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Comment by serioussecurity | Hacker News Reader

Sweep a physical occluder across the lens, measure abatement?

You can do that, but a more powerful laser will max out the readings even at maximum occlusion, and it's another mechanical device which can fail.

It's a game of cat and mouse.

can't you digitally swipe in the ccd then? just turn off individual detectors accordingly?

yep, but you'd still not get much useful if each one is maxed out - maybe a little more?

And that assumes there's no physical damage to the sensor, too.

Multiple lasers across multiple ships performing random amplitude modulation. The missile would have to somehow spot attenuate multiple sources at variable intensities.

At the end of the day, everything with sensors is an arms race. We've actually seen this evolution before with the early spinning mirror IR missiles and those glass disco balls on helicopters.

So you want your lens covered 99.9% of the time, just in case someone points a laser at it?

Who says you're limited to one? For that matter, if you're just trying to find the direction of the beam, why bother with "good sensor" at all?

Set up a bunch of not-quite-parallel tubes with simple and durable light-sensors in the "deep" end, and whichever sensor measures the highest must be pointed at the light-source.

>> Sweep a physical occluder across the lens, measure abatement?

> So you want your lens covered 99.9% of the time, just in case someone points a laser at it?

Don't some missile seekers already work that way?

https://www.ausairpower.net/TE-Sidewinder-94.html:

> The Sidewinder's seeker used an ingeniously clever optical arrangement, with a Cassegrainian mirror fitted with a tilted secondary mirror. The secondary mirror rotated in unison with a reticle, projecting the whole instantaneous field of view of the mirror through the reticle onto a filter/detector assembly. Because the mirror secondary was tilted, rotating it about the missile's axis swept the cone of the mirror's field of view about the missile's axis in a fashion analogous to a conical scanning radar seeker (see diagram).

Modern systems are Focal Plane Array which is aerospace speak for a typical camera.

Maybe the laser also sweeps.

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