Contactless Optical Liquid Identifier

This paper presents the development of a portable device that can be used for liquid identification using the concept of Beer-Lambert law. The final device can recognize up to 30 different materials in their liquid state and provides some other useful features that can enhance its operation. The user can set a group of 30 liquids according to specific needs and applications. The device can provide the user with some specific settings to start the measurements. The volume of a fluid is identified by a 4 mL sample inserted in the cuvette, then the user can start measuring the concentration of some common solvents like methanol, ethanol, etc. by passing a light of different wavelengths through the sample. The amount of the transferred light is measured using photodetectors and the readings depend on the amount of absorption. The amount of absorption depends on the sample types, colors, contents, and concentrations, so it is used as the main indicator to identify a specific sample.