What the heck is this thing?

[Marks256]

I just bought an assorted pack of 100 LEDs from Jameco. A small, but significant percentage of these were these weird thing that look like this;

**broken link removed**

I had to draw a diagram of it too, since the resolution of the actual image is so bad. What the heck is it? I sent power to it, but i couldn't see anything. Is it infrared? What is it?

 

[dknguyen]

Looks like a fluorescent light?

 

[Marks256]

It can't be. I send power to it, but nothing. I don't think it is infrared, because i just took a picture of it with my digital camera, and it didn't glow. I want to know what it is. Maybe it is useful?

 

[hjames]

What's the forward voltage on it? Infrared - especially deep IR 880 and longer is usually filtered out. They'll have a voltage drop of ~1.5V or less.

 

[Marks256]

How do i figure that out? Do i just connect it to a power source, and a voltmeter?

 

[freeskier89]

It looks like a normal rectangular led to me. My guess is that it is IR. I have seen some leds that look really really similar to that picture used for optointerupters in normal non-optical(with the ball) mice.

 

[Marks256]

That is what i am thinking that it is. It looks just like one to me. I am guessing that they aren't very powerful?

 

[hjames]

How do i figure that out? Do i just connect it to a power source, and a voltmeter?

Put ~20mA across it and check with the voltmeter

 

[HarveyH42]

Mark, was just playing with the same part. Its an irLED, but the cool part, is that it works as a detector as well. Notice a small bump for a lens on one face?
These are what's under the black plastic of the opto interupter in my slot machine I'm trying to fix up. Anyway, as a detector you get about .6 volts when they are about an inch apart. Also might be same/similar to what's in an optical mouse (will take a close look nextime I open mine to clean it).

Yeah, as ane emiter they aren't the brightest. Looked at it through the digital camera, only a small dot looking staight at it. Didn't try it in a dark room, but don't think it'll illuminate much.

 

[Marks256]

Cool, thanks, HarveyH42.

--OFF TOPIC: How is that hurricane down there?--

Anyways, later on today i will play around with them some more. Yes, i am 100% sure that these things are the things that are in mice. Thanks guys(and gals?).

 

[Hero999]

I know they're infrared LEDs I've got some in my jusnk box, you can get IR transistors and diodes in the same package.

 

[jakester]

diodes

they look identical to ones ive replaced in early sharp videos , a pair recieve and transmit form an opticoupler between castalations on the supply tape spool the rx one is fed to the mechacon chip so if the spool stops for any reason the chip does not recieve a reset and stops the machine .