Question
I'm told that the original Duck Hunt (NES) works fine on all CRT screens, but fails to register successful hits on a plasma or LCD screen. Why is this? Is there a fix for it?
Answer
It is actually a software issue. This question has it almost correct, but it doesn't address the issue of having multiple ducks on the screen and which one you are aimed at.
To understand this part, you have to know about retrace lines.
Retrace lines only exist on CRT type displays that contain cathode ray tubes (typically three). Inside this tube sits an electron gun. To draw a picture, a electron gun shoots an electron beam that interacts with the phosphor coated screen to generate a RGB color. This electron beam sweeps across the screen both horizontally and vertically many times per frame, and the end result is the picture you see.
During this process, the NES or whatever system you have hooked up to your TV knows the exact position of the retrace, and it uses that information, as well as the hit/miss detection in the linked question to determine if you hit a particular duck on the screen.
Why does this not work for LCDs and Plasma? Well, the main reason is simply because those screens behave differently. The pixels in the LCD and plasma are turned on/off rather than relying on interacting with a beam of electrons so a different method to determine where the gun is pointing has to be developed.
Check more discussion of this question.
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