A miniaturized photometric ozone sensor using ultraviolet LED with unbalance differential correction and 3D printing.

Ozone (O) sensing is of great significance to discern the ambient virulence from environmental deterioration. We developed a miniature, low power, low cost, and wide-temperature-range (-40 to +85 °C) photometric O sensor for continuous and in-situ ambient O monitoring. The primary innovation in this sensor is the combination of ultraviolet light emitting diodes (UV-LEDs) with unbalanced differential optical measurement with algorithm correction, sensitive electronic module, and 3D printing fabrication. The sensor operated in the Hartley band of O with a UV-LED (258 nm, 1mw) and software phase-sensitive detection. Experimental results showed high performance of the sensor with detection limit of 8 ppb and relative error of 0.22%. The dimension, power, and weight of the sensor are as low as 11.4 × 5 × 2.4 cm, 0.5 W, and 0.1 kg, respectively, much lower than that of most O sensors. We also demonstrated the feasibility of the sensor in continuously O monitoring in an office.