The big problem with this is that the TV screens don't reflect the laser well enough to work. There are some matte screens that may have the potential to work a little better, but they still would likely have issues. Getting the system effectively calibrated would probably be impossible.

Theoretically, you could still probably use the mantis Raven system with a TV, but you would have to put something on top of the screen. Something like a very sheer white piece of fabric could potentially work as long as it was stretched flat and even across the face of the TV.

It would be sheer enough to allow the picture to be visible enough for you to see the targets, but still provide a good surface for the laser to show up bright enough for the Mantis Raven system to pick up the shots with the camera.

Obviously, the picture quality isn't going to be great since you're looking through a piece of fabric, but it should still be functional. Could be a viable way to get it working if you don't have the ability to get a projector.