A display device is disclosed, which includes a display panel and a detection circuit. The display panel has pixels configured to display an image. The pixels include display and photo sensing pixels that are arranged in sensing channels. Each display and photo sensing pixel includes a display region and a photo sensing region. The display region emits light. The photo sensing region detects the light emitted by the display region and reflected from a biometric object and to convert the reflected light into photo detection signals. The detection circuit has differential signal processing circuitries that are coupled to the photo sensing regions of the display and photo sensing pixels. Each differential signal processing circuitry performs a differential operation on the photo detection signals of adjacent two of the sensing channels to generate a difference signal that is used to construct a biometric pattern corresponding to the biometric object.