The main aim of this research is to propose a new and low cost angular speed measurement based on optical imaging technique. A photo sensor available in computer mouse is implemented as a contactless speed measurement transducer device. The photo mouse sensor output is used to convert the rotating speed of motor shaft, revolutions per minute (RPM), to linear speed. A software program written in C-sharp language is employed to determine the speed and display it in RPM. A motor with maximum rated speed of 2850 RPM is tested at different speeds. Performance comparison is founded by using speed tachometer as a reference measurement. The maximum and minimum percentage error found is 0.099% and 0.05% respectively. Results validated the effectiveness of the proposed technique and its potential applications in electric drives and automation.