Hey IsaiahQ, LCD screens are usually LCD panels mounted onto a piece of acrylic.
The LCD screens have an aluminum backing on them, and (in some cases) some film layers which would need to be removed to enable the camera to see ‘through’ the acrylic and LCD panel.
The LCD screen needs the acrylic so that the 2x Fluro lights can illuminate the LCD screen evenly. We just use the FTIR setup to flood the acrylic with IR light as well, and - because we’ve removed the backing of the LCD monitor - our rear mounted IR camera can detect touch inputs through the acrylic/LCD module on to the surface of the screen itself.
There are many examples of these type of setups on various threads throughout the forums.
I’ve added a picture from one example (BlaxWan’s website) showing the camera and dismantled LCD screen.
In the picture below, the aluminum backing (at the top of the picture - with the white layer) has been detached and moved to the side to allow the camera to see ‘through’ the acrylic/LCD module.
Also check out nima’s LCD FTIR thread here
Hope this helps you understand the process a little more…