Each of the second input line IL2, the fourth input line IL4, and the sixth input line IL6 may be electrically connected to a corresponding one of the first additional vertical connection line DV1, the second additional vertical connection line DV2, and the third additional vertical connection line DV3 via the second contact holes CNT2. Each of the first horizontal connection line DH1, the second horizontal connection line DH2, and the third horizontal connection line DH3 may be electrically connected to a corresponding one of the first additional vertical connection line DV1, the second additional vertical connection line DV2, and the third additional vertical connection line DV3 via a first connecting contact hole DH-CNT1 at one end thereof. Each of the first horizontal connection line DH1, the second horizontal connection line DH2, and the third horizontal connection line DH3 may be electrically connected to a corresponding one of the first vertical connection line DV1′, the second vertical connection line DV2′, and the third vertical connection line DV3′ via a second connecting contact hole DH-CNT2 at an opposite end thereof. Each of the first vertical connection line DV1′, the second vertical connection line DV2′, and the third vertical connection line DV3′ may be integral with a corresponding one of the second data line DL2, the fourth data line DL4, and the sixth data line DL6.