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  #1  
Old 07-24-2010, 03:41 PM
Babale Babale is offline
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Fun Stuff to do With a Laser Pointer

I just got my first ever laser-pointer (I know, I know...) and have used it mostly too... point at things. But then I decided to make my young cousin a laser scope for his toy gun and that was way more fun then pointing at stuff.

So what other stuff can I do with my laser pointer?

Oh, and any idea on how I can use it to convince someone that they are being haunted?
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  #2  
Old 07-24-2010, 03:50 PM
Lobsang Lobsang is offline
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What colour is it?

One cool thing to do is to combine it with long exposure photography.

eta: and/or cats.

Last edited by Lobsang; 07-24-2010 at 03:53 PM..
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  #3  
Old 07-24-2010, 03:53 PM
Babale Babale is offline
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Originally Posted by Lobsang View Post
What colour is it?

One cool thing to do is to combine it with long exposure photography.
Red.

And yeah, I was thinking about the photography thing earlier since when I move it really fast it leaves trails on the floor.

EDIT: ha, on the way home I ran into a stray cat and shined it at him but he ignored me. I need to find a house cat

Last edited by Babale; 07-24-2010 at 03:54 PM..
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  #4  
Old 07-24-2010, 07:22 PM
Raguleader Raguleader is offline
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One of the EOD guys in our squadron has a green laser light pen, and mostly he used it to demonstrate how it could make an intense bright green dot on the wall in the secretary's office at the other end of our building (maybe a couple hundred feet long, with one long hallway)

From what I understand, combat controllers in the Air Force use laser pointers to guide laser-guided bombs down to their targets. They can even move the pointer around and the bomb will re-aim itself in mid-fall. You can get those bombs to do some neat tricks if you move the laser at the last second.

I don't know if you have any laser-guided bombs handy, but if you do, I'd check with your landlord or your HOA before you started playing with it and a laser pointer.
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  #5  
Old 07-24-2010, 08:10 PM
Mangetout Mangetout is offline
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Cats, yeah.

Actually - other animals too - I went to the sea life centre once and the otters were a bit sullen and withdrawn, staying right at the far end of the indoor part of their enclosure - I managed to coax them out and across a couple of plank walkways, right onto a little island right in front of the fence.

Earlier on in the same visit, I managed to convince my (then quite young) kids I could command fish - there was an aquarium tank with a large group of small fish - by concealing the pointer in my left hand, pretending to lean on the wall above the glass, I was able to project a moving spot on the gravel substrate, whilst gesturing accordingly with my right hand - the spot of light was almost invisible to bystanders, but the fish noticed it and gave chase - appearing to be under control of my hand gestures.

I'm sure both of these activities would have seen me unceremoniously ejected from the venue if the staff had become aware of them - although in truth, I think I did the otters a favour - they were so bored, I think they welcomed the diversion.
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  #6  
Old 07-24-2010, 08:36 PM
N9IWP N9IWP is offline
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Green lasers are great for pointing out constellations, but since you have a red one that blows that idea.

I don't think diode based lasers are good for holography, but you could try

Brian
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  #7  
Old 07-24-2010, 08:46 PM
capybara capybara is offline
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Cats.
You can really piss off lecturing art historians.
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  #8  
Old 07-24-2010, 10:13 PM
Ale Ale is offline
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Cats, definitely cats!. It's like having remote controlled little furry missiles.

A few months ago I was at a home-stay in Mabul island where they have three young cats roaming free. Every time I opened the room door they tried to sneak in and rummage through my luggage, looking for snacks I suppose. I carry a small red laser pointer and torch in my camera bag so I can either use it to look for things inside the bag when it's dark, or use the laser to point at something interesting when my GF is taking pictures.
So, after a day of chasing three very active cats out of the room I got wise, took out the laser pointer and every time I opened the door, when the cats started coming I'd shine it on the floor in front of the door, wiggling it a little. When the felines where mesmerized enough I'd quickly move it across the floor to the far end of the hall and out the back door. The cats darted behind it leaving me the chance to get out (or in) the room unmolested.

Now I wonder, if I could do something similar if I ever stumble across a tiger while trekking...
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  #9  
Old 07-25-2010, 01:02 AM
ducati ducati is offline
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Once upon a time, when laser pointers were a new, novel idea, I got one.
I went to BIL2's bachelor party with BIL1. B1 and I were at one end of a 40 foot table, and a friend of B1 and B2 was at the other end.
I was messing around by placing the dot on people's ketchup bottle or salt shaker from across the restaurant then turning it off before they could find me.

The friend at the other end of the table motioned that he wanted to see this thing; they weren't very common after all. I took it down to him, and came back to my seat, only to see him shining in his eye! He would point it away, then hold it back up to his eye, just smiling and having a ball. I waved frantically for him to stop - the music and noise prevented any chance of yelling. He just smiled and waved back, still shining the damn thing right into his eyeball. As I jumped up to rush down and try to save what's left of his vision, BIL1 grabbed me and stopped me. "He's got a glass eye, doofus. He's just messing with you!" I wanted to punch him then, but it was pretty funny.



Last year, we took the kiddies to Myrtle Beach for spring break. We try different places every year, and I heard they had good golf, so we went. I was unaware that it was the redneck Riviera of the East coast. We were the only family in town that week with 4 matching tires and all of our teeth. But I digest...

Jr. took my green laser pointer to the balcony of our 22nd floor room one night, and shone it on the beach. It's very powerful, and shone a bright green dot on the sand.
Immediately, it was joined by 1, then 2, then 4, then more red dots, all pointing at the same trash can. He moved it away to a chair, and the dots followed. Everytime he would change targets, the red dots would chase the green. Then, he would just race it up and down the beach, tracing shapes and stopping on things, and the red dots would just chase the green no matter what. We looked over the railing straight down, and could see kids (and grown-ups) hanging over their railings at different floors. We all just laughed and waved at each other, then went back to annoying people on the beach.

Good times.


Downside of a green laser, especially a strong one - it points to you as well, especially at the beach with the moisture in the air at night. I walked over a mile south of the hotel, then radioed back to Jr. to hit me with it. Zap! Like a green string, it showed me exactly what room he was in! There's no hiding or lying when you do that; it stands out like a bright green sore thumb! If you're off-axis by about 15 to 20 degrees or so, you can't see it, but inside that 30 degree slice, anyone can see exactly where you are. No wonder the Feds catch people who do this to airplanes.
"Hey Bob- you see the laser beam there?" "Yeah, looks like a white pickup at the Wal-Mart. Call company security & let them know."
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  #10  
Old 07-25-2010, 01:36 AM
Superhal Superhal is offline
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I would get every mirror in the house and try to point at stuff while bouncing off the mirrors, like that old mcdonalds commercial where MJ and Bird play Horse.

I'd also try to see how many bounces I could get off 2 mirrors.

But, the laser sight for a toy gun is the best. I would make a laser-guided rubberband gun.
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  #11  
Old 07-25-2010, 02:07 AM
Babale Babale is offline
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Yep, it was really fun to add laser sights to my cousin's toy guns. Of course, since the guns don't actually fire anything, I probably would have had fun with him anyways (I took him to a grove and we went hunting for zombies. Kids have great imaginations.)

Felt like Call of Duty.
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  #12  
Old 07-25-2010, 03:26 AM
cardinal_fang cardinal_fang is offline
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Dogs too.
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  #13  
Old 07-25-2010, 03:26 AM
needscoffee needscoffee is offline
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My daughter tapes it to her BB gun.
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  #14  
Old 07-25-2010, 07:23 AM
longPath longPath is offline
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Get an empty can. The bigger the better but at least the size of a #10 tomato can.
Remove the bottom and stretch the remains of a balloon over one end.
Fasten a piece of mirror or other reflective material to the membrane.
Aim laser at reflector from some distance and be amused at the patterns the reflected beam makes when you shout into the can.

I once read that it was possible to eavesdrop on conversations at a distance by demodulating a laser beam bounced off a subjects windows. This was an experiment to see if it was possible using resouces at-hand. We never got to the demodulation phase.

It kept us entertained for several minutes.

The other thing that was fun was to shine the beam at distant road signs. They would light up like magic!

Last edited by longPath; 07-25-2010 at 07:27 AM..
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  #15  
Old 07-25-2010, 08:04 AM
danielpower danielpower is offline
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My puppy loves chasing the green laser beam.
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  #16  
Old 07-25-2010, 09:02 AM
billfish678 billfish678 is offline
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Take a clear large plastic bottle. Say 2 liter. Put a nice hole in the side near the bottom (but where the plastic is flat. Have a water source feeding into it from the top. What you want to create is a nice arcing stream of water that is a solid "tube" so to speak. Aim laser beam through plastic bottle into the hole/stream on the other side.

If you do it right, the light will be trapped in that stream of water (due to total internal reflection) and you won't really see it in there (assuming clear water without significant bubbles). The light however, will escape where the tube breaks up or the surface it splashes on. Its like splashing light. When done properly in a dimly lit room it can be pretty neat.
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  #17  
Old 07-25-2010, 07:14 PM
limegreen limegreen is offline
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Suspend a small mirror so that it rests against an old speaker cone. Turn off the lights, turn up the music, and aim the laser at the mirror. Your own light show! My high school physics classes love this one.
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  #18  
Old 07-25-2010, 07:31 PM
Sunspace Sunspace is online now
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Originally Posted by Ale View Post
Now I wonder, if I could do something similar if I ever stumble across a tiger while trekking...
You're going to need a bigger laser.
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  #19  
Old 07-26-2010, 07:39 AM
RalfCoder RalfCoder is offline
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A backyard astronomer friend of mine used to use his to turn off the street light that lit up his yard. He would hit the photo sensor on it with the laser for a few seconds, enough to convince the light that it was still day time. Probably took a pretty steady hand, though, or some sort of aiming mount.

I've done the "stupid animal tricks" bit with mine. 2 of the cats love it. They come running when they hear that click. #3 ignores it most days.

Road signs, license plates, and tail lights light up like magic when you can hit them. Use caution so you don't blind oncoming traffic, of course. I once had an oncoming carload of teenagers hit me with one while driving. It was only for an instant, but still unnerving.
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  #20  
Old 07-26-2010, 07:57 AM
CalMeacham CalMeacham is offline
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Cats and even dogs like chasing the spot. (Not our Midnight, though. She'd look at the spot, look up at your hand with the laser pointer, and effectively say you're doing that, and ignore it.)


Two guys actually got a patent on the idea of using a laser pointer as a cat toy. Not for a cat toy using a pointer, but for the very concept. It shouldn't have been granted in the first place, and almost certainly wouldn't have withstood a legal challenge, but they did get it -- I've been through the legal documents. Unfortunately, they didn't keep up the payments (Federal law requires a series of payments through the life of the patent -- a wrinkle added in 1970 that I hadn't known about until I researched this), so their patent lapsed.



I'd caution anyone against any playing that would lead to the possibility of the laser being shined into people's eyes. And there are infinite possibilities for this when you consider how many reflecting surfaces there are. So i don't think laser sighting scopes on toy guns is a good idea. I'm also annoyed by jerks who put the lights on athletes in competition, performers, or speakers. And shining a pointer into the faces of drivers and pilots is just stupid and, in some cases, against the law.


DON'T Do IT
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  #21  
Old 07-26-2010, 08:14 AM
billfish678 billfish678 is offline
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Originally Posted by RalfCoder View Post
A backyard astronomer friend of mine used to use his to turn off the street light that lit up his yard.
For people who know some astronomy, trying to show other people the night sky, laser pointers have been nearly a god send.

I remember the years of "see that star....no, not that one, the other one...which one?..." ARGGHHH!

Now, with a laser pointer, get somebody to stand next to you, aim that sucker in whatevers direction, and they can SEE which thing you are pointing to.
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  #22  
Old 07-26-2010, 08:54 AM
Ale Ale is offline
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Sunspace, I'd like to use it to distract the tiger, not to slice it in half and set the forest on fire.


Quote:
Originally Posted by RalfCoder View Post
Road signs, license plates, and tail lights light up like magic when you can hit them. Use caution so you don't blind oncoming traffic, of course. I once had an oncoming carload of teenagers hit me with one while driving. It was only for an instant, but still unnerving.
Heh, now I picture your car having one of these on the roof.

[Paul Hogan]That's not a laser... this is a laser.[/Paul Hogan]

Car full of punks goes up in a poof of smoke.
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  #23  
Old 07-26-2010, 09:02 AM
CalMeacham CalMeacham is offline
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Heh, now I picture your car having one of these on the roof.

[Paul Hogan]That's not a laser... this is a laser.[/Paul Hogan]

Car full of punks goes up in a poof of smoke.
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Yeah.


No joke -- I can see "laser dueling" or "laser jousting" -- shining lasers at opposite cars by laser -equipped jerks -- as a real possibility. You don't need Lucas-sued high-power laser pointers to make this a potentially dangerous situation.
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  #24  
Old 07-26-2010, 10:27 AM
dmatsch dmatsch is offline
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Originally Posted by N9IWP View Post
Green lasers are great for pointing out constellations, but since you have a red one that blows that idea.

I don't think diode based lasers are good for holography, but you could try

Brian

If you happen to have a green laser AND a red one, for Og's sake don't cross the streams. It would be bad. Giant Twinkie kind of bad that I wouldn't have to tell you about.
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Old 07-26-2010, 10:33 AM
MeanOldLady MeanOldLady is offline
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Originally Posted by needscoffee View Post
My daughter tapes it to her BB gun.
I laughed. Your daughter is hilarious.
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  #26  
Old 07-26-2010, 10:54 AM
Sunspace Sunspace is online now
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Originally Posted by dmatsch View Post
If you happen to have a green laser AND a red one, for Og's sake don't cross the streams. It would be bad. Giant Twinkie kind of bad that I wouldn't have to tell you about.
But add a blue one and everything's all full-colour okay!
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  #27  
Old 07-26-2010, 11:43 AM
CalMeacham CalMeacham is offline
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If you happen to have a green laser AND a red one, for Og's sake don't cross the streams. It would be bad. Giant Twinkie kind of bad that I wouldn't have to tell you about.
I actually once built a measuring device that did precisely this. It worked beautifully. Sometimes crossing the streams is the best thing to do.




As far as holography goes,

1.) There's no reason you can't use a diode laser, but I wouldn't use a handheld pointer -- it'd shake too much.

2.) Laser pointers aren't well known for their coherence length, and it's the coherence length that limits the size of your hologram. Dennis Gabor's holograms (made over a decade before the laser was invented) had a thickness that could be measured in microns, because filtered mercury light has a short coherence length.

3.) you can get small lasers with much longer coherence lengths than laser pointers for about the same cost, I think. So pointers probably aren't your best choice.
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  #28  
Old 07-26-2010, 12:10 PM
billfish678 billfish678 is offline
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Originally Posted by CalMeacham View Post
[
2.) Laser pointers aren't well known for their coherence length, and it's the coherence length that limits the size of your hologram.
Its not as bad as you think.

http://www.holoworld.com/holo/diode.html
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  #29  
Old 07-26-2010, 12:23 PM
CalMeacham CalMeacham is offline
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Hmm.

I don't trust his statement that "the laser pointer doesn't have to be tied down". Unless your exposure is a quick flash, any unsteadiness in your hand is going to "smear" out the interference fringes that are the very basis of holograms. Every setup I've used -- and every one I've read about -- has had source, plate, and object firmly secured.
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  #30  
Old 07-26-2010, 12:31 PM
billfish678 billfish678 is offline
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Originally Posted by CalMeacham View Post
Hmm.

I don't trust his statement that "the laser pointer doesn't have to be tied down". Unless your exposure is a quick flash, any unsteadiness in your hand is going to "smear" out the interference fringes that are the very basis of holograms. Every setup I've used -- and every one I've read about -- has had source, plate, and object firmly secured.
I've done what he's done. And worse. Not handheld mind you. But you can make some nice holograms with cheap laser pointers and without 2 ton granite tables, temp controlled labs, and everthing bolted the bejezuss down.

The guy has DONE this stuff and others have replicated it.

Last edited by billfish678; 07-26-2010 at 12:34 PM..
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  #31  
Old 07-26-2010, 12:39 PM
billfish678 billfish678 is offline
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Missed edit window.

I think you either misread (or he miswrote) that he was suggesting that you could make a hologram handholding the laser during the exposure.

The more important point being a cheap laser pointer can have more than enough coherence length to make a good hologram.
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  #32  
Old 07-26-2010, 12:45 PM
CalMeacham CalMeacham is offline
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I think you either misread
No, I didn't misread it -- he said it.

And I didn't say you had to have granite tables. Heck, Unterseher has you making holograms in a sandbox. But I don't buy that you can hand-hold the laser pointer and get good results.

I'll also accept that some laser pointers will have enough coherence length, but I doubt if they all do, and choosing one at random isn't the best way to find one that'll work.
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  #33  
Old 07-26-2010, 01:01 PM
billfish678 billfish678 is offline
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Originally Posted by CalMeacham View Post
Quote:
I think you either misread
No, I didn't misread it -- he said it.

And I didn't say you had to have granite tables. Heck, Unterseher has you making holograms in a sandbox. But I don't buy that you can hand-hold the laser pointer and get good results.

I'll also accept that some laser pointers will have enough coherence length, but I doubt if they all do, and choosing one at random isn't the best way to find one that'll work.
Depends on the chance of having a good one vs a bad one doesnt it?. You can buy a bunch of cheap laser pointers for the cost of one lab quality HeNe, much less a HeNe thats more than a few milliwatts. Then consider how fragile and power hungry one is vs how small, durable, and low power consumption the other is.

Hey, point out where he said the hand holding thing and I''ll see what I think he was saying.

PS, the first cheap pointer we tried worked nicely.
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  #34  
Old 07-26-2010, 01:57 PM
CalMeacham CalMeacham is offline
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Hey, point out where he said the hand holding thing and I''ll see what I think he was saying.


You don't have to interpret -- I can read him just fine:

Quote:
I could have mounted the laser pointer and spatial filter on a tripod and shot the reference beam down at the required angle. Remember, the ONLY part of your system that needs to have vibration isolation with single-beam holography is the object and the plate. The laser and lens/spatial filter does NOT have to be isolated or even located on the table.
http://www.holoworld.com/holo/diode7.html
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  #35  
Old 07-26-2010, 02:15 PM
billfish678 billfish678 is offline
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Originally Posted by CalMeacham View Post
Quote:
Hey, point out where he said the hand holding thing and I''ll see what I think he was saying.


You don't have to interpret -- I can read him just fine:

Quote:
I could have mounted the laser pointer and spatial filter on a tripod and shot the reference beam down at the required angle. Remember, the ONLY part of your system that needs to have vibration isolation with single-beam holography is the object and the plate. The laser and lens/spatial filter does NOT have to be isolated or even located on the table.
http://www.holoworld.com/holo/diode7.html
That DOESNT mean its handheld does it? You said "handholding". I sure don't see that in there anywhere. He said on a tripod for pete's sake.

The dude has a website that details making holograms. He started it over 10 years ago. He MAKES them. He teaches classes on making them. He has plenty of actual specs on most pages.

What do you think is most likely?

He's made up the whole thing?

He's just made up this one thing?

He's not quite right on one thing?

Your impression of what will work and not work aint quit right? ( You do realize that people have done holography with no vibration isolation right?)

You did notice it is single beam reflection holography he was talking about didnt you?

Call him or email him and see if he's actually done what he says is doable.

Oh, all my references are in storage, but now that I think about it, I seem to recall that the laser actually being on the vibration isolation table wasnt required being mentioned a time or two as well.

Last edited by billfish678; 07-26-2010 at 02:19 PM..
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  #36  
Old 07-26-2010, 02:23 PM
Floppy Joe Floppy Joe is offline
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Back in my halcyon days, we had prepared a dark and smokey room (don't ask). In the center of the room, hanging by a thread was on of those large, round, faceted crystals. Pointing the red pointer at the crystal, you could see the myriad beams of laser light being reflected all over the room.

Pretty trippy, I tell ya what.
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  #37  
Old 07-26-2010, 02:33 PM
CalMeacham CalMeacham is offline
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That DOESNT mean its handheld does it? You said "handholding". I sure don't see that in there anywhere. He said on a tripod for pete's sake.

The dude has a website that details making holograms. He started it over 10 years ago. He MAKES them. He teaches classes on making them. He has plenty of actual specs on most pages.

What do you think is most likely?

He's made up the whole thing?

He's just made up this one thing?

He's not quite right on one thing?

Your impression of what will work and not work aint quit right? ( You do realize that people have done holography with no vibration isolation right?)

You did notice it is single beam reflection holography he was talking about didnt you?

Call him or email him and see if he's actually done what he says is doable.
Jeez, calm down.


I've made holograms.I've made single-beam holograms. I;'m not accusing him of making things up. He doesn't say "handholding", but he does say that "the only part that needs vibration isolation is the object and the plate:", which seems not right to me, and implies that you could do it handheld, which I admit is hyperbole for "not tied down.


But you're taking this far too personally.
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  #38  
Old 07-26-2010, 03:02 PM
billfish678 billfish678 is offline
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Originally Posted by CalMeacham View Post
I've made holograms.I've made single-beam holograms. I;'m not accusing him of making things up. He doesn't say "handholding", but he does say that "the only part that needs vibration isolation is the object and the plate:", which seems not right to me, and implies that you could do it handheld, which I admit is hyperbole for "not tied down.

You are reading stuff into it that just ISNT there. He didn't say handheld. He didnt even apparently say not tied down. He just said NOT on the vibration isolation table.

You need to think about that bolded part a bit.

Yeah, I am going to get a bit peeved because you think a guy (who actually does the stuff) is wrong because you are virtually making stuff up about what he said and then imply he doesnt know what he is talking about because of stuff you made up.

Last edited by billfish678; 07-26-2010 at 03:02 PM..
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  #39  
Old 07-26-2010, 03:43 PM
Bookkeeper Bookkeeper is online now
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Two of our three cats go nuts over the laser pointer (the other just looks at you and goes "Meh"). I have one I got as a freebie at a conference (combination pen, USB key, and laser pointer) that is easily visible on the side of the apartment building 3 blocks away. I can see why these are dangerous to airplane pilots at night!
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  #40  
Old 07-26-2010, 08:53 PM
billfish678 billfish678 is offline
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I sent the Holoworld guru/creator Frank DeFreitas a quick email about not having the laser on the vibration isolation table. Here is part of his response:



Hello Bill. Thank you for your kind words.


Not only does the laser not have to be on the vibration isolation table for single beam holograms, it was a practice back in the days of DCG recording to actually TAP on the laser to reduce speckle in the final images.

Last edited by billfish678; 07-26-2010 at 08:56 PM..
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  #41  
Old 07-27-2010, 04:05 PM
Babale Babale is offline
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Originally Posted by Bookkeeper View Post
Two of our three cats go nuts over the laser pointer (the other just looks at you and goes "Meh"). I have one I got as a freebie at a conference (combination pen, USB key, and laser pointer) that is easily visible on the side of the apartment building 3 blocks away. I can see why these are dangerous to airplane pilots at night!
It's all those things?

One of those and an iPad and you never need anything else ever again.
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  #42  
Old 07-27-2010, 04:14 PM
Swallowed My Cellphone Swallowed My Cellphone is offline
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Originally Posted by Ale View Post
Now I wonder, if I could do something similar if I ever stumble across a tiger while trekking...
Tigers ignore laser pointers, you'd need a laser flashlight.
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  #43  
Old 07-27-2010, 04:18 PM
Sunspace Sunspace is online now
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Originally Posted by Babale View Post
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Originally Posted by Bookkeeper View Post
Two of our three cats go nuts over the laser pointer (the other just looks at you and goes "Meh"). I have one I got as a freebie at a conference (combination pen, USB key, and laser pointer) that is easily visible on the side of the apartment building 3 blocks away. I can see why these are dangerous to airplane pilots at night!
It's all those things?

One of those and an iPad and you never need anything else ever again.
You also need a knife. Unless that's built in as well.
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  #44  
Old 09-16-2010, 01:16 AM
Jacober Jacober is offline
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i always use green laser pointer to point the stars, and sometimes use it to teach.
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Old 09-16-2010, 07:47 AM
Sailboat Sailboat is offline
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Originally Posted by cardinal_fang View Post
Dogs too.
I'd like to point out that the current thinking I've been seeing on dog-themed message boards is that use of laser pointers -- or any moving light -- as a dog toy is counterindicated.

The risk is habituating the dog to chasing moving light. Other moving lights, including headlights from passing cars, streetlights shining through moving tree branches, and so on, can not only cause the dog to actively make noise in the middle of the night, but, since they go on all night, can induce a lot of tension and strain in dogs who are used to getting all keyed up for a moving light. Some dogs have become nervous wrecks after getting obsessed with lasers. Some people have reported their dogs now bark in frustration at every moving light.

IMHO it's not worth it.
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Old 09-16-2010, 09:22 AM
Max Torque Max Torque is offline
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I discovered that my green laser pointer makes some funky patterns if I shine it at my wife's crystal knickknacks. She has this little village made of Waterford crystal, and the crystal breaks the laser up into some crazy scatter-patterns, especially in a darkened room. The crystal candy jar makes even crazier patterns.
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  #47  
Old 09-16-2010, 11:05 AM
control-z control-z is online now
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Wet blanket here. I've been reading that the infrared scatter from cheap green laser pointers can damage your eyes: http://www.technewsdaily.com/dangero...pointers-1036/

Of course any laser pointer can damage eyes, kids playing with them tend to make me nervous.
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  #48  
Old 09-16-2010, 01:04 PM
cjepson cjepson is offline
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Originally Posted by Max Torque View Post
I discovered that my green laser pointer makes some funky patterns if I shine it at my wife's crystal knickknacks. She has this little village made of Waterford crystal, and the crystal breaks the laser up into some crazy scatter-patterns, especially in a darkened room. The crystal candy jar makes even crazier patterns.
All kinds of glass objects do this. Try empty jars (especially those with rough sections around the bottom). Or drinking glasses with some sort of texture to them.
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  #49  
Old 09-16-2010, 08:11 PM
Jacober Jacober is offline
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Originally Posted by control-z View Post

Of course any laser pointer can damage eyes, kids playing with them tend to make me nervous.
i agree, last month my neighbor bought a 100MW green laser pointer from Elecronic Gadgets and one day his eyes was hurt by green laser, so be careful anyone use it.
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  #50  
Old 09-28-2012, 12:34 PM
Jimeeb Jimeeb is offline
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Originally Posted by Raguleader View Post
One of the EOD guys in our squadron has a green laser light pen, and mostly he used it to demonstrate how it could make an intense bright green dot on the wall in the secretary's office at the other end of our building (maybe a couple hundred feet long, with one long hallway)

From what I understand, combat controllers in the Air Force use laser pointers to guide laser-guided bombs down to their targets. They can even move the pointer around and the bomb will re-aim itself in mid-fall. You can get those bombs to do some neat tricks if you move the laser at the last second.

I don't know if you have any laser-guided bombs handy, but if you do, I'd check with your landlord or your HOA before you started playing with it and a laser pointer.
I would imagine that if you have bombs laying around that Homeland Security would be interested in this also.
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