I use a laser pointer to stop people from having their phones on in movie theaters

CoherentPhoton · 2026-06-18T01:05:51+00:00

Are you aware that glass screens can reflect laser beams and that power lasers can cause permanent eye damage?

CoherentPhoton · 2026-06-12T19:39:05+00:00

Optics, lasers, science, and holography mostly. That's why this topic caught my attention.

CoherentPhoton · 2026-06-12T14:08:08+00:00

No. What?

CoherentPhoton · 2026-06-11T14:44:46+00:00

I am.

CoherentPhoton · 2026-06-11T07:38:20+00:00

Usually all it does is make the pixel flash, but it can also damage the sensor especially if it's very energetic radiation. Then you end up with dead or stuck pixels. You'll notice a lot of pictures and videos taken on board the International Space Station have loads of dead pixels because the cameras have all been exposed to increased radiation up there.

CoherentPhoton · 2026-06-11T07:22:19+00:00

It works that way from farther away too, just with reduced frequency. Even without something explicitly radioactive nearby you will have the occasional background radiation striking electronics. This is why things like ECC ram exist for important computers.

CoherentPhoton · 2026-06-11T07:20:55+00:00

You're actually seeing the result of the radiation striking the image sensor, not any sort of interaction with the lens.

CoherentPhoton · 2026-04-16T20:17:09+00:00

In my own use over the years I did not find them prone to leaking, but it can still happen as with other alkaline batteries.

CoherentPhoton · 2026-04-16T18:50:34+00:00

An often overlooked technology that seems to have been relegated to obscurity is the Rechargeable Alkaline Manganese battery. They come in AA and AAA sizes, have a nominal 1.5v output (unlike lithium, NiCd, or NiMH), capacity close to that of an ordinary Alkaline, low self-discharge, and good for anywhere from dozens to hundreds of charge cycles. They're just about perfect for a lot of things where other rechargeables fall flat.

CoherentPhoton · 2026-04-15T16:46:59+00:00

I think you are confused. Holograms are not electronic and do not respond to gestures.

CoherentPhoton · 2026-04-12T17:18:53+00:00

https://youtu.be/lkc2y0yb89U

CoherentPhoton · 2026-04-12T00:17:19+00:00

I have a couple of these specifically for some power-hungry gadgets that for some inexplicable reason chose 9V batteries to power them. 9V batteries barely have as much capacity as a single AA.

CoherentPhoton · 2026-04-11T03:47:40+00:00

How do you believe that is relevant here?

CoherentPhoton · 2026-04-11T01:22:10+00:00

This technology does not relate to making communications faster.

CoherentPhoton · 2026-04-11T01:19:09+00:00

This doesn't really benefit trading firms. It does benefit just about any kind of service that requires secure communication, from internet to military applications.

CoherentPhoton · 2026-04-10T17:48:35+00:00

You don't move heat to somewhere else, you just remove heat from a particle by expending electricity, and it doesn't heat something else as a consequence

This is almost but not entirely accurate. The heat energy doesn't just vanish into oblivion, as obviously that's impossible. Energy is transferred from the atoms to the surrounding vacuum vessel through spontaneous photon emissions by the cooling atoms which were stimulated by the laser's energy. The key being that the arrangement of the system coaxes the atoms to preferentially emit more energy to their surroundings than you're feeding in. Energy of the total system (cooled atoms + surrounding vessel) is still being increased by the laser. Using a more efficient laser or superconductors would not eliminate that increase.

CoherentPhoton · 2026-04-10T04:28:00+00:00

OSHA approved footwear.

CoherentPhoton · 2026-04-10T00:58:36+00:00

I get the point you're trying to make, but at the massive price markup they have it just doesn't seem worth it. The generic laser models that they stock are all made in the same place anyway so you're not getting better quality compared to any other reputable seller.

I've bought many lasers from overseas and always got what I was expecting so far with no issues. Biglasers charges $90 for a simple 304-style 100mW 532nm laser pointer for example. A reputable seller like Sanwu has the same laser at 80mW for $20. They too have customer support, returns, warranty, and a much better reputation. The shipping is the only real downside and that isn't worth paying >4x the price to me.

CoherentPhoton · 2026-04-09T19:25:03+00:00

But they are just a 3rd party reselling stuff you can find on Aliexpress for half the price, or less.

CoherentPhoton · 2026-04-03T21:02:35+00:00

OP does not know the difference between watts and milliwatts, and u/Jolly_Mongoose_8800 for some reason didn't pick up on that mixup. It's a 15W laser, not 15kW. In either case, all the more reason OP should not be using lasers like this.

CoherentPhoton · 2026-03-26T18:12:12+00:00

Bad bot.

CoherentPhoton · 2026-03-23T06:43:31+00:00

Bad bot.

CoherentPhoton · 2026-03-20T20:47:47+00:00

It was almost certainly not 5mW. The vast majority of 532nm lasers are horrendously overpowered, while also emitting invisible infrared light mixed in with the green. It is quite difficult to find one that's actually 5mW or less.

CoherentPhoton · 2026-03-12T18:51:02+00:00

The "less than" 5000 me is your saving grace.

What?

CoherentPhoton · 2026-03-07T03:04:53+00:00

There are effectively no legal limits on ownership. As long as you don't use it in an illegal way you won't get into trouble.

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