A device for measuring a gap and a step between two panels is disclosed. The device includes a laser radiating unit for emitting laser beam over a first panel and a second panel and in a first linear pattern across a gap between a first panel and a second panel. The device further includes a lighting unit for emitting a non-laser light beam over a first panel and a second panel and in a second linear pattern overlapping the first pattern across the gap between the first and the second panel. The system further comprises a camera for capturing images of the first linear pattern of laser and the second linear pattern of non-laser light projected over the first panel and the second panel. The system analyzes at least one image captured from the camera and estimates a width of the gap between the first and second panels.