Abstract: The invention relates to a lighting device, which includes a light source, a pattern disc provided with a plurality of pattern sheets, a rotating shaft and a drive mechanism. The rotating shaft passes through the axial center of the pattern disc and is driven to rotate by the drive mechanism to rotate the pattern disc. The pattern sheets are then rotated in turn to a light path of the light emitted by the light source. The lighting device further includes a positioning unit for pattern disc including a Hall plate, a fixing bracket for the Hall plate and a magnet. The Hall plate is mounted on the fixing bracket for the Hall plate, and the magnet is mounted on the pattern disc. The pattern disc is rotated to bring the magnet close to the Hall plate to generate magnetic induction.