The LED. You may not have heard of it, but you've seen it. Light Emitting Diode. That's what scientists & techies call them.
They've been around for years, and you probably take them for granted. You probably know them as the dim red, yellow or putrid green lights in household appliances, stereos, computers, car dashboards, telephones, and toys.
This museum is here to pay homage to the lowly LED and to give you a look into the LED's past.
Showcased in our exhibits are examples of breakthrough LED (Light Emitting Diode) technology. Some of this technology is about sixty years old, while other important breakthroughs, such as single-chip white, blue, and even shortwave ultraviolet, have occured within just the last several years. On the bottom of this page, a short list will be provided of LEDs important to the Museum but which we do not have.
If anybody knows where these specific specimens or examples of these specific LED types can be found, please leave a message for the Museum Curator.
A list of acknowledgements also appears near the bottom of this page.
GUESS THE DIODE!
Is this a Germanium radio diode or LED?
The answer is somewhere in the Museum exhibits. Hint Not every item pictured in this game will be an LED.
Last updated: 05-29-07
The LED is older than is commonly believed! This link offers up some rather unusual evidence.
Furnished by a website fan, thank you!!!
Nick Holonyak Jr. invented the first practical visible-spectrum LED back in 1962.
Holonyak is currently the John Bardeen Endowed Chair in Electrical and Computer Engineering and Physics at the University of Illinois at Urbana-Champaign.
Mr. Holonyak has been honoured: please see this link for more information about this.
06-10-03 I received a link from somebody a few days ago, and this link says that BLUE SiC LEDs were really discovered in 1861!!! That's around 100 years before the first red LEDs started showing up!
In early May 2003, I finally got a LedTronics L200CWGB6-100 blue-green LED that needs 11 volts and was rolled out in 1993!
The original price lists have also become available for some of the early GE, Monsanto, and possibly some Texas Instruments LEDs; all from the 1960s and 1970s. These will be posted with the appropriate LEDs as time & webspace permits.
Exhibits will be added at irregular intervals until all relevant technology is covered, or until there are no more specimens of original breakthrough technology to put on display.
Due to rapid growth, this website has CHANGED to make it easier to use.
Follow this timeline to access our exhibits. For a truly educational experience, start at the beginning, the 1960s. However you may start with any year and jump around to any other at will.
Zinc selenide (ZnSe) blue LED (early-mid 1990s; supposedly stopped in the experimental stage when GaN came into common use)
Organic and/or polymer LED
Yellow, amber, or orange InGaN or GaN LED
Please leave me a message if you have or know where I can obtain a specimen of any LED mentioned above.
The specimens are strictly for use with The Virtual LED Museum, and will not be sold or given away.
HAVE YOU SEEN ME? I am a 6977 vacuum tube, a low voltage indicator lamp that was the immediate predecessor to the visible light LED. I am about twice the
length of a common NE-2 neon bulb, and I think I glow green. :-)
Radio collectors would be most likely to have me, because I function well as a substitute for the battery triodes.
Although this is officially the LED Museum, items such as this have a direct link to the LED and are desirable in that regard.
(Update 02-02-06): I have just purchased two of these from Ebay; expect to see them on this web page or on one of the 1960s web pages within the next couple of weeks!!! These are Mullard DM160 vacuum tubes, but they are electrically and functionally identical to 6977 vacuum tubes.
The first set of photographs on this site were taken with a Jam Cam low-res digital camera. Photographs taken after August 1 2000 were shot with a Polaroid PDC-700 digital camera and an achromatic eyepiece lens from a pair of old binoculars.
Over time, most specimens will be rephotographed with the new camera.
Camera specifications relevant to this project:
CCD: 0.8 megapixels (810,000 elements)
Lens: Multiple element achromat, combination of air & cement gap. Focal length approximately 0.8"
Color: 24-bit, firmware interpolated
Resolution: 1024x768 - most closeups require substantial cropping.
Lighting: Incandescent, white LED, xenon flashtube.
Viewfinder: Live LCD, live NTSC video.
My faithful old Polaroid camera finally died after having taken tens of thousands of pictures, so I went out and got a new camera.
Effective as of 04-02, most new pictures on this site will be taken with a Nikon Coolpix 775 digital camera. This camera has three times the resolution of my old Polaroid, so product photos and other images should come out substantially better.
(Camera took its own self-portrait through a mirror, so it didn't come out well)
The Nikon camera pooped out in late-October 2006; it was replaced with a Canon PowerShot G3 that a fan of this website sent!
ACKNOWLEDGMENTS
Don Klipstein (http://www.misty.com/~don/index.htm) was instrumental in getting this project off the ground, mainly by providing samples of LED technology which I could either not find myself or could not afford to purchase myself.
Additional acknowledgments go out to the following people:
LED Museum logo, concept and execution copyright (C) 2000 Craig S Johnson.
Except for strictly educational purposes, please ask before reproducing or retransmitting any of this site's content.
All photographs (C) 1999 to 2020 Craig S Johnson. These may be used privately, but please ask before posting them publically.
This page is a frame from a website. If you arrived on this page through an outside link,you can get the "full meal deal" by clicking here.
These are Mullard DM160 vacuum tubes, but they are electrically and functionally identical to 6977 vacuum tubes.
