Eli5: how does a “digital infinite mirror” work?

305 views

A physical one it’s just light bouncing back and forth, but a digital one (when sharing screen for example) the computer has to create the image

Does it have limited number of loops or something?

In: 3

3 Answers

Anonymous 0 Comments

They’re pretty similar. You can think of a mirror as a screen showing whatever is in front of it. So if you put two mirrors facing each other, the first one has a reflection of itself in front of it, so it shows itself on itself. Then it shows itself showing itself showing itself. Then it shows itself showing itself showing itself showing… and so on.

Similar for a share screen situation, the meeting window is showing your screen, so your screen is now showing the meeting window showing your screen, then your screen is showing the meeting window showing your screen showing the meeting window… and so on (again).

Now, the screen image is represented as a finite number of pixels, and shrinks each time through the loop because you’re fitting a copy of your whole screen into a window that’s smaller than your screen. At each round of shrinking, you’re reducing the number of pixels the copy of the screen takes up, so you’re resampling the pixels to fit that smaller size and losing some information in the process. Eventually you get to the point where the copy of the screen takes up a single pixel, and gets copied for further iterations as such. On the other hand, for a mirror, the image gets smaller and smaller as it progressively fades into the distance (where distance here is the space between the mirrors multiplied by the number of times the image has bounced back and forth), but theoretically with a perfect mirror you wouldn’t lose any information and could “zoom in” to counteract that, at least until you get to the scale where quantum nonsense messes everything up.

You are viewing 1 out of 3 answers, click here to view all answers.