It's maybe more along the lines of some of the mindfulness protocols, which are a form of meditation.

There's one where you are at rest and slowly shift the focus of your gaze from near to middle distance to far away, and back.

It's supposed to be a grounding exercise to bring your mind back to a state of rest and just observing.

Blanking out is afaik the exact opposite of "mindfulness".

This is almost exactly like Transcendental Meditation, even down the to the length of time of ~20 minutes.