EVERYDAY OBJECTS AS LASER BEAM BLOCKERS
Depending on the wavelength and power, blocking a laser beam could be as simple as placing an object in its path. For instance, certain barcode scanners, laser pointers and LIDAR technology literally depend on everyday objects blocking laser light.
LIDAR is basically the laser equivalent of a bat using echo localization to map out its surroundings. Short bursts of laser light are emitted in all directions, and by measuring the time it took for the light to bounce off of objects and back, the distance can be calculated.
Historically, LIDAR was used mainly for industrial and scientific purposes, but as prices have gone down, the use-cases have diversified. Self-driving cars and even some smartphones have incorporated lasers to better account for the 3D nature of our world.
All this to say that some lasers can be blocked rather easily. If your setup only uses low‑power lasers, simple beam shutters may be all you need.