1. An optical tracking device comprising: a plurality of light-emitting units correspondingly disposed on a plane of a carrier in geometric distribution, said plurality of light-emitting units providing a plurality of light sources of different colors; a plurality of image tracking units individually being tilted along horizontal axes and vertical axes in order to track said plurality of light sources and capture a plurality of images; an image processing unit connected with said plurality of image tracking units, said plurality of images being subjected to image processing by said image processing unit to obtain light source images corresponding to said plurality of light sources in said image; an analysis unit connected with said image processing unit, said analysis unit analyzing said light source images to obtain positions corresponding to said plurality of light-emitting units and colors corresponding to said plurality of light-emitting units; and a calculation unit connected with said analysis unit and establishing a plurality of three-dimensional coordinates corresponding to said plurality of light-emitting units based on said positions and colors, and said calculation unit further calculating the position of said carrier based on said plurality of three-dimensional coordinates.