Project PRISMProject PRISMOptronics: Protection & Optronics: Protection &

SurveillanceSurveillanceDr Dirk Bezuidenhout

CSIR

Universities InvolvedUniversities Involved

StellenboschPhysics (Dr E Rohwer)Process Eng (Prof H Knoetze)

NMMUPhysics (Prof J Engelbrecht)

RhodesChemistry (Prof T Nyokong)

UKZNComputer Science (Prof J-R Tapamo)Physics (Dr V Couling)

Universities InvolvedUniversities Involved

UJ Electr. & Electronic Eng. (Dr W Clarke)

UPMathematics (Dr R Anguelov)

TUTFrench South African Technical Institute in Electronics (Prof B van Wyk)

Number of StudentsNumber of Students

Nine Departments

Eight Disciplines

Number of Students: 22

PRISM-L: LasersPRISM-L: Lasers

Light SourcesCountermeasuresBeam Propagation

High-power end-pumped High-power end-pumped Nd:YLFNd:YLF

A OM

P um p d iode 1 P um p d iode 2

OC

N d:YLF

R = - 30 m m

R = 150 m m

L1

Reverse Saturable AbsorptionReverse Saturable Absorption

Fibre Laser LaboratoryFibre Laser Laboratory

PRISM-P: PyrophoricsPRISM-P: Pyrophorics

PyrophoricsPyrophorics

Interface with Project COUPLE

PRISM-MPRISM-M

Layout: Missile optics

Semi- conductor MaterialsSemi- conductor Materials

0.30 0.32 0.34 0.52 0.54 0.56 0.58 0.60 0.62 0.64 0.66 0.680.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

Wa

vele

ng

th (

nm

)

400

600

800

1000

2000

SiC

HgTe

CdTe

ZnOGaN

InP

AlSb

InAs InSb

GaSb

AlAsGaP

GaAs

SiEn

erg

y G

ap

(e

V)

Lattice constant (nm)

Bandgap ModificationBandgap ModificationB

an

dg

ap

En

erg

y [

eV

]

0.0 0.2 0.4 0.6 0.8 1.0

0.15

0.25

0.35

0.45

Lat

tice

-mat

ched

to G

aSb

Wa

vele

ng

th [

nm

]

15000

100008000

6000

5000

4000

30003.537 μm

0.089

2 K

300 K

InSbInAs

Sb mole fraction x

4.218 μm

InAs1-XSbX

Bandgap spans strategic 3-7 μm range at low T

Backside IlluminationBackside Illumination

Development of InAs0.91Sb0.09/GaSb backside-illuminated detector

λcut-off ~3.6 μm at 77 K

n:GaSb Substrate

n:InAs

p:InAsSb

Optical Limiters: Electronic Optical Limiters: Electronic structurestructure 2 photon absorption

Singlet states S, triplets TCross sections σ Inter-System Crossing

Desirable properties:high triplet quantum yield σex >> σg

rapid inter-system crossinga long lifetime τT in the triplet stateoptical stabilityHigh damage thresholds for the material

Metallo-phthalocyanines, MPcMetallo-phthalocyanines, MPc

Unsubstituted MPcSubstituted MPc

Peripheral substituent

Axial substituent

SymmetrySymmetryZnPc

-0.15

-0.1

-0.05

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0 1 2 3 4 5 6 7 8

r /Å

z /Å

C2v dome shape is energy minimum

C2v

Highest Occupied Molecular Highest Occupied Molecular Orbital Orbital

ResultsResults

Vibrational frequencies

0

1

2

3

4

5

6

40060080010001200140016001800

Frequency

IR i

nte

nsit

y

Image ProcessingImage Processing

Optical Surveillance PathOptical Surveillance Path

Solar GlintSolar Glint

Discreet Pulse TransformsDiscreet Pulse TransformsDevelop a method for the decomposition of images into 2D block pulsesAnalysis of sea images via discrete pulse decompositionCharacterization of the images of marine background in varying conditionsDeveloping algorithms for identifying anomalies in a sea imageAlgorithms for target detection using the discrete pulse decomposition of the image

Image Processing and Optical Image Processing and Optical TrackingTracking

Optical TrackingOptical Tracking

Image ProcessingImage Processing

Solving the Heat Scintillation Problem in Images(Rishaad Abdoola)

Robust Real-Time Motion Detection

(Petrus Nyathela)

Gated Camera ApplicationsGated Camera Applications

Stress Induced BirefringenceStress Induced Birefringence

Birefringence Map for doublet

QuestionsQuestions