As others have mentioned, there's a huge difference between the old CRT monitors and today's LED/plasma technologym requiring a potentially different technique … with, therefore, potentially different outcomes — although, given the constant speed of light, it might actually be easier today, who knows?

But, if it can be (reliably and cost-effectively) done in a given situation, the solution to that is simply a mathematical calculation of the timing differences between data arrival which, given knowledge of the space through which they travel can be reasonably relied upon.

To get some idea of how these things are done, take a look at:

Impulse Response reverberation modelling: Play some sounds (pink/white/brown noise), in a space and record them. Add the inverted phase of those frequencies to the recording to cancel out the original sounds and what you are left with is the audio signature of the space (through which you can now pump any sound you like and get back the same response as if you were standing in it). If you have an imperfect recording of a conversation between people in that space, you simply interpolate the missing material into the gaps (think about how RAID systems recreate missing data for a crude idea of this principal).

3D printer manufacturers getting extremely concerned about the potential for industrial espionage (using IR reverb modelling) to rip off their designs: Stick a microphone next to the room the 3D printer is in (or a camera across the street), bounce some sound (or light) off the wall and model the space. Place an order for an item with the company and do the same whilst the printer is active. You can now calculate the printer's physical movements in that space and, from that, reverse engineer it's physical properties. Given the physical model and the kinetic signature calculated from the audio, you can recreate its function ... and go and build that very same model of 3D printer for yourself.

For an appreciation of how Maths can be applied to the seemingly most unmathematical of phenomena, computational linguistics is a good (if very dull) place to start — an awful lot of time is spent calculating the cosine of Thursday and integrating the curve of ‘large’ for a given set of subject/object referents, for instance 😉 (and it can involve not a little Fuzzy Set Theory too)

It’s not simple as such, but it’s not science fiction either … just Maths.