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I would like to know if a very bright light will attract an incoming laser guided weapon such as a laser guided missile.

Say for example that a tank has a six-foot pole on the top of it and attached to the end of this pole is a high-voltage carbon arc lamp and it emits light in all directions. I am wondering if the intense light of a carbon arc lamp will outshine the reflecting laser light coming off the surface of the tank and the incoming laser guided missile will steer itself towards the carbon arc lamp.

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Can a very bright light attract an incoming laser guided weapon?

I want to point out that I am not an engineer and I know very little about how laser guided systems work, so I am asking this question simply out of scientific curiosity.

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  • $\begingroup$ it could prevent the missile from detecting the laser mark $\endgroup$
    – jsotola
    Mar 16 at 0:33
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    $\begingroup$ it makes no sense to give a missile the behavior of a moth $\endgroup$
    – jsotola
    Mar 16 at 0:34
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    $\begingroup$ @jsotola It does if you need sun or moon destroying missiles. $\endgroup$
    – DKNguyen
    Mar 16 at 5:12
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    $\begingroup$ @jsotola isn't that the definition of a heat seeking missile? and isn't the counter measure for those a really hot flare for them to lock on to instead of the hot exhaust of an engine? $\endgroup$
    – Forward Ed
    Mar 17 at 0:33

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No. It might blind it but it would not attract it.

Laser guided weapons aren't just laser versions of heat-seeking weapons. You would modulate the targeting laser so that it could be differentiated even in the presence of another light of the same wavelength.

And if the missile has optical filters (which it will) they will just prevent most of the light at irrelevant wavelengths from ever getting to the sensor to saturate it. That would mean that your arc light would have to emit enough light specifically at the pass-gap and to saturate the sensor.

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    $\begingroup$ What you said makes sense. This now makes me wonder if the brightness of a carbon arc lamp would make it difficult for the person pointing the laser at the tank to clearly see the tank and to keep the laser pointed at it. For example, the person's eye may have trouble staying focused due to the bright light. $\endgroup$
    – user57467
    Mar 15 at 21:24
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    $\begingroup$ @Martheen Sending bright monochromatic focused light is becoming a thing. $\endgroup$ Mar 16 at 7:39
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    $\begingroup$ @Russell's approach could dazzle the sensor as a direct beam will be far brighter than the reflection off the target, even making the beam slightly divergent and aiming/delivering photons at a fast-moving missile is far easier than aiming bullets at it. "Far brighter" means the modulation of the targetting laser is lost in the noise, or the detector is saturated and reading max value for all pixels at all times. I can't instantly find what wavelengths are used for guidance but it will be a small list $\endgroup$
    – Chris H
    Mar 16 at 10:42
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    $\begingroup$ There's a lot of history here, and yes early optical guided missiles might have been distracted this way. Since the advent of solid-state imaging chips, things like anti-tank missiles use image processing for the final approach so they can precisely hit points like the turret-body interface. $\endgroup$ Mar 16 at 15:20
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    $\begingroup$ @user57467 it's really worth going for a beam or a narrow cone, for a few reasons - to avoid making your position even more obvious, to avoid dazzling your own/comrades own optics, and to put the light in the right place. A 1° cone is pretty broad at km ranges, but about 40,000 times more efficient at illuminating the target with the same brightness $\endgroup$
    – Chris H
    Mar 17 at 17:36
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Probably not.

Look, anything is possible. You could throw some rocks at a keyboard, and have it open SE, log in, and post an proof of trisection.

It ain't real likely.

Laser guided weapons usually have some specific frequency they're looking for. Then, on top of that, the laser is pulsed as an identifier (think of it spelling four letters in Morse code on a loop — not how it works, but a good analogy).

To misguide your missile, you're looking at the narrow band of light you're looking for coming off the arc lamp, then flickering in a way that duplicates the "Morse code" the weapon is looking for. That's... unlikely.

More plausible is that you can put out so much light that you blind the missile, and it doesn't hit anything. Of course, the more traditional way to do this is with another laser that you shine back at it - much lower power cost; far fewer friendly effects.

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    $\begingroup$ So, you are saying that the carbon arc lamp would have to pulsed at the same frequency/modulation of the tracking laser. That's interesting, yet I imagine the frequency/modulation of a laser would be pretty high and I wonder if a carbon arc lamp would be capable of producing such a high frequency. It's something I'll have to research. $\endgroup$
    – user57467
    Mar 16 at 23:14
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    $\begingroup$ @user57467 Not just frequency but the same "code". In combat it's possible to simultaneously target multiple targets with multiple lasers and launch multiple bombs and none of the bombs will go to the wrong target. It's like, the laser is spelling "LOOK-I_AM LAZER:NUMBER=22" and the bomb is looking for a laser signal that is broadcasting "LOOK-I_AM LAZER:NUMBER=22" and ignoring the one that says "I_AM_CHINESE-LASER-SYSTEM-NUMBER-513". That's not exactly the codes used in the real world but you get the idea. $\endgroup$
    – slebetman
    Mar 17 at 7:38

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