how to use a laser

Hi houzd
The laser you are referring to is a dot projector used to create dot patterns on surfaces that have no texture or have repeating patterns. The dot pattern gives each part of the scene a unique appearance, making it easier to find corresponding points in the two images, and therefore more accurately calculate disparity.
The depth/distance to a point is calculated the same with or without the laser dot projector - through disparity.

Thanks,
Jaka