Spirography is a standard neurological test that has been commonly used for essential tremor diagnosis and its severity assessment for years. Spirography requires simple hardware and software for data recording, which perfectly suits for clinical applications by its easy accessibility and useful and rich-information-contained outcomes. However, current spirography analysis is handled by Fourier Transformation (FT) on acquired data only. Further analysis on spirography is limited due to the loss and restraint of information during digitization, and the lack of valid processing procedures. This thesis provides a brief introduction of Essential Tremor and the application of spirography processing. In order to validate the algorithms developed in this study, algorithmic simulations for smooth spirals and spirals with tremor oscillation are created. In the end, current obstacles in spirography analysis and further development direction are discussed. Suggestions to handle patient spirography data are also provided in the last Chapter.