Hand-Held Optoelectronic Particulate Monitors

Optoelectronic instruments are being developed for use in measuring the concentrations and sizes of microscopic particles suspended in air. The instruments could be used, for example, to detect smoke, explosive dust in grain elevators, or toxic dusts in industrial buildings. Like some older, laboratory-bench-style particulate monitors, these instruments are based on diffraction of light by particles. However, these instruments are much smaller; exploiting recent advances in optics, electronics, and packaging, they are miniaturized into compact, hand-held units.