How does Rambo Arcade's light gun work on an LCD screen?
As we all know by now, light gun games that worked on a CRT TV do not work on a plasma or LCD screen. However, in recent years an arcade game based on Rambo was released:
As you can see in that video, there appears a working light gun, on a modern LCD screen. There's also no tracking/pointer on the screen that you see with Wii shooters.
How does this light gun work on a non-CRT display?
Best Answer
Old CRT light guns worked by blanking the screen very briefly and then the gun detects bright light. Some worked by displaying bright regions sequentially. This happened quickly enough that the user wasn't aware.
CRTs fire a beam across the screen one line at a time starting from a corner, drawing horizontally (not unlike a typewriter filling a page). The old Nintendo method was to blank the screen when you pulled the trigger and then time how long it took for the gun to see the bright line being drawn.
Devices like the Wii, the xbone, etc now use two infrared light emitters separated by a fixed distance and the "light gun"/wiimote has an optical sensor that measures the point separation between these two sources. With the perceived separation, the known fixed distance, and some extra accelerometer data, the computer can triangulate the pointer position.
Note that a non-crt screen can still use the older blank screen method, just not the scanline timing method, but I expect that the Rambo game uses the infrared method.
Pictures about "How does Rambo Arcade's light gun work on an LCD screen?"
How do you make a light gun work on LCD?
Currently, to use a light gun on an LCD screen you need an infrared emitter where the screen is. Then you need to calibrate for your seating position, and then recalibrate every time you move.Will a light gun work on a flat screen TV?
You point the gun at the screen and pull the trigger, and if you hit the target on the screen, the target explodes. To create this effect, the gun contains a photodiode (or a phototransistor) in the barrel. The photodiode is able to sense light coming from the screen. The gun also contains a trigger switch.Rambo Arcade Gameplay - Full Playthrough
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