Pyroelectric sensors for the security system application Instructor: Dr. Mohan Krishnan Team Members: Chun-Chin You Kazi ahmed Kazi ahmed December 8, 2005 December 8, 2005

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 ?

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.

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)

The Pyroelectric Sensor Microstructures of Microstructures of mixed PZT/alumina mixed PZT/alumina

The Pyroelectric Sensor How the Pyroelectric sensor work ? How the Pyroelectric sensor work ?  Work theory –The pyroelectric sensor has two sensing elements.

The Pyroelectric Sensor - Our sensor ( IR 442)

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

The Pyroelectric Sensor - Our sensor ( IR 442)

The Pyroelectric Sensor –The Fresnel lens is made of an infrared transmitting material  Focusing device

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

Project description  System Schematic Servo1 moves, Sensor scans start Record the dataServo2 indicates the max value and holds the position Max value Servo1 and sensor go back to start but no recording data

Actual Setup

Limitations  Don’t let the sensor face to the sun.  Don’t let the sensor close the high heat source.  The scan distance of the detection of the sensor is about 4.5m in our project.

Results (how did it work?) Results (how did it work?) See ! See !

Questions ? ??????????????????????? ???????????? ??????????????????????? ????????????