Position tracking sensor of optical mouse and method of controlling the same

A method of controlling a position tracking sensor of an optical pointing device, the method comprising the steps of:

• a) turning on a light source of the optical pointing device to light up a worktable;
• b) detecting an image of the worktable;
• c) calculating a movement value from the detected image;
• and
• d) turning off the light source of the optical pointing device when it is determined that the optical pointing device is spaced apart from the worktable using the detected image wherein the step d) includes:
• a first sensing step of determining whether the optical pointing device is spaced apart from the worktable by turning off the light source of the optical pointing device to measure light intensity of the detected image in an active state where the light source of the optical pointing device is maintained in an On state during most of time and the movement value is calculated;
• and
• a converting step of converting the active state into an inactive state, where the light source of the optical pointing device is maintained in an Off state during most of time and the light source of the optical pointing device is intermittently turned on to determine whether the optical pointing device moves or not, when it is determined that the optical pointing device is spaced apart from the worktable in the first sensing step.