Patent ID: 8044936
Filing Date: 2011-10-25
Classification: G06F,Y02D

Abstract:
1. An optical navigation device comprising: a light source that irradiates light; an image sensor that collects incident light to obtain an image and outputs the image; and a controller that performs: a compensation mode that turns OFF the light source and receives a plurality of images as a plurality of compensation images when the optical navigation device is not separated and then obtains a minimum luminous intensity from luminous intensities of the plurality of compensation images, a calculation mode that turns ON the light source and receives the image to calculate a movement value, and then determines whether the optical navigation device is moved on the basis of the movement value, a sleeping mode that turns OFF the light source and stops an operation of the image sensor, and a detection mode that turns OFF the light source and receives the image as a detection image, and then compares the luminous intensity of the detection image with the minimum luminous intensity and determine that the optical navigation device is not separated from the work surface when the luminous intensity of the detection image is substantially equal to the minimum luminous intensity of the plurality of compensation images wherein the controller performs the calculation mode when the optical navigation device is moved and not separated from the work surface, performs the sleeping mode when not moved or separated from the work surface, and periodically performs the detection mode during the calculation mode and the sleeping mode, and wherein the compensation mode is performed at an initial stage of the device operation.