# Quiet Laser Guns **URL:** \ **Category:** Factual Questions\ **Created:** [June 12, 2003, 12:58am UTC](https://boards.straightdope.com/t/quiet-laser-guns/181248 "2003-06-12T00:58:10Z")\ **Posts on this page:** 18\ **Page:** 2
**Author:** ![Doc\_Nickel](https://avatars.discourse-cdn.com/v4/letter/d/5fc32e/32.png) [@Doc\_Nickel](https://boards.straightdope.com/u/Doc_Nickel)\ **Post date:** [June 12, 2003, 11:31pm UTC](https://boards.straightdope.com/t/quiet-laser-guns/181248/21 "2003-06-12T23:31:52Z")
Since said gland was biological, just be glad said sound wasn’t flatulent. Just think, Parker might have had to stock up on bean burritos to get the necessary pressure to … er, excrete out to such distances. 😃 Spidey’s _mechancial_ webshooters have gone “thwip” since 1964. We now return you to your regularly scheduled thread hijack. ---
**Author:** ![Snite](https://avatars.discourse-cdn.com/v4/letter/s/e0b2c6/32.png) [@Snite](https://boards.straightdope.com/u/Snite)\ **Post date:** [June 12, 2003, 11:59pm UTC](https://boards.straightdope.com/t/quiet-laser-guns/181248/22 "2003-06-12T23:59:41Z")
Hmmm, yes, you have all been very helpful, and this has been quite thought provoking on what I’m gonna do in my story now. At the moment, undecided, but you guys have been very helpful. Thank you. And I guess I could thank you for welcoming me as well. So I will: Thanks. Psychopachik Vampire ---
**Author:** ![The\_Ryan](https://avatars.discourse-cdn.com/v4/letter/t/7feea3/32.png) [@The\_Ryan](https://boards.straightdope.com/u/The_Ryan)\ **Post date:** [June 13, 2003, 4:43am UTC](https://boards.straightdope.com/t/quiet-laser-guns/181248/23 "2003-06-13T04:43:06Z")
> [@](#): > > \*Originally posted by Q.E.D. \* > \*\*What’s always bugged me is when the hero cop enters a buidling where the bad guy ran into, draws his gun, then _several minutes_ later, when he hears a faint sound or his Spidey sense tingles, he _finally_ cocks the weapon. Gah! > > Any real cop who did that would be called “target”. \*\* What’s really awful is when the good guy points a gun at the bad guy and says “stop” and the bad guy says “you won’t shoot me” and the good guy cocks the gun. I guess the idea is to show the bad guy that you’re really serious about shooting him, but wtf are you doing pointing an uncocked guy at someone in the first place? As for lasers being visible, there was a cartoon show called “Gargoyles” in which they explained this: the laserbeams themselves were far above the visible spectrum, but visible light was added as a tracer beam. I think it was meant as a subtle dig at all the shows which feature laser fights with beams crisscrossing the screen. ---
**Author:** ![Padeye](https://avatars.discourse-cdn.com/v4/letter/p/a9a28c/32.png) [@Padeye](https://boards.straightdope.com/u/Padeye)\ **Post date:** [June 13, 2003, 6:30am UTC](https://boards.straightdope.com/t/quiet-laser-guns/181248/24 "2003-06-13T06:30:55Z")
> [@](#): > > \*Originally posted by The Ryan \* > What’s really awful is when the good guy points a gun at the bad guy and says “stop” and the bad guy says “you won’t shoot me” and the good guy cocks the gun. I guess the idea is to show the bad guy that you’re really serious about shooting him, but \*\*wtf are you doing pointing an uncocked guy at someone in the first place? \*\* Emphasis mine. I also assume you mean uncocked **gun** or I completely misunderstood you. Sorry to pick a nit in this hijack but hammer down is correct for double action and double action only pistols and revolvers. ---
**Author:** ![SPOOFE](https://avatars.discourse-cdn.com/v4/letter/s/c5a1d2/32.png) [@SPOOFE](https://boards.straightdope.com/u/SPOOFE)\ **Post date:** [June 13, 2003, 7:13am UTC](https://boards.straightdope.com/t/quiet-laser-guns/181248/25 "2003-06-13T07:13:16Z")
> [@](#): > > The reason, of course, is that you can’t see a laser, so its kind of dull to show a big action scene. You can’t see a bullet, either, but gunfight scenes have been plenty exciting despite their visible absence. ---
**Author:** ![Darth\_Nader](https://avatars.discourse-cdn.com/v4/letter/d/ad7895/32.png) [@Darth\_Nader](https://boards.straightdope.com/u/Darth_Nader)\ **Post date:** [June 13, 2003, 7:20am UTC](https://boards.straightdope.com/t/quiet-laser-guns/181248/26 "2003-06-13T07:20:37Z")
> [@](#): > > \*Originally posted by The Ryan \* > \*\* wtf are you doing pointing an uncocked guy at someone in the first place? \*\* Man, if there was a hall of fame for typos… My hat’s off to ya, **The Ryan** , that’s just beautiful. ---
**Author:** ![GuanoLad](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/guanolad/32/42_2.png) [@GuanoLad](https://boards.straightdope.com/u/GuanoLad)\ **Post date:** [June 13, 2003, 12:21pm UTC](https://boards.straightdope.com/t/quiet-laser-guns/181248/27 "2003-06-13T12:21:44Z")
[Slightly off-topic] I figure that if we ever do get laser guns, they’d artificially include a noise just so you know that the gun was fired. And probably they’d make it a funky zappy noise just for geekiness’s sake. ---
**Author:** ![chairface56](https://avatars.discourse-cdn.com/v4/letter/c/977dab/32.png) [@chairface56](https://boards.straightdope.com/u/chairface56)\ **Post date:** [June 13, 2003, 12:47pm UTC](https://boards.straightdope.com/t/quiet-laser-guns/181248/28 "2003-06-13T12:47:02Z")
> [@](#): > > You can’t see a bullet, either, but gunfight scenes have been plenty exciting despite their visible absence. But, you can see a muzzle flash and hear a gunshot and thus we know a gun was fired. Imagine a movie gunfight scene where the guns didn’t make noise and had no muzzle flash. That is the kind of scene that was earlier described as being boring. Personally I think it’d be sorta surreal. ---
**Author:** ![smiling\_bandit](https://avatars.discourse-cdn.com/v4/letter/s/e9a140/32.png) [@smiling\_bandit](https://boards.straightdope.com/u/smiling_bandit)\ **Post date:** [June 13, 2003, 12:53pm UTC](https://boards.straightdope.com/t/quiet-laser-guns/181248/29 "2003-06-13T12:53:05Z")
> [@](#): > > [nitpick] Of course you can see them. First of all, the term laser refers to the device generating the beam, so they are always visible. Yes, I know you meant the laser beam, but that isn’t what you said. When this beam is emitted in the atmosphere, inevitably some of the light is scattered by dust and other airborne particulates and is therefore visible. I know you didn’t mean that either. What you meant to say is that in the near-vacuum of space, a laser beam is invisible. [/nitpick] Now THAT was a nitpick. Even in atmosphere, you can’t really see a laser beam much. And it was pretty obvious what I meant - besides, lingually the word laser refers to either the beam or the device. > [@](#): > > Personally I think it’d be sorta surreal. And really wierd - and not the kind of wierd that people like. All these fighters standing around acting out the image of shooting each toehr with weaponry, which has no noticable effect until one of them dies. Freaky. And not very good cinematography. ---
**Author:** ![RussellM](https://avatars.discourse-cdn.com/v4/letter/r/ed8c4c/32.png) [@RussellM](https://boards.straightdope.com/u/RussellM)\ **Post date:** [June 13, 2003, 12:58pm UTC](https://boards.straightdope.com/t/quiet-laser-guns/181248/30 "2003-06-13T12:58:04Z")
**Pleonast** Here are some useful sites showing the use of Nd:YAG lasers in ionisation and welding research [nce ionisation spectroscopy](http://nuclear.ph.man.ac.uk/~ktf/laspulse.html) [REMPI-LIF studies of simple ion-moleclue reactions](http://www.clf.rl.ac.uk/Reports/2001-2002/pdf/60.pdf) [Joining technology](http://www.tm.tudelft.nl/mideg/annual/reports/ouden.pdf) Here is the spec for a YAG laser [Laserex YAG-Laser LQ2106](http://www.medtecgmbh.de/Ellex-e/ellex-e.htm) which quotes it’s ionisation in air as approx 4mJ for a 4nS pulse YAG lasers are commonly used for welding metals (Ionisation of iron is 759 KJ/mol - why is it so bizarre to think that nitrogen can be ionised? Russell ---
**Author:** ![Hampshire](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hampshire/32/4887_2.png) [@Hampshire](https://boards.straightdope.com/u/Hampshire)\ **Post date:** [June 13, 2003, 2:21pm UTC](https://boards.straightdope.com/t/quiet-laser-guns/181248/31 "2003-06-13T14:21:06Z")
> [@](#): > > \*Originally posted by GuanoLad \* > \*\*[Slightly off-topic] > > I figure that if we ever do get laser guns, they’d artificially include a noise just so you know that the gun was fired. And probably they’d make it a funky zappy noise just for geekiness’s sake. \*\* Maybe they would beep like the lasers in the scanners at the checkout lines. “DIE! DIE!” (beep…beep…beep) ---
**Author:** ![GuanoLad](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/guanolad/32/42_2.png) [@GuanoLad](https://boards.straightdope.com/u/GuanoLad)\ **Post date:** [June 13, 2003, 10:33pm UTC](https://boards.straightdope.com/t/quiet-laser-guns/181248/32 "2003-06-13T22:33:53Z")
> [@](#): > > \*Originally posted by smiling bandit \* > \*\*All these fighters standing around acting out the image of shooting each toehr with weaponry, which has no noticable effect until one of them dies. Freaky. And not very good cinematography. \*\* Hmm. That proves that tracer fire would actually be necessary, otherwise how would you know you were aiming correctly. Actually, instead of resembling bullets, lasers could be swept across like an infinite blade. ---
**Author:** ![Padeye](https://avatars.discourse-cdn.com/v4/letter/p/a9a28c/32.png) [@Padeye](https://boards.straightdope.com/u/Padeye)\ **Post date:** [June 13, 2003, 11:07pm UTC](https://boards.straightdope.com/t/quiet-laser-guns/181248/33 "2003-06-13T23:07:09Z")
> [@](#): > > \*Originally posted by GuanoLad \* > \*\*Hmm. That proves that tracer fire would actually be necessary, otherwise how would you know you were aiming correctly. > > Actually, instead of resembling bullets, lasers could be swept across like an infinite blade. \*\* Optical sights with superimposed red dots are old school technolgy now. You look through the sight with both eyes open and shoot where you see the dot. Unlike a laser sight it doesn’t project so you won’t give your position away. ---
**Author:** ![Sinungaling](https://avatars.discourse-cdn.com/v4/letter/s/838e76/32.png) [@Sinungaling](https://boards.straightdope.com/u/Sinungaling)\ **Post date:** [June 14, 2003, 8:57pm UTC](https://boards.straightdope.com/t/quiet-laser-guns/181248/34 "2003-06-14T20:57:45Z")
Hey, I remember Gargoyles too. The explanation actually was that the fancy weapons were microwave guns, but the laser was added for targetting. I was impressed that the writers even bothered to add the scientific spin. I also liked the explanation for how man-sized creatures could have the energy to glide, as well as fight and talk and other stuff. ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [June 14, 2003, 11:33pm UTC](https://boards.straightdope.com/t/quiet-laser-guns/181248/35 "2003-06-14T23:33:15Z")
> [@](#): > > \*Originally posted by smiling bandit \* > \*\*Also, please note that sci-fi stories usually don’t use lasers. Star wars may call them “turbolasers” but they obviously are not. Star trek has Phasers, and so forth. And not one of them has anything that has the properties of a laser. DUne did have them, but the Frank Herbert was slightly-above an idiot and used them in the dumbest possible way. > > The reason, of course, is that you can’t see a laser, so its kind of dull to show a big action scene. \*\* The star trek “phaser” means “phase modulated laser” which is a typical star trek type of name. Emphasis is placed on how cool the name sounds rather than what it really means and whether or not the name actually makes sense (like sonic shower). But a phaser really is a laser, or at least it was originally. Star trek also isn’t consistant with its own technology, so they may have fuddled the definition of “phaser” over the years. ---
**Author:** ![Pleonast](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pleonast/32/1183_2.png) [@Pleonast](https://boards.straightdope.com/u/Pleonast)\ **Post date:** [July 11, 2003, 4:37pm UTC](https://boards.straightdope.com/t/quiet-laser-guns/181248/36 "2003-07-11T16:37:04Z")
**RussellM** : > [@](#): > > Here are some useful sites showing the use of Nd:YAG lasers in ionisation and welding research > nce … > > Here is the spec for a YAG laser Laserex YAG-Laser LQ2106 which quotes it’s ionisation in air as approx 4mJ for a 4nS pulse > > YAG lasers are commonly used for welding metals (Ionisation of iron is 759 KJ/mol - why is it so bizarre to think that nitrogen can be ionised? (And sorry for the long delay in my reply) Of course nitrogen can be ionized (its ionization energy is only twice that of iron’s). The problem is getting that energy into the molecule. Nitrogen is very nearly transparent to visible light; that’s the 0.02 dB/km attenuation. Since the vast majority of the laser’s energy passes straight through the air, you need a really powerful laser to dump enough energy into the air to ionize it. REMPI-LIF study you cited supports this (if I read it correctly). The are looking at NO spefically because for N[sub]2[/sub] “the ionization step is rather inefficient”. (Please see the [REMPI-LIF study](http://www.clf.rl.ac.uk/Reports/2001-2002/pdf/60.pdf) for the complete context.) I should point a possible flaw in my calculation: I assume all the processes are linear. At the very high energies I ended up with, I expect that non-linear effects may become important. I also assume that the laser is not tuned to any of the transitions of N[sub]2[/sub]. ---
**Author:** ![smiling\_bandit](https://avatars.discourse-cdn.com/v4/letter/s/e9a140/32.png) [@smiling\_bandit](https://boards.straightdope.com/u/smiling_bandit)\ **Post date:** [July 11, 2003, 4:57pm UTC](https://boards.straightdope.com/t/quiet-laser-guns/181248/37 "2003-07-11T16:57:08Z")
> [@](#): > > The star trek “phaser” means “phase modulated laser” which is a typical star trek type of name. Emphasis is placed on how cool the name sounds rather than what it really means and whether or not the name actually makes sense (like sonic shower). But a phaser really is a laser, or at least it was originally. Star trek also isn’t consistant with its own technology, so they may have fuddled the definition of “phaser” over the years. I don’t believe there was ever an official explanation of what “phaser” meant: in other words, I am pretty sure you definition is a fanboy thing, since I have heard several variations, with no source. Regardless, the only logical thing including the words “phase” and “laser” is Phase Coherent, and lasers already are. Which is still pointless, since Star Trek weapons display no property of a laser. Star trek weapons seem to simply stop when they hit refined metal (sometimes failing to damage the beige upholstery when set on kill), can heat rocks with a “wide beam” and kill people, making them dissapear, without actually vaporizing them. There is no scientific explanation for these phenomena. Its not possible with what we know of science. Perhaps that will change someday, but I can positively assert to you that the phaser is not a laser device. ---
**Author:** ![msmith537](https://avatars.discourse-cdn.com/v4/letter/m/d9b06d/32.png) [@msmith537](https://boards.straightdope.com/u/msmith537)\ **Post date:** [July 11, 2003, 6:08pm UTC](https://boards.straightdope.com/t/quiet-laser-guns/181248/38 "2003-07-11T18:08:47Z")
> [@](#): > > \*Originally posted by engineer\_comp\_geek \* > Emphasis is placed on how cool the name sounds rather than what it really means and whether or not the name actually makes sense (like sonic shower). But a phaser really is a laser, or at least it was originally. Star trek also isn’t consistant with its own technology, so they may have fuddled the definition of “phaser” over the years. \*\* Emphasis is also placed on “coolness” of the technology, not practiality. Sonic shower? Something wrong with “water”? Of course, my favorite sci-fi weapon has to be the “pulse” rifles and “smart” guns of Aliens. “Pulses” of what? 10mm HE, your standard armor piercing round? Random high pitched noises and muzzle flashes? Yeah and those “smart” guns seem like real precision weapons. Plus all the accessories - grenade launcher, flame thrower (always appropriate for claustrophobic spaces like spaceships and mining colonies), motion tracker, silencer, LOUDENER, flash ENHANCER, voice activation (LETS ROCK!!!). [Previous page](https://boards.straightdope.com/t/quiet-laser-guns/181248.md?page=1)