A mechanically resonant torsional spring scanner was previously designed for light dispersion application. However, the effects of mountings and pressure variation on the damping characteristic of the scanner were not well studied. In this study, the damping characteristics of the linear optical scanner with torsional spring mechanism are investigated with a mathematical model and various experiments. To examine the scanner's free response profile when the resonance frequency and damping ratio were varied, a damping model was established based on experimental results. Several experiments were performed to investigate the damping characteristics when environmental pressure and scanner mounting are changed. The scanner mountings consist of rigid mounting, spring demounting, and the use of various dampers. In general, the scanner damping was shown to be greater at higher atmospheric pressures when the scanner was mounted on a foam damper.