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Replacing The LED In An Optical Mouse? 22

Jeffv323 writes: "I was thinking the other day, what would my Logitech optical mouse look like with a superbright blue LED [?] ? I couldn't find any Web sites that had any technical specifications on how the optical sensor works, so I am not sure whether this idea might work. All the sites I did go to said the sensor was actually a small camera taking 1500 pictures a second. If this is true it seems like my idea could work." Has anyone out there replaced the LED in his optical mouse, out of necessity or curiosity? Have you found any good information about wavelength tolerances, voltages, etc? Anything that can handle a blue LED ought to have one in it, IMHO.
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Replacing The LED In An Optical Mouse?

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  • If the camera is most sensitive to red light, then maybe a white LED would do the trick, or orange. Not so cool as blue, though.
  • I could not dissagree youth you more.

    I can solder fine. Doesn't mean I need to know what a 'diode' is, or how it works.

    When I put the blue LED in my computer, you think I knew what the polarity on it was? I have no idea. Not like one leg was longer than the other or one wat notched or there were INSTRUCTIONS. Trial and error.

    If someone won't solder their mouse because they don't know hoe diodes work, how on Earth are they going to LEARN what a diode is?

  • Sure. If you know what a continuity checker is.

    All I'm saying is I was fiddling around and resoldering stuff long before I knew what a diode did.

  • That would be an Amiga 4000 I had years ago... After all, I'll only be 3902 years old in March.
  • Have a look at this page [www.riceboypage]...

    Speaks for itself.

  • Sure, only one button, but the LED's are out and I might as well replace them with some kewl blue ones. -c-
  • I made a number of repairs to the optical mouse I had with my Amiga 4000 years ago

    Is that an Amiga 4000 that you had years ago, or is it an Amiga you had 4000 years ago? ;^)

  • Probably has to do with the cameras optimal light frequency. If the camera isn't as sensitive to the blue end of the spectrum, any light bounced back from the surface will be less observable to the camera, then say, a red LED. Who knows, maybe they just presume that nobody has a red surface they'd like to use?
  • What is that reason? (seriously)

    I'd think that the responsiveness would vary depending on what surface you're using the mouse on... a blue desk? Get a red LED... a red desk? Blue LED... Additionally, they didn't specify in the article whether they had picked up a high intensity blue led or no.

    If there is a different reason for a blue LED not working as well, or my Science! is incorrect, or you know why it came with a red LED in the first place, please let me know.

  • Depends on how much current the current limiting resistor (across which some of that 5 volts will be dropped) limits the current to.
  • Warning: we have found that our blue LED actually worsened responsiveness on reflexive surfaces.

    I think that blue vs. red led is the least of our worries.
    Beware of tables that speak of themselves.

    reflexive (r-flksv)
    adj. Abbr. refl.

    1.) Directed back on itself.
    2.) Grammar.
    a) Of, relating to, or being a verb having an identical subject and direct object, as dressed in the sentence She dressed herself.
    b) Of, relating to, or being the pronoun used as the direct object of a reflexive verb, as herself in She dressed herself.
    3.) Of or relating to a reflex.
    4.) Elicited automatically; spontaneous: "a bid for . . . reflexive left-wing approval" (Marshall Delaney).

    reflective (r-flktv)
    adj. Abbr. refl.

    1.) Of, relating to, produced by, or resulting from reflection.
    2.) Capable of or producing reflection: a reflective surface.
    Characterized by or given to meditation or contemplation; thoughtful. See Synonyms at pensive.
  • There is a reason they the mouse came with a red LED to begin with....

    Yes there is: price.

    Have you ever compared red vs. blue LED prices lately? 500 to 1000% is pretty big.

    Red LEDs are also highly available in a huge number of package types. I used to use these cool Siemens LEDs (forgot the part number) that allowed you to stuff fibers down to a lens extremely close to the PN junction. For only CDN$1.05, they were a steal. You simply can't get blue LEDs in that package. If they were available, they'd cost at least $10-$15, probably more considering the lack of benefit.

    The circuitry/firmware reading the sensor, as well as the sensor itself, was probably tuned to the wavelengths output by that red LED. It also would help if the actual luminance characteristics were constant between the LEDs, which I highly doubt.

    All of that said, I've always found infrared much better for sensors, but it's much harder to debug.

    Besides, coloured lights are impressive...
  • First a blue LED, then what? Install a 20" non-functional mouse ball? Type R stickers on the sides?

    Mice and rice don't mix. :)
  • the article's interesting, but after reading:

    You have to make sure you match up your new LED's with the old LED's polarity, otherwise it will not work. We have tested to see if putting the LED in backwards will ruin your mouse. With our mouse, it did not hurt it at all.

    I gotta wonder.
    LED: Light Emitting DIODE.
    Diode. Of COURSE putting it in backwards isn't going to HURT. It's just going to break the light circuit, and not emit any light.
    The way I see it: if you need to be told not to put a diode in backwards, you shouldn't be soldering your mouse.
  • Argh... can't just cut and paste that. There's a space at the end. For your clicking pleasure: php []
  • I made a number of repairs to the optical mouse I had with my Amiga 4000 years ago; here's what I've found:

    As one other poster recommended, a soldering pencil will work better than a gun. I ended up replacing switches under the mouse buttons when I wore them out playing Populous II, and a pencil fit into tight spots on the board with more precision.

    Pay careful attention to any specs you can find on the LED; trial by error isn't something to rely on. I couldn't find any specs for my mouse, and used trial and error to work my way through a couple LED's from Radio Shack... I couldn't find any that would light brightly enough for the mouse to work. And it was a shame to pack it away after all the other mods I made...

    Good luck with your mods, and I hope you can find good specs.
  • I saw on [] a nice mouse hack with a blue LED. It is really impressive and worth a has pictures and steps along the way. Super neat. The URL is [] Have fun.

  • Blue leds are generally extremely sensitive to being put in backwards. They are even sensitive to being looked at backwards.

    See the blue led articles at the []. This quote from [] is about the Radio Shack blue LED:

    This LED would appreciate being fed 3.4 to 3.8 volts DC at 20 milliamps, and would thank you to the stars if you did not hook it up backwards. Like most LEDs using this new technology, connecting them backwards is very often fatal to them.

    Slashdot covered this site before [].

  • by Clubber Lang ( 219001 ) on Tuesday February 20, 2001 @08:47AM (#418518) Homepage
    Just wanted to point out that the article mentions using a soldering *GUN*, which should be fine in this case but generally not reccomended for electronics.

    These tips won't really be useful to people with electronics experience, but I'd rather not see anybody ruin a mouse or other electronics by making an easily avoided beginner's mistake.

    Mouse cicuitry isn't exactly the most complex stuff in the world, but when working on electronics projects it's really better to use some type of soldering pencil. Soldering guns put out waaaaay more heat then needed, and produce some pretty nasty electromagnetic fields. These two combinded can fry an IC in no time flat (shouldn't be directly soldering an IC anyways, but that's a different topic).

    Oh yeah, and DON'T use acid core solder.

    Soldering and desoldering tips []
  • by duplicate-nickname ( 87112 ) on Tuesday February 20, 2001 @04:39AM (#418519) Homepage
    Warning: we have found that our blue LED actually worsened responsiveness on reflexive surfaces.

    There is a reason they the mouse came with a red LED to begin with....

  • by Anonymous Coward on Tuesday February 20, 2001 @01:29AM (#418520)
    right away sir php here's the light mouse mod you ordered, would you like fries with that?

Houston, Tranquillity Base here. The Eagle has landed. -- Neil Armstrong