Pryo-electric Sensors Human Detection

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Pryo-electric SensorsHuman Detection

• Jeanell Sealy
• ECE 5320 - Mechatronics
• Assignment 1

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Outline

• References
• Further Exploration Sources
• Major Applications
• Basic working Principles
• Typical Sample Configuration in an application
• Major Specifications
• Limitations
• Cost Information/ Where to Buy

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References

• Global Corporation
• Murata Manufacturing
• Processing of Signal of Piezoelectric Sensor in
  Laser Energy Meter Poznan University of
  Technology, Poland

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Further Exploration Sources

• http//www.cdc.gov/nasd/docs/d001501-d001600/d0015
  03/d001503.html
• http//www.dexterresearch.com/pdf/Thermacon_T80_S8
  0.pdf
• http//www.aps.org/meet/MAR04/baps/abs/S4050.html

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Major Applications

• Security
• Lighting Appliances
• Household or other Appliances
• Heat Sensing
• Human or Mammal Detection

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Basic Working Principles

• Crystalline material generates a surface electric
  charge when exposed to heat from infrared
  radiation
• Sensitive FET is build into the sensor to measure
  changes in charge
• Filter window is added to sensor device to limit
  incoming radiation to the 8-14µm range
• Configurations can cancel signals caused by
  vibration, temperature changes and sunlight.

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Basic Working Principles

• What the typical human detection PIR will look
  like
• Murata Manufacturing

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Typical Sample Configuration in an Application

• Global Corporation

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Typical Sample Configuration in an Application

• Global Corporation

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Typical Sample Configuration in an Application

• Infrared frequency range for human detection
  5-14µm
• Filter to remove noise from power supply
• Motion direction is detected by a more
  positive/negative voltage response
• 5V required for accurate detection
• Frensel Lens for Human Detection

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Typical Sample Configuration in an Application

• Frensel Lenses
• A Frensel lens is a Plano Convex lens that has
  been collapsed on itself to form a flat lens that
  retains its optical characteristics but is much
  smaller in thickness and therefore has less
  absorption losses

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Major Specifications

• High Sensitivity and Excellent S/N ratio
• High Stability to the temperature change
• Slight movement can be detectable
• Non directional sensing with wide field of view
  (approx 41 degrees)
• High immunity to external noise (Vibration, RFI,
  etc.)
• Supply voltage (3 to 15 V)
• Responsivity 3.3mV (typical)

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Limitations

• Viewing angle is regulated by the lens
• Limited to Temperature ranges detectably below or
  above body temperature (98.6 degrees)
• Requires large amplification low noise immunity

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Cost Information/Where to Buy

• Cost Information
• Approximately 2-4 each unit
• Where to Buy
• http//www.scitec.uk.com/pyroelectric/pyroelectric
  
• http//mstmicro.com/sensor/sensor.html