Is the laser in the Mighty Mouse dangerous?

[Luba]

I was standing next to a colleague who was seated and he flipped over his Mighty Mouse which momentarily shined in my eyes. The laser shuts off if you turn over the mouse, but he flipped it over quickly so the laser didn't get a chance to shut off.

 

[gr8tfly]

The laser is infrared, so even if it were on, you wouldn't notice. It also isn't aimed "out" of the mouse, but at a angle (it has to reflect back into the IR sensor). But, anyway, it does shut off as soon as there is no surface detected, so no worries. (And, as mentioned by spinnerlys, it's low power.)

(If you're talking about the green light, that's just a power and pairing indicator.)

 

[spinnerlys]

No, it's not a Type 1 Laser as in optical drives.

It would be quite hazardous to include a dangerous laser into an open device like a mouse.
There would be lawsuit after lawsuit.

 

[Luba]

Thanks for responding to my question!

 

[Luba]

Oh I myself have the Logitech mouse that you can use on glass using what they called Darkfield (or something like that). Do you guys know how they make it work even on a clear glass surface?

 

[TuffLuffJimmy]

A laser is just light pointed in one direction...

Oh I myself have the Logitech mouse that you can use on glass using what they called Darkfield (or something like that). Do you guys know how they make it work even on a clear glass surface?

They use a wavelength that bounces off clear glass, maybe. I don't know.

 

[gr8tfly]

A laser is just light pointed in one direction...

No, it's coherent (same phase), virtually monochromatic, light. You can simulate a laser beam by collimating normal light using lenses and apertures, but you would not have laser light.

 

[TuffLuffJimmy]

No, it's coherent (same phase), virtually monochromatic, light. You can simulate a laser beam by collimating normal light using lenses and apertures, but you would not have laser light.

So it's a directed single wavelength. Mea cupla, I didn't realize we were getting into semantics.

 

[gr8tfly]

So it's a directed single wavelength. Mea cupla, I didn't realize we were getting into semantics.

Naw, didn't really mean to hijack the thread for semantics. But, there are SO many technical fallacies running 'round the net, I feel it's important to nip them in the bud. This thread itself is an example - if we didn't properly and accurately address the OP's question, the next thing we'll see is some movement to "ban those dangerous laser mice". It'd end up like the "dangerous radiation from cell phones" threads mixing up ionizing radiation (like x-rays) with non-ionizing electromagnetic radiation at lower energies and frequencies, i.e. microwaves.

Anyway, back to the regularly scheduled thread in progress... 😉

 

[Makosuke]

Don't feel too bad--as a physics major, I was going to correct the semantics on what makes a laser a bit different from a flashlight, too.

To add a bit of info, a bright enough IR laser, even though you can't see it with your eye, could of course be dangerous. I don't know what the actual output of a laser on a mouse is, but it could certainly be bright enough that were you to stick the thing against your eye at the "right" angle and stare into it for a while would cause some damage to the retina. There is some minor added danger, since you don't really know when you're looking right into it--you can't see the light, after all. This is, presumably, why my Logitech laser mouse came with a little warning not to leave it sitting upside down or stare into the detector hole when it's on.

As for practical use, of course, no, it's perfectly safe--you would have to really work at it to damage your eyes.

 

[AndyMoore]

As for practical use, of course, no, it's perfectly safe--you would have to really work at it to damage your eyes.

However, don't leave the MM near any cheese. 😉

 

[Erasmus]

No, it's not a Type 1 Laser as in optical drives.

Type 1 lasers are harmless.
Type 2 and 3a lasers are harmless, unless you do something incredibly stupid, like stare at it continuously, holding your eye open to stop yourself from blinking, or something only very stupid like focus them in your eye with a magnifying glass.
Only type 3b and 4 lasers are likely to damage your eye, and only class 4 lasers burn things.

The laser in the mighty mouse would be a class 1 laser, ie. completely safe. It is also divergent, mostly ruining the characteristics of a laser. The only benefit I can see of using a laser is the added sensitivity gained from interference effects on the (mouse pad) surface.

P.S. Infrared light does not penetrate the lens of your eye, so the worst that can happen with large exposures to this kind of radiation is cataracts. Well, assuming it's not class 4, where all bets are off.