Pyroelectric sensors for the security system application

1
Pyroelectric sensors for the security system
application
EE552 sensor actuator

• Instructor Dr. Mohan Krishnan
• Team Members Chun-Chin You
• Kazi ahmed
• December 8, 2005

2
Introduction

• Overview of The Infrared Radiation
• The Pyroelectric Sensor
• What is the Pyroelectric Sensor ?
• How the Pyroelectric sensor work ?
• Project Description
• Actual Setup
• Limitations
• Results
• Questions ?

3
The Infrared Radiation

• Infrared radiation wavelength is longer than
  visible light.
• Objects generate heat and also generate
  infrared radiation.
• objects include animals and the human body
  whose radiation is strongest at a wavelength of
  9.4um.

4
The Pyroelectric Sensor

• What is the Pyroelectric Sensor ?
• The Pyroelectric sensor is made of a crystalline
  material
• The amount of radiation striking the crystal
  changes, the amount of charge also changes.
• Typical crystalline material
• Terbium Gallium Garnet (TGG)
• lead titanate zirconate (PZT)

5
The Pyroelectric Sensor

• Microstructures of
• mixed PZT/alumina

6
The Pyroelectric Sensor

• How the Pyroelectric sensor work ?
• Work theory
• The pyroelectric sensor has two sensing elements.

7
The Pyroelectric Sensor - Our sensor ( IR 442)
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The Pyroelectric Sensor

• -The output signal waveform shows that first a
  positive,
• -then zero and then a negative transition results

9
The Pyroelectric Sensor
- Our sensor ( IR 442)
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The Pyroelectric Sensor

• Focusing device

• The Fresnel lens is made of an infrared
  transmitting material

11
Project description

• Overview of the system
• Use the pyroelectric sensor IR 442
  servo,
• and web cam to build
• the security system.

12
Project description

• System Schematic

Record the data
Servo2 indicates the max value and holds the
position
start
Max value
Servo1 moves, Sensor scans
Servo1 and sensor go back to start but no
recording data
13
Actual Setup
14
Limitations

• Dont let the sensor face to the sun.
• Dont let the sensor close the high heat source.
• The scan distance of the detection of the sensor
  is about 4.5m in our project .

15
Results (how did it work?)

• See !

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Questions ?

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