An automatic crystal alignment system for producing high quality oscillators

Crystal oscillator products are widely used in a wide range of industry applications, such as global positioning satellites, wireless applications and cellular networks technologies. The quality of crystal oscillators normally depends on how they are cut from crystal bars. However, the current manual crystal bar alignment procedure is very much dependant on operator skill, and is not repeatable, leading to variations of the oscillators' quality. The research is to develop an automated alignment system for aligning quartz crystal bars prior to being cut. The paper investigates the magnitude of the effects of rotational misalignments in the y-axis. Axis errors in the y-axis are found to create x-axis misalignments of up to thirty percent of the y-axis error. The feasibility of such a system is also analysed in terms of the required mechanical and electrical requirements, and a test-bed is built to carry out future experiments and automate the alignment process.