The screen is a standard CRT. The game basically alternates showing left and right images and sends the signal to the glasses to blank out the correct eye so you only see one image at a time. So, the 3D effect only works on a CRT because it is specifically timed to the refresh rate that is standard to these monitors. Luckily, the glasses just have three wires (left eye, right eye, and neutral). So, it is simple enough that the glasses from Sega work fine for this cabinet. It is the same tech, just a slightly different shape.