Laser Vision on Killer Androids: How would it actually work?

So, I'm designing some new android characters and I've run into a logical issue I've noticed before but never addressed because most of my other characters with laser eyes are either gods or have supernatural powers. That issue being, how does a killer robot shoot lasers from its eyes and yet still manage to use them for seeing with? The emitter for the beam would be right behind the eye's lens and render it useless as an eye. The closest workaround I can think of is for the lasers to come from ports that open up near the eyes, but for some insane reason my brain insists on being awkward and trying to do the 'classic' laser vision that killer robots tend to have.

Yes, this is entirely for the sake of Rule of Cool, seeing as how my android characters have limbs that are capable of transforming into giant Wave Motion Guns and energy swords. I figure laser vision would come in handy for quick target acquisition and intercepting missiles, stuff like that. Anyway the why of it isn't important, so just concentrate on the how.

These are all the possible justifications I can come up with off the top of my head:

• The lasers don't actually fire from the eyes, but from concealable ports close to the eyes instead. As I said above, this kind of defeats the purpose of giving them laser vision to begin with. It isn't laser vision if it doesn't actually shoot from the eyes dammit!

• The emitter for the laser vision is entirely contained within the iris instead of taking up the inside of the eye. Only I cant see how I'd fit the energy cells for the laser vision into such a small space, even with the extremely high technology base of the setting. If it were just a low energy laser this might work, but I kinda want it to be able to blow holes in battleships. Again, Rule of Cool. Focus on the how.

• The laser fires from a holographic array projected just in front of the eye. I just don't have a clue how this would actually work at all. If it were a magic laser then it wouldn't be a problem, but I can't see how the energy from inside the android would be projected into a holographic array outside the android.

• The inside of the eye is entirely taken up by the parts for the laser, leaving the actual 'seeing' part to a lens mechanism contained in the iris. So, the reverse of the second idea. Problem here is, this would result in having crap vision (the androids are supposed to be able to detect any wavelength of light and see for literally miles with perfect accuracy.) Plus, a lens needs a backdrop for the image to be projected onto, and with this setup there would be a great big hole through the middle where the laser fires from.

Now, the technology base of the setting is extremely high as I mentioned, and the character who makes these androids is literally smarter than God. Problem is, even with said character's ridiculous level of superintelligence, I still need to be able to provide a plausible explanation for the technology (hell, even a plausible Technobabble explanation would suffice), as science is not magic and doesn't benefit from being inscrutable so long as it's internally consistent. But if anyone can give me something which is at least in the ball park of plausibility, then I can probably work with it.

So...I might spend a few thousand words just poking holes into that general concept , but instead here's an idea:

The laser hardware and the eye hardware can be switched out by rotating the eyeball.

....o....
../.I.\..
..|—-|..
..\.../..

That bit of terrible ASCII fail would be the eye's internals. The "o" is the lens, the "I" the visual apparatus, the '—-' represents the laser. For firing, the eye rotates 90 degrees, bringing the laser aperture in line with the lens.

Your robot wouldn't be able to see and use the laser at the same time, which could make for an interesting weakness and provide a cool "uh oh, its eyes just went click, brace for hot lasery doom" effect.

You could use a beam splitter. Since the light coming out wouldn't interfere with the light coming in (interference only happen under very specific circumstances), you could shoot lasers and see at the same time. The only problem is that 50% of the light is lost in both directions. In particular, you'd need something to absorb the laser's energy without shining it back into the camera.

EDIT : I'm thinking of something like this◊.

The most practical set-up would probably be coaxial camera and laser (as in coaxial gun, not actually coaxial).

edited 3rd Mar '16 3:56:41 PM by Aetol

That's a pretty cool idea there. Never considered rotating the eye. Hmmm... I think I'll definitely use that for the low-end military androids, as the whole 'oh shit, it's eyes just shifted!' thing goes great with generic killbots. But the particular characters I'm working on are supposed to be so far beyond the cutting edge of technology that they render everything else cartoonishly obsolete, and the most advanced one is able to fight an entire battlefleet on her own and go toe-to-toe with actual gods (yeah, it's kind of a thing in my universe that pretty much everybody of note is Purposely Overpowered and the only weaknesses characters tend to have is that someone else just has more raw power than they do. Half the cast are gods, and the closest thing to a protagonist is the actual embodiment of conceptual Death. It's a weird story.)

Would a beam splitter work if the laser in question was actually a Cryo-Beam or a Lightning Ray? I was using laser vision as a generic term for 'shoots energy beams from the eyes', where 'energy' is short for 'whatever would be cool to fire from one's eyeballs'. So I'm thinking it probably wouldn't work in those instances.

It definitely wouldn't work with anything other than light, sorry. Even a laser is pushing it, since the beam splitter would likely be heated and damaged.

I think the "beam center, camera around" setup could work. And with clever optics trickery, it might be possible to not have a big hole in the middle of the image.

edited 3rd Mar '16 4:39:47 PM by Aetol

Hmmm. you mean like having the iris actually be a compound eye made of multiple tiny lenses?

The more I think about it, the more I like the 'holographic projector array' idea. It would allow the android to both see and shoot eye beams, and it's suitably OTT that it fits the level of technological advancement I'm going for. It's just that the whole idea of the beam array being 1: nonphysical and 2: located outside the android's body is like a brick wall.

Okay, I'm going to try to get this one to work. First thing that I can think of is that the iris acts as both the projector for the firing array and a superconducting capacitor to build the energy to fire it. I can handwave the implausibility due to the superintelligence of the android's creator (after all, if Tony Stark can build a portable fusion reactor IN A CAVE! WITH A BOX OF SCRAPS!, then I think I can swing a few made-up super-alloys and such.) The holo array itself would be kind of like the Omni-Tool from Mass Effect, made up of force fields or something. As for how the energy charge gets from the capacitor to the firing array.... come to think of it, there would need to be a connection between the projectors on the iris and the holographic array itself in order for it to be projected at all.

Oh fuck it, the energy just arcs from the capacitor to the array and builds up into an energy ball which is then fired like a mini Wave-Motion Gun. There. This at least halfway justifiable? I'm sure Star Trek has technobabbled its way out of dumber situations.

Though how I can justify a Cryo-Beam with this setup... actually, just WTF is a Cryo-Beam anyway? I've never really given it much thought, but coldness isn't actually a type of energy at all.

It's possible to cool individual atoms down by hitting them just right with a laser. Doing it on a macro scale is...well, it's pretty much Clarke's Third Law territory.

Still, that's the technobabble most "freeze rays" that actually bother to give any explanation at all go with.

Ah, so it is justifiable. Though probably not in my case, as I've gone down the same kind of tech tree as Wave-Motion Tuning Fork, so an actual laser is pretty much out now.

Okay, screw it. Literally Magic Robot. The android is powered by a solidified chunk of mana which is attuned to elemental water, which provides the nonsensical freezing energy for the Cryo-Beam.

Actually, now that I think of it, that's kind of an awesome idea. Magic does exist in the setting, and this way I get a free handwave whenever I run into a situation where my superintelligent character creates technology I'd never have a hope in hell of understanding. It's a lazy solution, but I'm a pretty lazy guy. Plus, Magitek is awesome.

If you're wondering why I insist on having a Cryo-Beam, it's just that I barely have any characters who Kill It with Ice, so I wanted to make one with it as their speciality. And I did get a workable justification for 'standard' laser vision on generic killbots, so I'd call that a win.

edited 3rd Mar '16 5:51:14 PM by OmegaKross

You know, you don't have to have Kill It with Ice. On the contrary, if shoehorn in a trope that doesn't quite fit, it is more likely to stand out and might make your work look like a Cliché Storm.

That being said, I second the Magitek with futuristic aesthetics idea.

edited 3rd Mar '16 6:04:38 PM by Aetol

It already is a Cliché Storm. I'm currently in the process of trying to write up a timeline of events and themes for the entire story just so I can figure out what I should cut out (I've not actually written up a good chunk of the plot I've thought up despite it being in my head for most of the past decade or so. You can see how it might get a little overblown.) But yeah, super-advanced Magitek androids who fight gods is one of the better ideas I've had for a while.

Huh, a bit late. I was going to suggest LIDAR. Think radar or sonar, only instead of bouncing radio or sound, respectively, the "eyes" are paired emitters for laser rangefinders that scan through the field of vision very rapidly.

A high-power mode would enable them to see at extreme ranges—or, conversely, burn holes in targets at closer ranges.

You can't see and attack at the same time though. And looking at someone will reveal your position.

Also a good idea. I've already decided on Magical-Holographic-Cryo-Wave-Motion-Gun-Eyes, but I can probably use that for standard military robots which aren't as OTT as giant killbots.

That takes us into questions reliant on technical details. In short, if the laser module can rapidly switch between high-power and low-power, or if both eyes can operate independently, there is no reason "zap while scan" can't be done. The moment the scanning laser passes over the target, it switches for high power for a few milliseconds; the moment it's gone, it's back to low power. Or, one "eye" reserved for attack roles, one "eye" reserved for scanning. It'd actually be a valid reason to have two LIDAR modules set so close to each other.

The point about counterdetection is true of all active sensors—so of course, it'd make sense that the two "eyes" aren't the only sensors, just the most obvious.

You're only painting the target with high power for a small fraction of the time. You'd need ridiculously high power to destroy anything that way. And if your laser can achieve such power, why not use it to its full capability (i.e. continuously) ?

Well, I presume the bot isn't trying to set literally everything in its field of view on fire, which is why it'd toggle between high-power and low-power. Also, high-power scans may not be appropriate for all circumstances.

And yes, it's intended to be very high-powered. Most current weaponized laser applications are intended to destroy the target quickly, since they're often aimed at things like incoming missiles; if it takes a two-second burn to destroy a target moving at 200m/s (meaning that you can't count on striking the same spot for the entire engagement period), you don't have a usable weapon.

My unit conversion skills are rusty, but say you want to deliver 1000J of energy to your target within .1 sec. This is high-powered for a pistol bullet, low-powered for a rifle bullet. J = W/s gives us 10,000W, or 10kW. It's a lot in terms of household energy consumption, but then again, we are talking about a death ray.

At this point I'm glad I decided to cop out and make it a magic Death Ray. No need to actually work out the energy consumption relative to power output, seeing as how I can just declare that the android's mana core provides UNLIMITED POWAH!!

Lower end androids and military killbots are just powered by miniature fusion reactors, since the jump to Magitek in the story is a recent thing (seeing as I only just came up with it :p),

What if I wanted a Death ray to instantaneously nuke a small area? (Talking exclusively about the lower end androids now.) As in, the eyes flash briefly, and then something a mile away explodes like a suitcase nuke went off? Is that kind of thing possible with lasers, or do I need to pull a Graviton Particle Beam out of my ass?

What I mean is that the laser would have to be much more powerful than you actually need. If you want to burn your target with 10 kW but spend 99% of the time scanning, you'll need a 1 MW laser. If you never need to attack at 1 MW, then that's a waste.

Lasers are awfully inefficient, and create a lot of waste heat. There's always more power heating the laser than there is going through the beam. So if the beam is sending enough energy to have the effect of a nuke, well... and that's not getting into how you could power that.

edited 5th Mar '16 3:53:32 PM by Aetol

Understandable; pay no attention to laserchat then.

Well, no. It sounds like you're missing the part about throttling the power. 10kW is only for a brief attack pulse; the rest of the time it'd be operating in the milliwatt range. Given a fast enough transition, it'd be possible for the laser to switch to full power in the milliseconds that it's scanning over the target, and switch back down to milliwatt when scanning everything else.

It's a lot like a phased-array fire-control radar; it's capable of megawatt outputs when tracking a target far away and protected by jamming, but the rest of the time it's operating at much lower power. Since it can execute "track while scan"—that is, simultaneously lock on its targets in high-powered missile guidance mode, while also scanning the rest of the sky in low-powered search mode—it can put its full output energy to good use while not operating at full power all the time (and burning out nearby TV sets).

COMBUSTION MAN!

But if 10 kW is the maximal power, then you're really attacking at 100W (assuming again you're only attacking for 1% of the duration of the attack-scan cycles). And again, your laser is oversized for what you're actually doing with it.

Well, laserchat is still informative. It lets me know how much more advanced my fictional weapons need to be compared to real-life equivalents. I'm not exactly writing hard sci-fi, but I like to keep things internally consistent at least.

So, lasers are out for the purposes of instant nuke eye-beams, but is there any kind of contemporary technology that could produce a similar effect if it were given stupid amounts of power? Just so I have something I can base the tech on. Magitek Cryo-Death-Rays can be pulled wholly out of a writers ass, but the less advanced tech probably needs at least a cursory scientific foundation. What about X-Rays? I know nothing about their utility as weapons, but I'm pretty sure I've seen X-ray guns in fictitious settings before. If not those, then how about a particle beam? Fired from a miniaturised particle accelerator?

Looking at the J = W/s equation, I thought that was going to be a given? That your laser is going to have to be much more powerful than you'd think given the amount of energy you're going to deliver, since you'll be very limited in the amount of time to deliver it. If your target is dashing from cover to cover, or is a projectile rocketing toward your face, you'll have a fraction of a second to deliver your payload; that in turn implies a laser capable of drawing more power.

Although, you'd be right that the laser isn't powerful enough to do a true attack-while-scan option, given that the scanning speed would have to be measured in the 10Hz order of magnitude, and if we define "attack" as delivering at least 1000J of energy to a given target. That'd be an argument for having two lasers, symmetrical or asymmetrical, one for scanning, one for engagement.

Or, if the target can be targeted for a full two seconds at 10kW, or alternatively can be targeted for one second using both lasers (if you're willing to give up use of that sensor system for that second), the laser(s) can deliver a 20kJ pulse. If we ignore atmospheric blooming and other such inefficiencies, that's about as much as a .50 caliber Browning bullet, roughly enough to punch a nice hole through 20mm of steel.

So, in short, two LIDAR modules, each at 10kW, would give you a lot of options. For a snap-shot at 0.1sec, each individual laser can deliver a reasonable 1000J of energy, comparable to a low-end rifle bullet; it may seem little for a 10kW bullet, but that's what you get when you're limited to a tenth-of-a-second burn, and anyway that's more than enough to swat an incoming rocket or grenade. For a sustained shot at 1sec, each individual laser is capable of delivering a very respectable 10000J; we're somewhat out of antipersonnel weapon range now, and into the arena of light antimateriel weapons. You don't lose LIDAR capability if one scans while one attacks, and if you use both to scan, you can half the time between sensor sweeps.

That still leaves us with engineering problems, but they have built-in fusion reactors, I think they can handle the issue.

edited 6th Mar '16 1:48:48 PM by SabresEdge

Hmmm... and if said laser was ramped up to something stupid like, say, 999 Yottawatts? I can just have my supergenius invent some bullshit heatproof metal if melting is an issue.

That's probably well past the "vaporize everything in a wide area, including the launch platform" range.

Don't focus on numbers to start with; you can backfill those in. Start with capabilities. Effective range, what kinds of targets are destroyable, effective/sustained firing rate, side effects, all of those.