5 ms·

Sweep a physical occluder across the lens, measure abatement?

rootusrootus 7y ago
Maybe the laser also sweeps.
Filligree 7y ago
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.
- sjg007 7y ago
  can't you digitally swipe in the ccd then? just turn off individual detectors accordingly?
  - ukd1 7y ago
    yep, but you'd still not get much useful if each one is maxed out - maybe a little more?
    - DuskStar 7y ago
      And that assumes there's no physical damage to the sensor, too.
bufferoverflow 7y ago
So you want your lens covered 99.9% of the time, just in case someone points a laser at it?
- Terr_ 7y ago
  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.
- CharlesColeman 7y ago
  >> 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 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).
  - AWildC182 7y ago
    Modern systems are Focal Plane Array which is aerospace speak for a typical camera.
AWildC182 7y ago
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.

Maybe the laser also sweeps.

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.

sjg007 7y ago
can't you digitally swipe in the ccd then? just turn off individual detectors accordingly?
- ukd1 7y ago
  yep, but you'd still not get much useful if each one is maxed out - maybe a little more?
  - DuskStar 7y ago
    And that assumes there's no physical damage to the sensor, too.

bufferoverflow 7y ago

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

Terr_ 7y ago
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.
CharlesColeman 7y ago
>> 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 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).
- AWildC182 7y ago
  Modern systems are Focal Plane Array which is aerospace speak for a typical camera.

AWildC182 7y ago

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.