela Zude-Sasse Leuven (B), Bart Nicolai, Bert Verlinden, Wouter Sayes, Pieter Verboven, Maarten Hertog UPM, ETSI Agronomos Madrid (E), Margarita Ruiz-Altisent, Constantino Valero Horiculture Research International, East Malling, (UK) - David Johnson, Colin Dover
Photonics for Food @ PoliMiMain applications
Non destructive optical characterisation of internal optical propertiesand correlation with quality parameters• Basic studies in apples, kiwifruits, nectarines, to matoes, …• Changes in optical properties during growth in Elst ar apples and Tophit plums• Texture in Jonagored apples, Braeburn apples and Pin k Lady apples during storage
Non destructive detection of internal disorders and defects• Browning in Granny Smith apples, Braeburn apples an d Conference pears• Watercore in Fuji apples
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• Watercore in Fuji apples• Mealiness in Braeburn apples and Jonagored apples• Chilling injuries in Jubileum plums and Morsiani nect arines
Non destructive assessment of fruit maturity at harvestand correlation with quality parameters• Basic studies in apples, kiwifruits, nectarines, pe aches, mangoes, …• Sensory attributes, aroma composition, ethylene pro duction Ambra nectarines• Softening prediction (based on biological age) in S pring Bright nectarines
and in Tommy Atkins mangoes
Optical characterization of foodsabsorption and scattering spectra
0.3
0.4
0.5
abso
rptio
n (c
m-1
)
apple
kiwifruit
15
20
25
tran
spor
t sca
tterin
g (c
m-1
)
apple
kiwifruit
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0.0
0.1
0.2
650 700 750 800 850 900 950 1000
wavelength (nm)
abso
rptio
n (c
m
0
5
10
650 700 750 800 850 900 950 1000
wavelength (nm)
tran
spor
t sca
tterin
g (c
m
Cubeddu et al., Applied Optics 40:538-543 (2001)
8
10
12
14
16
tran
spor
t sca
tterin
g (c
m-1
)
Optical characterization of foodseffect of skin: Apple (cv. Golden Delicious)
0.04
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abso
rptio
n (c
m-1
)
peeledintact
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0
2
4
6
600 625 650 675 700
wavelength (nm)
tran
spor
t sca
tterin
g (c
m
peeledintact
0.00
0.02
0.04
600 625 650 675 700
wavelength (nm)
abso
rptio
n (c
m
Optical characterization of foodseffect of skin: Mango (cv. Palmer)
Green skin
0
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500 550 600 650 700 750 800 850 900
abso
rptio
n (c
m-1
)
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scat
terin
g (c
m-1
)
0.0
0.5
1.0
1.5
abso
rban
ce
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Red skin
500 550 600 650 700 750 800 850 900
wavelength (nm)500 550 600 650 700 750 800 850 900
wavelength (nm)
0
0.1
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500 550 600 650 700 750 800 850 900
wavelength (nm)
abso
rptio
n (c
m-1
)
0
5
10
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25
30
500 550 600 650 700 750 800 850 900
wavelength (nm)
scat
terin
g (c
m-1
)
0.0350 400 450 500 550 600 650 700 750
wavelength (nm)
0.0
0.5
1.0
1.5
350 400 450 500 550 600 650 700 750
wavelength (nm)
abso
rban
ce
Optical properties during growthAbsorption spectra
Plum Apple
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GrapefruitChlorophyll breakdown in plum and apple, almost no changes in grapefruit.
Optical properties during growthScattering spectra
Plum
Apple
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Grapefruit
Large changes during growth in the scattering properties for plum and grapefruit, minor changes for apple.
Optical propertiesEffect of layered structure in grapefruit
100
1000
10000
coun
ts (
ph)
IRF (a.u.)
DTOF_1.5cm
DTOF_2.5cm
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pulp
albedo
skin
1
10
0 1000 2000 3000 4000 5000 6000 7000 8000
coun
ts (
ph)
time (ps)
Shorter distance: early photons travel in the albedo, late photons in the pulpLonger distance: photon-path is mainly in the pulp
Nondestructive detection of internal defectsBrown heart in Conference pears
A0.06
0.08
0.10
abso
rptio
n (c
m-1
)
R3 (BH)
R3 (sound)
R3 (BH - sound)
µa (cm-1)@ 720 nm
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0.00
0.02
0.04
0.06
0.08
0.10A
H
G
F
E
D
C
B
0.00
0.02
0.04
710 730 750 770 790 810 830 850
wavelength (nm)
abso
rptio
n (c
m
µa (cm-1)@ 720 nm
Eccher Zerbini et al., Postharvest Biology and Technology 25:87-99 (2002)
Measurement campaignsNondestructive assessment of maturity at harvest
10
20
30
40
50
60
70
80
firm
ness
N
0.090.10.140.180.20.270.30.390.42overripe
ready-firmtransportable
dangerously hardnever ripe
ready-ripe
10
20
30
40
50
60
70
80
firm
ness
N
0.090.10.140.180.20.270.30.390.42overripe
ready-firmtransportable
dangerously hardnever ripe
ready-ripe
( ) minminmax
*minmax1
Fe
FFF
Ff ttFFk+
+
−=
∆+⋅−⋅
)
+−
=∆ β
µµ
α 1log*a
maxa,Ft
6
7
sens
ory
firm
ness
sco
re
.
5 6 13
spots with decay
overly soft spots
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0
10
0 2 4 6 8 10 12
days at 20°C after harvest
0
10
0 2 4 6 8 10 12
days at 20°C after harvest
0
1
2
3
4
5
overripe ready-ripe
ready-firm
trans-portable
danger.hard
neverripe
class of usability
sens
ory
firm
ness
sco
re
.
soft
softer
seems soft
very firm
firm
Eccher Zerbini et al., Postharvest Biology and Technology 39:223-232 (2006) Tijskens et al., Int. J. Postharvest Technology and Innovation, 1 (2), 178-188 (2006)
Tijskens et al., Postharvest Biology and Technology 45:204-213 (2007)Rizzolo et al., Biosystems Engineering (2009 in press)
TRS measurements:Absorption spectra: µ a
Day 0 Day 5
Maturity at harvest and shelf lifein Tommy Atkins mangoes
chlorophyll
carotenoids
Nome relatoreA. Torricelli IC NIRS 2013 – A1 O 094
540 nm
650 nm
TRS measurements:Absorption spectra: µ a
Maturity at harvest and shelf lifein Tommy Atkins mangoes
chlorophyll carotenoids
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Chlorophyll-a and carotenoids estimation from TRSOpen problem: extinction coefficient for carotenoids in vivo
TRS set-up @PoliMi (Photonics for Food)
Laboratory based set-up (time sharing with Photonic s for Health):1) Broad band (450-1700 nm) TRS
ps supercontinuum laser, fast detectors, and TCSPC
2) fs laser + streak camera TRSoperative since September 2013
Transportable set -up
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Transportable set -up3) Dual-wavelength (670 nm, 780 nm) TRS
ps diode laser heads, metal channel dynode PMT, and TCSPC
4) Multi-wavelength (14 wavelengths in the 500-900 nm range) TRSps supercontinuum laser, hybrid PMT, and TCSPC
1) Broad band (450-1700 nm) TRS
ps white light laser
NKT Photonics SuperK Extreme
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Bassi et al., Opt Expr (2007)
Becker-HicklSPC130
MPD
Hybrid PMTNIR PMT1NIR PMT2
2) fs laser + Streak camera
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Hamamatsu Photonics
+++ temporal resolution+ sensitivity
http://sales.hamamatsu.com/en/products/system-division/ultra-fast/streak-systems.php
3) Dual-wavelength transportable system for TRS
laser heads
750 nm
670 nmdriver
fiber optic swtch
PMTampTCSPCsync
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filters and optics
Cubeddu et al., Appl Spectroscopy 55:1368-1374 (2001)Torricelli et al. Sens. & Instrumen. Food Qual. 2:82–89 (2008)
Laser source:
Supercontinuum fiber laser
− spectral range: 450-1600 nm
− power: 6 W
− frequency: 40 MHz
Wavelength selection:
Filter wheel
− spectral range: 540-900 nm
Detector:
Hybrid PMT
− no afterpulse
− time response: 250 ps
4) Multi-wavelength (500-900 nm range) transportable TRS
Supercontinuumlaser
grin fiber∅ =100μm
Large areadetector
Objective 10x Step-index fiber∅ =1mmSupercontinuum
laserSupercontinuum
lasergrin fiber∅ =100μm
Large areadetector
Large areadetector
Objective 10x Step-index fiber∅ =1mm
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TCSPCSYNC
CFD
Time resolution:
Time-Correlated Single-Photon Counting:
− high dynamic range
− suitable for faint signal
− time resolution: up to 1 ps
SY
NC
Filter wheelSample
Filter wheelFilter wheelSampleSample
Filter wheel
8 absorption nominal values:
0 : 0.07 : 0.49 cm-1 (label 1 -> 8)
4 reduced scattering nominal values:
5 : 5 : 20 cm-1 (label A -> D)
Robust calibrations….Solid phantoms: Epoxy based
Well established solutionabsorption
Scatt
erin
g
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New series: 2.5, 7.5, 12.5 17.5 cm-1 nominal reduced scattering
Development of a transportable TRS set-upfor measurements in the orchards
2x1 combiner
100um GIλ1PD
L d
riv
er
λ2
laser head
variable attenuator fiber bundle
1 mm POF GI
cfdSPAD
lens, IF filter, shutter
SPADlens,
IF filter, shutter
TCSPC board
cfdTCSPC board
Scheme of the TRS setup
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light source: pulsed diode laser (LDH series PicoQuant GmbH, Germany)detection: SPAD detectors (Excelitas Inc., Canada)acquisition: TCSPC board (Becker&Hickl GmbH, Germany)power supply: portable (gasoline), inverter technology (i20, Honda, Japan)
80 MHz sync
80 MHz sync
shutter
Development of a transportable TRS set-upfor measurements in the orchards
Photo of the TRS set-up
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Field trials 2014Preliminary results
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Field trials 2014Preliminary results
Absorption coefficient
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Chlorophyll absorption decreases during fruit growth(agreement with Seifert et al. Physiol Plantarum 2014)
Field trials 2014Preliminary results
Scattering coefficient
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Scattering decreases during fruit growth(agreement with Seifert et al. Physiol Plantarum 2014)
Evolution of TRS set-upTowards a smart photonic chip for TRS
Transportable>2013
Handheld>2016
Canopy>2018
Nome relatoreA. Torricelli
Reducing size and cost ...
Evolution of TRS set-upThe future is near …
fNIRS – brain response to finger tapping
Nome relatoreA. Torricelli
1 wavelength1 channelExternal power supply
Conclusion and future perspectives
• Time-resolved reflectance spectroscopy (TRS) naturally yieldsdiscrimination between light absorption (related to tissue constituents)and light scattering (related to tissue structure)
• Physical and mathematical models for TRS are available and allowquantitative data analysis for non destructive fruit quality assessment
Nome relatoreA. Torricelli
• We have demonstrated in the last years several applications of TRS inthe food sector, mainly at research level
• We are at the forefront of a new era where recent advances inphotonic technologies might allow TRS to bridge the gap betweenresearch and market (the development is mostly driven by thebiomedical sector)
Acknowledgements
• CNR-IFN, Milan (Italy) Lorenzo Spinelli
• Politecnico di Milano - Dipartimento di Fisica, Milan (Italy) Antonio Pifferi Davide Contini Alberto Dalla Mora
• CRA-IAA (ex IVTPA), Milan (Italy)
Nome relatoreA. Torricelli
• CRA-IAA (ex IVTPA), Milan (Italy) Anna Rizzolo Maristella Vanoli Maurizio Grassi (Paola Eccher Zerbini)