In a method of driving a display panel, a gate signal is outputted to the display panel based on a first control signal. The imaging lens further includes a second lens group that includes a negative lens having a convex surface directed toward an image plane and a third lens group that includes a positive lens, where the first lens group, the second lens group, and the third lens groups are sequentially arranged from the object side. The method of training grapevines may also comprise defining a plurality of renewal canes.