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How does the laser gun work?

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amazon10x

Member
Joined
Feb 15, 2003
Location
College Park, MD
Ok, I would like to know how those laser guns work (e.g. The orange gun that was used for Duck Hunt on NES). A link would be fine if thats all you've got.
 

cack01

Member
Joined
Mar 7, 2002
Location
San diego or UC Davis
They are actually called light guns. When you shoot, the TV screen refreshes, and there is a line drawn across the screen when the refresh happens. Remember this is at 60hz (depending on where you live) so its not easy to see. Anyway, you're pointing your gun at the screen, and the gun is essentially a light sensor. When the part of the screen which the gun is pointing at gets drawn over with white, the sensor in the gun detects it and then tells the game "I can see white now, I'm pointing at the part of the screen you've just drawn". At this point the game can work out how far down the screen it has drawn, and how far along the current line, which gives a pretty accurate position of where the gun is pointing. At this point it no longer needs to flood the screen in white and can carry on drawing the game scene for the rest of the frame.

The game then draws a "splat" mark or whatever on the screen where the gun is pointed and kills off any baddie or whatever at that position on the screen. You think you've shot them, when it's actually the screen firing at you.


Edited with better info and to make sense.
 
Last edited:

cack01

Member
Joined
Mar 7, 2002
Location
San diego or UC Davis
here is a pic of the inside of one of my guns. Its a very simple circuit. The solenoid on top is used for recoil.
 

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TommyHolly

Member
Joined
Apr 30, 2003
Location
Chicago
Also, it confuses the gun when you set the brightness all the up on your TV into thinking you hit your taget becuase it registers light.

When you usually hit something, it paints light at a certain spot, but when you turn the brightness up...EVERYTHING has light and it thinks you hit your target.
 

SniperXX

Member
Joined
Jul 24, 2002
Location
Folding in Diamond Bar
cack01- Nice description and dead on correct. You explained it better when I tryed explaining it to my friend the first time, lol. Also, thats an interresting pic, thanks for posting.
 
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amazon10x

Member
Joined
Feb 15, 2003
Location
College Park, MD
Hmm, thanks for explaining that cack, The other day I was using one and I thought, "How do these things work?". Now it all makes sense, also, thanks for the pic.
 

Robrules18

Member
Joined
Jul 20, 2003
Location
Peoria, IL
Tommy I can't resist when you said that, heres some funny parodies of those GIjoe learning things after the episode, WARNING: foul language but no suggestive themes.

http://www.ebaumsworld.com/gijoe.html

my fave is the 2nd one from the bottom or the "penultimate" one there i used my big word of the day.
 

BigSmokey

Member
Joined
Oct 21, 2003
Location
Bloomington IL
jacheatamobits said:
so could you go to the arcade, and rig up a battery powered LED on the front of the gun, and like, totaly destroy any shooting game there is?

btw Silent ScopeII is still my fav.

I would like to know about this. Do the arcade guns work the same?
 

cack01

Member
Joined
Mar 7, 2002
Location
San diego or UC Davis
Yes they work the same.

I doubt it would work. The gun is looking for the exact moment it sees light (white), it then compares it to where the game drew the object. So basically its a timeing thing. I think it would just really mess with the games head. But I could be wrong though.