• Socsa@sh.itjust.works
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    1 year ago

    The hard part is predicting atmospheric effects to get the focus right. It’s basically impossible without some form of just in time compensation. One idea I’ve seen is that you fire a physical projectile and use that to calibrate the focal point at arbitrary distance, almost like a laser tracer.

    • Dimand@lemmy.world
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      1 year ago

      It’s not easy but you can correct the atmosphere. This is done with guide stars and adaptive optics.

      The bigger challenge is that for intense pulsed lasers, the standard laser profile causes them to self focus in air through nonlinear effects. To overcome this you need to make weird profiles like top hats that are much hard to get just right.

      This is a fundamentally physical limitation that is pretty tricky to overcome.