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"Red is Dead" Optical Mice LED Change
A reader sent us the
HOWTO for changing that red LED on your fancy-pants new optical mouse to blue - or, I suppose any other color. I think I'm fine with what I've got - although, the glass tops on tables does make using optical mice a pain there.
From the article: With the LED's now exposed, gently heat each side of the LED's carefully pulling on them until they are removed from the PCB. Take your time. This is actually the hardest part of the whole mod.
This shouldn't be the hardest part of the mod. Solder-removal braiding and suction solder removers are cheaply available and highly recommended. Once you remove the solder, removing the LEDs is much easier and safer. (No flying hot solder!)
Blue has a shorter wavelength than red.
The reason red LEDs are used is because they are the cheapest, as longer wavelength bandgap devices are easier to make.
The exception to this logic is infrared, since LEDs are typically used for visual indication. Infrared LEDs are useless for this purpose so manufacturers don't make nearly as many of them...
I did this on an older style Microsoft Intellimouse, using a light blue LED from Radio Shack. And they're not kidding about losing responsiveness. I couldn't play Counter-Strike anymore or any other games which required me to move the mouse quickly. The mouse would just lose tracking and the cursor would freeze on the screen. I swapped the original red LED back in, and what do you know, it works fine again.
I don't recall the URL, but about a year ago someone did a comparison of about 10 different LED colors they tried in an optical mouse, and found that red is the best. (Duhh)
Not All Who Wander Are Lost
Here's a link for the same mod with a Logitech Mouse.
www.skybusiness.com/ntanner
I've done this, and it works fine. Note that there are two Radio shack LED's that are blue, one that outputs 2600 MCD's at 4.5 volts, the other 300 at 6 volts. I used the brighter one, and have no skipping problems at all.
Radio Shack
www.christopherlewis.com
Hello,
Yes, the hosting company shut down the site temporarily. Crippled their server. Sorry guys...I tried to keep it up.
About the LED's used in this mod...
They are from superbrightleds.com (go figure huh?) hehe
You need them that bright in order for them to work properly. Hope this helps!
Please stop being lazy and Google for it yourself. The original poster is quite correct. The human eye is most sensitive to green light. Going from red (632 nm) to green (532 nm) there is an approximately fourfold increase in sensitivity. That's why green laser pointers are starting to appear, despite their cost. Novelty value, certainly, but also because a laser pointer limited to a safe power is four times more visible in green than in red.
My guess is that it is because green does not re-transmit as far in distance as red does. Red has a longer wavelength and so can travel further without absorption. You don't want your enemy to be able to see you as well, right?
The eye can resolve finer variations in contrast and brightness in green than in red, as well--hence the use of green displays in night vision scopes. Incidentally, it doesn't matter at all what colour your night vision scopes' display is from the enemy's point of view. Night vision devices are almost always passive devices that collect existing light. As long as they are properly fitted, they aren't directing any radiation--red, green, visible, invisible--outward, so there's nothing to see.
There was a study done about what would be better to use for star watching: green or red.
For amateur astronomers, red LED flashlights are available. They are used because even a fairly bright red LED is perceived as relatively dim by the eye, so your eyes don't lose their dark adaptation every time you check your star charts.
As an aside to anyone here who works with near-IR lasers...you know that a 200 mW diode laser at 670 nm (very red) looks no brighter than a 5 mW HeNe (red, 632 nm)--indeed, it looks quite a bit dimmer after all those burn spots start occluding your vision. Wavelength matters just as much as power when talking about perceived brightness.
~Idarubicin