In a related area I have been developing an invention I call a laser cage. the idea is to make a cage of laser beams going back and forth to cover an entire surface so it becomes like a force field. Each edge of the cage would be made of perfect mirror material. This is so reflective that an optic signal could go across the Atlantic in a tube of it without needing amplification.
One interesting part is as you feed laser energy into it the amount of energy in it keeps increasing until the amount lost from absorption by the mirrors equals the amount being fed in from the laser. So if the mirrors for example lose 1/10,000 of the beam's power in a full circuit then the total strength of the beam on initial contact by something would be 10,000 times the strength of the laser. If it was for example a 50KW off the shelf laser then it should have a strength of 500 Megawatts.
This would be only on the initial contact and might be good for something like a projectile. The cage can be designed so there are several layers of laser energy with a gap between them, though the light makes a trip though all these mirrors.
If it hits a projectile for example then by the time it reaches the next layer the energy in the cage has ramped up again to say 10,000 times the beam power. It can be zapped as many times as there are layers.
I was discussing this as a way to protect satellites, etc from debris but it depends a lot of the size of the micrometeorites and 1 cm in size may be an upper limit for destroying these. Also of course the mirrors themselves have to be protected.
Anyone trying to walk through it would get a nasty zap.