Talk:Laser pointer

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Radiation[edit]

What about those Radiation Exposure warnings? Question posted 5 July 2007 by 67.168.67.243

What about them? Light is radiation and lasers produce intense (and sometimes hazardous) light. Pzavon 02:27, 7 July 2007 (UTC)

Purple lasers[edit]

dont see what a $200,000 purple DPSSS laser has to do with laser POINTERS , article should relate only to items available as a laser POINTER ???—Preceding unsigned comment added by 86.0.207.24 (talk) 00:48, 11 August 2006 (UTC)

Purple laser pointers using 405 nm GaN laser diodes (no DPSS) canabalized from Blu-ray disc units or diverted from their manufacture, are now available for less than $50. Technology progresses. SBHarris 19:20, 9 June 2010 (UTC)
That, sir, must be a contender for longest time between a post and the followup. --Nucleusboy (talk) 21:07, 14 June 2010 (UTC)

Added USA federal act info[edit]

I have added details of recent federal USA law , article looking a lot tidier slashme , i would like to see the details back about the inventor of blue lasers , the articles a hoot ! about how he was a failed inventor and discovered blue laser light by accident . Also would like to see details back about the FUTURE of blue lasers as it will become the standard in future taking over from red due to mass production .......but i guess yuo must have had reason for removing those pieces i entered in previous article Visitor not registered - 10.12.05 - paul bluesky

Hi Paul. The reason I removed that copy was because it didn't really fit in the laser -pointer- article. Maybe you could put it in the laser diode article instead. I'll watch that page too, see what you come up with! :] --Slashme 08:18, 10 December 2005 (UTC)

Pet's mental heatlh[edit]

Hi, we have a question. What do you think about the mental health of the dog hunting the laser spur. Should we be worried be cause the dog acts like crazy.

Dunno whether you're serious, but I'll answer as if you are: If the dog's having fun chasing it, great. If it looks like that infuriating red spot is freaking the poor sucker out too much, give him a break. Remember, your dog doesn't have to make a living, so if he's a nutter, who cares?  :-) --Slashme 17:21, 15 January 2006 (UTC)
Yeah, i've seen that too in cats - some of them go mad for the laser and other are scared of it. I guess it just depends on what sort it is (the animal, not the laser). Think outside the box

Added places to find high-powered green lasers[edit]

I added some places to find high-powered green lasers and a picture that I took of my laser from Wicked Lasers. If anyone else has places to find green lasers be sure to add them to the section.

Thanks.

RockMancuso 00:04, 18 March 2006 (UTC)

Cyberguys.com at 800-892-1010 or www.cyberguys.com have a AAA powered green, penlight laser for about $130.

Red lasers and some green penlight lasers are on sale at most large office-supply stores like Staples, Office Depot, and Office Max.

Many sites on the Internet have lasers for sale but realize that battery power sorts the good from the bad units. You should avoid using watch batteries for power supply and many cheaper models select this limitation. Users get better performance out of AA or AAA power cells.

eBay for as low as $6 with shipping & handling already included. You can find the same effect and same type of green laser pointer that the last episode of supernatural one of the film crew members used at Papatek. — Preceding unsigned comment added by Milywang (talkcontribs) 07:04, 25 March 2011 (UTC)

Edit a link[edit]

One of the Wicked Lasers users had entered his referral code into the link to the Wicked Lasers site, which allows the user to gain points towards a future purchase whenever someone purchased a laser after clicking the link. This is abuse of the Wicked Bucks system due to the fact that the Wikipedia is public domain and someone should not benefit from the wikipedia in this way.

All i did was restore the actuall URL to the Wiked Lasers site ---Matt

Promotions?[edit]

Just curious, are you allowed to have promotions and company ads in an article? Doesn't sound right to me.

No. DieSwartzPunkt (talk) 14:55, 17 February 2011 (UTC)

Removed promotions[edit]

Removed the price-list of Wicked Lasers, Wikipedia is not for promoting individual companies and posting their price lists. Removed Link to Wicked Lasers about their record. Unfair publicity to them. —Preceding unsigned comment added by 41.245.108.189 (talk) 18:20, 9 September 2007 (UTC)

External links[edit]

Why are some external links (high powered) allowed and not others?

Well, perhaps, because many lasers sold on the Internet are not legal in the US and most other industrialized nations, as they lack any semblance of safety equipment. Seriously, there's a reason why somebody can sell a 200MW red laser for ~55$, and it's not just by using cheap labor and lead paint. The product won't have a delay, a key, an IR filter (needed on green lasers), or many of the other things a class IIIB product ought to sport. While we indeed have users in countries like China and India, it's still probably not the wisest to link to these eminently affordable and equally dangerous products.

--24.91.98.99 (talk) 06:46, 28 May 2008 (UTC)

In addition, the links that have been posted in the High-powered lasers section have tented to be links to sites whose primary purpose is to make sales. Commercial web sites are not generally considered to be appropriate for use as citations. Pzavon (talk) 02:26, 29 May 2008 (UTC)
The information on the external link Green Laser Pointer Safety Article is completely wrong and is misquoting the original study! the misinforming article states that "Ophthalmology, found that exposures of just 60 seconds to over 400mw green laser pointers can cause visible harm to the eye's retina, while the real study used "a commercially available Class 3A green laser with an average power measured at less than five milliwatts: 60 seconds to the fovea" THAT IS WRONG BY A FACTOR OF 400/5=80!
I have thus changed the external link to Green Laser Pointer Safety Article, Pzavon you are absolutely right about your worries! I can only hope nobody has come to harm aza (talk) 23:20, 5 December 2008 (UTC)

FDA[edit]

"Lasers with outputs over 5 mW need to be registered with the FDA in the USA."

Could this be the FCC? --149.217.1.6 13:46, 21 September 2006 (UTC)


no - http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?FR=1040.10

It's the FDA


and it's laser manufacturers that register products and keep sales records ? --195.137.93.171 (talk) 06:18, 9 December 2007 (UTC)
Yes, manufacturers must register their products with FDA/CDRH. Manufacturers and/or distributors must keep sales records. There are some exceptions for Class 1 products in this regard. Pzavon (talk) 01:58, 10 December 2007 (UTC)

WHAT?![edit]

Why is this page linked to from http://en.wikipedia.org/wiki/Culture_jamming#Examples_of_culture_jamming??? Please explain or remove link...

Blu-Ray is Purple / violet ?[edit]

The part about blue lasers is rather diseving. Blu-Ray and HD-DVD diodes are 405nm and thus are NOT blue, they are purple! Second because these are purple diodes and not DPSS 473nm lasers they will NOT effect the price of current blue lasers either portable or lab style. 24.15.52.4 00:53, 10 April 2007 (UTC)

Diagram would be helpful[edit]

I think it would be very helpful to add in a diagram for th part where it's talking about how green lasers and the like work. It's very confusing for someone like me who isn't some kind of laser specialist, the way it keeps using a bunch of technical names for different parts. It's extremely hard for someone like me to visualize how all this stuff works, yet the onl visual aid I get is some picture of a guy pointing a green laser at a tree. As you can imagine, that's not too helpful. So, could someone please add in a diagram on how green lasers and blue lasers work? It would be much appreciated. —The preceding unsigned comment was added by 70.240.103.43 (talk) 01:38, 1 May 2007 (UTC).

Laser Patterns[edit]

I was wondering how the laser patterns were made in laser pointers (you know, the exchangeable heads that you screw to the pointer). Watching one with a microscope revealed a citymap-like pattern, I guess that's a diffraction pattern, from what I recall from my optics lessons, but I really wonder how it works, as the produced "image" doesn't rotate when I rotate the head or slightly move it sideways, although the microscopic pattern is made of straight perpendicular lines. Could an optics specialist explain this to me (possibly in understandable words as I'm French and I'm not an optics specialist). Thanks. CyrillusMagnus 22:12, 10 June 2007 (UTC)

High-powered portable lasers[edit]

This is an article about Laser Pointers, which are, almost by definition, low power devises. In my opinion, it is not an appropriate place for a section discussing High-powered portable lasers. I propose removing that section. Comments anyone? Pzavon 01:48, 15 June 2007 (UTC)

No opinion one way or the other, but adding a fact tag to the heading is NOT the correct way to remove a section. --Tjsynkral 02:42, 15 June 2007 (UTC)
Really? Even if the whole section is what is in need of substantiation? Pzavon 03:14, 21 June 2007 (UTC)
I'm restoring the section. They are after all pointers and can fit in into this article nicely. --Amit 14:38, 1 September 2007 (UTC)
I disagree. Please explain your rationalle more clearly. Pzavon 23:50, 1 September 2007 (UTC)
I concur with Pzavon. This article is about laser pointers and the section on high-power lasers should be deleted. It is not about handheld lasers, high power lasers, or lasers in general. If it is determined that a page is needed on "handheld lasers", of which laser pointers are one type, then handheld lasers should be created. Notably, the web pages of the manufacturers of high powered handheld lasers are careful to distinguish them from laser pointers. As the article correctly indicates, laser pointers are primarily used for drawing attention to things, particularly during a presentation. That application, even implied by the name "laser pointer", requires that low enough power is used to not be harmful to the object pointed at (e.g., a screen) but also to the unprotected eyes of the audience. Laser pointers are clearly low-power lasers, and the introduction to the article should also be changed to indicate this. Finally, the brand name "wicked" has been spammed into the links many times-- even at this moment, and has now found its way into the article; it should be excised. (Wikipedia:Spam) Oskay 08:55, 3 September 2007 (UTC)

With tiny coin-cell or triple-A 30 milliwatt green lasers going for thirty dollars online, the legal definition of a laser pointer is just that, a US legal one. Class IIIB products, including serious ones with up to 200 milliwatts of power, are regularly considered laser pointers, both on certain forums and in a winking manner, by certain discount electronics importers. Many of these products fit in a pocket, and are too poorly constructed to have any legitimate application beyond casual astronomy use or perhaps engraving; certainly not fit for any sort of laboratory or field work. These things do point, however, and the media seems to also place them alongside more pedestrian Class 2 and 3A products, as evidenced by reporting around various plane scares, as well as the US government's own bulletin. Consider this a vote to keep a mention within this article. --24.91.98.99 (talk) 06:56, 28 May 2008 (UTC)

Yes. Laser pointer is not so much a function as it is a package, and even the higher power ones are used as astronomy pointers (even if never to point at a screen in a presentation-- that would be too distracting). There's no good wiki article to discuss small handheld lasers but this one. "Laser pointers" are what they're universally called on the web, and it's what they should be referrenced as, on Wikipedia. Of course the article can do as much explaining as you like about what's useful for what. SBHarris 01:49, 26 May 2010 (UTC)

2000s fad?[edit]

Should there not be a reference to the early 2000s fad with laser pointers? You know... when teens everywhere always pointed them at everything and everyone 24/7?142.176.111.29 02:51, 20 July 2007 (UTC)

I don't recall laser pointers ever being a "fad". Not in the way chicken feathers and skinny jeans are/were, anyway. CA Jim (talk) 10:36, 8 January 2012 (UTC)
I remember them being a fad, in fact attempting to look up that fad is what brought me to this page. There were a few years in the early 2000s when any screen with teenagers in front of it had several laser dots tracking all over it, at least during the intro of whatever was showing or parts that they found boring.Beorik (talk) 22:20, 16 December 2013 (UTC)
Also here's an article I found from 1999. http://newsok.com/laser-pointer-fad-spurs-laws/article/2639173 Beorik (talk) 22:23, 16 December 2013 (UTC)
There was definitely a laser pointer fad, however I remember it being from around 1997-1999. The reason I'm so sure of the year is because I was in middle school when it happened and I had a couple of them myself. It could be that it just caught on earlier in my area(VA) than in others. And I also stumbled onto this page by searching "Laser Pointer Fad." — Preceding unsigned comment added by 74.98.171.246 (talk) 13:12, 28 September 2014 (UTC)

Unfair bias[edit]

Just to point out that they, like guns, legal to own in the US are dangerous only when placed in the wrong hands. Just because this writer does not happen to be enthusiastic about laser devices dosn't mean he/she can start spreading bad press about them. This is an encyclopedia, not a blog. section and comment added 2 September 2007 by 86.145.122.216

Please be more specific. Which section, which editor, are you talking about? Pzavon 19:33, 2 September 2007 (UTC)

Re: Redundant information[edit]

Pzavon, regarding "I can't find this infomration [sic] provided elsewhere in the article. Please use discussion page to show me" -- you can find the information you readded, from the article, in the "Types of laser pointer" chapter. Search for this sentence: "For the same optical power, the green laser will seem brighter than other colors because the human eye is most sensitive in the green area of spectrum (for low light levels), with sensitivity decreasing as colors become redder or bluer." --Bisqwit (talk) 18:52, 18 February 2008 (UTC)

Is any output power limitation exist for Europe?[edit]

Is any output power limitation exist in Europian laws for public sell of laser pointer? Mahdig (talk) 20:23, 2 March 2008 (UTC)

That may depend on what you mean by "limitation in European Law." EN60825, based on IEC60825, indicates what is acceptable beam power for extended or momentary optical or skin exposure to the beam. Compliance with EN60825 is required for complaince with other standards that must be met to market within the EU. The result is an indirect limitation on the power of laser pointers. Pzavon (talk) 22:04, 2 March 2008 (UTC)
I think the standard mentioned by Pzavon aims to limit sale of laser pointers to Class 2 throughout the EEC, though enforcement is down to individual countries. In the UK the Trading Standards Authorities have been urged to use their existing powers to enforce the limitation. --Brian R Hunter (talk) 11:37, 9 March 2008 (UTC)
Class 3 is forbidden to possess in Switzerland, there was a case recently with a tram driver getting pointed at by a green laser. 178.38.124.126 (talk) 08:20, 18 March 2015 (UTC)

Power limitations in the US[edit]

Mahdig is asking what specific paragraph in the law bans the use of a 3B laser as a laser pointer. The regulations are not that specific. They were written before laser pointers were developed. They establish laser classes based on the potential for injury to eye or to skin. Since all lasers manufactured or marketed un the US must be registered with the FDA, the FDA has a say in uses that are acceptable and those that are not. A laser that is Class 3B simply is not acceptable to FDA for use as a pointer. FDA has US Customs intercept such items and prevent their entry to the US market. If made in the US, the registration process results in FDA preventing their being marketed. But you will NOT find a paragraph anywhere in the regulations (which date for about 1971) that even use the term "laser pointer" let along address what laser powers are acceptable and what are not. Pzavon (talk) 04:30, 4 March 2008 (UTC)

only exceptionss stated in 21CFR1040.10(a)(1) and (2) require registeration which does not include end-user products like laser pointer.Mahdig (talk) 12:35, 6 March 2008 (UTC)
I am not sure I fully understand your statement, above.
ALL lasers offered in commerce in the US are subject to 21CFR1040.10, including end-user products. This is a registration of a model or type, not of each individual laser that may be offered in commerce, although annual production numbers must be reported to FDA. The requirement for registering falls on the manufacturer or importer, not on the end-user. If you build your own laser for your own use you are not subject to that regulation, but if you sell, loan or give it to someone else, the FDA considers that as being "offered in commerce" and considers that their regulations apply. Pzavon (talk) 03:01, 7 March 2008 (UTC)

I know that ALL laser products offered in commerce in the US are subject to 21CFR1040.10, however the registration as mentioned in 1040.10(a)(3) is required for exceptions stated in 1040.10(a)(1) and (2). FDA accession Number I have seen on a foreign laser pointer package are because of another laws.

Not quite the case. The exceptions at 1040.10(a)(1) and (a)(2) exempt components of laser products, but the laser product itself (as a whole) is covered. 1040.10(a)(3) is not connected to those two exceptions for components. Since the process of Registering a laser product amounts to describing how the product complies with all the requirements of 1040.10, for practical purposes 1040.10(a)(3) is not an exception but a universal requirement for laser products offered in the US market. Have you ever tried to market a laser-containing product in the US without doing that? Your product will not be on the market for long. Pzavon (talk) 23:12, 10 May 2008 (UTC)

removal of warning notice picture[edit]

I am unclear as to why this change was made to remove the warning notice image. Was there a problem with it? It seemed a useful picture to me. --Brian R Hunter (talk) 11:53, 21 April 2008 (UTC)

Outdated Classes[edit]

This article is still using the old laser classes (I, II, IIa, etc..) rather than the new classes implemented in 2002 (1, 1M, 2, 2M etc...). I would change them myself, except that I can't find the mW cutoffs for the new classes. Anyone who can fix the classes should please do so. J0lt C0la (talk) 23:05, 15 May 2008 (UTC)

Depending on where you are in the world, Classes I, II, IIa, etc. may or 'may not be outdated. The newer classification is certainly in use in Europe, but the older system is still used in the US regulatory standards "owned" by the FDA, and is only an appendix in the ANSI standard on Laser safety. What I see is the article using the particular class names appropriate to the location being discussed in particular paragraphs. Pzavon (talk) 01:27, 16 May 2008 (UTC)

Canadian regulation[edit]

Looks like Canada does have some regulations that could apply under the banner of demonstration lasers, but the scope is so narrow that it would be trivial for an importer to avoid. —Preceding unsigned comment added by 99.224.87.20 (talk) 04:04, 10 June 2008 (UTC)

Rayleigh scattering[edit]

There is a "citation needed" at the claim that Rayleigh scattering can be seen. I just did some research on Rayleigh scattering in air; I added some content to Rayleigh scattering. The bottom line is that at atmospheric pressure, Rayleigh scattering at 532 nm is about 10^-5 per meter. A 1 mW green laser has a luminous power of 0.6 lumen, and hence rayleigh scattering is 6e-6 lumen per meter over a 2 mm beam (a 0.002 m2 surface). The beam will hence appear roughly as if it were illuminated at 6e-6/0.002 = 3 millilux, which is comparable to a moonless clear night sky. (I should actually correct the number to deal with the angular distribution). A dark-adapted eye should be able to see this, especially when you look along the beam, which multiplies the apparent brightness by 1/sin(theta) where theta=0 deg means you look paralell to the beam.

Now I'm not sure how to turn this original research into verifiable encyclopedic content. Han-Kwang (t) 10:45, 27 June 2008 (UTC)

I know it's been a while since you asked this, but it doesn't matter whether you can see it or anyone else can see it. To be included in the article it requires a valid citation. If it is included uncited and remains unchallenged, then it is generally regarded as accepted by concensus. However, this doesn't prevent some bloody minded editor challenging it and removing it as uncited. DieSwartzPunkt (talk) 15:00, 17 February 2011 (UTC)
Except it's NOT Rayleigh scattering. With such an oblique angle what you would instead be seeing is scattering from dust/moisture in the air which is not Rayleigh scattering. Ergzay (talk) 20:27, 15 March 2016 (UTC)

Canada[edit]

"Canada

No regulations controlling the importation and sale of laser pointers have been established in Canada to date. There are no records of high powered lasers being confiscated, although they should not be abused."

Saying they should not be abused is very subjective... needs reviewing or deleting.

86.4.76.91 (talk) 18:22, 11 September 2008 (UTC)

Types of Laser Pointers[edit]

End of section Types of Laser Pointers contains malicious edits. Reedits needed. —Preceding unsigned comment added by Thelegato (talkcontribs) 00:37, 14 October 2008 (UTC)

Yes, indeed it did, but the solution is to revert those edits, and that has been done. Learning to revert an edit should be easy for anyone who is able to leave a note as above. I commend that process to anyone who does not yet know how. Just look at the history tab, and either select the UNDO link for a single bad edit or open the edit previous to the bad one, select the EDIT tab and then save without other changes. Be sure to supply an Edit Summary. Pzavon (talk) 03:10, 14 October 2008 (UTC)

Infrared Pointers?[edit]

Okay, what's the deal with these IR laser pointers I've seen advertised on the web? Uh? Should there be any mention of them in the article? Kyprosサマ (talk) 16:15, 12 December 2008 (UTC)

I believe this article is, and ought to be, about low power, visible laser pointers such as are used in lectures. Those IR lasers are not usable in that context, and are much higher power. They are for target acquisition and other specialist purposes and should not be acquired or used by the untrained public. We have had others occasionally put in a paragraph about so-called high power laser pointers. I don't think the topic belongs here. Pzavon (talk) 01:21, 13 December 2008 (UTC)
On the contrary, it does-- else where to put it? See below. SBHarris 01:26, 26 May 2010 (UTC)

Danger, Will Robinson[edit]

I've just added a few paragraphs about the new generation of laser "pointers" based on high-power IR diode-pumped KTP doubler +/-YAG technology (DPSS lasers). These things look just like the standard 2 AAA pocket laser pointers, but can have power outputs of up to 300 mW (green) and 120 mW (violet). What makes them especially dangerous is the IR component is left in, since it's hard to get out (lack of heat sink fins on a pocket pointer), and also it adds to spectacular "effects" like lighting matches and popping dark balloons (generally more a function of the IR than the visible, mainly due to more shear IR power). These things uniformly come from China.

It isn't always easy for the consumer to tell if they have one of these things, particularly in medium power devices. In the high power ones, they always have a big IR pump component in the beam, from the "pointer" package (from what I've seen). That makes this a very appropriate topic to put here in this article, because it's the "pointer" package (defined by cost and size, not by power) which is likely to result in the IR problem. Not only is the IR truly dangerous (particularly if your glasses only filter out the visible part!), but it's not well-publicised. This tech is too new, at these prices. Wikipedia to the rescue, in that case. It's not so much a problem with professional or lab grade lasers, even if they work on the same principle. It's a problem of the brighter "laser pointers."

Oh, yeah-- with a 300 mW green laser, you can see the beam at any time from any direction in any condition. It must be Raleigh scattering. If you watch carefully, you can see little sparkles in the beam that come from occasional dust motes and even water droplets in fog, but the background to that is a very "thick" homogenous scatter, which pretty clearly is from the air itself, not anything suspended in it. SBHarris 01:40, 26 May 2010 (UTC)

Re: UK Laws[edit]

Anything above 1 mW is illegal for sale in the UK (import is unrestricted).

Just wondering if that is still true or have they restricted imports? --84.13.35.183 (talk) 14:26, 3 July 2011 (UTC)

Why is laser-light superior to absolutely safe non-laser light?[edit]

Please correct me if it's not true that all that is needed for a light-pointer to work is DIRECTIONAL coherence; and if it's not true that there's no need for the light to be PHASE coherent (all troughs and all valleys of all light-waves lined up in synch) and COLOR coherent (composed of only one wavelength of light). If a beam of light has directional coherence only, and is composed of more than one color of light and the waves are not all phase-synched, won't that light shine just as brightly (but with absolute safety should it hit a human eye) on a distant pinpoint as a potentially-blinding laser-beam would shine? How is it BETTER to use a product that can blind people instead of a product that CAN'T blind people, when all you want to do is appear to be way-out cool by pointing at your PowerPoint graphs with a light-beam instead of a yard-stick? The article seems incomplete to me in omitting these points, for there must be a rationale for the existence of such dangerous technology.76.8.67.2 (talk) 02:10, 27 November 2011 (UTC)Christopher L. Simpson

The real crux of a "light pointer" is its ability to project a small, bright spot some distance away. Small, bright spots are harmful to eyes (although this is hugely over-played for laser pointers), no matter how you make them. If you compare to a pre-laser pointer, they often projected an image of an arrow that was a few inches across when projected onto a screen in a typical lecture theatre. This might have the same total flux (in lumens), but being a larger projected image the luminous intensity (in candela) is much less. Hazard is usually based on intensity, because the hazard is based on accidental exposure of some part of the total flux through a narrow physical gap. An "eyeful of projected arrow" is a small fraction of that arrow. An "eyeful of laser pointer dot" is probably all of it.
If you want to make lecture pointers safer, the solution would be (IMHO) to make the projected images larger. These need a certain total flux to make them visible, but a larger image can do so with less intensity. There's also the perceptual effect that a large dim pointer is more obvious than a spot, so a spot may need far more flux just to be noticeable. The two effects combine to require a spot that's super-intense.
A further reason for the popularity of laser pointers is that they're physically small diameter, when the old projector pointers weren't anywhere near pocket sized. Projecting useful pointer images needs either a coherent source with low divergence (i.e. a laser) or a large objective lens. You need at least one of these.
As to your other points about coherence, then I'd broadly agree - but the monochromaticity is an incidental side-effect that not only comes for free, it would cost more to get rid of it. Phase coherence also isn't particularly good in laser pointers. If you're using laser diodes as a source for schoolroom interference experiments, it's common to find that a laser pointer won't do it and you fall back onto a HeNe in a 6" tube. Andy Dingley (talk) 12:11, 27 November 2011 (UTC)

External links modified[edit]

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Deleted section on aiming laser pointers at the sky for astronomy[edit]

Laser pointers are not aimed at the sky for pointing in astronomy. This is both dangerous and illegal and is not performed. Anyone doing such a thing would be breaking the law in many countries. Even if it was not illegal this is dangerous for pilots that might fly overhead. Ergzay (talk) 20:23, 15 March 2016 (UTC)

You seem pretty quick to allege that pointing laser towards the sky is illegal without providing any proof. A quick Google search suggests that astronomers do indeed use green laser pointers (http://www.ncbi.nlm.nih.gov/pubmed/20035242). Furthermore, the chances of someone accidentally pointing at an aircraft is astronomical (no pun intended) unless if said person is near an airport. In the UK individuals and groups are allowed to direct light sources towards the sky if they do it outside restricted areas and in a safe and responsible manner. 202.73.1.98 (talk) 09:13, 15 June 2016 (UTC)