It’s not the difference in time. It has an IR camera that will basically see two bright dots on a black background. That lets some relatively simple math get you rotation and distance from the bar using the distance between the dots, and pointing position from the absolute position of the dots in the camera’s frame.
The candles thing does work - I’ve tried it before. There are also 3rd party sensor bars you can buy.
It’s not the difference in time. It has an IR camera that will basically see two bright dots on a black background. That lets some relatively simple math get you rotation and distance from the bar using the distance between the dots, and pointing position from the absolute position of the dots in the camera’s frame.
The candles thing does work - I’ve tried it before. There are also 3rd party sensor bars you can buy.