This paper describes the development and implementation of a self-tuning microcontroller-based instrument for measuring different thicknesses of glass and glass substitutes. The instrument’s hardware was successfully tested in the laboratory on coated and uncoated glass under a variety of conditions. It is designed to provide high performance and high precision measuring capability to the system user. The obtained experimental data suggest that the proposed instrument surpasses existing techniques in its accuracy, reliability, simple operation, safety and measuring capability.