Optical mouse that detects working surface using code included in illuminated light and control method thereof

A method of controlling an optical pointing device, comprising:

• an illumination step that turns on or off an illumination unit to illuminate light on a work surface during a calculation period;
• a calculation step that detects an image on the working surface to calculate a movement value, and outputs movement information during the calculation period, intermittently outputting a code generation signal to determine whether or not the optical pointing device is separated from the working surface during the determination step;
• a code generation step that turns on or off the illumination unit to generate light in a predetermined code in response to a code signal during a determination period, wherein the code signal repetitively turns on or off the illumination unit depending on a certain code value during the determination period;
• a determination step that outputs the code signal to determine whether or not the optical pointing device is separated from the working surface in response to the code generation signal, detects light output from the illumination unit to analyze a code included in the light and determines whether the code included in the light matches the predetermined code, to thus determine whether or not the optical pointing device is separated from the working surface and outputs a determination signal depending on the determination result during the determination period;
• and
• a glaring prevention step that turns off the illumination unit when the optical pointing device is separated from the working surface in response to the determination signal,
• wherein the determination period does not overlap with the calculation period, and the light generated during the determination period is different from the light illuminated during the calculation period.