Optical Sensing, PPD71, Particle sensor, dust

Shinyei Technology

Particle Sensing

Particle Sensor Unit PPD71

Based on the light scattering method, it detects airborne particles continuously, then outputs the detection result in UART digital output based on mass concentration (μg/m3).


  • Redesigning sensor structure achives the smallest sensor ever.

  • Digital output by UART communication offers you designing software easily.

  • New optical design and MCU provide better accuracy and fine particle sensing.

  • Using custom-made key optical parts achieves long operating life time with high reliability.

How It Work

  • Heater (resistor) generating updraft. Infrared light beam from LED has been focused with Lens to sensing point at the center.
  • Airborne particles have been taken into the sensor box with the updraft.
  • Particle passing through sensing point scatters light, and receptor receive scattered light through the lens and transformed into pulse signal. Pulse per unit time is proportional to the particle concentration. Pulse signal are to be converted into voltage output. (PPD20V)


Air Purifier, Air Quality Monitor, Air Conditioner, Ventilator