need help with true purple LEDs

[the13bats]

I need some info on true purple LED's

I was over at bike week Daytona and noticed more than not bikes had the LED light strips, I want some for several projects but I must have purple,

These bike LEDS in most cases were used to give glow to the engine and wheels,
Most used Red, Blue, Orange, White, and rather bright and crisp but my post is about Purple which I only saw on a couple bikes.

I popped on Ebay and see that "kits" made for cycles and cars are a bit pricey but for a fraction of that price of a kit a person who likes to do it themselves can buy a 500cm roll of LED strip. this is good as I have lots of places to use the strips that I can custom cut to size.

I researched and learned not all strip is the same, 5050 vs 3528 and then LED count per foot or roll.

Many times auctions while it "looks" purple call the color pink/purple or Fuchsia/purple I saw bikes at bike week with what I call pink/fushsia and that is NOT what I want I want "Purple"

I also see some purple has UV tagged into the name but I have a handful of UV purple LEDS they are far paler in color than what I call purple and not bright as far as lighting up anything.

So I think this will be easy I will include a html color code chart to show you guys what I call purple, not so easy, different monitors will show it different.
but here is a try,
What I want is the color they call "pansy" some of the ebay purple led strip look like this color and it's the purple color I saw and liked on bikes in person,

http://samcowholesalesales.com/images/color_chart.gif

My UV purple leds seem to be more like the color they call lilac too pale and not enough light given off.
And the pink I saw I didn't want at all this place calls it magenta.

So here goes my questions how do I know if I will order and get "purple"?
Do I avoid the ones with UV in the title?
Do I only look for the 5050 or will the 3528 work?

I realize for a person to help they will have had to have seen in person all three LED shades I'm talking about,

If you want to take a look on ebay I was searching under "purple led strip" I of course want 600 count....

Many thanks!
Cheers,
Bats.

Image tags removed see Rule #3 Do not Hot Link images. Please host on an image site, Imageshack or similar and repost – Thanks Norm

 

[RoGuE_StreaK]

Don't know if such a purple exists as a dedicated LED, but something that may work is to get RGB LEDs (Red-Green-Blue, three LEDs in one package) and custom tweak the amount of blend of each (probably just Red and Blue) to see if you can get the colour you want. Can be done in an analytical semi-precise manner using the likes of an Arduino, or a suck-n-see manner using some variable resistors.

 

[RoGuE_StreaK]

PS. You'd probably have better luck if you check out a visible spectrum wavelength chart, so then you could say "I want 405nm", or "I want 420nm", etc. Better for specifying an exact colour.

 

[inetdog]

Be careful that you know what you are asking for. The color beyond blue on the way to ultraviolet is called violet.
The color that our eyes perceive as "purple" is a mixture of red and blue or violet without the spectral colors in between.
You may find that all you need to do to get the violet LEDs you do not like to give you the purple you want is to mix in some deep red.

 

[the13bats]

I do not need to mix colors it is available off the shelf, like I said I have seen it, I even one it, I have the color on my trike and in my computer....I just want to buy the right roll of strip, hoping someone who bought some would see this thread,

Here is a chart you suggested to help a little,

If the glow is 405-420 then I do believe that would work, while it looks a bit blue to me I believe the glow would be more purple....so anyone bought a roll of this?

 

[the13bats]

Hey Norm I did it again, not on purpose, I cant find how to delete an image....
Here is the address to the image,
http://ledmuseum.candlepower.us/34/x5tuv7.gif

 

[evilc66]

You don't want violet LEDs, or UV (or any LED with a specified wavelength). Neither are bright enough to get the effect you want.

What you want is a blue LED with a red phosphor, which is what will commonly be called purple, pink, or magenta. These will be a lot brighter, but you are at the mercy of the supplier as to the amount of red phosphor being applied, and as a result, the specific tint of the color. A 5050 RGB LED strip might get you what you need, as you can just manipulate the red and blue to get the tint you want. The dies on the LED are close enough together that you will never see the color separation, and will give you similar end results to the red phosphor coated blue LED.

 

[the13bats]

You don't want violet LEDs, or UV (or any LED with a specified wavelength). Neither are bright enough to get the effect you want.

What you want is a blue LED with a red phosphor, which is what will commonly be called purple, pink, or magenta. These will be a lot brighter, but you are at the mercy of the supplier as to the amount of red phosphor being applied, and as a result, the specific tint of the color. A 5050 RGB LED strip might get you what you need, as you can just manipulate the red and blue to get the tint you want. The dies on the LED are close enough together that you will never see the color separation, and will give you similar end results to the red phosphor coated blue LED.

Coolness....someone savvy to what I am talking about,
You are on it, like I said the "UV" loose LEDS I have are an odd light lavender color and do not put out much light,
and you explaining the "purple" color is really a blue LED with red phosphor makes perfect sense as different manufactures are going to use more or less red and that will give us more or less of that pink color I do not want.

This icon is very close to the color I desire but it might show different on yor computer... but it's super close to the "Purple" LED pod I have in my computer tower and on our trike,

The reason I am would rather have a fixed color strip than the RGB is I will be cutting it into several pieces to place where I desire and would have to contend with linking the pieces of strip so they all would connect to each other and the RGB controller,

I have to get going but at least I have another piece of the puzzle of purple LEDs many thanks!

 

[evilc66]

If you work with 5050 based RGB LED strips, each section of 3 LEDs is run in parallel with each other. You can cut up the strips as much as you like, but as long as the wiring between the sections is the same as it would be if it were still one long strip, then you can adjust the supply voltage to each color once, and then forget about it. Depending on how many strips you end up using, you could probably make a pair of LM350 based voltage regulators to set the output of the red and blue channels. After you get the color you want, just epoxy/hot glue over the potentiometer to keep the settings.

 

[FRITZHID]

With the plcc6 (5050) LEDs, your best option for a true purple with brightness IS using RGB And a proper controller....
You only need connect the r & b leads and the controller will allow you to find tune your desired color/tint and brightness. IF you are dead set against using them, your choices are going to be far more limited and you will need to do allot of searching. They're not many manufacturers of pure color LEDs like you're looking for because of the rgb option. It's more versatile than single color, cheaper to manufacture (no phosphor).
That being said, you could experiment with red/blue LEDs and tinted coverings but anytime you filter light, it's brightness is reduced, hence why most people use rgb LEDs and a pwm controller. They aren't expensive, run on a wide variety of voltages, user friendly, programmable, most use a thin cellphone sized remote, ect.
If you have any questions on these options, please feel free to contact me personally and I'll help any way I can. (I just happen to do these exact custom mods on cars, bikes, boats and buildings)

 

[inetdog]

I do not think I have seen a conclusive answer from the OP whether what they really want is violet (single narrow wavelength range) or purple (mix of two widely separated wavelengths). They are distinctly different in subjective effect.

 

[Sunbrilo]

This is a long-wave UV LED, a wavelength of 395nm violet blue chip + phosphor composition.
Jason

 

[JoakimFlorence]

If asked, the vast majority of people in the world would be unable to explicate the proper distinction between "purple" and "violet". Purple is a mix of blue and red. Violet is a particular territory of wavelengths in the visible spectrum, a very far blue hue.

The reason why even true violet appears a little bit purple in color (and why there is so much confusion) is because the red receptors in the eye have a small amount of overlap sensitivity towards violet wavelengths, not just the longer red wavelengths of light. So the light given off by violet wavelength LED emitters superficially appears very similar to purple LED lights. In fact it's almost impossible for me to tell the difference.