Abstract

Smartphones have demonstrated being attractive tools for illuminance and liquid turbidity measurements. The ambient light sensor and its corresponding mobile application can measure the reduction in illuminance with the distance away from a light source. The indirect measurement of turbidity is performed via the light passing through a solution. The illuminance linearly decreases with the increase in molar concentration of solution and a linear conversion equation to the turbidity can be obtained. By repeating the experiment, the uncertainty in direct measurements of illuminance is less than 1 %, ensuring an appropriate precision for educational and professional uses.