1. A method of detecting at least one object on a road, comprising: simultaneously capturing two depth maps of a current scene by adopting two depth cameras, and then calculating a disparity map of the current scene based on the two depth maps; obtaining, based on the disparity map, a V-disparity image of the current scene by adopting a V-disparity algorithm; detecting an oblique line in the V-disparity image, corresponding to the road in the disparity map, and then removing all of the points in the disparity map, corresponding to the oblique line detected in the V-disparity image, so as to acquire a sub-disparity map excluding the road; detecting plural vertical lines in the V-disparity image, and then extracting, for each of the plural vertical lines, all of the points corresponding to this the vertical line from the sub-disparity map excluding the road, to serve as an object sub-disparity map corresponding to the vertical line; and merging any two rectangular areas of the object sub-disparity maps, whose disparity distance is less than a distance value and whose overlap rate is greater than a threshold value, into a rectangular object area.