Old lightguns used CRT monitors to work, and are not compatible with modern systems anymore.

I've com up with an idea and would like to know if it's doable and what problems there could be.

The idea is to stick a Infrared Laser inside the gun, and fit a webcam right underneath the laser.

When you shoot the webcam sees the monitor (brighter than the surrounding) and sees a bright spot from the laser where you shot. With some graphic modules it could straighten the image and calculate where you have shot. With the modern quad-core raspberries it might be powerfull enough to calculate this fast enough and send the coordinates to the console/pc.

Would it be possible?


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    \$\begingroup\$ I'd rather just use the same tech they use in a Wiimote. \$\endgroup\$ Sep 15, 2015 at 14:58
  • \$\begingroup\$ Place two colored LEDs on the guns barrel and let the cam to see it. Then by calculating the line going through the two points you can find the lien in 3D space. Also you might need to disambiguate the solution either using some kind of orientation sensor on the gun, or by adding some more LEDs. \$\endgroup\$
    – Eugene Sh.
    Sep 15, 2015 at 14:58
  • \$\begingroup\$ At first glance, this seems like to be a feasible idea. Why not start mocking this system up and see what you find out? One thing that might help your software would be to put some fiducial elements in the corners of the screen - either as part of the displayed image or as corner markers that are applied to the external frame on the monitor. \$\endgroup\$ Sep 15, 2015 at 15:01
  • \$\begingroup\$ @EugeneSh. wouldnt this need to have a extremely high definition in order to be somewhat precise? Also, i hardly understand how 2 points can give you a precise position in space. One webcam sees 2 points, but does that define orientation? \$\endgroup\$ Sep 15, 2015 at 15:05
  • \$\begingroup\$ @sharkyenergy The precision can be estimated, you can do it if you want :) Also see the note on disambiguation in my comment. Actually after some though I conclude it is not the best and easiest method to achieve this, so take it to a limited extent :) Mounting camera in the gun and injecting some markers in the picture would be the easiest solution from the hardware point of view. \$\endgroup\$
    – Eugene Sh.
    Sep 15, 2015 at 15:08


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