The patent says that the gun receives "invisible light", rather than transmitting it. If the patent is referring to the same type of system as this Duck Hunt de

The patent says that the gun receives "invisible light", rather than transmitting it. If the patent is referring to the same type of system as this Duck Hunt device (it's for a similar clay-shooting game), the purpose of the capacitor is to transmit a signal to the game device to tell it a shot has been fired. The gun wouldn't have a flashbulb but a photodiode. When the trigger is squeezed, if the photodiode is receiving the right frequency of flashing light, the gun will transmit the signal as a hit. This is similar to how I understand the NES Zapper to work. Caveat: I don't know enough about electronics to look at the photos in the attached article to confirm what I'm saying, but I am fairly confident that I'm reading the patent correctly. (It refers to the gun as "light-receiving" many times.) ETA: If this is how the non-functioning Duck Hunt works, it's possible that it isn't the gun that's broken but the infrared emitter in the projector. ETA again: Found a YouTube video where someone has this device and points it at the camera and shoots. There's a visible light flash. https://www.youtube.com/watch?v=Vsh-WTZFX58 https://www.youtube.com/watch?v=Vsh-WTZFX58 So it's not the same as the patent. The projector itself has a sensor on it, as mentioned in the article, and the light emitted by the gun flashes in a predetermined pattern.