An example method for adjusting the rate of transfer of the execution state of a virtual machine undergoing live migration may comprise determining, by a processor, a first rate being a rate of change of an execution state of a virtual machine undergoing live migration from a first computer system to a second computer system. The projection optics includes a reflection mirror configured to reflect the image light toward the screen, the image light outputted from the image light generator. The second substrate has a second insulating substrate, and a common electrode formed on the second insulating substrate with a second opening pattern.