The Beckman Coulter Met One/MET ONE Instruments A2100 Laser Particle Counter measures airborne particles in six size ranges at the same time, and displays the number of particles in each range as a cumulative or differential count. The counter is a state-of-the-art laser-based microprocessor-controlled instrument. It provides adjustable count alarms, automatic calibration verification, and computer controlled operation through a serial port.
The A2100 counter's laser and optical lenses create a laser beam that is used to detect particles. The airborne particles pass through the laser beam, deflecting bursts of light onto a solid-state photo diode that converts the light to an electrical pulse. The size of the pulse is proportional to particle size. The microprocessor and its associated circuitry sorts and counts these pulses.