Radio Shack # 276-0027 Green High-Flux ("spider") LED, $2.29
Purchased 03-22-09, tested on 03-26-09
This is a green (GaN) LED in a four-lead high-flux ("spider") epoxy package.
Beam photograph on the test target at ~12".
Measures 680mcd on a Meterman LM631 (now Amprobe LM631A) light meter.
This is a wide viewing angle LED (130°), and if I've told you once, I've told you 31,054,500 times:
Wider viewing angles always, ALWAYS, ALWAYS equal lower mcd values!!!
Unable to measure Vf due to how my LED test set was constructed.
Spectrographic analysis of this LED.
USB2000 Spectrometer graciously donated by P.L.
Nichia flat (rectangular) green LED (NSPGF50AS)
Received 12-24-07, tested 12-29-07
This is a newer model (~December 2007) Nichia NSPGF50AS green LED. It comes in a water-clear epoxy case and emits radiation peaking at 520.9nm in the green region of the spectrum.
The LED has a dual-bond construction; and is Rank GV (tint rank "G", intensity rank "V").
Measures 2,050mcd at a drive current of 19.28mA.
Vf (forward voltage) is 2.902 volts.
Viewing angle is avertised at 115° x 125°
This is a wide-angle LED, and if I've told you once, I've told you a billion times:
Wider viewing angles always, always, ALWAYS equal lower mcd values!!!!!!!!!
Spectrographic analysis of this LED.
Nichia 5mm green LED (NSPG520AS)
Received 12-24-07, tested 12-27-07
This is a newer model (~December 2007) Nichia NSPG520AS 5mm green LED. It comes in a water-clear epoxy case and emits radiation peaking at 525nm in the green region of the spectrum.
The LED has a dual-bond construction; and is Rank GU (tint rank "G", intensity rank "U").
Measures 6,710mcd at a drive current of 19.28mA.
Vf (forward voltage) is 2.767 volts.
Viewing angle is avertised at 45°
This is a wide-angle LED, and if I've told you once, I've told you a billion times:
Wider viewing angles always, always, ALWAYS equal lower mcd values!!!!!!!!!
Spectrographic analysis of this LED.
Nichia 5mm green LED (NSPG510AS)
Received 12-24-07, tested 12-25-07
This is a newer model (~December 2007) Nichia NSPG510AS 5mm green LED. It comes in a water-clear epoxy case and emits radiation peaking at 515-525nm in the green region of the spectrum.
The LED has a dual-bond construction; and is Rank GU (tint rank "G", intensity rank "U").
Measures 15,360mcd at a drive current of 19.28mA.
Vf (forward voltage) is 2.947 volts.
Viewing angle is avertised at 30°
This is a moderately wide-angle LED, and if I've told you once, I've told you a million times:
Wider viewing angles always, always, ALWAYS equal lower mcd values!!!!!!!!!
Spectrographic analysis of this LED.
http://www.ledsales.com.au..., Nichia 3mm oval green LED (NSPG346CST), retail AU 60¢ (US 55¢)
Received 11-05-07, tested 11-09-07
This is a 3mm oval LED in a diffused, green-tinted epoxy case. It produces a very wide, very smooth beam. The beam is typical for a diffused lens LED lamp.
It is a Nichia NSPG346CST "super oval" green LED.
Measures 2,050mcd at a drive current of 19.28mA.
Viewing angle is avertised at 110° by 50°
This is a very wide-angle LED; it also has a diffused lens, and if I've told you once, I've told you a million times:
Wider viewing angles always, always, ALWAYS equal lower mcd values!!!!!!!!!
Spectrographic analysis of this LED.
http://www.ledsales.com.au..., Agilent green LED (part # not available), retail AU 40¢ (US 37¢)
Received 11-05-07, tested 11-07-07
This is a 5mm round LED in a water-clear epoxy case. It produces a wide, (fairly) smooth, mainly circular beam with a very slightly brighter ring near the center. The beam is smoother than usual for a nonphosphor LED lamp.
Measures 5,360mcd at a drive current of 19.28mA.
Viewing angle appears to be 30-35°
This is a fairly wide-angle LED, and if I've told you once, I've told you a million times:
Wider viewing angles always, always, ALWAYS equal lower mcd values!!!!!!!!!
Spectrographic analysis of this LED.
LEDTronics, aqua-green LED, LD200-0AG-15D
Received & tested 05-19-07
This is a 5mm round LED in a water-clear epoxy case. It produces a circular beam with a dimmer ring inside the bright outer ring and a brighter hotspot inside of that. This is a perfectly normal beam configuration for a non-phosphor LED, and is nothing whatsoever to be concerned about.
This LED was in a press release I received via email on 05-17-07. I requested the LEDs for testing at that time, and received them less than two days later.
Measures 35,000mcd at a drive current of 19.28mA.
Viewing angle is advertised as 15°.
Spectrographic analysis of this LED.
USB2000 spectrometer graciously donated by P.L.
LEDs International, green super flux LED, L1SFWAB35
Received 02-20-07, tested 02-24-07
This is a super flux ("spider") LED in a water-clear epoxy case. It produces a mainly circular beam with an unusually smooth profile for a non-phosphor lamp. Since this is a wide viewing angle LED, the smooth beam was not at all unexpected - most wide-angle LEDs will produce smooth beams.
The visible color tint to this LED is slightly but noticeably more whitish than many other InGaN green LEDs.
It isn't obnoxious or anything, just noticeable.
Measures 9,440mcd at a drive current of 70mA.
Viewing angle appears to be ~100°.
This is a wide-angle LED, and if I've told you once, I've told you a thousand times:
Wider viewing angles always, always, ALWAYS equal lower mcd values!!!!!!!!!
Spectrographic analysis of this LED.
USB2000 spectrometer graciously donated by P.L.
LEDs International, green LED, L15WAG55
Received 02-20-07, tested 02-22-07
This is a 5mm round LED in a water-clear epoxy case. It produces a fairly smooth circular beam with a brighter hotspot in the center.
Measures 5,710mcd at a drive current of 19.28mA.
Viewing angle appears to be 75-85°
This is a wide-angle LED, and if I've told you once, I've told you a hundred times:
Wider viewing angles always, always, ALWAYS equal lower mcd values!!!!!!!!!
Spectrographic analysis of this LED.
USB2000 spectrometer graciously donated by P.L.
LEDs International, green LED, L15NAG81
Received & tested 02-20-07
This is a 5mm round LED in a water-clear epoxy case. It produces a circular beam with a slight but very noticeable "hole" (dimmer spot) near the center.
Measures 15,900mcd at a drive current of 19.28mA.
Viewing angle appears to be 25-30°
Spectrographic analysis of this LED.
USB2000 spectrometer graciously donated by P.L.
5mm green LED, Nichia, part # NSPG510T
(Rec'd 07-31-06, tested 08-01-06)
This is a pure green LED, which emits at 525-535nm in the green region of the spectrum.
The LED has a dual-bond construction; and is Rank NF.
At a test current of 19.28mA, intensity (for two samples) was measured at:
4,910mcd and 5,140mcd.
Remember, wider viewing angles always, always, ALWAYS equal lower mcd values!
Vf was measured at 3.333 and 3.124 volts respectively.
I'm not equipped to measure beam angles at all. Looks like ~30° to me.
Spectrographic analysis of this green LED. Ocean Optics USB2000 Spectrometer on loan from TWO-CUBED.
5mm green LED, Manshun Int'l Ltd, part # YLPG5111A-NN
(Rec'd 03-22-06, tested 03-24-06)
This is a pure green LED, which emits at 525-535nm in the green region of the spectrum.
The LED has a dual-bond construction; it is apparently manufactured by Manshun Int'l Ltd. of Hong Kong.
At a test current of 19.28mA, intensity was measured at 8,890mcd.
Published intensity values range from 2,180mcd to 3,000mcd.
Vf was measured at 3.199 volts.
I'm not equipped to measure beam angles at all. It is published as 15°.
Spectrographic analysis of this green LED. Ocean Optics USB2000 Spectrometer on loan from TWO-CUBED.
Unknown brand 5mm Green LED
(Recieved on 12-04-04, tested 12-06-04)
This is one of two 5mm LEDs that a fan of the website sent. It is a GaN green LED in a standard round 5mm water-clear epoxy package.
This LED outputs a whitish, non-yellowish green color with a dominant wavelength (where you would point to on a color chart) of 521nm.
Photo of the LED's beam on the test target from ~12".
Measures 14,340mcd with a test current of 26mA.
5mm Water-Clear Green LED, www.etgtech.com, # ETG-5CE525-15
(Received ??-??-??, tested 07-07-04)
Like the blue ETG LED, I found these LEDs while looking for another product in response to an email I received.
This is a 5mm LED in a water-clear epoxy case, and uses what I believe is a Cree MegaBright die (light-emitting chip) to produce its light.
Dominant wavelength (where you would point to on a color chart) appears to be around 528nm, right about where it ought to be for this lamp.
Measures 8,400mcd with a test current of 26mA.
Viewing angle appears to be about 15 degrees.
UltraLEDs 5mm Green LED, (www.ultraleds.co.uk)
(Recieved on 03-04-04, tested 05-03-04)
This is a 5mm (T1 3/4) LED in a clear epoxy package that a fan of the website sent in early March 2004.
It produces a green beam with a dominant wavelength (where you would point to on a color chart) of approximately 528nm. My spectrometer is still broken, so I cannot confirm this with a measurement.
The beam has two distinct hotspots in it, with a sharp drop-off at its perimeter like the photograph below shows.
Measures 17,520mcd at a test current of 26mA.
The viewing angle appears to be around 15°. I don't have an instrument to measure this with though, so this is just a guess.
Nichia America, part # NSPG500S, 5mm round, 15°
(Received 11-03-03, tested 12-18-03)
In November 2003, I received an envelope from Nichia, and in it were several LEDs and a small flashlight. Here is one of those LEDs, the green NSPG500S, a 5mm LED in a standard, water-clear epoxy package.
When illuminated, the LED appears to emit a 525nm green light typical of other Nichia greens.
My spectrometer is broken, so I'll have to "eyeball" it...yup, it's green alright. :-) Looks to be close to 525nm, which is right where this LED ought to be.
Brightness for a standard ranking NSPG500S should be 11,600mcd at a drive current of 20mA.
According to the bag, this LED is a Rank 61T or 6IT part.
I don't know if that's a number "1" or a letter "I" on there.
Test current 25mA, Vf=3.68 volts
Used the LED Tester from Hosfelt Electronics.
Brightness is measured at 23,000mcd using a Meterman LM631 light meter.
ETG model ETG-5XB527-30 "Bright Green" 5mm round
This is ETG's latest offering in the green part of the spectrum. It is a bright lime green in color, noticeably less whitish than the typical Nichia green in the most commonly available rank. Dominant wavelength was eyeballed to be around 528-529nm; this was confirmed with a spectral analysis that was later taken.
Spectrum of this lamp.
Brightness was measured at 13,110mcd.
Basic chemistry is your typical InGaN on artificial sapphire. LED has a Vf of 3.4 to 3.6 volts, and should be fed 20mA. As is usual for this chemistry, you can boost that to 100mA by feeding it 10ms pulses with a 100ms rest between pulses (10% duty cycle).
Wilycon "Ultra Green" 5mm round
This is a 5mm round LED in a water-clear case. Brightness was measured at 2880mcd at 20mA, and the beam angle appears to be in the 20-25° range.
Dominant wavelength appears to be in the 526-529nm range.
Green: $290/Kpcs for 50000pcs order.
small qty: USD$0.75/pc Minimum USD$10 worth.
B.G. Micro, part # LED1050, $2.95 apiece
Several samples of this LED have recently shown up. A number of them came from one experimenter; another arrived some weeks later purchased by another.
All appear to be newer (November 1999) Nichia NSPG500BS green LEDs in clear, 5mm cases.
Samples #1 through #5 were all purchased at the same time, and arrived labelled as:
Sample #1, #2, and #3: Worst of a lot of 20
Sample #4 and #5: 2nd best and 3rd best out of 20.
Sample #6 was purchased some weeks later, and came in a green ESD bag labelled only as LED1050.
When hooked up, the first five samples appeared to operate much as labelled; the first three were rather dim; the last two were noticeably brighter.
However, sample #6 outshined them all by a clearly visible margin. It is probably comparable to the brightest LED in the original lot of 20 that were tested a couple of months
ago by Don Klipstein - this is the same lot of 20 that I received the three worst and the 2nd and 3rd best of.
The color of the LEDs vary from a slightly yellowish or lime shade of green to a more whitish, very slightly bluish green.
The brightest one - the single sample that came in a bag marked LED1050, outshined the brightest of Klipstein's samples by at least 15% and more probably around 20%.
An explanation of why this happens can be found on the blue LED page, in a test very similar to this one.
Contour beam image.
Spatial distribution curve.
LED and camera were 24" from screen for both of these images.
Created using the ProMetric System from Radiant Imaging.
This is a representative sample of a typical Nichia NSPG500BS, 15° viewing angle green LED.
Hosfelt Electronics part # 25-377 (Nichia NSPG500S, newer), $3.99
Before you hook this rather innocent looking LED up, you'd better go to the drugstore and buy some really dark sunglasses.
Packaged in a regular T1 3/4 clear case, this little powerhouse really impressed me even before I got it hooked up to a regular power source.
When connected to a meter and fed less than a milliamp, it was already too bright to look into comfortably. Forget about looking into this one at more normal currents of 20 to 30mA.
The literature says it's rated for 10,000mcd, but somehow I think it betters that mark by a little.
The color of this particular sample seems less whitish than is usual for this type of lamp. It also yellows less than others at reduced current. Although the yellow output does decrease, it doesn't seem to vanish entirely.
The sample maintains a fairly consistent color even at extremely high currents approaching 60mA - which was applied very briefly and well within the LED's duty cycle rating - but it does whiten noticeably anyway.
Spectrum of a typical Nichia NSPGxxxx LED.
Overall, I am highly impressed with this LED. However, the person who furnished this sample has one that's even more intense; possibly by a good 20% more.
If you need an LED that's blindingly bright, this is one model worth looking at.
It works extremely well even at low current. I wouldn't even try to stare into it when driven with much over 5mA or so, or you may need to buy one of those white and red canes!
This LED casts a medium-narrow 15-degree beam as shown on its test firing
More info on this sample will be posted as testing continues.
UPDATE 09-20-2000: Both this LED and the one directly below (also sold as Hosfelt 25-377) were rephotographed seconds apart under identical conditions.
In both cases, the camera's aperture was closed 1.5 stops to obtain these pictures.
Hosfelt Electronics part # 25-377 (Nichia NSPG520S, newer), $3.99
If you just read the above evaluation, you may be wondering, "why is there a second review of the exact same part?"
Good question. I might ask that myself, if I didn't actually see for myself something rather peculiar. The first Hosfelt 25-377 which was purchased last
spring showed a relatively narrow and inconsistent beam pattern. This Hosfelt 25-377 is a completely different animal - its beam is extremely wide; so wide it well overshot
the target it was photographed with!
This photograph shows the difference between this LED and the one directly above. The iris was closed 1.5 stops for both 25-377 pictures.
You will also see a "mottled" appearance in the photograph of this sample - this isn't an artifact from photography; the LED's beam really is mottled in an odd sort of way.
Here's what I suspect has happened:
Hosfelt Electronics, like many other hobbyist-accessible electronics parts suppliers, purchases surplus inventory from various parts manufacturers.
In this case, it was Nichia, and the purchase was their green T1 3/4 LED.
Last spring, they bought a bunch of Nichia NSPG500BS, and when those ran out,
their next purchase was Nichia NSPG520BS - the wide-angle version of this LED. Only Hosfelt didn't change the part number to reflect the different LEDs they got
the second time around. So who knows what kind of LED you might get when this latest batch runs out. It could be more wide-angle greens, or it could be another batch of narrow-beam ones.
My advice?
If beam angle is critical to your application but you're still on a budget, buy just one or whatever the minimum order is and see if they're alright. If they are, then go ahead and buy
all you need. If they aren't ok, then check places like All-Electronics or B.G. Micro and see if they have what you need.
(For the record, B.G. Micro sells the narrower beam NSPG500, and All-Electronics sells either the wide beam NSPG520 or a wide beam Toyoda Gosei model with roughly the same specs.
Care and Feeding: Green LEDs using gallium nitride technology should be fed 3.6 to 4.0 volts DC at 20 milliamps. You can take them to 30mA but only if
you can be sure you can deal with (get rid of) any extra heat the LED produces as a result. Clusters of them in a tightly enclosed, unventilated area will not appreciate being fed more than
their 20mA nominal rating.
All-Electronics part # LED-57 (Nichia NSPG520AS, older), $3.75 apiece / 10 for $30.00
This is a very bright "emerald green" LED, manufactured by Nichia. Like the green All-Electronics model, this appears to be
their NSPG520AS (revision A, with stopper) from 1-2 years ago; today's model is at least twice as powerful.
This lamp has a shade of green that hasn't been available until the last couple of years. It's a brilliant, slightly whitish green that doesn't have a yellowish appearance at all unless the LED
is operated at currents very far below its 20mA to 30mA rating. Then it turns yellowish, becoming almost a pure "lime green".
Spectrally, these LEDs have the widest spectrum of any of the nitride types available; with output from red to mid-blue, but
really spiking high in the mid-green (naturally). When run at lower currents though, virtually all output in the blue region vanishes,
and the green spike or hump shifts a little towards the red end of the spectrum; to give it that kind of lime green color.
When operated at or above maximum ratings, the blue output increases dramatically, giving the LED a whiter appearance than
normal. This particular LED has a 45 degree beam, 1200mcd brightness and 2mW actual output power.
Newer Nichia LEDs with the same part number should easily double these figures.
Close-up of a Nichia green LED, showing the unique internal structure.
Three Nicha LEDs in their police photograph lineup. :)
Can you pick out the NSPE590S?
Nichia model NSPGF50S, newer model, $8 apiece
An LED that comes with a warning?
If you like your LEDs bright enough to actually damage your eyes and make your prosthetic appliance dealer a few thousand extra bucks, this LED is for you.
Packaged with this LED is its specifications sheet, with the following:
"The LED light output is strong enough to injure human eyes. Precautions
must be taken to prevent looking directly at the LED with the unaided eyes for more than a few seconds."
With some of Nichia's models (especially older models) this might not entirely be true. WIth this brilliant green model, I'd heed this advice, and heed it well.
Failing that, be prepared to send your eye doctor and his family on a European vacation this summer.
Packaged in a small, flat, rectangular case, this LED is truely bright. It produces a brilliant dot of whitish-green light with a very wide
110 by 80 degree beam. Throw one of these in a keychain flashlight and you'll never miss that keyhole again. They have a fairly wide spectrum
as nitride-based LEDs are concerned, with emission from 650nm (mid-red) to 450nm (mid-blue); but showing a strong peak in the 525 to 530nm green area.
This is the type of LED that is likely to end up in the newest generation of handheld display devices such as cellular telephones, tiny computers like Palm Pilots,
and other similar devices. More sophicticated products though might end up using the white LED in this line (or using embedded SMD chip-type white LEDs), so as to permit the use of full-color LCD screens.
This model is also plenty bright enough to find its way into large, full color video screens like those used as advertising or in baseball parks.
Looking to add front marker lights on your bicycle like some police are using now? Impress your friends and BE SEEN, use three or four of these babies behind
a clear or green-tinted reflector lens. Green bicycle lights do exist, but they aren't very popular because until now, green LEDs just haven't been bright enough.
Once these LEDs become widely available, that ought to change.
UPDATE 01-19: I replaced the weak orange rectangular LED in a Star Trek "phaser" keychain light with one of these - it's about fifty times brighter, and turns the
otherwise worthless pocket-sized gizmo into a really useful pocket flashlight. It should light an entire room well enough to see by at night, and it will certainly light keyholes or the insides of purses & handbags nicely in any conditions.
It might even be brighter had I bothered to change the resistor - but it's fine the way it is.
This beam pattern is the same for all Nichia "F" series flat LEDs.
Toyoda Gosei, part # E1L51-3G, approx. $2
This is a fairly unique LED, in that it has a noticeably whiter color than most other gallium nitride green models.
It isn't quite as bright, but with a very narrow beam of 6 to 8 degrees, it can be seen a very long distance away.
Lower current testing showed it turns yellowish like the All-Electronics green, but not quite as much.
The case style is T1 3/4 but it's somewhat elongated with a more conical appearance to it than most T1 3/4 LEDs.
This is because the end of the LED acts like a lens to focus the beam, so you will find that all very narrow beam LEDs
have this characteristic.