Our goal is to realize a system where a laser pointer can be used like a mouse. Such a system realizes more smooth operativity in presentations as well as some human-computer interaction applications such as games. We realized a function to automatically move the mouse cursor to the laser spot on a screen. Restriction on illumination environment was improved using a frequency-demodulation CMOS image sensor. Methods to realize a spot detection and information transmission such as a mouse click without using a synchronous signal were proposed and verified by the experiments. Such asynchronous operations make a signal line to a laser pointer unnecessary.