Sensor Bar
The Sensor bar is the component for the Wii that sends infrared signals to the Wiimote.
The sensor in the Wiimote is a PixArt optical sensor that determines where the Wiimote is pointing. Unlike a light gun that senses light from a television screen, the Wii Remote senses light from the console's Sensor Bar (RVL-014), which allows consistent usage not influenced by the screen used. The Sensor Bar is about 20 cm (7.9 in) long and has ten infrared LEDs, five at each end of the bar.[46] The LEDs furthest from the center are pointed slightly outwards, the LEDs closest to the center are pointed slightly inwards, while the rest are pointed straight forward. The Sensor Bar's cable is 353 cm (11 ft 7 in) in length. The bar may be placed above or below the television, centered horizontally, in line with the front of the television or the front of the surface the television is placed on. The Remote should be pointed approximately towards the Sensor Bar; precise pointing is not necessary so long as it is within the limited viewing angle of the Wii Remote.
Due to the sensor being IR-based, it can detect any IR signal as input, this include candles.