Bored at work; neat pictures follow. *New Pics Added 3-13-07!*

DNova · #1 02-19-2007, 10:02 AM

Thought you guys might like to see a couple of interesting pictures I took last Friday and today.

These first pictures are from a standard long-life 60 watt light bulb. It came with my house and was in operation nearly 24/7 for at least 4 years. The following three images were made with a FE-SEM (Field Emission Scanning Electron Microscope). Please do not republish any of the images in this post.

This is one of the very thin filament supports (not electrified) which helps to hold up the filament. It is made of pure molybdenum which is a high-melting-point metal. This is a clean area of the support

Here's the same exact wire, but in an area where evaporated tungsten condensed. When metals evaporate in high vacuum, they tend to leave a very thin uniform film, but under (relatively) high pressures in a modern incandescent bulb, they leave a cloudy/fuzzy mess like you see here. The fuzzy stuff is of course tungsten.

Here's a highly magnified (5,000x) view of the evaporated tungsten fluff.

Next I decided to take a look at the filament of a Mag Solitaire (single cell) flashlight bulb. These are tiny bulbs if you aren't aware of them. The following two images were taken on a Nikon Stereoscope using reflected light and a 4mp digital camera attachment.

This is the filament without any power through it. The total distance between the two posts is approximately 1.5mm. The length of the coiled filament is less than 1mm. I don't know what the total uncoiled length would be.

And here it is in operation with an aging alkaline AAA. You can notice how much of the filament is NOT incandescing because of heat loss to the supports. Probably a bit less than 500 microns (.5mm) of the filament is incandescing. Perhaps a bit more would with a stronger battery.

That's it for now. I hope you found these at least a little interesting.

Ra · #2 02-19-2007, 10:18 AM

Nope !!, Not a little interesting,,

I found them very interesting !!

If you are bored in the future: Maybe you can make some pictures of a new halogen-filament and one at half-age ?? Would also be very interesting !!

Regards,

Ra.

atm · #3 02-19-2007, 10:20 AM

Awesome, thanks DNova, and welcome to CPF!

Manzerick · #4 02-19-2007, 10:21 AM

Very interesting!

abvidledUK · #5 02-19-2007, 10:29 AM

Perhaps put your CPF name across the photo's to discourage copying ?

greenlight · #6 02-19-2007, 10:31 AM

Sweet post.

It would be cool to see what different flashlight finishes look like up close.

DNova · #7 02-19-2007, 10:36 AM

Quote:

Originally Posted by Ra

Nope !!, Not a little interesting,,

I found them very interesting !!

If you are bored in the future: Maybe you can make some pictures of a new halogen-filament and one at half-age ?? Would also be very interesting !!

Regards,

Ra.

I'm glad you found them interesting

I am actually planning to take some SEM images of unused filaments versus heavily used filaments of the exact same bulb at some point in the future.

The differences will be very interesting for sure. The problem is finding a bunch of pairs of identical bulbs, one being burned out or heavily used, the other being unused.

If anyone has such pairs to donate to the cause that would be great.

DNova · #8 02-19-2007, 10:39 AM

Quote:

Originally Posted by greenlight

Sweet post.

It would be cool to see what different flashlight finishes look like up close.

Doing this would be very easy, but I can't accomodate large samples. I'd have to cut them up unless it was a really small flashlight with no electronics (or removable electronics). If anyone wants to send things for analysis I'd be happy to do it. I can identify alloys and elemental composition too.

IsaacHayes · #9 02-19-2007, 11:44 AM

I love it!!! Thanks!

Christoph · #10 02-19-2007, 11:57 AM

cool pics

send more next time you get bored.

molite · #11 02-19-2007, 12:03 PM

Very nice.
I hope you continue to get free time at work.
More pic's of anything light related would be very cool.
What other cool toys do you have at work?

65535 · #12 02-19-2007, 12:25 PM

Very awsome.

DNova · #13 02-19-2007, 02:39 PM

Quote:

Originally Posted by molite

Very nice.
I hope you continue to get free time at work.
More pic's of anything light related would be very cool.
What other cool toys do you have at work?

Thank you and everyone for your comments.

Don't worry about me getting free time at work, I promise I have plenty

I'm going to be taking some pictures of the truly tiny incandescent bulbs that old digital watches used as a backlight. I have a few examples, and man, they must be the smallest light bulbs ever made. But I only have one of them here today, so I'm going to wait until I remember to bring them all in.

If you have any specific requests I can try to fulfil them. I have access to a ready supply of liquid nitrogen and I'm thinking about breaking open a new light bulb and turning on the filament under there to see what happens. I think it'll just conduct too much electricity and not light up, so I'm going to use a fused test rig with a dead-man's switch to try it out. We'll see I guess.

Let me know if you have any ideas/requests.

Mark_Larson · #14 02-19-2007, 08:56 PM

Wow, awesome photos. And I definitely remember those tiny bulbs that were used before LED/EL lighting. Wow, these photos are really awesome.

Mike V · #15 02-21-2007, 06:09 AM

Wow.

Amazing. Thanks for posting these.

DaFABRICATA · #16 02-21-2007, 06:30 AM

I close up of an LED emitter just barely on would be really cool!

thesurefire · #17 02-21-2007, 11:50 AM

Those are really cool pictures.

Quote:

Originally Posted by DaFABRICATA

I close up of an LED emitter just barely on would be really cool!

I would also love to see that.

Thujone · #18 02-21-2007, 12:01 PM

Quote:

Originally Posted by DNova

Doing this would be very easy, but I can't accomodate large samples. I'd have to cut them up unless it was a really small flashlight with no electronics (or removable electronics). If anyone wants to send things for analysis I'd be happy to do it. I can identify alloys and elemental composition too.

Possibly you could just use the tailcap of a few flashlights if they would be small enough for you.

Thanks for the great pics.

DNova · #19 02-21-2007, 02:06 PM

Some tailcaps would probably exceed my height restriction, it all depends on their geometry. I could figure out the max dimensions if there's enough interest.

As for a barely-emitting LED die, I'll bring in a few monochrome LEDs and hopefully get some neat pictures for you. Probably Friday

DNova · #20 02-23-2007, 09:39 AM

I packed up a bunch of stuff last night to bring in today for an LED photo shoot. Luckily, I grabbed more than the first LED that looked suitable out of my pile, because it turns out that one was DEFECTIVE!! Anyways, here are the pics with some annotations. Again, please do not republish these in any way. If you want to use them just ask. These are all optical microscopy photographs.

Oops, the LED factory failed to properly attach the ball bond to the die! Or it detached before it was encapsulated in plastic. Either way, this LED never had a chance. At the top is a reflection of the die and wire due to the shape of the LED package.

Another LED (this is the LED used for the rest of these images), no power, low magnification.

Higher magnification of the same LED, with more light shining on it. It still has no power. The die itself is red and all the red light in this picture is merely reflecting off the die.

Low magnification with 5.2v + 30,000 ohms (less than .2mA through the LED).

Higher magnification with the same power parameters.

Here it is without any ambient light, and only 1,000 ohms resistance. In all these pictures the red ring around the die is just from the metal reflector cup, and is not part of the emitting surface.

Hope you guys like this batch of pictures! It was a lot harder to get decent pictures of these LEDs than I thought it would be. I played around for a while with exposure settings, positioning, and external lighting. Let me know what you think!

DaFABRICATA · #21 02-23-2007, 09:51 AM

YOU ARE THE MAN!!!!!

Illum · #22 02-23-2007, 10:21 AM

you have this kind of technology at your work place????!!!
how can you be BORED?

theres so many things worthy of being seen with that microscope of yours....you can literally find the flea on the flea on your dog...provided you have one...

where do you work?

EngrPaul · #23 02-23-2007, 10:31 AM

Cool. (I was hoping it wasn't photocopies of your butt.)

DNova · #24 02-23-2007, 10:50 AM

Thanks

Here's the bigger version of my new avatar for CPF:

B@rt · #25 02-23-2007, 10:51 AM

Impressive pics!

molite · #26 03-12-2007, 07:59 PM

Awsome again!
A newbie with something to offer CPF and Wow the senior members!
Unlike me, sucking up information and asking dumb questions.
You really make all us other newbies look bad.
Keep the pic's coming.
You've done Ican and Led so now a lazer?

liveforphysics · #27 03-12-2007, 09:56 PM

Outstanding!

These are some of the most outstanding pictures I've ever seen!

Thank you for shareing these amazing photos with us!

Manzerick · #28 03-12-2007, 10:58 PM

Wow!!

Very nice pics!!!

65535 · #29 03-12-2007, 11:16 PM

I would love to see the surface of a HID bulb where the arc is formed new and after a few hours and after death.

greenlight · #30 03-12-2007, 11:23 PM

Must be some boring job!!!

sweet avatar, too.