Hand-held Breast Cancer Detector - SUNFEST · 2018. 7. 16. · Q2N3904 0 R1 1k 0 V out U1 3 2 7 4 6...
Transcript of Hand-held Breast Cancer Detector - SUNFEST · 2018. 7. 16. · Q2N3904 0 R1 1k 0 V out U1 3 2 7 4 6...
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Hand-held Breast Cancer Detector
J. Miguel OrtigosaElectrical Engineering
Advised by Dr. Britton Chance
Inexpensive and
convenient!
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Breast cancer and methods for its detection
Breast cancer is the most commonly diagnosed cancer: 40,000 women in the U.S. died from the disease in 2002.
Early detection essential for reducing chance of death.
Most common methods of detection:
X-Ray Mammography.MRI Mammography.Ultra-sound Mammography.
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Device Look… Probe: Light and detector
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Objective for Hand-Held Breast Cancer Device
Detect a tumor of a few millimeters in size at a distance of up to 3 cm from the breast surface.
Commercial uses would include:Tumor Localization.Preliminary Screening.
• Mass and Home Screening.
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Detection Method…
Null Plane
L1 L2D
Photon Density Waves
Object
2 cm 2 cm
Amplitude Cancellation in the Null Plane
Photomultiplier Tube Detector
(PMT)
Light emitting diode (LED):- 0 degree phase
LED at 180 degrees
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Detection Method…Monitor Display
Y=Voltage
X=Time
L1
L2
Middle
Plot: Tumor Location
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Block Diagram Analysis
PMTPMT
BPFBPFMonitorMonitor SplitterSplitterSwitchSwitch0℃
180℃
1st Section
2nd Section
3000 Hz3000 HzOscillatorOscillator
SplitterSplitterObjectLED1
LED2
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Problem and Resolution: 1stSection
8
1
4
3
2U1ALF353N
10KR4
24KR6
10K R3
53k R1
53K
R2
12KR5
-5V
+5V
1nF
C1
1nF
C2
D1Diode 1N5400
D2
Diode 1N5400
T?
Trans CT
200
R13
200
R14
D1Diode
D2Diode
10
R15
10
R16
+5V +5V
Problem: Insufficient Intensityand Modulation.
Resolution: Added Transistor with high base resistance.
Results:20-100 mA swing.Clearer signal.
TX1
kbreak
R2
Q1
Q2N3904
0
0
0Q2
Q2N3904
LED
0
V2
0
R3
V1
LED
V4
0
V5
R4
R1
0
V3
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Problem and Resolution: 2ndSection
Problem: Noise.Resolution:
Replaced noisy transformer.Implemented higher order bandpass filter.
Frequency
100Hz 300Hz 1.0KHz 3.0KHz 10KHzV(out3) V(out2)
0V
40V
80V
120VPLOT: Frequency Response
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Room for ImprovementI. Protect PMT from light overexposure.
II. Make better contact during breast navigation andphysically protect PMT.
III. Eliminate Noise from LED sources themselves.
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Innovations in Breast Cancer DetectorI. Shut-off Protection System.
PMT Voltage Input
Supply Voltage
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Innovations in Breast Cancer DetectorII. New Case Design Idea:
Better design for navigation.Physically Protect PMT by using Fiber Optics.
PMT Computer Mouse Design
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Steps for Completion
Assemble new system on Circuit Board or PC Board.
Finish program for Time-Shared System.
Test new completed system on Breast phantom.
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Q & A
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Innovations in Breast Cancer Detector
I. Time-Shared System
LED1
LED3
LED2
LED4
object
Time shared 10HzCONTROL
DAQ cable
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How we can detect tumors…
High Absorption in Tumors
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Block Diagram Analysis
PMTPMT
BPFBPFMonitorMonitor SplitterSplitterSwitchSwitch0℃
180℃
1st Section
2nd Section
3000 Hz3000 HzOscillatorOscillator
SplitterSplitterObject
300 Hz300 Hz SplitterSplitter
LED1
LED2
LED3
LED4
LED1
LED4
LED3
LED2
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Shut-off Schematic
5V5V
0-5V
0
R3
1k
Q1
Q2N3904
0
R1
1k
0
V out
U1
3
27
46
1
5+
-V+
V-OUT
OS1
OS2
0
Photodiode
V12V
0
0
Relay
V source
PMTVoltage Input
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Problem discovered
LED performance:
Low Intensity.Low Modulation swing.
3000 Hz3000 HzOscillatorOscillator SplitterSplitter Object
PMTPMT
LED1
LED2LED1
LED4
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How it works …
II. Photomultiplier Tube (PMT)
PhotocathodeDynodesAnode
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How it works…I. Light Emitting Diodes (LED)
Near Infrared Light (780 nm wavelength).
High Scattering and Low Absorption mediums:
Microscopically, a random walk.
Macroscopically, outgoing spherical wave referred to as the diffuse photon density wave (DPDW).
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PMT Output Signal Filtering Circuit
0
0
out2
0
V1-15
0
R1
10k
R2
100
0
0
R7
1k
R3
750
R6
1k
C3
0.1u
V510
0
R5
750
V410
R8
750
U4
uA741
3
2
74
6
1
5+
-
V+
V-
OUT
OS1
OS2
0
V3-10
C4
0.1u
R11
1k
0
0
out3
R9
750
U3
uA741
3
2
74
6
1
5+
-
V+
V-
OUT
OS1
OS2
V6-10
out1
R12
1k
0
0
I2
0Adc1Aac
V215
C2
0.1u
0
R4
750
C1
0.1u
R10
750
U2A
LM324
1
3
2
41
1
OUT
+
-
V+
V-
0
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Frequency Response
Frequency
100Hz 300Hz 1.0KHz 3.0KHz 10KHzV(out3) V(out2)
0V
40V
80V
120V