Question 1

Is the uv/purple option actually uv (usually 395 nm)? will it cause fluorescent objects to glow? i need to use it for that purpose

Accepted Answer

"UV/Purple" is a wavelength of about 395-400nm. This wavelength will cause a faint somewhat dim "glow" in florescent objects, BUT it will have a visible purple light emitting from the diode. This is because at 395nm more of the light emitted is VERY near the wavelength of regular purple light so you will get both lights (weak UV & regular purple) emitting from the LED. This LED emits more purple light than the useful UV you've after. It will work, but you will need quite a few focused at a single point to be of any real use for you. Also UV at the wavelength in my opinion is somewhat useless unless there are 20+ of them and you dont mind purple light flooding the area) . This type of UV is referred to as "Blacklight-Blue" because this UV source is a mix of invisible (black light)  but near the  blue light spectrum causing the purple.

Then there is "Blacklight-Black" Yep, this is like florescent Halloween lights that don't appear to be bright at all but things REALLY GLOW.

What you need is an LED with a wavelength of about 350-365nm. These do not emit much visible purple light but emit the INVISIBLE UV light that causes the glow you want, in fact at this shorter wavelength the UV light really causes a MUCH brighter and intense fluorescent glow, and without all the purple light flooding it. Most people tend to think they are junk and/or not working (due to the short wavelength UV light being invisible and not knowing that). They are more expensive but you get what you pay for. That's why some UV flashlights are very inexpensive (under $5) and others are pricey ( $50+) being of equivalent size but not even comparable in performance. Forensic UV light are this type (with few exceptions)

Question 2

So i ordered 2 bags of 100 white LEDs, why did 1 bag have 70 and the other had 69?

Accepted Answer

People can,t count.I had a order that was suppose to be 100pcs and only received about 40. Email the vendor.I emiled and received a full order

Question 3

what do i need to use to power these led diodes?

Accepted Answer

LEDs have a forward voltage drop for the color your using. I think white is around 2.5+ volts or so. If you plug one into a 12 volt supply by itself it will burn up. You can Google led resistor and use the calculator to find the resistor based on input voltage. Most LEDs can't take more than 20 milliamps.

Question 4

how many lumins does each LED give off for each of the 5 colors? (estimate?)

Accepted Answer

I make Christmas tree ornaments with them. 5 lamp topper star will light up a 14x18 room pretty well. About like a 40 watt reading lamp.

Product Dimensions	1.27 x 1.27 x 12.7 cm; 2.83 g
Item Weight	0.1 Ounces
Specific uses	Appliance
Finish types	Clear
Specification met	Energy Star
Batteries required	No
Included components	100 Pcs 5mm Clear Round Head White LED Emitting Diode

5mm White LED Diode Lights, Pack of 100 Clear Transparent DC 3V 20mA 5mm Emitting Diodes LEDs Bulb for Home DIY Science Project Electronics Components Light

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