lol... I wondered that too, but never thought of researching it...
* WDZ does some Googling...
quote:
How does the Nintendo Duck Hunt work?
A: The Nintendo Zapper Gun, also remembered fondly as the Duck Hunt gun, isn't really a gun, it's a photoelectric sensor that detects the light given off by the TV. When you pull the trigger on the gun, the Nintendo system tells the TV to momentarily replace the ducks with white rectangles. If you go back and play the game again, you'll notice that the screen flashes momentarily when you pull the trigger. If the gun happened to be pointing at a duck at that specific moment, the sensor in the gun transmits to the NES that it had a white rectangle in its field of view, which the game registers as a hit. In the oldest models of the gun, you could simply point the gun at a light bulb and make a direct hit every time. Later versions of the gun corrected the problem by having the screen flash completely black, then with white triangles, then black again. The gun was programmed to recognize "black, white, black" as a direct hit. This system used by the Zapper, which is known as a light gun, was also used in arcade games.
Cool!
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