Where to find and how does the eye movement sensor work?

Question

CCTV

For my mini-project, I need a human eye movement sensor. I have searched the internet and can't find anything. I know what it is! I need to know with the help of the camera at what height in relation to the camera are the human eyes. I ask those who know about this, write where to find (buy) and how to work with such a camera (maybe not a camera, but I doubt that something else will perform such a function).

Answer 1

There is no such sensor. Eye tracking is done through pattern recognition from a conventional (or non-conventional) camera.

Answer 2

There are special eye-trackers, but they recognize the direction of gaze, where exactly in the picture a person is looking. We used such devices for video research. But this is a stationary device that monitors the pupils.
You also need to use a video camera and some machine vision methods to select a face in the frame and calculate the height of their position