Electronic Design of an Acousto Optic Tunable All Fiber Spectrometer
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Electronic Design of Electronic Design of an Acousto Optic an Acousto Optic Tunable All Fiber Tunable All Fiber Spectrometer Spectrometer Tanuja A. Mouli Tanuja A. Mouli Faculty Mentor: Faculty Mentor: Professor Henry P. Lee Professor Henry P. Lee Graduate Student: Graduate Student: Fares Alhassen Fares Alhassen
description
Electronic Design of an Acousto Optic Tunable All Fiber Spectrometer. Tanuja A. Mouli Faculty Mentor: Professor Henry P. Lee Graduate Student: Fares Alhassen. The Project: Big Picture. Unknown Wavelength. Acousto Optic Tunable Filter (AOTF). Metal Frame. Optical Fiber. PZT. - PowerPoint PPT Presentation
Transcript of Electronic Design of an Acousto Optic Tunable All Fiber Spectrometer
Electronic Design of an Electronic Design of an Acousto Optic Tunable All Acousto Optic Tunable All
Fiber SpectrometerFiber Spectrometer
Tanuja A. MouliTanuja A. Mouli
Faculty Mentor: Professor Faculty Mentor: Professor Henry P. LeeHenry P. Lee
Graduate Student: Fares Graduate Student: Fares AlhassenAlhassen
The Project: Big PictureThe Project: Big Picture
Unknown Wavelength
Acousto Optic Tunable Filter Acousto Optic Tunable Filter (AOTF) (AOTF)
Metal Frame
Optical FiberPZT
AOTF: The PZTAOTF: The PZT (Piezo Electric Tansducer) (Piezo Electric Tansducer)
AC
•Aluminum cone is attached to PZT disk
•When AC voltage is applied, the cone vibrates up and down
CONE
PZT
The AOTFThe AOTF
PZT and horn
Acoustic wave
RF
(Piezo Electric Transducer)
•When PZT vibrates, it creates a micro acoustic wave
•Tunable filter is created by changing the frequency of PZT
AOTF: Notch FilterAOTF: Notch Filter
Acts to pass wide Acts to pass wide range of range of frequenciesfrequencies
While attenuating While attenuating narrow band of narrow band of frequencies frequencies
-25
-20
-15
-10
-5
0
1557 1557.5 1558 1558.5 1559 1559.5 1560 1560.5
Wavelength (nm)
Tran
smis
sion
(dB
)
AOTFAOTF
PZT
Aluminum Cone
Why use AOTF?Why use AOTF?
AOTF is easily tuned and can be AOTF is easily tuned and can be controlled electronicallycontrolled electronically
Optic fibers have low insertion power Optic fibers have low insertion power lossloss
Original spectrometer used costs 30KOriginal spectrometer used costs 30K Spectrometer built with AOTF will be Spectrometer built with AOTF will be
low cost ($100), compact and low cost ($100), compact and portableportable
Common ApplicationsCommon Applications
– detect chemical compoundsdetect chemical compounds particle sizesparticle sizes VibrationVibration
– acoustic wavesacoustic waves– electric fieldelectric field– fluid flow and temperature fluid flow and temperature
Spectrometric ApplicationsSpectrometric Applications
Broadband Infrared (BBIR)Broadband Infrared (BBIR) Tunable Camera Filter (TCF)Tunable Camera Filter (TCF) Portable Optical Spectra Portable Optical Spectra
Analyzer (POSA)Analyzer (POSA)
The Design of the The Design of the SpectrometerSpectrometer
Microcontroller
VCO
Light Source
AOTF Photodetector (PD)
Current –to- Voltage Conversion
Output Data
RF Amplifier
Schematic: Microcontroller Schematic: Microcontroller Connection with VCO Connection with VCO
In2
Out6
17
4
18
14
8 Out5
In6
Out0
9
127
in2
15
serial out 2
13
In7
Out2
16
6 PIcaxe 18X
In11
3
Out3
serial out
V+
11
5
Out7
0V
MICROCONTROLLER
Out410
Out1
Serial in
Push Button
1 4
2 3
Voltage ControlledOscillator
+
+
Voltage control
+
+
1V
2V
3V
4V
2. Press button again
1. Press button once
Schematic: Current to Voltage Schematic: Current to Voltage Converter Converter
In2
Out6
17
4
18
14
8 Out5
In6
Out0
9
127
in2
15
serial out 2
13
In7
Out2
16
6 PIca
xe 1
8X
In11
3
Out3
serial out
V+
11
5
Out7
0V
MICR
OCON
TROL
LER
Out410
Out1
Serial in+
-
+
-
V1
-
+
OPA6023
26
7 14 5
0+
1k
0
0
Schematic: Overall CircuitSchematic: Overall Circuit
In2
Push Button
1 4
2 3
+
-
In
17
1
Voltage ControlledOscillator
+
-
V1
4
18
14
8
In6
+
Out0
9
Out5
127
in2
-
+
OPA6023
26
7 14 5
PD
15
serial out 2
13
0
In7
Out7
Out2
16
6 PIcaxe 18X
In1
++
1k
1
3
Out3
serial out
AOTF
V+
Out6
RF AMPLIFIER
Light Source
11
freq out
5
out
Out4
Voltage control
0V
Output Data
light
0
MICROCONTROLLER
+
10
0
+
Out1
Serial in
Final CircuitFinal CircuitVCOC-V converter
MCU
ProblemsProblems and Solutions and Solutions
VCO purchased (part VCO purchased (part #SN54LS624) did #SN54LS624) did not output a clean not output a clean sinusoidal.sinusoidal.– A different VCO was A different VCO was
used (MAX038)used (MAX038)
When MAX038 was When MAX038 was connected to connected to microcontroller, the microcontroller, the VCO gets hotVCO gets hot
Results/Results/ConclusionConclusion
Successfully controlled VCOSuccessfully controlled VCO– Need to work on why VCO Need to work on why VCO
gets hot.gets hot. Controlled C-V converterControlled C-V converter Could not view output dataCould not view output data
AcknowledgementsAcknowledgements
Said M. ShokairSaid M. Shokair Dr. Henry P. LeeDr. Henry P. Lee Fares AlhassenFares Alhassen Patrick ChanPatrick Chan Kevin EdmondsKevin Edmonds
UROPUROP UCIUCI IM-SUREIM-SURE
ANY ANY
QUESIONS?QUESIONS?
